Merge commit '0072d11f' into tmp-learn

81 files changed, 3423 insertions, 1194 deletions

diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 7809fecd..0a758cff 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -134,21 +134,11 @@ docker_fedora-34-amd64:
     IMG_NAME: "fedora-34-amd64"
   <<: *docker_build
 
-docker_centos-7-amd64:
-  variables:
-    IMG_NAME: "centos-7-amd64"
-  <<: *docker_build
-
 docker_centos-8-amd64:
   variables:
     IMG_NAME: "centos-8-amd64"
   <<: *docker_build
 
-docker_ubuntu-14_04-amd64:
-  variables:
-    IMG_NAME: "ubuntu-14.04-amd64"
-  <<: *docker_build
-
 docker_ubuntu-16_04-amd64:
   variables:
     IMG_NAME: "ubuntu-16.04-amd64"
@@ -312,18 +302,10 @@ build-fedora-34-amd64:
   <<: *build-linux
   image: registry.nic.cz/labs/bird:fedora-33-amd64
 
-build-centos-7-amd64:
-  <<: *build-linux
-  image: registry.nic.cz/labs/bird:centos-7-amd64
-
 build-centos-8-amd64:
   <<: *build-linux
   image: registry.nic.cz/labs/bird:centos-8-amd64
 
-build-ubuntu-14_04-amd64:
-  <<: *build-linux
-  image: registry.nic.cz/labs/bird:ubuntu-14.04-amd64
-
 build-ubuntu-16_04-amd64:
   <<: *build-linux
   image: registry.nic.cz/labs/bird:ubuntu-16.04-amd64
@@ -466,14 +448,7 @@ pkg-fedora-33-amd64:
 pkg-fedora-34-amd64:
   <<: *pkg-rpm
   needs: [build-fedora-34-amd64]
-  image: registry.nic.cz/labs/bird:fedora-34-amd64
-
-pkg-centos-7-amd64:
-  <<: *pkg-rpm-wa
-  variables:
-    LC_ALL: en_US.UTF-8
-  needs: [build-centos-7-amd64]
-  image: registry.nic.cz/labs/bird:centos-7-amd64
+  image: registry.labs.nic.cz/labs/bird:fedora-34-amd64
 
 pkg-centos-8-amd64:
   <<: *pkg-rpm-wa
diff --git a/INSTALL b/INSTALL
index 7a179284..c1094ee5 100644
--- a/INSTALL
+++ b/INSTALL
@@ -27,9 +27,9 @@ Requirements
 
 For compiling BIRD you need these programs and libraries:
 
- - GNU C Compiler (or LLVM Clang)
+ - GNU C Compiler (or LLVM Clang) capable of compiling C11 code
  - GNU Make
- - GNU Bison
+ - GNU Bison (at least 3.0)
  - GNU M4
  - Flex
 
diff --git a/NEWS b/NEWS
index c1e51af2..e61a0b74 100644
--- a/NEWS
+++ b/NEWS
@@ -1,3 +1,11 @@
+Version 2.0.10 (2022-06-16)
+  o BGP performance improvements
+  o BFD: New 'strict bind' option
+  o RPKI: VRF support
+  o Allow use of 240.0.0.0/4 as a private range
+  o BIRD client uses exit status to report errors
+  o Important bugfixes
+
 Version 2.0.9 (2022-02-09)
   o BGP: Flowspec validation procedure
   o Babel: MAC authentication support
diff --git a/aclocal.m4 b/aclocal.m4
index 58c48791..cc45b54a 100644
--- a/aclocal.m4
+++ b/aclocal.m4
@@ -1,5 +1,6 @@
 dnl ** Additional Autoconf tests for BIRD configure script
 dnl ** (c) 1999 Martin Mares <mj@ucw.cz>
+dnl ** (c) 2021 Maria Matejka <mq@jmq.cz>
 
 AC_DEFUN([BIRD_CHECK_POINTER_ALIGNMENT],
 [
@@ -35,14 +36,23 @@ AC_DEFUN([BIRD_CHECK_THREAD_LOCAL],
     AC_COMPILE_IFELSE([
       AC_LANG_PROGRAM(
         [
-	  _Thread_local static int x = 42;
+	  static _Thread_local int x = 42;
 	],
 	[]
       )
     ],
     [bird_cv_thread_local=yes],
+    [AC_COMPILE_IFELSE([
+      AC_LANG_PROGRAM(
+       [
+         static __thread int x = 42;
+       ],
+       []
+      )
+    ],
+    [bird_cv_thread_local=__thread],
     [bird_cv_thread_local=no]
-    )
+    )])
   )
 ])
 
diff --git a/bird-gdb.py b/bird-gdb.py
index 62c0ec87..077703f9 100644
--- a/bird-gdb.py
+++ b/bird-gdb.py
@@ -122,7 +122,7 @@ class BIRDFLinePrinter(BIRDPrinter):
                         "n": n,
                         "code": str(self.val['items'][n]['fi_code']),
                     } if n % 8 == 0 else str(self.val['items'][n]['fi_code']) for n in range(cnt)]))
-        
+
 
 class BIRDFExecStackPrinter(BIRDPrinter):
     "Print BIRD's struct f_exec_stack"
@@ -140,6 +140,118 @@ class BIRDFExecStackPrinter(BIRDPrinter):
                     "n": n
                         } for n in range(cnt-1, -1, -1) ])
 
+
+class BIRD:
+    def skip_back(t, i, v):
+        if isinstance(t, str):
+            t = gdb.lookup_type(t)
+        elif isinstance(t, gdb.Value):
+            t = gdb.lookup_type(t.string())
+        elif not isinstance(t, gdb.Type):
+            raise Exception(f"First argument of skip_back(t, i, v) must be a type, got {type(t)}")
+
+        t = t.strip_typedefs()
+        nullptr = gdb.Value(0).cast(t.pointer())
+
+        if isinstance(i, gdb.Value):
+            i = i.string()
+        elif not isinstance(i, str):
+            raise Exception(f"Second argument of skip_back(t, i, v) must be a item name, got {type(i)}")
+
+        if not isinstance(v, gdb.Value):
+            raise Exception(f"Third argument of skip_back(t, i, v) must be a value, got {type(v)}")
+        if v.type.code != gdb.TYPE_CODE_PTR and v.type.code != gdb.TYPE_CODE_REF:
+            raise Exception(f"Third argument of skip_back(t, i, v) must be a pointer, is {v.type} ({v.type.code})")
+        if v.type.target().strip_typedefs() != nullptr[i].type:
+            raise Exception(f"Third argument of skip_back(t, i, v) points to type {v.type.target().strip_typedefs()}, should be {nullptr[i].type}")
+
+        uintptr_t = gdb.lookup_type("uintptr_t")
+        taddr = v.dereference().address.cast(uintptr_t) - nullptr[i].address.cast(uintptr_t)
+        return gdb.Value(taddr).cast(t.pointer())
+
+    class skip_back_gdb(gdb.Function):
+        "Given address of a structure item, returns address of the structure, as the SKIP_BACK macro does"
+        def __init__(self):
+            gdb.Function.__init__(self, "SKIP_BACK")
+
+        def invoke(self, t, i, v):
+            return BIRD.skip_back(t, i, v)
+
+
+BIRD.skip_back_gdb()
+
+
+class BIRDList:
+    def __init__(self, val):
+        ltype = val.type.strip_typedefs()
+        if ltype.code != gdb.TYPE_CODE_UNION or ltype.tag != "list":
+            raise Exception(f"Not a list, is type {ltype}")
+
+        self.head = val["head"]
+        self.tail_node = val["tail_node"]
+
+        if str(self.head.address) == '0x0':
+            raise Exception("List head is NULL")
+
+        if str(self.tail_node["prev"].address) == '0x0':
+            raise Exception("List tail is NULL")
+
+    def walk(self, do):
+        cur = self.head
+        while cur.dereference() != self.tail_node:
+            do(cur)
+            cur = cur.dereference()["next"]
+
+
+class BIRDListLength(gdb.Function):
+    """Returns length of the list, as in
+    print $list_length(routing_tables)"""
+    def __init__(self):
+        super(BIRDListLength, self).__init__("list_length")
+
+    def count(self, _):
+        self.cnt += 1
+
+    def invoke(self, l):
+        self.cnt = 0
+        BIRDList(l).walk(self.count)
+        return self.cnt
+
+BIRDListLength()
+
+class BIRDListItem(gdb.Function):
+    """Returns n-th item of the list."""
+    def __init__(self):
+        super(BIRDListItem, self).__init__("list_item")
+
+    class BLException(Exception):
+        def __init__(self, node, msg):
+            Exception.__init__(self, msg)
+            self.node = node
+
+    def count(self, node):
+        if self.cnt == self.pos:
+            raise self.BLException(node, "Node found")
+
+        self.cnt += 1
+
+    def invoke(self, l, n, t=None, item="n"):
+        self.cnt = 0
+        self.pos = n
+        bl = BIRDList(l)
+        try:
+            bl.walk(self.count)
+        except self.BLException as e:
+            if t is None:
+                return e.node
+            else:
+                return BIRD.skip_back(t, item, e.node)
+
+        raise Exception("List too short")
+
+BIRDListItem()
+
+
 def register_printers(objfile):
     objfile.pretty_printers.append(BIRDFInstPrinter.lookup)
     objfile.pretty_printers.append(BIRDFValPrinter.lookup)
diff --git a/conf/cf-lex.l b/conf/cf-lex.l
index 11bcdb18..04e0b3a5 100644
--- a/conf/cf-lex.l
+++ b/conf/cf-lex.l
@@ -577,6 +577,8 @@ check_eof(void)
   return 0;
 }
 
+static inline void cf_swap_soft_scope(void);
+
 static struct symbol *
 cf_new_symbol(const byte *c)
 {
@@ -586,6 +588,8 @@ cf_new_symbol(const byte *c)
   if (l > SYM_MAX_LEN)
     cf_error("Symbol too long");
 
+  cf_swap_soft_scope();
+
   s = cfg_allocz(sizeof(struct symbol) + l + 1);
   *s = (struct symbol) { .scope = conf_this_scope, .class = SYM_VOID, };
   strcpy(s->name, c);
@@ -676,8 +680,8 @@ cf_localize_symbol(struct symbol *sym)
     return sym;
 
   /* If the scope is the current, it is already defined in this scope. */
-  if (sym->scope == conf_this_scope)
-    cf_error("Symbol already defined");
+  if (cf_symbol_is_local(sym))
+    cf_error("Symbol '%s' already defined", sym->name);
 
   /* Not allocated here yet, doing it now. */
   return cf_new_symbol(sym->name);
@@ -839,6 +843,8 @@ cf_push_scope(struct symbol *sym)
 void
 cf_pop_scope(void)
 {
+  ASSERT(!conf_this_scope->soft_scopes);
+
   conf_this_scope->active = 0;
   conf_this_scope = conf_this_scope->next;
 
@@ -846,6 +852,52 @@ cf_pop_scope(void)
 }
 
 /**
+ * cf_push_soft_scope - enter new soft scope
+ *
+ * If we want to enter a new anonymous scope that most likely will not contain
+ * any symbols, we can use cf_push_soft_scope() insteas of cf_push_scope().
+ * Such scope will be converted to a regular scope on first use.
+ */
+void
+cf_push_soft_scope(void)
+{
+  if (conf_this_scope->soft_scopes < 0xfe)
+    conf_this_scope->soft_scopes++;
+  else
+    cf_push_scope(NULL);
+}
+
+/**
+ * cf_pop_soft_scope - leave a soft scope
+ *
+ * Leave a soft scope entered by cf_push_soft_scope().
+ */
+void
+cf_pop_soft_scope(void)
+{
+  if (conf_this_scope->soft_scopes)
+    conf_this_scope->soft_scopes--;
+  else
+    cf_pop_scope();
+}
+
+/**
+ * cf_swap_soft_scope - convert soft scope to regular scope
+ *
+ * Soft scopes cannot hold symbols, so they must be converted to regular scopes
+ * on first use. It is done automatically by cf_new_symbol().
+ */
+static inline void
+cf_swap_soft_scope(void)
+{
+  if (conf_this_scope->soft_scopes)
+  {
+    conf_this_scope->soft_scopes--;
+    cf_push_scope(NULL);
+  }
+}
+
+/**
  * cf_symbol_class_name - get name of a symbol class
  * @sym: symbol
  *
diff --git a/conf/conf.c b/conf/conf.c
index 580a6472..17424402 100644
--- a/conf/conf.c
+++ b/conf/conf.c
@@ -140,6 +140,7 @@ config_parse(struct config *c)
   protos_preconfig(c);
   rt_preconfig(c);
   cf_parse();
+  rt_postconfig(c);
 
   if (EMPTY_LIST(c->protos))
     cf_error("No protocol is specified in the config file");
diff --git a/conf/conf.h b/conf/conf.h
index 4ccaa54e..50e01bf5 100644
--- a/conf/conf.h
+++ b/conf/conf.h
@@ -44,7 +44,7 @@ struct config {
 
   int cli_debug;			/* Tracing of CLI connections and commands */
   int latency_debug;			/* I/O loop tracks duration of each event */
-  int pipe_debug;			/* Track route propagation through pipes */
+  int table_debug;			/* Track route propagation through tables */
   u32 latency_limit;			/* Events with longer duration are logged (us) */
   u32 watchdog_warning;			/* I/O loop watchdog limit for warning (us) */
   u32 watchdog_timeout;			/* Watchdog timeout (in seconds, 0 = disabled) */
@@ -136,7 +136,8 @@ struct sym_scope {
   HASH(struct symbol) hash;		/* Local symbol hash */
 
   uint slots;				/* Variable slots */
-  int active;				/* Currently entered */
+  byte active;				/* Currently entered */
+  byte soft_scopes;			/* Number of soft scopes above */
 };
 
 extern struct sym_scope *global_root_scope;
@@ -202,6 +203,9 @@ struct symbol *cf_get_symbol(const byte *c);
 struct symbol *cf_default_name(char *template, int *counter);
 struct symbol *cf_localize_symbol(struct symbol *sym);
 
+static inline int cf_symbol_is_local(struct symbol *sym)
+{ return (sym->scope == conf_this_scope) && !conf_this_scope->soft_scopes; }
+
 /**
  * cf_define_symbol - define meaning of a symbol
  * @sym: symbol to be defined
@@ -225,6 +229,9 @@ struct symbol *cf_localize_symbol(struct symbol *sym);
 
 void cf_push_scope(struct symbol *);
 void cf_pop_scope(void);
+void cf_push_soft_scope(void);
+void cf_pop_soft_scope(void);
+
 char *cf_symbol_class_name(struct symbol *sym);
 
 /* Parser */
diff --git a/conf/confbase.Y b/conf/confbase.Y
index 58890cd6..241c332d 100644
--- a/conf/confbase.Y
+++ b/conf/confbase.Y
@@ -76,6 +76,7 @@ CF_DECLS
   struct f_attr_bit fab;
   struct f_lval flv;
   struct f_line *fl;
+  struct f_arg *fa;
   const struct filter *f;
   struct f_tree *e;
   struct f_trie *trie;
@@ -111,7 +112,7 @@ CF_DECLS
 %type <i> expr bool pxlen4
 %type <time> expr_us time
 %type <a> ipa
-%type <net> net_ip4_ net_ip6_ net_ip6 net_ip_ net_ip net_or_ipa
+%type <net> net_ip4_ net_ip4 net_ip6_ net_ip6 net_ip_ net_ip net_or_ipa
 %type <net_ptr> net_ net_any net_vpn4_ net_vpn6_ net_vpn_ net_roa4_ net_roa6_ net_roa_ net_ip6_sadr_ net_mpls_
 %type <ad> label_stack_start label_stack
 
@@ -154,14 +155,14 @@ conf: definition ;
 definition:
    DEFINE symbol '=' term ';' {
      struct f_val val;
-     if (f_eval(f_linearize($4), &val) > F_RETURN) cf_error("Runtime error");
+     if (f_eval(f_linearize($4, 1), &val) > F_RETURN) cf_error("Runtime error");
      cf_define_symbol($2, SYM_CONSTANT | val.type, val, lp_val_copy(cfg_mem, &val));
    }
  ;
 
 expr:
    NUM
- | '(' term ')' { $$ = f_eval_int(f_linearize($2)); }
+ | '(' term ')' { $$ = f_eval_int(f_linearize($2, 1)); }
  | symbol_known {
      if ($1->class != (SYM_CONSTANT | T_INT)) cf_error("Number constant expected");
      $$ = SYM_VAL($1).i; }
@@ -307,6 +308,15 @@ net_:
 
 /* Networks - regular */
 
+net_ip4:
+   net_ip4_
+ | CF_SYM_KNOWN {
+     if (($1->class != (SYM_CONSTANT | T_NET)) || (SYM_VAL($1).net->type != NET_IP4))
+       cf_error("IPv4 network constant expected");
+     $$ = * SYM_VAL($1).net;
+   }
+ ;
+
 net_ip6:
    net_ip6_
  | CF_SYM_KNOWN {
diff --git a/conf/flowspec.Y b/conf/flowspec.Y
index 56a7c5dc..dbdbdda5 100644
--- a/conf/flowspec.Y
+++ b/conf/flowspec.Y
@@ -142,7 +142,7 @@ flow_frag_opts:
  ;
 
 flow4_item:
-   flow_srcdst net_ip {
+   flow_srcdst net_ip4 {
      flow_builder_set_type(this_flow, $1);
      flow_builder4_add_pfx(this_flow, (net_addr_ip4 *) &($2));
    }
diff --git a/configure.ac b/configure.ac
index 321bed95..330add87 100644
--- a/configure.ac
+++ b/configure.ac
@@ -36,12 +36,6 @@ AC_ARG_ENABLE([memcheck],
   [enable_memcheck=yes]
 )
 
-AC_ARG_ENABLE([pthreads],
-  [AS_HELP_STRING([--enable-pthreads], [enable POSIX threads support @<:@try@:>@])],
-  [],
-  [enable_pthreads=try]
-)
-
 AC_ARG_ENABLE([libssh],
   [AS_HELP_STRING([--enable-libssh], [enable LibSSH support in RPKI @<:@try@:>@])],
   [],
@@ -125,25 +119,19 @@ if test -z "$GCC" ; then
 fi
 
 BIRD_CHECK_THREAD_LOCAL
-if test "$bird_cv_thread_local" = yes ; then
-  AC_DEFINE([HAVE_THREAD_LOCAL], [1], [Define to 1 if _Thread_local is available])
+if test "$bird_cv_thread_local" = no ; then
+  AC_MSG_ERROR([This program requires thread local storage.])
+elif test "$bird_cv_thread_local" != yes ; then
+  AC_DEFINE_UNQUOTED([_Thread_local], [$bird_cv_thread_local], [Legacy _Thread_local])
 fi
 
-if test "$enable_pthreads" != no ; then
-  BIRD_CHECK_PTHREADS
+BIRD_CHECK_PTHREADS
 
-  if test "$bird_cv_lib_pthreads" = yes ; then
-    AC_DEFINE([USE_PTHREADS], [1], [Define to 1 if pthreads are enabled])
-    CFLAGS="$CFLAGS -pthread"
-    LDFLAGS="$LDFLAGS -pthread"
-    proto_bfd=bfd
-  elif test "$enable_pthreads" = yes ; then
-    AC_MSG_ERROR([POSIX threads not available.])
-  fi
-
-  if test "$enable_pthreads" = try ; then
-    enable_pthreads="$bird_cv_lib_pthreads"
-  fi
+if test "$bird_cv_lib_pthreads" = yes ; then
+  CFLAGS="$CFLAGS -pthread"
+  LDFLAGS="$LDFLAGS -pthread"
+else
+  AC_MSG_ERROR([POSIX threads not available.])
 fi
 
 # This is assumed to be necessary for proper BIRD build
@@ -304,8 +292,7 @@ if test "$enable_mpls_kernel" != no ; then
   fi
 fi
 
-all_protocols="$proto_bfd babel bgp mrt ospf perf pipe radv rip rpki static"
-
+all_protocols="bfd babel bgp mrt ospf perf pipe radv rip rpki static"
 all_protocols=`echo $all_protocols | sed 's/ /,/g'`
 
 if test "$with_protocols" = all ; then
@@ -350,10 +337,16 @@ case $sysdesc in
     ;;
 esac
 
-AC_CHECK_HEADERS_ONCE([alloca.h syslog.h])
-AC_CHECK_HEADER([sys/mman.h], [AC_DEFINE([HAVE_MMAP], [1], [Define to 1 if mmap() is available.])])
+AC_CHECK_HEADERS_ONCE([alloca.h syslog.h stdatomic.h])
+AC_CHECK_HEADER([sys/mman.h], [AC_DEFINE([HAVE_MMAP], [1], [Define to 1 if mmap() is available.])], have_mman=no)
+AC_CHECK_FUNC([aligned_alloc], [AC_DEFINE([HAVE_ALIGNED_ALLOC], [1], [Define to 1 if aligned_alloc() is available.])], have_aligned_alloc=no)
 AC_CHECK_MEMBERS([struct sockaddr.sa_len], [], [], [#include <sys/socket.h>])
 
+if test "$have_aligned_alloc" = "no" && test "$have_mman" = "no" ; then
+  AC_MSG_ERROR([No means of aligned alloc found. Need mmap() or aligned_alloc().])
+fi
+
+
 AC_C_BIGENDIAN(
   [AC_DEFINE([CPU_BIG_ENDIAN], [1], [Define to 1 if cpu is big endian])],
   [AC_DEFINE([CPU_LITTLE_ENDIAN], [1], [Define to 1 if cpu is little endian])],
@@ -409,7 +402,7 @@ if test "$enable_debug" = yes ; then
     fi
   fi
 
-  if test "enable_debug_expensive" = yes ; then
+  if test "$enable_debug_expensive" = yes ; then
     AC_DEFINE([ENABLE_EXPENSIVE_CHECKS], [1], [Define to 1 if you want to run expensive consistency checks.])
   fi
 fi
@@ -474,7 +467,6 @@ AC_MSG_RESULT([        Object directory:	$objdir])
 AC_MSG_RESULT([        Iproute2 directory:	$iproutedir])
 AC_MSG_RESULT([        System configuration:	$sysdesc])
 AC_MSG_RESULT([        Debugging:		$enable_debug])
-AC_MSG_RESULT([        POSIX threads:		$enable_pthreads])
 AC_MSG_RESULT([        Routing protocols:	$protocols])
 AC_MSG_RESULT([        LibSSH support in RPKI:	$enable_libssh])
 AC_MSG_RESULT([        Kernel MPLS support:	$enable_mpls_kernel])
diff --git a/doc/bird.sgml b/doc/bird.sgml
index c9ce670b..a4d7cb0c 100644
--- a/doc/bird.sgml
+++ b/doc/bird.sgml
@@ -684,6 +684,30 @@ to set options.
 	limit to the settle time from the initial ROA table change even if
 	there are consecutive updates gradually renewing the settle time.
 	Default: 20 s.
+
+	<tag><label id="rtable-gc-threshold">gc threshold <m/number/</tag>
+	Specify a minimum amount of removed networks that triggers a garbage
+	collection (GC) cycle. Default: 1000.
+
+	<tag><label id="rtable-gc-period">gc period <m/time/</tag>
+	Specify a period of time between consecutive GC cycles. When there is a
+	significant amount of route withdraws, GC cycles are executed repeatedly
+	with given period time (with some random factor). When there is just
+	small amount of changes, GC cycles are not executed. In extensive route
+	server setups, running GC on hundreds of full BGP routing tables can
+	take significant amount of time, therefore they should use higher GC
+	periods. Default: adaptive, based on number of routing tables in the
+	configuration. From 10 s (with <= 25 routing tables) up to 600 s (with
+	>= 1500 routing tables).
+
+	<tag><label id="rtable-cork-threshold">cork threshold <m/number/ <m/number/</tag>
+	Too many pending exports may lead to memory bloating. In such cases,
+        BIRD tries to relieve the memory pressure by pausing some routines until
+        the queue sizes get low enough. This option allows the user to set the
+        thresholds; first value is the low threshold (when to resume), the
+        second one is the high threshold (when to pause). The higher is the
+        threshold, the more memory can get used. In most cases, the defaults
+	should work for you. Default: 128, 512.
 </descrip>
 
 
@@ -1247,8 +1271,8 @@ this:
 
 <code>
 filter not_too_far
-int var;
 {
+	int var;
 	if defined( rip_metric ) then
 		var = rip_metric;
 	else {
@@ -1277,9 +1301,9 @@ local variables. Recursion is not allowed. Function definitions look like this:
 
 <code>
 function name ()
-int local_variable;
 {
-	local_variable = 5;
+	int local_variable;
+	int another_variable = 5;
 }
 
 function with_parameters (int parameter)
@@ -1288,16 +1312,19 @@ function with_parameters (int parameter)
 }
 </code>
 
-<p>Unlike in C, variables are declared after the <cf/function/ line, but before
-the first <cf/{/. You can't declare variables in nested blocks. Functions are
-called like in C: <cf>name(); with_parameters(5);</cf>. Function may return
-values using the <cf>return <m/[expr]/</cf> command. Returning a value exits
-from current function (this is similar to C).
+<p>Like in C programming language, variables are declared inside function body,
+either at the beginning, or mixed with other statements. Declarations may
+contain initialization. You can also declare variables in nested blocks, such
+variables have scope restricted to such block. There is a deprecated syntax to
+declare variables after the <cf/function/ line, but before the first <cf/{/.
+Functions are called like in C: <cf>name(); with_parameters(5);</cf>. Function
+may return values using the <cf>return <m/[expr]/</cf> command. Returning a
+value exits from current function (this is similar to C).
 
-<p>Filters are defined in a way similar to functions except they can't have
+<p>Filters are defined in a way similar to functions except they cannot have
 explicit parameters. They get a route table entry as an implicit parameter, it
 is also passed automatically to any functions called. The filter must terminate
-with either <cf/accept/ or <cf/reject/ statement. If there's a runtime error in
+with either <cf/accept/ or <cf/reject/ statement. If there is a runtime error in
 filter, the route is rejected.
 
 <p>A nice trick to debug filters is to use <cf>show route filter <m/name/</cf>
@@ -1667,7 +1694,8 @@ prefix and an ASN as arguments.
 <sect>Control structures
 <label id="control-structures">
 
-<p>Filters support two control structures: conditions and case switches.
+<p>Filters support several control structures: conditions, for loops and case
+switches.
 
 <p>Syntax of a condition is: <cf>if <M>boolean expression</M> then <m/commandT/;
 else <m/commandF/;</cf> and you can use <cf>{ <m/command1/; <m/command2/;
@@ -1675,6 +1703,14 @@ else <m/commandF/;</cf> and you can use <cf>{ <m/command1/; <m/command2/;
 omitted. If the <cf><m>boolean expression</m></cf> is true, <m/commandT/ is
 executed, otherwise <m/commandF/ is executed.
 
+<p>For loops allow to iterate over elements in compound data like BGP paths or
+community lists. The syntax is: <cf>for [ <m/type/ ] <m/variable/ in <m/expr/
+do <m/command/;</cf> and you can also use compound command like in conditions.
+The expression is evaluated to a compound data, then for each element from such
+data the command is executed with the item assigned to the variable. A variable
+may be an existing one (when just name is used) or a locally defined (when type
+and name is used). In both cases, it must have the same type as elements.
+
 <p>The <cf>case</cf> is similar to case from Pascal. Syntax is <cf>case
 <m/expr/ { else: | <m/num_or_prefix [ .. num_or_prefix]/: <m/statement/ ; [
 ... ] }</cf>. The expression after <cf>case</cf> can be of any type which can be
@@ -1687,16 +1723,21 @@ neither of the <cf/:/ clauses, the statements after <cf/else:/ are executed.
 <p>Here is example that uses <cf/if/ and <cf/case/ structures:
 
 <code>
+if 1234 = i then printn "."; else {
+	print "not 1234";
+	print "You need {} around multiple commands";
+}
+
+for int asn in bgp_path do {
+	printn "ASN: ", asn;
+	if asn < 65536 then print " (2B)"; else print " (4B)";
+}
+
 case arg1 {
 	2: print "two"; print "I can do more commands without {}";
 	3 .. 5: print "three to five";
 	else: print "something else";
 }
-
-if 1234 = i then printn "."; else {
-  print "not 1234";
-  print "You need {} around multiple commands";
-}
 </code>
 
 
diff --git a/filter/config.Y b/filter/config.Y
index 8cecf936..5ba4f7e6 100644
--- a/filter/config.Y
+++ b/filter/config.Y
@@ -32,6 +32,36 @@ static inline u32 pair_b(u32 p) { return p & 0xFFFF; }
   f_new_inst(FI_EA_SET, f_new_inst(fi_code, f_new_inst(FI_DEFAULT, f_new_inst(FI_EA_GET, da), f_new_inst(FI_CONSTANT, (struct f_val) { .type = T_INT, .val.i = def })), arg), da)
   
 
+static int
+f_new_var(struct sym_scope *s)
+{
+  /*
+   * - A variable is an offset on vstack from vbase.
+   * - Vbase is set on filter start / function call.
+   * - Scopes contain anonymous scopes (blocks) inside filter/function scope
+   * - Each scope knows number of vars in that scope
+   * - Offset is therefore a sum of 'slots' up to named scope
+   * - New variables are added on top of vstk, so intermediate values cannot
+   *   be there during FI_VAR_INIT. I.e. no 'var' inside 'term'.
+   * - Also, each f_line must always have its scope, otherwise a variable may
+   *   be defined but not initialized if relevant f_line is not executed.
+   */
+
+  int offset = s->slots++;
+
+  while (!s->name)
+  {
+    s = s->next;
+    ASSERT(s);
+    offset += s->slots;
+  }
+
+  if (offset >= 0xff)
+    cf_error("Too many variables, at most 255 allowed");
+
+  return offset;
+}
+
 /*
  * Sets and their items are during parsing handled as lists, linked
  * through left ptr. The first item in a list also contains a pointer
@@ -276,7 +306,7 @@ assert_assign(struct f_lval *lval, struct f_inst *expr, const char *start, const
 
   checker = f_new_inst(FI_EQ, expr, getter);
   setter->next = checker;
-  
+
   return assert_done(setter, start, end);
 }
 
@@ -287,6 +317,7 @@ CF_KEYWORDS(FUNCTION, PRINT, PRINTN, UNSET, RETURN,
 	INT, BOOL, IP, TYPE, PREFIX, RD, PAIR, QUAD, EC, LC,
 	SET, STRING, BGPMASK, BGPPATH, CLIST, ECLIST, LCLIST,
 	IF, THEN, ELSE, CASE,
+	FOR, IN, DO,
 	TRUE, FALSE, RT, RO, UNKNOWN, GENERIC,
 	FROM, GW, NET, MASK, PROTO, SCOPE, DEST, IFNAME, IFINDEX, WEIGHT, GW_MPLS,
 	ROA_CHECK, ASN, SRC, DST,
@@ -305,21 +336,23 @@ CF_KEYWORDS(FUNCTION, PRINT, PRINTN, UNSET, RETURN,
 %nonassoc ELSE
 
 %type <xp> cmds_int cmd_prep
-%type <x> term block cmd cmds constant constructor print_list var_list function_call symbol_value bgp_path_expr bgp_path bgp_path_tail
+%type <x> term cmd cmd_var cmds cmds_scoped constant constructor print_list var var_init var_list function_call symbol_value bgp_path_expr bgp_path bgp_path_tail
 %type <fsa> static_attr
 %type <fab> attr_bit
 %type <f> filter where_filter
 %type <fl> filter_body function_body
 %type <flv> lvalue
-%type <i> type function_args function_vars
+%type <i> type function_vars
+%type <fa> function_argsn function_args
 %type <ecs> ec_kind
-%type <fret> break_command 
+%type <fret> break_command
 %type <i32> cnum
 %type <e> pair_item ec_item lc_item set_item switch_item set_items switch_items switch_body
 %type <trie> fprefix_set
 %type <v> set_atom switch_atom fipa
 %type <px> fprefix
 %type <t> get_cf_position
+%type <s> for_var
 
 CF_GRAMMAR
 
@@ -343,7 +376,7 @@ filter_def:
 
 conf: filter_eval ;
 filter_eval:
-   EVAL term { f_eval_int(f_linearize($2)); }
+   EVAL term { f_eval_int(f_linearize($2, 1)); }
  ;
 
 conf: custom_attr ;
@@ -425,25 +458,28 @@ type:
  ;
 
 function_argsn:
-   /* EMPTY */
+   /* EMPTY */ { $$ = NULL; }
  | function_argsn type symbol ';' {
      if ($3->scope->slots >= 0xfe) cf_error("Too many declarations, at most 255 allowed");
-     cf_define_symbol($3, SYM_VARIABLE | $2, offset, $3->scope->slots++);
+     $$ = cfg_alloc(sizeof(struct f_arg));
+     $$->arg = cf_define_symbol($3, SYM_VARIABLE | $2, offset, sym_->scope->slots++);
+     $$->next = $1;
    }
  ;
 
 function_args:
-   '(' ')' { $$ = 0; }
+   '(' ')' { $$ = NULL; }
  | '(' function_argsn type symbol ')' {
-     cf_define_symbol($4, SYM_VARIABLE | $3, offset, $4->scope->slots++);
-     $$ = $4->scope->slots;
+     $$ = cfg_alloc(sizeof(struct f_arg));
+     $$->arg = cf_define_symbol($4, SYM_VARIABLE | $3, offset, sym_->scope->slots++);
+     $$->next = $2;
    }
  ;
 
 function_vars:
    /* EMPTY */ { $$ = 0; }
  | function_vars type symbol ';' {
-     cf_define_symbol($3, SYM_VARIABLE | $2, offset, $3->scope->slots++);
+     cf_define_symbol($3, SYM_VARIABLE | $2, offset, f_new_var(sym_->scope));
      $$ = $1 + 1;
    }
  ;
@@ -471,20 +507,35 @@ where_filter:
 
 function_body:
    function_vars '{' cmds '}' {
-     $$ = f_linearize($3);
+     $$ = f_linearize($3, 0);
      $$->vars = $1;
    }
  ;
 
 conf: function_def ;
 function_def:
-   FUNCTION symbol { DBG( "Beginning of function %s\n", $2->name );
+   FUNCTION symbol {
+     DBG( "Beginning of function %s\n", $2->name );
      $2 = cf_define_symbol($2, SYM_FUNCTION, function, NULL);
      cf_push_scope($2);
-   } function_args function_body {
-     DBG("Definition of function %s with %u args and %u local vars.\n", $2->name, $4, $5->vars);
-     $5->args = $4;
-     $2->function = $5;
+   } function_args {
+     /* Make dummy f_line for storing function prototype */
+     struct f_line *dummy = cfg_allocz(sizeof(struct f_line));
+     $2->function = dummy;
+
+     /* Revert the args */
+     while ($4) {
+       struct f_arg *tmp = $4;
+       $4 = $4->next;
+
+       tmp->next = dummy->arg_list;
+       dummy->arg_list = tmp;
+       dummy->args++;
+     }
+   } function_body {
+     $6->args = $2->function->args;
+     $6->arg_list = $2->function->arg_list;
+     $2->function = $6;
      cf_pop_scope();
    }
  ;
@@ -495,7 +546,11 @@ cmds: /* EMPTY */ { $$ = NULL; }
  | cmds_int { $$ = $1.begin; }
  ;
 
-cmd_prep: cmd {
+cmds_scoped: { cf_push_soft_scope(); } cmds { cf_pop_soft_scope(); $$ = $2; } ;
+
+cmd_var: var | cmd ;
+
+cmd_prep: cmd_var {
   $$.begin = $$.end = $1;
   if ($1)
     while ($$.end->next)
@@ -517,15 +572,6 @@ cmds_int: cmd_prep
  }
  ;
 
-block:
-   cmd {
-     $$=$1;
-   }
- | '{' cmds '}' {
-     $$=$2;
-   }
- ;
-
 /*
  * Complex types, their bison value is struct f_val
  */
@@ -549,7 +595,7 @@ set_atom:
  | VPN_RD { $$.type = T_RD; $$.val.ec = $1; }
  | ENUM   { $$.type = pair_a($1); $$.val.i = pair_b($1); }
  | '(' term ')' {
-     if (f_eval(f_linearize($2), &($$)) > F_RETURN) cf_error("Runtime error");
+     if (f_eval(f_linearize($2, 1), &($$)) > F_RETURN) cf_error("Runtime error");
      if (!f_valid_set_type($$.type)) cf_error("Set-incompatible type");
    }
  | symbol_known {
@@ -561,13 +607,13 @@ set_atom:
 
 switch_atom:
    NUM   { $$.type = T_INT; $$.val.i = $1; }
- | '(' term ')' { $$.type = T_INT; $$.val.i = f_eval_int(f_linearize($2)); }
+ | '(' term ')' { $$.type = T_INT; $$.val.i = f_eval_int(f_linearize($2, 1)); }
  | fipa  { $$ = $1; }
  | ENUM  { $$.type = pair_a($1); $$.val.i = pair_b($1); }
  ;
 
 cnum:
-   term { $$ = f_eval_int(f_linearize($1)); }
+   term { $$ = f_eval_int(f_linearize($1, 1)); }
 
 pair_item:
    '(' cnum ',' cnum ')'		{ $$ = f_new_pair_item($2, $2, $4, $4); }
@@ -651,19 +697,19 @@ fprefix_set:
  ;
 
 switch_body: /* EMPTY */ { $$ = NULL; }
- | switch_body switch_items ':' cmds  {
+ | switch_body switch_items ':' cmds_scoped  {
      /* Fill data fields */
      struct f_tree *t;
-     struct f_line *line = f_linearize($4);
+     struct f_line *line = f_linearize($4, 0);
      for (t = $2; t; t = t->left)
        t->data = line;
      $$ = f_merge_items($1, $2);
    }
- | switch_body ELSECOL cmds {
+ | switch_body ELSECOL cmds_scoped {
      struct f_tree *t = f_new_tree();
      t->from.type = t->to.type = T_VOID;
      t->right = t;
-     t->data = f_linearize($3);
+     t->data = f_linearize($3, 0);
      $$ = f_merge_items($1, t);
  }
  ;
@@ -680,6 +726,7 @@ bgp_path:
 bgp_path_tail:
    NUM bgp_path_tail		{ $$ = f_new_inst(FI_CONSTANT, (struct f_val) { .type = T_PATH_MASK_ITEM, .val.pmi = { .asn = $1, .kind = PM_ASN, }, }); $$->next = $2;  }
  | NUM DDOT NUM bgp_path_tail	{ $$ = f_new_inst(FI_CONSTANT, (struct f_val) { .type = T_PATH_MASK_ITEM, .val.pmi = { .from = $1, .to = $3, .kind = PM_ASN_RANGE }, }); $$->next = $4; }
+ | '[' ']' bgp_path_tail { $$ = f_new_inst(FI_CONSTANT, (struct f_val) { .type = T_PATH_MASK_ITEM, .val.pmi = { .set = NULL, .kind = PM_ASN_SET }, }); $$->next = $3; }
  | '[' set_items ']' bgp_path_tail {
    if ($2->from.type != T_INT) cf_error("Only integer sets allowed in path mask");
    $$ = f_new_inst(FI_CONSTANT, (struct f_val) { .type = T_PATH_MASK_ITEM, .val.pmi = { .set = build_tree($2), .kind = PM_ASN_SET }, }); $$->next = $4;
@@ -699,6 +746,7 @@ constant:
  | fipa	  { $$ = f_new_inst(FI_CONSTANT, $1); }
  | VPN_RD { $$ = f_new_inst(FI_CONSTANT, (struct f_val) { .type = T_RD, .val.ec = $1, }); }
  | net_   { $$ = f_new_inst(FI_CONSTANT, (struct f_val) { .type = T_NET, .val.net = $1, }); }
+ | '[' ']' { $$ = f_new_inst(FI_CONSTANT, (struct f_val) { .type = T_SET, .val.t = NULL, }); }
  | '[' set_items ']' {
      DBG( "We've got a set here..." );
      $$ = f_new_inst(FI_CONSTANT, (struct f_val) { .type = T_SET, .val.t = build_tree($2), });
@@ -722,27 +770,22 @@ var_list: /* EMPTY */ { $$ = NULL; }
  | var_list ',' term { $$ = $3; $$->next = $1; }
 
 function_call:
-   symbol_known '(' var_list ')' {
+   symbol_known '(' var_list ')'
+   {
      if ($1->class != SYM_FUNCTION)
        cf_error("You can't call something which is not a function. Really.");
 
-     struct f_inst *fc = f_new_inst(FI_CALL, $1);
-     uint args = 0;
+     /* Revert the var_list */
+     struct f_inst *args = NULL;
      while ($3) {
-       args++;
-       struct f_inst *tmp = $3->next;
-       $3->next = fc;
+       struct f_inst *tmp = $3;
+       $3 = $3->next;
 
-       fc = $3;
-       $3 = tmp;
+       tmp->next = args;
+       args = tmp;
      }
 
-     if (args != $1->function->args)
-       cf_error("Function call '%s' got %u arguments, need %u arguments.",
-	   $1->name, args, $1->function->args);
-
-     $$ = f_new_inst(FI_CONSTANT, (struct f_val) { .type = T_VOID });
-     $$->next = fc;
+     $$ = f_new_inst(FI_CALL, args, $1);
    }
  ;
 
@@ -866,13 +909,44 @@ print_list: /* EMPTY */ { $$ = NULL; }
    }
  ;
 
+var_init:
+   /* empty */ { $$ = f_new_inst(FI_CONSTANT, (struct f_val) { }); }
+ | '=' term { $$ = $2; }
+ ;
+
+var:
+   type symbol var_init ';' {
+     struct symbol *sym = cf_define_symbol($2, SYM_VARIABLE | $1, offset, f_new_var(sym_->scope));
+     $$ = f_new_inst(FI_VAR_INIT, $3, sym);
+   }
+
+for_var:
+   type symbol { $$ = cf_define_symbol($2, SYM_VARIABLE | $1, offset, f_new_var(sym_->scope)); }
+ | CF_SYM_KNOWN { $$ = $1; cf_assert_symbol($1, SYM_VARIABLE); }
+ ;
+
 cmd:
-   IF term THEN block {
+   '{' cmds_scoped '}' {
+     $$ = $2;
+   }
+ | IF term THEN cmd {
      $$ = f_new_inst(FI_CONDITION, $2, $4, NULL);
    }
- | IF term THEN block ELSE block {
+ | IF term THEN cmd ELSE cmd {
      $$ = f_new_inst(FI_CONDITION, $2, $4, $6);
    }
+ | FOR {
+     /* Reserve space for walk data on stack */
+     cf_push_scope(NULL);
+     conf_this_scope->slots += 2;
+   } for_var IN
+   /* Parse term in the parent scope */
+   { conf_this_scope->active = 0; } term { conf_this_scope->active = 1; }
+   DO cmd {
+     cf_pop_scope();
+     $$ = f_new_inst(FI_FOR_INIT, $6, $3);
+     $$->next = f_new_inst(FI_FOR_NEXT, $3, $9);
+   }
  | symbol_known '=' term ';' {
      switch ($1->class) {
        case SYM_VARIABLE_RANGE:
@@ -929,7 +1003,7 @@ cmd:
  | PRINTN print_list ';' {
     $$ = f_new_inst(FI_PRINT, $2);
    }
- | function_call ';' { $$ = f_new_inst(FI_DROP_RESULT, $1); } 
+ | function_call ';' { $$ = f_new_inst(FI_DROP_RESULT, $1); }
  | CASE term '{' switch_body '}' {
       $$ = f_new_inst(FI_SWITCH, $2, build_tree($4));
    }
diff --git a/filter/data.c b/filter/data.c
index 9dab1915..d26b07f5 100644
--- a/filter/data.c
+++ b/filter/data.c
@@ -71,6 +71,7 @@ btype
 f_type_element_type(btype t)
 {
   switch(t) {
+    case T_PATH:   return T_INT;
     case T_CLIST:  return T_PAIR;
     case T_ECLIST: return T_EC;
     case T_LCLIST: return T_LC;
@@ -78,6 +79,8 @@ f_type_element_type(btype t)
   };
 }
 
+const struct f_trie f_const_empty_trie = { .ipv4 = -1, };
+
 const struct f_val f_const_empty_path = {
   .type = T_PATH,
   .val.ad = &null_adata,
@@ -90,6 +93,9 @@ const struct f_val f_const_empty_path = {
 }, f_const_empty_lclist = {
   .type = T_LCLIST,
   .val.ad = &null_adata,
+}, f_const_empty_prefix_set = {
+  .type = T_PREFIX_SET,
+  .val.ti = &f_const_empty_trie,
 };
 
 static void
@@ -178,7 +184,7 @@ val_compare(const struct f_val *v1, const struct f_val *v2)
     if (val_is_ip4(v1) && (v2->type == T_QUAD))
       return uint_cmp(ipa_to_u32(v1->val.ip), v2->val.i);
 
-    debug( "Types do not match in val_compare\n" );
+    DBG( "Types do not match in val_compare\n" );
     return F_CMP_ERROR;
   }
 
@@ -292,6 +298,12 @@ val_same(const struct f_val *v1, const struct f_val *v2)
 int
 clist_set_type(const struct f_tree *set, struct f_val *v)
 {
+  if (!set)
+  {
+    v->type = T_VOID;
+    return 1;
+  }
+
   switch (set->from.type)
   {
   case T_PAIR:
@@ -528,6 +540,9 @@ val_in_range(const struct f_val *v1, const struct f_val *v2)
   if (v2->type != T_SET)
     return F_CMP_ERROR;
 
+  if (!v2->val.t)
+    return 0;
+
   /* With integrated Quad<->IP implicit conversion */
   if ((v1->type == v2->val.t->from.type) ||
       ((v1->type == T_QUAD) && val_is_ip4(&(v2->val.t->from)) && val_is_ip4(&(v2->val.t->to))))
diff --git a/filter/data.h b/filter/data.h
index 23db4a85..c1e7c736 100644
--- a/filter/data.h
+++ b/filter/data.h
@@ -209,9 +209,11 @@ int val_in_range(const struct f_val *v1, const struct f_val *v2);
 
 int clist_set_type(const struct f_tree *set, struct f_val *v);
 static inline int eclist_set_type(const struct f_tree *set)
-{ return set->from.type == T_EC; }
+{ return !set || set->from.type == T_EC; }
 static inline int lclist_set_type(const struct f_tree *set)
-{ return set->from.type == T_LC; }
+{ return !set || set->from.type == T_LC; }
+static inline int path_set_type(const struct f_tree *set)
+{ return !set || set->from.type == T_INT; }
 
 const struct adata *clist_filter(struct linpool *pool, const struct adata *list, const struct f_val *set, int pos);
 const struct adata *eclist_filter(struct linpool *pool, const struct adata *list, const struct f_val *set, int pos);
@@ -227,7 +229,7 @@ undef_value(struct f_val v)
     (v.val.ad == &null_adata);
 }
 
-extern const struct f_val f_const_empty_path, f_const_empty_clist, f_const_empty_eclist, f_const_empty_lclist;
+extern const struct f_val f_const_empty_path, f_const_empty_clist, f_const_empty_eclist, f_const_empty_lclist, f_const_empty_prefix_set;
 static inline const struct f_val *f_get_empty(btype t)
 {
   switch (t) {
diff --git a/filter/decl.m4 b/filter/decl.m4
index c59cd7f3..e2472127 100644
--- a/filter/decl.m4
+++ b/filter/decl.m4
@@ -191,6 +191,12 @@ if (f$1->type && f$2->type && (f$1->type != f$2->type) &&
   cf_error("Arguments $1 and $2 of %s must be of the same type", f_instruction_name(what->fi_code));
 FID_INTERPRET_BODY()')
 
+m4_define(ARG_PREFER_SAME_TYPE, `
+FID_NEW_BODY()m4_dnl
+if (f$1->type && f$2->type && (f$1->type != f$2->type))
+   (void) (f_const_promotion(f$2, f$1->type) || f_const_promotion(f$1, f$2->type));
+FID_INTERPRET_BODY()')
+
 #	Executing another filter line. This replaces the recursion
 #	that was needed in the former implementation.
 m4_define(LINEX, `FID_INTERPRET_EXEC()LINEX_($1)FID_INTERPRET_NEW()return $1 FID_INTERPRET_BODY()')
@@ -216,7 +222,7 @@ whati->f$1 = f$1;
 FID_DUMP_BODY()m4_dnl
 f_dump_line(item->fl$1, indent + 1);
 FID_LINEARIZE_BODY()m4_dnl
-item->fl$1 = f_linearize(whati->f$1);
+item->fl$1 = f_linearize(whati->f$1, $2);
 FID_SAME_BODY()m4_dnl
 if (!f_same(f1->fl$1, f2->fl$1)) return 0;
 FID_ITERATE_BODY()m4_dnl
@@ -244,9 +250,13 @@ m4_define(ERROR,
 #	This macro specifies result type and makes there are no conflicting definitions
 m4_define(RESULT_TYPE,
 	`m4_ifdef([[INST_RESULT_TYPE]],
-		  [[m4_ifelse(INST_RESULT_TYPE,$1,,[[ERROR([[Multiple type definitons]])]])]],
+		  [[m4_ifelse(INST_RESULT_TYPE,$1,,[[ERROR([[Multiple type definitions in]] INST_NAME)]])]],
 		  [[m4_define(INST_RESULT_TYPE,$1) RESULT_TYPE_($1)]])')
 
+m4_define(RESULT_TYPE_CHECK,
+	`m4_ifelse(INST_OUTVAL,0,,
+		   [[m4_ifdef([[INST_RESULT_TYPE]],,[[ERROR([[Missing type definition in]] INST_NAME)]])]])')
+
 m4_define(RESULT_TYPE_, `
 FID_NEW_BODY()m4_dnl
 what->type = $1;
@@ -300,6 +310,7 @@ m4_define(FID_ITERATE, `FID_ZONE(10, Iteration)')
 
 #	This macro does all the code wrapping. See inline comments.
 m4_define(INST_FLUSH, `m4_ifdef([[INST_NAME]], [[
+RESULT_TYPE_CHECK()m4_dnl		 Check for defined RESULT_TYPE()
 FID_ENUM()m4_dnl			 Contents of enum fi_code { ... }
   INST_NAME(),
 FID_ENUM_STR()m4_dnl			 Contents of const char * indexed by enum fi_code
@@ -375,6 +386,7 @@ case INST_NAME(): {
 #undef whati
 #undef item
   dest->items[pos].fi_code = what->fi_code;
+  dest->items[pos].flags = what->flags;
   dest->items[pos].lineno = what->lineno;
   break;
 }
@@ -402,6 +414,7 @@ m4_define(INST, `m4_dnl				This macro is called on beginning of each instruction
 INST_FLUSH()m4_dnl				First, old data is flushed
 m4_define([[INST_NAME]], [[$1]])m4_dnl		Then we store instruction name,
 m4_define([[INST_INVAL]], [[$2]])m4_dnl		instruction input value count,
+m4_define([[INST_OUTVAL]], [[$3]])m4_dnl	instruction output value count,
 m4_undefine([[INST_NEVER_CONSTANT]])m4_dnl	reset NEVER_CONSTANT trigger,
 m4_undefine([[INST_RESULT_TYPE]])m4_dnl		and reset RESULT_TYPE value.
 FID_INTERPRET_BODY()m4_dnl 			By default, every code is interpreter code.
@@ -505,6 +518,11 @@ f_const_promotion(struct f_inst *arg, btype want)
     return 1;
   }
 
+  else if ((c->type == T_SET) && (!c->val.t) && (want == T_PREFIX_SET)) {
+    *c = f_const_empty_prefix_set;
+    return 1;
+  }
+
   return 0;
 }
 
@@ -560,7 +578,7 @@ FID_WR_PUT(8)
 }
 
 struct f_line *
-f_linearize_concat(const struct f_inst * const inst[], uint count)
+f_linearize_concat(const struct f_inst * const inst[], uint count, uint results)
 {
   uint len = 0;
   for (uint i=0; i<count; i++)
@@ -572,6 +590,8 @@ f_linearize_concat(const struct f_inst * const inst[], uint count)
   for (uint i=0; i<count; i++)
     out->len = linearize(out, inst[i], out->len);
 
+    out->results = results;
+
 #ifdef LOCAL_DEBUG
   f_dump_line(out, 0);
 #endif
@@ -640,6 +660,7 @@ FID_WR_PUT(4)m4_dnl
 struct f_inst {
   struct f_inst *next;			/* Next instruction */
   enum f_instruction_code fi_code;	/* Instruction code */
+  enum f_instruction_flags flags;	/* Flags, instruction-specific */
   btype type;				/* Type of returned value, if known */
   int size;				/* How many instructions are underneath */
   int lineno;				/* Line number */
diff --git a/filter/f-inst.c b/filter/f-inst.c
index e7b642ab..fff93517 100644
--- a/filter/f-inst.c
+++ b/filter/f-inst.c
@@ -62,8 +62,9 @@
  *	m4_dnl	INST(FI_NOP, in, out) {			enum value, input args, output args
  *	m4_dnl	  ARG(num, type);			argument, its id (in data fields) and type accessible by v1, v2, v3
  *	m4_dnl	  ARG_ANY(num);				argument with no type check accessible by v1, v2, v3
+ *	m4_dnl	  ARG_TYPE(num, type);			just declare the type of argument
  *	m4_dnl	  VARARG;				variable-length argument list; accessible by vv(i) and whati->varcount
- *	m4_dnl	  LINE(num, unused);			this argument has to be converted to its own f_line
+ *	m4_dnl	  LINE(num, out);			this argument has to be converted to its own f_line
  *	m4_dnl	  SYMBOL;				symbol handed from config
  *	m4_dnl	  STATIC_ATTR;				static attribute definition
  *	m4_dnl	  DYNAMIC_ATTR;				dynamic attribute definition
@@ -80,10 +81,17 @@
  *	m4_dnl	  )
  *
  *	m4_dnl	  RESULT(type, union-field, value);	putting this on value stack
+ *	m4_dnl	  RESULT_(type, union-field, value);	like RESULT(), but do not declare the type
  *	m4_dnl	  RESULT_VAL(value-struct);		pass the struct f_val directly
+ *	m4_dnl	  RESULT_TYPE(type);			just declare the type of result value
  *	m4_dnl	  RESULT_VOID;				return undef
  *	m4_dnl	}
  *
+ *	Note that runtime arguments m4_dnl (ARG*, VARARG) must be defined before
+ *	parse-time arguments m4_dnl (LINE, SYMBOL, ...). During linearization,
+ *	first ones move position in f_line by linearizing arguments first, while
+ *	second ones store data to the current position.
+ *
  *	Also note that the { ... } blocks are not respected by M4 at all.
  *	If you get weird unmatched-brace-pair errors, check what it generated and why.
  *	What is really considered as one instruction is not the { ... } block
@@ -91,6 +99,24 @@
  *
  *	Other code is just copied into the interpreter part.
  *
+ *	The filter language uses a simple type system, where values have types
+ *	(constants T_*) and also terms (instructions) are statically typed. Our
+ *	static typing is partial (some terms do not declare types of arguments
+ *	or results), therefore it can detect most but not all type errors and
+ *	therefore we still have runtime type checks.
+ *
+ *	m4_dnl  Types of arguments are declared by macros ARG() and ARG_TYPE(),
+ *	m4_dnl  types of results are declared by RESULT() and RESULT_TYPE().
+ *	m4_dnl  Macros ARG_ANY(), RESULT_() and RESULT_VAL() do not declare types
+ *	m4_dnl  themselves, but can be combined with ARG_TYPE() / RESULT_TYPE().
+ *
+ *	m4_dnl  Note that types should be declared only once. If there are
+ *	m4_dnl  multiple RESULT() macros in an instruction definition, they must
+ *	m4_dnl  use the exact same expression for type, or they should be replaced
+ *	m4_dnl  by multiple RESULT_() macros and a common RESULT_TYPE() macro.
+ *	m4_dnl  See e.g. FI_EA_GET or FI_MIN instructions.
+ *
+ *
  *	If you are satisfied with this, you don't need to read the following
  *	detailed description of what is really done with the instruction definitions.
  *
@@ -215,6 +241,37 @@
  *
  *	m4_dnl	If you are stymied, see FI_CALL or FI_CONSTANT or just search for
  *	m4_dnl	the mentioned macros in this file to see what is happening there in wild.
+ *
+ *
+ *	A note about soundness of the type system:
+ *
+ *	A type system is sound when types of expressions are consistent with
+ *	types of values resulting from evaluation of such expressions. Untyped
+ *	expressions are ok, but badly typed expressions are not sound. So is
+ *	the type system of BIRD filtering code sound? There are some points:
+ *
+ *	All cases of (one) m4_dnl RESULT() macro are obviously ok, as the macro
+ *	both declares a type and returns a value. One have to check instructions
+ *	that use m4_dnl RESULT_TYPE() macro. There are two issues:
+ *
+ *	FI_AND, FI_OR - second argument is statically checked to be T_BOOL and
+ *	passed as result without dynamic typecheck, declared to be T_BOOL. If
+ *	an untyped non-bool expression is used as a second argument, then
+ *	the mismatched type is returned.
+ *
+ *	FI_VAR_GET - soundness depends on consistency of declared symbol types
+ *	and stored values. This is maintained when values are stored by
+ *	FI_VAR_SET, but when they are stored by FI_CALL, only static checking is
+ *	used, so when an untyped expression returning mismatched value is used
+ *	as a function argument, then inconsistent value is stored and subsequent
+ *	FI_VAR_GET would be unsound.
+ *
+ *	Both of these issues are inconsequential, as mismatched values from
+ *	unsound expressions will be caught by dynamic typechecks like mismatched
+ *	values from untyped expressions.
+ *
+ *	Also note that FI_CALL is the only expression without properly declared
+ *	result type.
  */
 
 /* Binary operators */
@@ -255,7 +312,7 @@
     RESULT_TYPE(T_BOOL);
 
     if (v1.val.i)
-      LINE(2,0);
+      LINE(2,1);
     else
       RESULT_VAL(v1);
   }
@@ -265,7 +322,7 @@
     RESULT_TYPE(T_BOOL);
 
     if (!v1.val.i)
-      LINE(2,0);
+      LINE(2,1);
     else
       RESULT_VAL(v1);
   }
@@ -358,7 +415,7 @@
 	  break;
 
 	case T_SET:
-	  if (vv(i).val.t->from.type != T_INT)
+	  if (!path_set_type(vv(i).val.t))
 	    runtime("Only integer sets allowed in path mask");
 
 	  pm->item[i] = (struct f_path_mask_item) {
@@ -380,12 +437,14 @@
   INST(FI_NEQ, 2, 1) {
     ARG_ANY(1);
     ARG_ANY(2);
+    ARG_PREFER_SAME_TYPE(1, 2);
     RESULT(T_BOOL, i, !val_same(&v1, &v2));
   }
 
   INST(FI_EQ, 2, 1) {
     ARG_ANY(1);
     ARG_ANY(2);
+    ARG_PREFER_SAME_TYPE(1, 2);
     RESULT(T_BOOL, i, val_same(&v1, &v2));
   }
 
@@ -456,6 +515,18 @@
     RESULT(T_BOOL, i, ipa_is_ip4(v1.val.ip));
   }
 
+  INST(FI_VAR_INIT, 1, 0) {
+    NEVER_CONSTANT;
+    ARG_ANY(1);
+    SYMBOL;
+    ARG_TYPE(1, sym->class & 0xff);
+
+    /* New variable is always the last on stack */
+    uint pos = curline.vbase + sym->offset;
+    fstk->vstk[pos] = v1;
+    fstk->vcnt = pos + 1;
+  }
+
   /* Set to indirect value prepared in v1 */
   INST(FI_VAR_SET, 1, 0) {
     NEVER_CONSTANT;
@@ -486,12 +557,100 @@
     RESULT_VAL(val);
   }
 
+  INST(FI_FOR_INIT, 1, 0) {
+    NEVER_CONSTANT;
+    ARG_ANY(1);
+    SYMBOL;
+
+    FID_NEW_BODY()
+    ASSERT((sym->class & ~0xff) == SYM_VARIABLE);
+
+    /* Static type check */
+    if (f1->type)
+    {
+      enum btype t_var = (sym->class & 0xff);
+      enum btype t_arg = f_type_element_type(f1->type);
+      if (!t_arg)
+        cf_error("Value of expression in FOR must be iterable, got %s",
+		 f_type_name(f1->type));
+      if (t_var != t_arg)
+	cf_error("Loop variable '%s' in FOR must be %s, is %s",
+		 sym->name, f_type_name(t_arg), f_type_name(t_var));
+    }
+
+    FID_INTERPRET_BODY()
+
+    /* Dynamic type check */
+    if ((sym->class & 0xff) != f_type_element_type(v1.type))
+      runtime("Mismatched argument and variable type");
+
+    /* Setup the index */
+    v2 = (struct f_val) { .type = T_INT, .val.i = 0 };
+
+    /* Keep v1 and v2 on the stack */
+    fstk->vcnt += 2;
+  }
+
+  INST(FI_FOR_NEXT, 2, 0) {
+    NEVER_CONSTANT;
+    SYMBOL;
+
+    /* Type checks are done in FI_FOR_INIT */
+
+    /* Loop variable */
+    struct f_val *var = &fstk->vstk[curline.vbase + sym->offset];
+    int step = 0;
+
+    switch(v1.type)
+    {
+    case T_PATH:
+      var->type = T_INT;
+      step = as_path_walk(v1.val.ad, &v2.val.i, &var->val.i);
+      break;
+
+    case T_CLIST:
+      var->type = T_PAIR;
+      step = int_set_walk(v1.val.ad, &v2.val.i, &var->val.i);
+      break;
+
+    case T_ECLIST:
+      var->type = T_EC;
+      step = ec_set_walk(v1.val.ad, &v2.val.i, &var->val.ec);
+      break;
+
+    case T_LCLIST:
+      var->type = T_LC;
+      step = lc_set_walk(v1.val.ad, &v2.val.i, &var->val.lc);
+      break;
+
+    default:
+      runtime( "Clist or lclist expected" );
+    }
+
+    if (step)
+    {
+      /* Keep v1 and v2 on the stack */
+      fstk->vcnt += 2;
+
+      /* Repeat this instruction */
+      curline.pos--;
+
+      /* Execute the loop body */
+      LINE(1, 0);
+
+      /* Space for loop variable, may be unused */
+      fstk->vcnt += 1;
+    }
+    else
+      var->type = T_VOID;
+  }
+
   INST(FI_CONDITION, 1, 0) {
     ARG(1, T_BOOL);
     if (v1.val.i)
       LINE(2,0);
     else
-      LINE(3,1);
+      LINE(3,0);
   }
 
   INST(FI_PRINT, 0, 0) {
@@ -771,6 +930,7 @@
   INST(FI_DEFAULT, 2, 1) {
     ARG_ANY(1);
     ARG_ANY(2);
+    RESULT_TYPE(f_type_element_type(v2.type));
 
     log(L_INFO "Type of arg 1 is: %d", v1.type);
 
@@ -945,7 +1105,7 @@
     RESULT(T_INT, i, v1.val.lc.ldp2);
   }
 
-  INST(FI_MIN, 1, 1) {	/* Get minimum element from set */
+  INST(FI_MIN, 1, 1) {	/* Get minimum element from list */
     ARG_ANY(1);
     RESULT_TYPE(f_type_element_type(v1.type));
     switch(v1.type)
@@ -979,7 +1139,7 @@
     }
   }
 
-  INST(FI_MAX, 1, 1) {	/* Get maximum element from set */
+  INST(FI_MAX, 1, 1) {	/* Get maximum element from list */
     ARG_ANY(1);
     RESULT_TYPE(f_type_element_type(v1.type));
     switch(v1.type)
@@ -1013,7 +1173,7 @@
     }
   }
 
-  INST(FI_RETURN, 1, 1) {
+  INST(FI_RETURN, 1, 0) {
     NEVER_CONSTANT;
     /* Acquire the return value */
     ARG_ANY(1);
@@ -1041,28 +1201,59 @@
 
   INST(FI_CALL, 0, 1) {
     NEVER_CONSTANT;
+    VARARG;
     SYMBOL;
 
+    /* Fake result type declaration */
+    RESULT_TYPE(T_VOID);
+
+    FID_NEW_BODY()
+    ASSERT(sym->class == SYM_FUNCTION);
+
+    if (whati->varcount != sym->function->args)
+      cf_error("Function '%s' expects %u arguments, got %u arguments",
+	       sym->name, sym->function->args, whati->varcount);
+
+    /* Typecheck individual arguments */
+    struct f_inst *a = fvar;
+    struct f_arg *b = sym->function->arg_list;
+    for (uint i = 1; a && b; a = a->next, b = b->next, i++)
+    {
+      enum btype b_type = b->arg->class & 0xff;
+
+      if (a->type && (a->type != b_type) && !f_const_promotion(a, b_type))
+	cf_error("Argument %u of '%s' must be %s, got %s",
+		 i, sym->name, f_type_name(b_type), f_type_name(a->type));
+    }
+    ASSERT(!a && !b);
+
+    /* Add implicit void slot for the return value */
+    struct f_inst *tmp = f_new_inst(FI_CONSTANT, (struct f_val) { .type = T_VOID });
+    tmp->next = whati->fvar;
+    whati->fvar = tmp;
+    what->size += tmp->size;
+
+    /* Mark recursive calls, they have dummy f_line */
+    if (!sym->function->len)
+      what->flags |= FIF_RECURSIVE;
+
     FID_SAME_BODY()
-      if (!(f1->sym->flags & SYM_FLAG_SAME))
-	return 0;
+    if (!(f1->sym->flags & SYM_FLAG_SAME) && !(f1_->flags & FIF_RECURSIVE))
+      return 0;
 
     FID_ITERATE_BODY()
+    if (!(what->flags & FIF_RECURSIVE))
       BUFFER_PUSH(fit->lines) = whati->sym->function;
 
     FID_INTERPRET_BODY()
 
     /* Push the body on stack */
     LINEX(sym->function);
+    curline.vbase = curline.ventry;
     curline.emask |= FE_RETURN;
 
-    /* Before this instruction was called, there was the T_VOID
-     * automatic return value pushed on value stack and also
-     * sym->function->args function arguments. Setting the
-     * vbase to point to first argument. */
-    ASSERT(curline.ventry >= sym->function->args);
-    curline.ventry -= sym->function->args;
-    curline.vbase = curline.ventry;
+    /* Arguments on stack */
+    fstk->vcnt += sym->function->args;
 
     /* Storage for local variables */
     f_vcnt_check_overflow(sym->function->vars);
@@ -1176,17 +1367,10 @@
 
     if (v1.type == T_PATH)
     {
-      const struct f_tree *set = NULL;
-      u32 key = 0;
-
-      if (v2.type == T_INT)
-	key = v2.val.i;
-      else if ((v2.type == T_SET) && (v2.val.t->from.type == T_INT))
-	set = v2.val.t;
+      if ((v2.type == T_SET) && path_set_type(v2.val.t) || (v2.type == T_INT))
+	RESULT_(T_PATH, ad, [[ as_path_filter(fpool, v1.val.ad, &v2, 0) ]]);
       else
 	runtime("Can't delete non-integer (set)");
-
-      RESULT_(T_PATH, ad, [[ as_path_filter(fpool, v1.val.ad, set, key, 0) ]]);
     }
 
     else if (v1.type == T_CLIST)
@@ -1238,10 +1422,8 @@
 
     if (v1.type == T_PATH)
     {
-      u32 key = 0;
-
-      if ((v2.type == T_SET) && (v2.val.t->from.type == T_INT))
-	RESULT_(T_PATH, ad, [[ as_path_filter(fpool, v1.val.ad, v2.val.t, key, 1) ]]);
+      if ((v2.type == T_SET) && path_set_type(v2.val.t))
+	RESULT_(T_PATH, ad, [[ as_path_filter(fpool, v1.val.ad, &v2, 1) ]]);
       else
 	runtime("Can't filter integer");
     }
@@ -1301,7 +1483,7 @@
 
   }
 
-  INST(FI_FORMAT, 1, 0) {	/* Format */
+  INST(FI_FORMAT, 1, 1) {	/* Format */
     ARG_ANY(1);
     RESULT(T_STRING, s, val_format_str(fpool, &v1));
   }
diff --git a/filter/f-inst.h b/filter/f-inst.h
index 047a66c9..fbc59de7 100644
--- a/filter/f-inst.h
+++ b/filter/f-inst.h
@@ -22,7 +22,7 @@
 
 /* Flags for instructions */
 enum f_instruction_flags {
-  FIF_PRINTED = 1,		/* FI_PRINT_AND_DIE: message put in buffer */
+  FIF_RECURSIVE = 1,		/* FI_CALL: function is directly recursive */
 } PACKED;
 
 /* Include generated filter instruction declarations */
@@ -35,19 +35,26 @@ const char *f_instruction_name_(enum f_instruction_code fi);
 static inline const char *f_instruction_name(enum f_instruction_code fi)
 { return f_instruction_name_(fi) + 3; }
 
+struct f_arg {
+  struct symbol *arg;
+  struct f_arg *next;
+};
+
 /* Filter structures for execution */
 /* Line of instructions to be unconditionally executed one after another */
 struct f_line {
   uint len;				/* Line length */
   u8 args;				/* Function: Args required */
   u8 vars;
+  u8 results;				/* Results left on stack: cmd -> 0, term -> 1 */
+  struct f_arg *arg_list;
   struct f_line_item items[0];		/* The items themselves */
 };
 
 /* Convert the f_inst infix tree to the f_line structures */
-struct f_line *f_linearize_concat(const struct f_inst * const inst[], uint count);
-static inline struct f_line *f_linearize(const struct f_inst *root)
-{ return f_linearize_concat(&root, 1); }
+struct f_line *f_linearize_concat(const struct f_inst * const inst[], uint count, uint results);
+static inline struct f_line *f_linearize(const struct f_inst *root, uint results)
+{ return f_linearize_concat(&root, 1, results); }
 
 void f_dump_line(const struct f_line *, uint indent);
 
diff --git a/filter/f-util.c b/filter/f-util.c
index fb93ee80..82a06bdd 100644
--- a/filter/f-util.c
+++ b/filter/f-util.c
@@ -37,6 +37,6 @@ struct filter *f_new_where(struct f_inst *where)
 				   f_new_inst(FI_DIE, F_REJECT));
 
   struct filter *f = cfg_allocz(sizeof(struct filter));
-  f->root = f_linearize(cond);
+  f->root = f_linearize(cond, 0);
   return f;
 }
diff --git a/filter/filter.c b/filter/filter.c
index ad2fafe2..9a94545c 100644
--- a/filter/filter.c
+++ b/filter/filter.c
@@ -179,8 +179,7 @@ interpret(struct filter_state *fs, const struct f_line *line, struct f_val *val)
     }
 
     /* End of current line. Drop local variables before exiting. */
-    fstk->vcnt -= curline.line->vars;
-    fstk->vcnt -= curline.line->args;
+    fstk->vcnt = curline.ventry + curline.line->results;
     fstk->ecnt--;
   }
 
diff --git a/filter/filter_test.c b/filter/filter_test.c
index 63764964..5b24a765 100644
--- a/filter/filter_test.c
+++ b/filter/filter_test.c
@@ -70,6 +70,7 @@ int
 main(int argc, char *argv[])
 {
   bt_init(argc, argv);
+
   bt_bird_init();
 
   bt_assert_hook = bt_assert_filter;
diff --git a/filter/test.conf b/filter/test.conf
index cd2fa8db..22f5dea3 100644
--- a/filter/test.conf
+++ b/filter/test.conf
@@ -146,9 +146,8 @@ bt_test_same(onef, twof, 0);
  */
 
 function t_bool()
-bool b;
 {
-	b = true;
+	bool b = true;
 	bt_assert(b);
 	bt_assert(!!b);
 
@@ -184,12 +183,11 @@ define xyzzy = (120+10);
 define '1a-a1' = (xyzzy-100);
 
 function t_int()
-int i;
 {
 	bt_assert(xyzzy = 130);
 	bt_assert('1a-a1' = 30);
 
-	i = four;
+	int i = four;
 	i = 12*100 + 60/2 + i;
 	i = (i + 0);
 	bt_assert(i = 1234);
@@ -238,14 +236,19 @@ define is2 = [(17+2), 17, 15, 11, 8, 5, 3, 2];
 define is3 = [5, 17, 2, 11, 8, 15, 3, 19];
 
 function t_int_set()
-int set is;
 {
+	int set is = [];
+	bt_assert(is = []);
+	bt_assert(0 !~ is);
+
 	bt_assert(1 ~ [1,2,3]);
 	bt_assert(5 ~ [1..20]);
 	bt_assert(2 ~ [ 1, 2, 3 ]);
 	bt_assert(5 ~ [ 4 .. 7 ]);
 	bt_assert(1 !~ [ 2, 3, 4 ]);
 	bt_assert(999 !~ [ 666, 333 ]);
+	bt_assert(1 !~ []);
+	bt_assert(1 !~ is);
 
 	is = [ 2, 3, 4, 7..11 ];
 	bt_assert(10 ~ is);
@@ -280,6 +283,7 @@ int set is;
 	bt_assert([1,4..10,20] = [1,4..10,20]);
 
 	bt_assert(format([ 1, 2, 1, 1, 1, 3, 4, 1, 1, 1, 5 ]) = "[1, 1, 1, 1, 1, 1, 1, 2, 3, 4, 5]");
+	bt_assert(format([]) = "[]");
 }
 
 bt_test_suite(t_int_set, "Testing sets of integers");
@@ -293,9 +297,8 @@ bt_test_suite(t_int_set, "Testing sets of integers");
  */
 
 function t_string()
-string st;
 {
-	st = "Hello";
+	string st = "Hello";
 	bt_assert(format(st) = "Hello");
 	bt_assert(st ~ "Hell*");
 	bt_assert(st ~ "?ello");
@@ -320,9 +323,8 @@ function 'mkpair-a'(int a)
 }
 
 function t_pair()
-pair pp;
 {
-	pp = (1, 2);
+	pair pp = (1, 2);
 	bt_assert(format(pp) = "(1,2)");
 	bt_assert((1,2) = pp);
 	bt_assert((1,1+1) = pp);
@@ -343,10 +345,11 @@ bt_test_suite(t_pair, "Testing pairs");
  */
 
 function t_pair_set()
-pair pp;
-pair set ps;
 {
-	pp = (1, 2);
+	pair pp = (1, 2);
+	pair set ps = [];
+	bt_assert(pp !~ ps);
+
 	ps = [(1,(one+one)), (3,4)..(4,8), (5,*), (6,3..6)];
 	bt_assert(format(ps) = "[(1,2), (3,4)..(4,8), (5,0)..(5,65535), (6,3)..(6,6)]");
 	bt_assert(pp ~ ps);
@@ -363,6 +366,7 @@ pair set ps;
 	bt_assert((6,6+one) !~ ps);
 	bt_assert(((one+6),2) !~ ps);
 	bt_assert((1,1) !~ ps);
+	bt_assert(pp !~ []);
 
 	ps = [(20..150, 200..300), (50100..50200, 1000..50000), (*, 5+5)];
 	bt_assert((100,200) ~ ps);
@@ -414,6 +418,7 @@ quad qq;
 	qq = 1.2.3.4;
 	bt_assert(qq ~ [1.2.3.4, 5.6.7.8]);
 	bt_assert(qq !~ [1.2.1.1, 1.2.3.5]);
+	bt_assert(qq !~ []);
 }
 
 bt_test_suite(t_quad_set, "Testing sets of quads");
@@ -494,6 +499,7 @@ ip set ips;
 
 	bt_assert(1.2.3.4 !~ [ 1.2.3.3, 1.2.3.5 ]);
 	bt_assert(1.2.3.4 ~ [ 1.2.3.3..1.2.3.5 ]);
+	bt_assert(1.2.3.4 !~ []);
 }
 
 bt_test_suite(t_ip_set, "Testing sets of ip address");
@@ -582,13 +588,34 @@ function test_pxset(prefix set pxs)
 	bt_assert(1.0.0.0/8 ~ [ 1.0.0.0/8+ ]);
 	bt_assert(1.0.0.0/9 !~ [ 1.0.0.0/8- ]);
 	bt_assert(1.2.0.0/17 !~ [ 1.0.0.0/8{ 15 , 16 } ]);
+	bt_assert(net10 !~ []);
 
 	bt_assert([ 10.0.0.0/8{ 15 , 17 } ] = [ 10.0.0.0/8{ 15 , 17 } ]);
 }
 
+function test_empty_pxset(prefix set pxs)
+int set s0;
+prefix set s1;
+{
+	s0 = [];
+	s1 = [];
+	bt_assert(pxs != s0);
+	bt_assert(pxs = s1);
+	bt_assert(pxs = []);
+}
+
 function t_prefix_set()
 prefix set pxs;
 {
+	pxs = [];
+	bt_assert(format(pxs) = "[]");
+	bt_assert(pxs = []);
+	bt_assert(1.2.0.0/16 !~ []);
+	bt_assert(1.2.0.0/16 !~ pxs);
+
+	test_empty_pxset([]);
+	test_empty_pxset(pxs);
+
 	pxs = [ 1.2.0.0/16, 1.4.0.0/16+, 44.66.88.64/30{24,28}, 12.34.56.0/24{8,16} ];
 	bt_assert(format(pxs) = "[1.2.0.0/16{0.1.0.0}, 1.4.0.0/16{0.1.255.255}, 12.34.0.0/16{1.255.0.0}, 44.66.88.64/28{0.0.1.240}]");
 
@@ -673,6 +700,12 @@ bt_test_suite(t_prefix6, "Testing prefix IPv6");
 function t_prefix6_set()
 prefix set pxs;
 {
+	pxs = [];
+	bt_assert(format(pxs) = "[]");
+	bt_assert(pxs = []);
+	bt_assert(12::34/128 !~ []);
+	bt_assert(12::34/128 !~ pxs);
+
 	bt_assert(1180::/16 ~ [ 1100::/8{15, 17} ]);
 	bt_assert(12::34 = 12::34);
 	bt_assert(12::34 ~ [ 12::33..12::35 ]);
@@ -790,6 +823,7 @@ int set set12;
 	bt_assert(3 ~ p2);
 	bt_assert(p2 ~ [2, 10..20]);
 	bt_assert(p2 ~ [4, 10..20]);
+	bt_assert(p2 !~ []);
 
 	p2 = prepend(p2, 5);
 	bt_assert(p2 !~ pm1);
@@ -800,6 +834,8 @@ int set set12;
 	bt_assert(p2 ~ [= 5 [2, 4, 6] 3 [1..2] 1 =]);
 	bt_assert(p2 ~ [= 5 set35 3 set12 set12 =]);
 	bt_assert(p2 ~ mkpath(5, 4));
+	bt_assert(p2 ~ [= * [3] * =]);
+	bt_assert(p2 !~ [= * [] * =]);
 
 	bt_assert(p2.len = 5);
 	bt_assert(p2.first = 5);
@@ -808,6 +844,10 @@ int set set12;
 	bt_assert(p2.len = 5);
 	bt_assert(delete(p2, 3) = prepend(prepend(prepend(prepend(+empty+, 1), 2), 4), 5));
 	bt_assert(filter(p2, [1..3]) = prepend(prepend(prepend(+empty+, 1), 2), 3));
+	bt_assert(delete(p2, []) = p2);
+	bt_assert(filter(p2, []) = +empty+);
+	bt_assert(delete(prepend(prepend(+empty+, 0), 1), []) = prepend(prepend(+empty+, 0), 1));
+	bt_assert(filter(prepend(prepend(+empty+, 0), 1), []) = +empty+);
 
 	p2 = prepend( + empty +, 5 );
 	p2 = prepend( p2, 4 );
@@ -827,6 +867,15 @@ int set set12;
 	bt_assert(delete(p2, [4..5]) = prepend(prepend(prepend(prepend(+empty+, 3), 3), 2), 1));
 
 	bt_assert(format([= 1 2+ 3 =]) = "[= 1 2 + 3 =]");
+
+	# iteration over path
+	int x = 0;
+	int y = 0;
+	for int i in p2 do {
+	    x = x + i;
+	    y = y + x;
+	}
+	bt_assert(x = 18 && y = 50);
 }
 
 bt_test_suite(t_path, "Testing paths");
@@ -868,6 +917,7 @@ clist r;
 	bt_assert(l ~ [(2,2..3)]);
 	bt_assert(l ~ [(1,1..2)]);
 	bt_assert(l ~ [(1,1)..(1,2)]);
+	bt_assert(l !~ []);
 
 	l = add(l, (2,5));
 	l = add(l, (5,one));
@@ -905,6 +955,9 @@ clist r;
 	bt_assert(l !~ [(*,(one+6))]);
 	bt_assert(l !~ [(*, (one+one+one))]);
 
+	bt_assert(delete(l, []) = l);
+	bt_assert(filter(l, []) = -empty-);
+
 	l = delete(l, [(*,(one+onef(3)))]);
 	l = delete(l, [(*,(4+one))]);
 	bt_assert(l = add(-empty-, (3,1)));
@@ -949,6 +1002,12 @@ clist r;
 	bt_assert(format(r) = "(clist (2,1) (1,3) (2,2) (3,1) (2,3))");
 	bt_assert(r.min = (1,3));
 	bt_assert(r.max = (3,1));
+
+	# iteration over clist
+	int x = 0;
+	for pair c in r do
+	    x = x + c.asn * c.asn * c.data;
+	bt_assert(x = 36);
 }
 
 bt_test_suite(t_clist, "Testing lists of communities");
@@ -1022,11 +1081,15 @@ eclist r;
 	bt_assert((ro, 10.20.30.40, 100) !~ el);
 	bt_assert(el !~ [(rt, 10, 35..40)]);
 	bt_assert(el !~ [(ro, 10, *)]);
+	bt_assert(el !~ []);
 
 	el = add(el, (rt, 10, 40));
 	el2 = filter(el, [(rt, 10, 20..40)] );
 	el2 = add(el2, (rt, 10, 50));
 
+	bt_assert(delete(el, []) = el);
+	bt_assert(filter(el, []) = --empty--);
+
 	#  eclist A (1,30,40)
 	bt_assert(el = add(add(add(--empty--, (rt, 10, 1)), (rt, 10, 30)), (rt, 10, 40)));
 	bt_assert(format(el) = "(eclist (rt, 10, 1) (rt, 10, 30) (rt, 10, 40))");
@@ -1060,6 +1123,13 @@ eclist r;
 	bt_assert(format(r) = "(eclist (rt, 2, 1) (rt, 1, 3) (rt, 2, 2) (rt, 3, 1) (rt, 2, 3))");
 	bt_assert(r.min = (rt, 1, 3));
 	bt_assert(r.max = (rt, 3, 1));
+
+	# iteration over eclist
+	int x = 0;
+	for ec c in r do
+	  if c > (rt, 2, 0) && c < (rt, 3, 0) then
+	    x = x + 1;
+	bt_assert(x = 3);
 }
 
 bt_test_suite(t_eclist, "Testing lists of extended communities");
@@ -1144,6 +1214,9 @@ lclist r;
 	ll2 = add(ll2, (30, 30, 30));
 	ll2 = add(ll2, (40, 40, 40));
 
+	bt_assert(delete(ll, []) = ll);
+	bt_assert(filter(ll, []) = ---empty---);
+
 	#  lclist A (10, 20, 30)
 	bt_assert(format(ll) = "(lclist (10, 10, 10) (20, 20, 20) (30, 30, 30))");
 
@@ -1175,6 +1248,19 @@ lclist r;
 	bt_assert(format(r) = "(lclist (2, 3, 3) (1, 2, 3) (2, 3, 1) (3, 1, 2) (2, 1, 3))");
 	bt_assert(r.min = (1, 2, 3));
 	bt_assert(r.max = (3, 1, 2));
+
+	# iteration over lclist
+	int x = 0;
+	int y = 0;
+	lc mx = (0, 0, 0);
+	for lc c in r do {
+	    int asn2 = c.asn * c.asn;
+	    x = x + asn2 * c.data1;
+	    y = y + asn2 * c.data2;
+	    if c > mx then mx = c;
+	}
+	bt_assert(x = 39 && y = 49);
+	bt_assert(mx = r.max);
 }
 
 bt_test_suite(t_lclist, "Testing lists of large communities");
@@ -1203,6 +1289,7 @@ lc set lls;
 	bt_assert(ll !~ [(5,10,15), (10,21,30)]);
 	bt_assert(ll !~ [(10,21..25,*)]);
 	bt_assert(ll !~ [(11, *, *)]);
+	bt_assert(ll !~ []);
 
 	lls = [(10, 10, 10), (20, 20, 15..25), (30, 30, *), (40, 35..45, *), (50, *, *), (55..65, *, *)];
 	bt_assert(format(lls) = "[(10, 10, 10), (20, 20, 15)..(20, 20, 25), (30, 30, 0)..(30, 30, 4294967295), (40, 35, 0)..(40, 45, 4294967295), (50, 0, 0)..(50, 4294967295, 4294967295), (55, 0, 0)..(65, 4294967295, 4294967295)]");
@@ -1259,6 +1346,10 @@ bt_test_suite(t_rd, "Testing route distinguishers");
 function t_rd_set()
 rd set rds;
 {
+	rds = [];
+	bt_assert(rds = []);
+	bt_assert(10:20 !~ rds);
+
 	rds = [10:20, 100000:100..100000:200];
 	bt_assert(format(rds)  = "[10:20, 100000:100..100000:200]");
 
@@ -1269,6 +1360,7 @@ rd set rds;
 	bt_assert(100000:128 ~ rds);
 	bt_assert(100000:200 ~ rds);
 	bt_assert(100010:150 !~ rds);
+	bt_assert(100010:150 !~ []);
 }
 
 bt_test_suite(t_rd_set, "Testing sets of route distinguishers");
@@ -1335,7 +1427,85 @@ function fifteen()
 	return 15;
 }
 
+function local_vars(int j)
+{
+	int k = 10;
+	bt_assert(j = 5 && k = 10);
+	{
+		int j = 15;
+		k = 20;
+		bt_assert(j = 15 && k = 20);
+	}
+	bt_assert(j = 5 && k = 20);
+
+	if j < 10 then
+	{
+		int j = 25;
+		string k = "hello";
+		bt_assert(j = 25 && k = "hello");
+	}
+	bt_assert(j = 5 && k = 20);
+
+	int m = 100;
+	{
+		j = 35;
+		int k = 40;
+		bt_assert(j = 35 && k = 40 && m = 100);
+	}
+	bt_assert(j = 35 && k = 20 && m = 100);
+}
+
+function factorial(int x)
+{
+	if x = 0 then return 0;
+	if x = 1 then return 1;
+	else return x * factorial(x - 1);
+}
+
+function fibonacci(int x)
+{
+	if x = 0 then return 0;
+	if x = 1 then return 1;
+	else return fibonacci(x - 1) + fibonacci(x - 2);
+}
+
+function hanoi_init(int a; int b)
+{
+	if b = 0
+	then return +empty+;
+	else return prepend(hanoi_init(a + 1, b - 1), a);
+}
+
+function hanoi_solve(int n; bgppath h_src; bgppath h_dst; bgppath h_aux; bool x; bool y)
+{
+	# x -> return src or dst
+	# y -> print state
+
+	if n = 0 then { if x then return h_src; else return h_dst; }
+
+	bgppath tmp1 = hanoi_solve(n - 1, h_src, h_aux, h_dst, true, y);
+	bgppath tmp2 = hanoi_solve(n - 1, h_src, h_aux, h_dst, false, false);
+	h_src = tmp1;
+	h_aux = tmp2;
+
+	int v = h_src.first;
+	# bt_assert(h_dst = +empty+ || v < h_dst.first);
+	h_src = delete(h_src, v);
+	h_dst = prepend(h_dst, v);
+
+	if y then
+		print "move: ", v, " src: ", h_src, " dst:", h_dst, " aux:", h_aux;
+
+	tmp1 = hanoi_solve(n - 1, h_aux, h_dst, h_src, true, y);
+	tmp2 = hanoi_solve(n - 1, h_aux, h_dst, h_src, false, false);
+	h_aux = tmp1;
+	h_dst = tmp2;
+
+	if x then return h_src; else return h_dst;
+}
+
 function t_call_function()
+bgppath h_src;
 {
 	bt_assert(fifteen() = 15);
 
@@ -1347,6 +1517,17 @@ function t_call_function()
 	bt_assert(callme(4, 4) = 16);
 	bt_assert(callme(7, 2) = 14);
 	bt_assert(callmeagain(1, 2, 3) = 6);
+	local_vars(5);
+
+	bt_assert(factorial(5) = 120);
+	bt_assert(factorial(10) = 3628800);
+
+	bt_assert(fibonacci(10) = 55);
+	bt_assert(fibonacci(20) = 6765);
+
+	h_src = hanoi_init(1, 6);
+	bt_assert(format(h_src) = "(path 1 2 3 4 5 6)");
+	bt_assert(hanoi_solve(6, h_src, +empty+, +empty+, false, false) = h_src);
 }
 
 bt_test_suite(t_call_function, "Testing calling functions");
@@ -1592,13 +1773,16 @@ filter vpn_filter
 	bt_assert(net.type != NET_IP6);
 	bt_assert(net.rd = 0:1:2);
 
+	bool b = false;
 	case (net.type) {
 	  NET_IP4: print "IPV4";
 	  NET_IP6: print "IPV6";
+	  else: b = true;
 	}
+	bt_assert(b);
 
 	bt_check_assign(from, 10.20.30.40);
-	bt_check_assign(gw, 55.55.55.44);
+	# bt_check_assign(gw, 55.55.55.44);
 
 	bgp_community.add((3,5));
 	bgp_ext_community.add((ro, 135, 999));
diff --git a/lib/Makefile b/lib/Makefile
index 15f757d9..f4ade9a6 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -1,4 +1,4 @@
-src := a-path.c a-set.c bitmap.c bitops.c blake2s.c blake2b.c checksum.c event.c flowspec.c idm.c ip.c lists.c mac.c md5.c mempool.c net.c patmatch.c printf.c resource.c sha1.c sha256.c sha512.c slab.c slists.c strtoul.c tbf.c timer.c xmalloc.c
+src := a-path.c a-set.c bitmap.c bitops.c blake2s.c blake2b.c checksum.c event.c flowspec.c idm.c ip.c lists.c mac.c md5.c mempool.c net.c patmatch.c printf.c rcu.c resource.c sha1.c sha256.c sha512.c slab.c slists.c strtoul.c tbf.c timer.c xmalloc.c
 obj := $(src-o-files)
 $(all-daemon)
 
diff --git a/lib/a-path.c b/lib/a-path.c
index 0eca8475..a7a22e40 100644
--- a/lib/a-path.c
+++ b/lib/a-path.c
@@ -602,8 +602,10 @@ as_path_match_set(const struct adata *path, const struct f_tree *set)
 }
 
 const struct adata *
-as_path_filter(struct linpool *pool, const struct adata *path, const struct f_tree *set, u32 key, int pos)
+as_path_filter(struct linpool *pool, const struct adata *path, const struct f_val *set, int pos)
 {
+  ASSERT((set->type == T_SET) || (set->type == T_INT));
+
   if (!path)
     return NULL;
 
@@ -629,13 +631,13 @@ as_path_filter(struct linpool *pool, const struct adata *path, const struct f_tr
 	  u32 as = get_as(p);
 	  int match;
 
-	  if (set)
+	  if (set->type == T_SET)
 	    {
 	      struct f_val v = { .type = T_INT, .val.i = as};
-	      match = !!find_tree(set, &v);
+	      match = !!find_tree(set->val.t, &v);
 	    }
-	  else
-	    match = (as == key);
+	  else /* T_INT */
+	    match = (as == set->val.i);
 
 	  if (match == pos)
 	    {
@@ -667,6 +669,35 @@ as_path_filter(struct linpool *pool, const struct adata *path, const struct f_tr
   return res;
 }
 
+int
+as_path_walk(const struct adata *path, uint *pos, uint *val)
+{
+  if (!path)
+    return 0;
+
+  const u8 *p = path->data;
+  const u8 *q = p + path->length;
+  uint n, x = *pos;
+
+  while (p < q)
+  {
+    n = p[1];
+    p += 2;
+
+    if (x < n)
+    {
+      *val = get_as(p + x * BS);
+      *pos += 1;
+      return 1;
+    }
+
+    p += n * BS;
+    x -= n;
+  }
+
+  return 0;
+}
+
 
 struct pm_pos
 {
diff --git a/lib/a-path_test.c b/lib/a-path_test.c
index 38f77642..c6f8ce8b 100644
--- a/lib/a-path_test.c
+++ b/lib/a-path_test.c
@@ -12,6 +12,7 @@
 #include "nest/rt.h"
 #include "lib/attrs.h"
 #include "lib/resource.h"
+#include "filter/data.h"
 
 #define TESTS_NUM 30
 #define AS_PATH_LENGTH 1000
@@ -127,8 +128,9 @@ t_path_include(void)
     int counts_of_contains = count_asn_in_array(as_nums, as_nums[i]);
     bt_assert_msg(as_path_contains(as_path, as_nums[i], counts_of_contains), "AS Path should contains %d-times number %d", counts_of_contains, as_nums[i]);
 
-    bt_assert(as_path_filter(tmp_linpool, as_path, NULL, as_nums[i], 0) != NULL);
-    bt_assert(as_path_filter(tmp_linpool, as_path, NULL, as_nums[i], 1) != NULL);
+    struct f_val v = { .type = T_INT, .val.i = as_nums[i] };
+    bt_assert(as_path_filter(tmp_linpool, as_path, &v, 0) != NULL);
+    bt_assert(as_path_filter(tmp_linpool, as_path, &v, 1) != NULL);
   }
 
   for (i = 0; i < 10000; i++)
diff --git a/lib/a-set.c b/lib/a-set.c
index 8ede9b83..dcb86058 100644
--- a/lib/a-set.c
+++ b/lib/a-set.c
@@ -693,3 +693,51 @@ lc_set_max(const struct adata *list, lcomm *val)
   *val = (lcomm) { res[0], res[1], res[2] };
   return 1;
 }
+
+int
+int_set_walk(const struct adata *list, uint *pos, uint *val)
+{
+  if (!list)
+    return 0;
+
+  if (*pos >= (uint) int_set_get_size(list))
+    return 0;
+
+  u32 *res = int_set_get_data(list) + *pos;
+  *val = *res;
+  *pos += 1;
+
+  return 1;
+}
+
+int
+ec_set_walk(const struct adata *list, uint *pos, u64 *val)
+{
+  if (!list)
+    return 0;
+
+  if (*pos >= (uint) int_set_get_size(list))
+    return 0;
+
+  u32 *res = int_set_get_data(list) + *pos;
+  *val = ec_generic(res[0], res[1]);
+  *pos += 2;
+
+  return 1;
+}
+
+int
+lc_set_walk(const struct adata *list, uint *pos, lcomm *val)
+{
+  if (!list)
+    return 0;
+
+  if (*pos >= (uint) int_set_get_size(list))
+    return 0;
+
+  u32 *res = int_set_get_data(list) + *pos;
+  *val = (lcomm) { res[0], res[1], res[2] };
+  *pos += 3;
+
+  return 1;
+}
diff --git a/lib/a-set_test.c b/lib/a-set_test.c
index 3280031f..693b8f08 100644
--- a/lib/a-set_test.c
+++ b/lib/a-set_test.c
@@ -221,6 +221,7 @@ t_set_ec_delete(void)
   return 1;
 }
 
+
 int
 main(int argc, char *argv[])
 {
diff --git a/lib/attrs.h b/lib/attrs.h
index a75abcd3..af2f1036 100644
--- a/lib/attrs.h
+++ b/lib/attrs.h
@@ -60,6 +60,7 @@ static inline int adata_same(const struct adata *a, const struct adata *b)
  * to 16bit slot (like in 16bit AS_PATH). See RFC 4893 for details
  */
 
+struct f_val;
 struct f_tree;
 
 int as_path_valid(byte *data, uint len, int bs, int sets, int confed, char *err, uint elen);
@@ -81,7 +82,8 @@ int as_path_get_last(const struct adata *path, u32 *last_as);
 u32 as_path_get_last_nonaggregated(const struct adata *path);
 int as_path_contains(const struct adata *path, u32 as, int min);
 int as_path_match_set(const struct adata *path, const struct f_tree *set);
-const struct adata *as_path_filter(struct linpool *pool, const struct adata *path, const struct f_tree *set, u32 key, int pos);
+const struct adata *as_path_filter(struct linpool *pool, const struct adata *path, const struct f_val *set, int pos);
+int as_path_walk(const struct adata *path, uint *pos, uint *val);
 
 static inline struct adata *as_path_prepend(struct linpool *pool, const struct adata *path, u32 as)
 { return as_path_prepend2(pool, path, AS_PATH_SEQUENCE, as); }
@@ -256,6 +258,9 @@ int lc_set_min(const struct adata *list, lcomm *val);
 int int_set_max(const struct adata *list, u32 *val);
 int ec_set_max(const struct adata *list, u64 *val);
 int lc_set_max(const struct adata *list, lcomm *val);
+int int_set_walk(const struct adata *list, uint *pos, u32 *val);
+int ec_set_walk(const struct adata *list, uint *pos, u64 *val);
+int lc_set_walk(const struct adata *list, uint *pos, lcomm *val);
 
 void ec_set_sort_x(struct adata *set); /* Sort in place */
 
diff --git a/lib/birdlib.h b/lib/birdlib.h
index 9b6e4a16..d55b1a44 100644
--- a/lib/birdlib.h
+++ b/lib/birdlib.h
@@ -15,7 +15,7 @@
 /* Ugly structure offset handling macros */
 
 #define OFFSETOF(s, i) ((size_t) &((s *)0)->i)
-#define SKIP_BACK(s, i, p) ((s *)((char *)p - OFFSETOF(s, i)))
+#define SKIP_BACK(s, i, p) ({ s *_ptr = ((s *)((char *)p - OFFSETOF(s, i))); ASSERT_DIE(&_ptr->i == p); _ptr; })
 #define BIRD_ALIGN(s, a) (((s)+a-1)&~(a-1))
 #define CPU_STRUCT_ALIGN  (MAX_(_Alignof(void*), _Alignof(u64)))
 #define BIRD_CPU_ALIGN(s) BIRD_ALIGN((s), CPU_STRUCT_ALIGN)
@@ -86,6 +86,7 @@ static inline int u64_cmp(u64 i1, u64 i2)
 /* Macros for gcc attributes */
 
 #define NORET __attribute__((noreturn))
+#define USE_RESULT __atribute__((warn_unused_result))
 #define UNUSED __attribute__((unused))
 #define PACKED __attribute__((packed))
 #define NONNULL(...) __attribute__((nonnull((__VA_ARGS__))))
@@ -93,10 +94,6 @@ static inline int u64_cmp(u64 i1, u64 i2)
 #define STATIC_ASSERT(EXP) _Static_assert(EXP, #EXP)
 #define STATIC_ASSERT_MSG(EXP,MSG) _Static_assert(EXP, MSG)
 
-#ifndef HAVE_THREAD_LOCAL
-#define _Thread_local
-#endif
-
 /* Microsecond time */
 
 typedef s64 btime;
@@ -178,8 +175,13 @@ void debug(const char *msg, ...);	/* Printf to debug output */
 
 #if defined(LOCAL_DEBUG) || defined(GLOBAL_DEBUG)
 #define DBG(x, y...) debug(x, ##y)
+#define DBGL(x, y...) debug(x "\n", ##y)
+#elif defined(DEBUG_TO_LOG)
+#define DBG(...) do { } while (0)
+#define DBGL(...) log(L_DEBUG __VA_ARGS__)
 #else
-#define DBG(x, y...) do { } while(0)
+#define DBG(...) do { } while(0)
+#define DBGL(...) do { } while (0)
 #endif
 
 #define ASSERT_DIE(x) do { if (!(x)) bug("Assertion '%s' failed at %s:%d", #x, __FILE__, __LINE__); } while(0)
diff --git a/lib/event.c b/lib/event.c
index 33dc00b0..07d7dc53 100644
--- a/lib/event.c
+++ b/lib/event.c
@@ -19,20 +19,95 @@
  * events in them and explicitly ask to run them.
  */
 
+#undef LOCAL_DEBUG
+
 #include "nest/bird.h"
 #include "lib/event.h"
+#include "lib/io-loop.h"
 
 event_list global_event_list;
 event_list global_work_list;
 
-inline void
-ev_postpone(event *e)
+STATIC_ASSERT(OFFSETOF(event_list, _sentinel.next) >= OFFSETOF(event_list, _end[0]));
+
+void
+ev_init_list(event_list *el, struct birdloop *loop, const char *name)
+{
+  el->name = name;
+  el->loop = loop;
+
+  atomic_store_explicit(&el->receiver, &el->_sentinel, memory_order_relaxed);
+  atomic_store_explicit(&el->_executor, &el->_sentinel, memory_order_relaxed);
+  atomic_store_explicit(&el->_sentinel.next, NULL, memory_order_relaxed);
+}
+
+/*
+ * The event list should work as a message passing point. Sending a message
+ * must be a fairly fast process with no locks and low waiting times. OTOH,
+ * processing messages always involves running the assigned code and the
+ * receiver is always a single one thread with no concurrency at all. There is
+ * also a postponing requirement to synchronously remove an event from a queue,
+ * yet we allow this only when the caller has its receiver event loop locked.
+ * It still means that the event may get postponed from other event in the same
+ * list, therefore we have to be careful.
+ */
+
+static inline int
+ev_remove_from(event *e, event * _Atomic * head)
 {
-  if (ev_active(e))
+  /* The head pointer stores where cur is pointed to from */
+  event * _Atomic *prev = head;
+
+  /* The current event in queue to check */
+  event *cur = atomic_load_explicit(prev, memory_order_acquire);
+
+  /* Pre-loaded next pointer; if NULL, this is sentinel */
+  event *next = atomic_load_explicit(&cur->next, memory_order_acquire);
+
+  while (next)
+  {
+    if (e == cur)
     {
-      rem_node(&e->n);
-      e->n.next = NULL;
+      /* Check whether we have collided with somebody else
+       * adding an item to the queue. */
+      if (!atomic_compare_exchange_strong_explicit(
+	    prev, &cur, next,
+	    memory_order_acq_rel, memory_order_acquire))
+      {
+	/* This may happen only on list head */
+	ASSERT_DIE(prev == head);
+
+	/* Restart. The collision should never happen again. */
+	return ev_remove_from(e, head);
+      }
+
+      /* Successfully removed from the list; inactivate this event. */
+      atomic_store_explicit(&cur->next, NULL, memory_order_release);
+      return 1;
     }
+
+    /* Go to the next event. */
+    prev = &cur->next;
+    cur = next;
+    next = atomic_load_explicit(&cur->next, memory_order_acquire);
+  }
+
+  return 0;
+}
+
+inline void
+ev_postpone(event *e)
+{
+  /* Find the list to remove the event from */
+  event_list *sl = ev_get_list(e);
+  if (!sl)
+    return;
+
+  /* Postponing allowed only from the target loop */
+  ASSERT_DIE(birdloop_inside(sl->loop));
+
+  /* Remove from one of these lists. */
+  ASSERT(ev_remove_from(e, &sl->_executor) || ev_remove_from(e, &sl->receiver));
 }
 
 static void
@@ -43,7 +118,7 @@ ev_dump(resource *r)
   debug("(code %p, data %p, %s)\n",
 	e->hook,
 	e->data,
-	e->n.next ? "scheduled" : "inactive");
+	atomic_load_explicit(&e->next, memory_order_relaxed) ? "scheduled" : "inactive");
 }
 
 static struct resclass ev_class = {
@@ -95,40 +170,21 @@ ev_run(event *e)
  * list @l which can be run by calling ev_run_list().
  */
 inline void
-ev_enqueue(event_list *l, event *e)
-{
-  ev_postpone(e);
-  add_tail(l, &e->n);
-}
-
-/**
- * ev_schedule - schedule an event
- * @e: an event
- *
- * This function schedules an event by enqueueing it to a system-wide
- * event list which is run by the platform dependent code whenever
- * appropriate.
- */
-void
-ev_schedule(event *e)
-{
-  ev_enqueue(&global_event_list, e);
-}
-
-/**
- * ev_schedule_work - schedule a work-event.
- * @e: an event
- *
- * This function schedules an event by enqueueing it to a system-wide work-event
- * list which is run by the platform dependent code whenever appropriate. This
- * is designated for work-events instead of regular events. They are executed
- * less often in order to not clog I/O loop.
- */
-void
-ev_schedule_work(event *e)
+ev_send(event_list *l, event *e)
 {
-  if (!ev_active(e))
-    add_tail(&global_work_list, &e->n);
+  event_list *sl = ev_get_list(e);
+  if (sl == l)
+    return;
+  if (sl)
+    bug("Queuing an already queued event to another queue is not supported.");
+
+  event *next = atomic_load_explicit(&l->receiver, memory_order_acquire);
+  do atomic_store_explicit(&e->next, next, memory_order_relaxed);
+  while (!atomic_compare_exchange_strong_explicit(
+	&l->receiver, &next, e,
+	memory_order_acq_rel, memory_order_acquire));
+
+  birdloop_ping(l->loop);
 }
 
 void io_log_event(void *hook, void *data);
@@ -140,62 +196,56 @@ void io_log_event(void *hook, void *data);
  * This function calls ev_run() for all events enqueued in the list @l.
  */
 int
-ev_run_list(event_list *l)
+ev_run_list_limited(event_list *l, uint limit)
 {
-  node *n;
-  list tmp_list;
+  event * _Atomic *ep = &l->_executor;
 
-  init_list(&tmp_list);
-  add_tail_list(&tmp_list, l);
-  init_list(l);
-  WALK_LIST_FIRST(n, tmp_list)
-    {
-      event *e = SKIP_BACK(event, n, n);
-
-      /* This is ugly hack, we want to log just events executed from the main I/O loop */
-      if ((l == &global_event_list) || (l == &global_work_list))
-	io_log_event(e->hook, e->data);
+  /* No pending events, refill the queue. */
+  if (atomic_load_explicit(ep, memory_order_relaxed) == &l->_sentinel)
+  {
+    /* Move the current event list aside and create a new one. */
+    event *received = atomic_exchange_explicit(
+	&l->receiver, &l->_sentinel, memory_order_acq_rel);
 
-      ev_run(e);
-      tmp_flush();
-    }
+    /* No event to run. */
+    if (received == &l->_sentinel)
+      return 0;
 
-  return !EMPTY_LIST(*l);
-}
+    /* Setup the executor queue */
+    event *head = &l->_sentinel;
 
-int
-ev_run_list_limited(event_list *l, uint limit)
-{
-  node *n;
-  list tmp_list;
+    /* Flip the order of the events by relinking them one by one (push-pop) */
+    while (received != &l->_sentinel)
+    {
+      event *cur = received;
+      received = atomic_exchange_explicit(&cur->next, head, memory_order_relaxed);
+      head = cur;
+    }
 
-  init_list(&tmp_list);
-  add_tail_list(&tmp_list, l);
-  init_list(l);
+    /* Store the executor queue to its designated place */
+    atomic_store_explicit(ep, head, memory_order_relaxed);
+  }
 
-  WALK_LIST_FIRST(n, tmp_list)
+  /* Run the events in order. */
+  event *e;
+  while ((e = atomic_load_explicit(ep, memory_order_relaxed)) != &l->_sentinel)
     {
-      event *e = SKIP_BACK(event, n, n);
-
-      if (!limit)
-	break;
+      /* Check limit */
+      if (!--limit)
+	return 1;
 
       /* This is ugly hack, we want to log just events executed from the main I/O loop */
       if ((l == &global_event_list) || (l == &global_work_list))
 	io_log_event(e->hook, e->data);
 
-      ev_run(e);
+      /* Inactivate the event */
+      atomic_store_explicit(ep, atomic_load_explicit(&e->next, memory_order_relaxed), memory_order_relaxed);
+      atomic_store_explicit(&e->next, NULL, memory_order_relaxed);
+
+      /* Run the event */
+      e->hook(e->data);
       tmp_flush();
-      limit--;
     }
 
-  if (!EMPTY_LIST(tmp_list))
-  {
-    /* Attach new items after the unprocessed old items */
-    add_tail_list(&tmp_list, l);
-    init_list(l);
-    add_tail_list(l, &tmp_list);
-  }
-
-  return !EMPTY_LIST(*l);
+  return atomic_load_explicit(&l->receiver, memory_order_relaxed) != &l->_sentinel;
 }
diff --git a/lib/event.h b/lib/event.h
index 5f3b78d8..9773c3a9 100644
--- a/lib/event.h
+++ b/lib/event.h
@@ -10,33 +10,69 @@
 #define _BIRD_EVENT_H_
 
 #include "lib/resource.h"
+#include "lib/locking.h"
+
+#include <stdatomic.h>
+
+struct birdloop;
 
 typedef struct event {
   resource r;
   void (*hook)(void *);
   void *data;
-  node n;				/* Internal link */
+  struct event * _Atomic next;
 } event;
 
-typedef list event_list;
+typedef union event_list {
+  struct {
+    event * _Atomic receiver;	/* Event receive list */
+    event * _Atomic _executor;	/* Event execute list */
+    const char *name;
+    struct birdloop *loop;	/* The executor loop */
+    char _end[0];
+  };
+  event _sentinel;	/* Sentinel node to actively detect list end */
+} event_list;
 
 extern event_list global_event_list;
 extern event_list global_work_list;
 
 event *ev_new(pool *);
 void ev_run(event *);
-#define ev_init_list(el) init_list(el)
+void ev_init_list(event_list *, struct birdloop *loop, const char *name);
 void ev_enqueue(event_list *, event *);
-void ev_schedule(event *);
-void ev_schedule_work(event *);
+#define ev_send ev_enqueue
+#define ev_send_loop(l, e) ev_send(birdloop_event_list((l)), (e))
+
+#define ev_schedule(e) ({ ASSERT_THE_BIRD_LOCKED; if (!ev_active((e))) ev_send(&global_event_list, (e)); })
+#define ev_schedule_work(e) ({ ASSERT_THE_BIRD_LOCKED; if (!ev_active((e))) ev_send(&global_work_list, (e)); })
+
 void ev_postpone(event *);
-int ev_run_list(event_list *);
 int ev_run_list_limited(event_list *, uint);
+#define ev_run_list(l)	ev_run_list_limited((l), ~0)
+
+#define LEGACY_EVENT_LIST(l)  (((l) == &global_event_list) || ((l) == &global_work_list))
 
 static inline int
 ev_active(event *e)
 {
-  return e->n.next != NULL;
+  return atomic_load_explicit(&e->next, memory_order_relaxed) != NULL;
+}
+
+static inline event_list *
+ev_get_list(event *e)
+{
+  /* We are looking for the sentinel node at the list end.
+   * After this, we have s->next == NULL */
+  event *s = e;
+  for (event *sn; sn = atomic_load_explicit(&s->next, memory_order_acquire); s = sn)
+    ;
+
+  /* No sentinel, no list. */
+  if (s == e)
+    return NULL;
+  else
+    return SKIP_BACK(event_list, _sentinel, s);
 }
 
 static inline event*
diff --git a/lib/event_test.c b/lib/event_test.c
index 3070327d..612deb25 100644
--- a/lib/event_test.c
+++ b/lib/event_test.c
@@ -54,7 +54,6 @@ t_ev_run_list(void)
   int i;
 
   olock_init();
-  timer_init();
   rt_init();
   io_init();
   if_init();
diff --git a/lib/io-loop.h b/lib/io-loop.h
new file mode 100644
index 00000000..2450a609
--- /dev/null
+++ b/lib/io-loop.h
@@ -0,0 +1,58 @@
+/*
+ *	BIRD -- I/O and event loop
+ *
+ *	Can be freely distributed and used under the terms of the GNU GPL.
+ */
+
+#ifndef _BIRD_IO_LOOP_H_
+#define _BIRD_IO_LOOP_H_
+
+#include "nest/bird.h"
+#include "lib/lists.h"
+#include "lib/locking.h"
+#include "lib/resource.h"
+#include "lib/event.h"
+#include "lib/socket.h"
+
+extern struct birdloop main_birdloop;
+
+void sk_start(sock *s);
+void sk_stop(sock *s);
+void sk_reloop(sock *s, struct birdloop *loop);
+
+/* Start a new birdloop owned by given pool and domain */
+struct birdloop *birdloop_new(pool *p, uint order, const char *name);
+
+/* Stop the loop. At the end, the @stopped callback is called unlocked in tail
+ * position to finish cleanup. Run birdloop_free() from that callback to free
+ * the loop itself. */
+void birdloop_stop(struct birdloop *loop, void (*stopped)(void *data), void *data);
+void birdloop_stop_self(struct birdloop *loop, void (*stopped)(void *data), void *data);
+void birdloop_free(struct birdloop *loop);
+
+/* Get birdloop's event list */
+event_list *birdloop_event_list(struct birdloop *loop);
+
+/* Get birdloop's time heap */
+struct timeloop *birdloop_time_loop(struct birdloop *loop);
+
+/* Enter and exit the birdloop */
+void birdloop_enter(struct birdloop *loop);
+void birdloop_leave(struct birdloop *loop);
+
+_Bool birdloop_inside(struct birdloop *loop);
+
+void birdloop_mask_wakeups(struct birdloop *loop);
+void birdloop_unmask_wakeups(struct birdloop *loop);
+
+void birdloop_link(struct birdloop *loop);
+void birdloop_unlink(struct birdloop *loop);
+
+void birdloop_ping(struct birdloop *loop);
+
+void birdloop_init(void);
+
+/* Yield for a little while. Use only in special cases. */
+void birdloop_yield(void);
+
+#endif /* _BIRD_IO_LOOP_H_ */
diff --git a/lib/lists.c b/lib/lists.c
index 200576cf..8f95c7c2 100644
--- a/lib/lists.c
+++ b/lib/lists.c
@@ -26,7 +26,7 @@
 
 #define _BIRD_LISTS_C_
 
-#include "nest/bird.h"
+#include "lib/birdlib.h"
 #include "lib/lists.h"
 
 LIST_INLINE int
@@ -35,11 +35,12 @@ check_list(list *l, node *n)
   if (!l)
   {
     ASSERT_DIE(n);
-    ASSERT_DIE(n->prev);
 
-    do { n = n->prev; } while (n->prev);
+    node *nn = n;
+    while (nn->prev)
+      nn = nn->prev;
 
-    l = SKIP_BACK(list, head_node, n);
+    l = SKIP_BACK(list, head_node, nn);
   }
 
   int seen = 0;
@@ -60,7 +61,7 @@ check_list(list *l, node *n)
   }
 
   ASSERT_DIE(cur == &(l->tail_node));
-  ASSERT_DIE(!n || (seen == 1));
+  ASSERT_DIE(!n || (seen == 1) || (n == &l->head_node) || (n == &l->tail_node));
 
   return 1;
 }
@@ -120,7 +121,7 @@ add_head(list *l, node *n)
 LIST_INLINE void
 insert_node(node *n, node *after)
 {
-  EXPENSIVE_CHECK(check_list(l, after));
+  EXPENSIVE_CHECK(check_list(NULL, after));
   ASSUME(n->prev == NULL);
   ASSUME(n->next == NULL);
 
@@ -141,7 +142,7 @@ insert_node(node *n, node *after)
 LIST_INLINE void
 rem_node(node *n)
 {
-  EXPENSIVE_CHECK(check_list(NULL, n));
+  EXPENSIVE_CHECK((n == n->prev) && (n == n->next) || check_list(NULL, n));
 
   node *z = n->prev;
   node *x = n->next;
diff --git a/lib/lists.h b/lib/lists.h
index 7e6d5467..86ff59c9 100644
--- a/lib/lists.h
+++ b/lib/lists.h
@@ -69,6 +69,18 @@ typedef union list {			/* In fact two overlayed nodes */
 
 #define EMPTY_LIST(list) (!(list).head->next)
 
+static inline _Bool
+enlisted(node *n)
+{
+  switch ((!!n->next) + (!!n->prev))
+  {
+    case 0: return 0;
+    case 2: return 1;
+    case 1: bug("Garbled event list node");
+  }
+
+  bug("Maths is broken. And you should see a new heaven and a new earth: for the first heaven and the first earth had been passed away.");
+}
 
 #ifndef _BIRD_LISTS_C_
 #define LIST_INLINE static inline
diff --git a/lib/locking.h b/lib/locking.h
new file mode 100644
index 00000000..a9a8aa9b
--- /dev/null
+++ b/lib/locking.h
@@ -0,0 +1,63 @@
+/*
+ *	BIRD Library -- Locking
+ *
+ *	(c) 2020--2021 Maria Matejka <mq@jmq.cz>
+ *
+ *	Can be freely distributed and used under the terms of the GNU GPL.
+ */
+
+#ifndef _BIRD_LOCKING_H_
+#define _BIRD_LOCKING_H_
+
+struct domain_generic;
+
+/* Here define the global lock order; first to last. */
+struct lock_order {
+  struct domain_generic *the_bird;
+  struct domain_generic *proto;
+  struct domain_generic *rtable;
+  struct domain_generic *resource;
+};
+
+extern _Thread_local struct lock_order locking_stack;
+extern _Thread_local struct domain_generic **last_locked;
+
+#define DOMAIN(type) struct domain__##type
+#define DEFINE_DOMAIN(type) DOMAIN(type) { struct domain_generic *type; }
+#define DOMAIN_ORDER(type)  OFFSETOF(struct lock_order, type)
+
+#define DOMAIN_NEW(type, name)  (DOMAIN(type)) { .type = domain_new(name, DOMAIN_ORDER(type)) }
+struct domain_generic *domain_new(const char *name, uint order);
+
+#define DOMAIN_FREE(type, d)	domain_free((d).type)
+void domain_free(struct domain_generic *);
+
+#define DOMAIN_NULL(type)   (DOMAIN(type)) {}
+
+#define LOCK_DOMAIN(type, d)	do_lock(((d).type), &(locking_stack.type))
+#define UNLOCK_DOMAIN(type, d)  do_unlock(((d).type), &(locking_stack.type))
+
+#define DOMAIN_IS_LOCKED(type, d) (((d).type) == (locking_stack.type))
+#define DG_IS_LOCKED(d)	((d) == *(DG_LSP(d)))
+
+/* Internal for locking */
+void do_lock(struct domain_generic *dg, struct domain_generic **lsp);
+void do_unlock(struct domain_generic *dg, struct domain_generic **lsp);
+
+uint dg_order(struct domain_generic *dg);
+
+#define DG_LSP(d)	((struct domain_generic **) (((void *) &locking_stack) + dg_order(d)))
+#define DG_LOCK(d)	do_lock(d, DG_LSP(d))
+#define DG_UNLOCK(d)	do_unlock(d, DG_LSP(d))
+
+/* Use with care. To be removed in near future. */
+DEFINE_DOMAIN(the_bird);
+extern DOMAIN(the_bird) the_bird_domain;
+
+#define the_bird_lock()		LOCK_DOMAIN(the_bird, the_bird_domain)
+#define the_bird_unlock()	UNLOCK_DOMAIN(the_bird, the_bird_domain)
+#define the_bird_locked()	DOMAIN_IS_LOCKED(the_bird, the_bird_domain)
+
+#define ASSERT_THE_BIRD_LOCKED	({ if (!the_bird_locked()) bug("The BIRD lock must be locked here: %s:%d", __FILE__, __LINE__); })
+
+#endif
diff --git a/lib/rcu.c b/lib/rcu.c
new file mode 100644
index 00000000..83fdd022
--- /dev/null
+++ b/lib/rcu.c
@@ -0,0 +1,79 @@
+/*
+ *	BIRD Library -- Read-Copy-Update Basic Operations
+ *
+ *	(c) 2021 Maria Matejka <mq@jmq.cz>
+ *	(c) 2021 CZ.NIC z.s.p.o.
+ *
+ *	Can be freely distributed and used under the terms of the GNU GPL.
+ *	Note: all the relevant patents shall be expired.
+ *
+ *	Using the Supplementary Material for User-Level Implementations of Read-Copy-Update
+ *	by Matthieu Desnoyers, Paul E. McKenney, Alan S. Stern, Michel R. Dagenais and Jonathan Walpole
+ *	obtained from https://www.efficios.com/pub/rcu/urcu-supp-accepted.pdf
+ */
+
+#include "lib/rcu.h"
+#include "lib/io-loop.h"
+#include "lib/locking.h"
+
+_Atomic uint rcu_gp_ctl = RCU_NEST_CNT;
+_Thread_local struct rcu_birdloop *this_rcu_birdloop = NULL;
+
+static list rcu_birdloop_list;
+
+static struct rcu_birdloop main_rcu_birdloop;
+
+DEFINE_DOMAIN(resource);
+static DOMAIN(resource) rcu_domain;
+
+static int
+rcu_gp_ongoing(_Atomic uint *ctl)
+{
+  uint val = atomic_load(ctl);
+  return (val & RCU_NEST_CNT) && ((val ^ rcu_gp_ctl) & RCU_GP_PHASE);
+}
+
+static void
+update_counter_and_wait(void)
+{
+  atomic_fetch_xor(&rcu_gp_ctl, RCU_GP_PHASE);
+  struct rcu_birdloop *rc;
+  WALK_LIST(rc, rcu_birdloop_list)
+    while (rcu_gp_ongoing(&rc->ctl))
+      birdloop_yield();
+}
+
+void
+synchronize_rcu(void)
+{
+  LOCK_DOMAIN(resource, rcu_domain);
+  update_counter_and_wait();
+  update_counter_and_wait();
+  UNLOCK_DOMAIN(resource, rcu_domain);
+}
+
+void
+rcu_birdloop_start(struct rcu_birdloop *rc)
+{
+  LOCK_DOMAIN(resource, rcu_domain);
+  add_tail(&rcu_birdloop_list, &rc->n);
+  this_rcu_birdloop = rc;
+  UNLOCK_DOMAIN(resource, rcu_domain);
+}
+
+void
+rcu_birdloop_stop(struct rcu_birdloop *rc)
+{
+  LOCK_DOMAIN(resource, rcu_domain);
+  this_rcu_birdloop = NULL;
+  rem_node(&rc->n);
+  UNLOCK_DOMAIN(resource, rcu_domain);
+}
+
+void
+rcu_init(void)
+{
+  rcu_domain = DOMAIN_NEW(resource, "Read-Copy-Update");
+  init_list(&rcu_birdloop_list);
+  rcu_birdloop_start(&main_rcu_birdloop);
+}
diff --git a/lib/rcu.h b/lib/rcu.h
new file mode 100644
index 00000000..c537a1ef
--- /dev/null
+++ b/lib/rcu.h
@@ -0,0 +1,55 @@
+/*
+ *	BIRD Library -- Read-Copy-Update Basic Operations
+ *
+ *	(c) 2021 Maria Matejka <mq@jmq.cz>
+ *	(c) 2021 CZ.NIC z.s.p.o.
+ *
+ *	Can be freely distributed and used under the terms of the GNU GPL.
+ *	Note: all the relevant patents shall be expired.
+ */
+
+#ifndef _BIRD_RCU_H_
+#define _BIRD_RCU_H_
+
+#include "lib/birdlib.h"
+#include "lib/lists.h"
+#include <stdatomic.h>
+
+#define RCU_GP_PHASE  0x100000
+#define RCU_NEST_MASK 0x0fffff
+#define RCU_NEST_CNT  0x000001
+
+extern _Atomic uint rcu_gp_ctl;
+
+struct rcu_birdloop {
+  node n;
+  _Atomic uint ctl;
+};
+
+extern _Thread_local struct rcu_birdloop *this_rcu_birdloop;
+
+static inline void rcu_read_lock(void)
+{
+  uint cmp = atomic_load_explicit(&this_rcu_birdloop->ctl, memory_order_acquire);
+
+  if (cmp & RCU_NEST_MASK)
+    atomic_store_explicit(&this_rcu_birdloop->ctl, cmp + RCU_NEST_CNT, memory_order_relaxed);
+  else
+    atomic_store(&this_rcu_birdloop->ctl, atomic_load_explicit(&rcu_gp_ctl, memory_order_acquire));
+}
+
+static inline void rcu_read_unlock(void)
+{
+  atomic_fetch_sub(&this_rcu_birdloop->ctl, RCU_NEST_CNT);
+}
+
+void synchronize_rcu(void);
+
+/* Registering and unregistering a birdloop. To be called from birdloop implementation */
+void rcu_birdloop_start(struct rcu_birdloop *);
+void rcu_birdloop_stop(struct rcu_birdloop *);
+
+/* Run this from resource init */
+void rcu_init(void);
+
+#endif
diff --git a/lib/resource.c b/lib/resource.c
index c31d9889..898fb533 100644
--- a/lib/resource.c
+++ b/lib/resource.c
@@ -14,6 +14,7 @@
 #include "nest/bird.h"
 #include "lib/resource.h"
 #include "lib/string.h"
+#include "lib/rcu.h"
 
 /**
  * DOC: Resource pools
@@ -29,12 +30,6 @@
  * is freed upon shutdown of the module.
  */
 
-struct pool {
-  resource r;
-  list inside;
-  const char *name;
-};
-
 static void pool_dump(resource *);
 static void pool_free(resource *);
 static resource *pool_lookup(resource *, unsigned long);
@@ -285,6 +280,7 @@ void
 resource_init(void)
 {
   resource_sys_init();
+  rcu_init();
 
   root_pool.r.class = &pool_class;
   root_pool.name = "Root";
diff --git a/lib/resource.h b/lib/resource.h
index 4cedbf00..5ad011ec 100644
--- a/lib/resource.h
+++ b/lib/resource.h
@@ -40,7 +40,12 @@ struct resclass {
 
 /* Generic resource manipulation */
 
-typedef struct pool pool;
+typedef struct pool {
+  resource r;
+  list inside;
+  const char *name;
+} pool;
+
 
 void resource_init(void);
 pool *rp_new(pool *, const char *);	/* Create new pool */
@@ -115,6 +120,7 @@ void sl_free(void *);
 void buffer_realloc(void **buf, unsigned *size, unsigned need, unsigned item_size);
 
 /* Allocator of whole pages; for use in slabs and other high-level allocators. */
+#define PAGE_HEAD(x)	((void *) (((uintptr_t) (x)) & ~(page_size-1)))
 extern long page_size;
 void *alloc_page(void);
 void free_page(void *);
diff --git a/lib/route.h b/lib/route.h
index 68596316..2d691215 100644
--- a/lib/route.h
+++ b/lib/route.h
@@ -29,12 +29,10 @@ typedef struct rte {
   u8 generation;			/* If this route import is based on other previously exported route,
 					   this value should be 1 + MAX(generation of the parent routes).
 					   Otherwise the route is independent and this value is zero. */
+  u8 stale_cycle;			/* Auxiliary value for route refresh */
 } rte;
 
 #define REF_FILTERED	2		/* Route is rejected by import filter */
-#define REF_STALE	4		/* Route is stale in a refresh cycle */
-#define REF_DISCARD	8		/* Route is scheduled for discard */
-#define REF_MODIFY	16		/* Route is scheduled for modify */
 #define REF_PENDING	32		/* Route has not propagated completely yet */
 
 /* Route is valid for propagation (may depend on other flags in the future), accepts NULL */
@@ -425,7 +423,7 @@ static inline int ea_is_cached(const ea_list *r) { return r->flags & EALF_CACHED
 static inline struct ea_storage *ea_get_storage(ea_list *r)
 {
   ASSERT_DIE(ea_is_cached(r));
-  return SKIP_BACK(struct ea_storage, l, r);
+  return SKIP_BACK(struct ea_storage, l[0], r);
 }
 
 static inline ea_list *ea_clone(ea_list *r) { ea_get_storage(r)->uc++; return r; }
diff --git a/lib/slab.c b/lib/slab.c
index 38d10626..054daea1 100644
--- a/lib/slab.c
+++ b/lib/slab.c
@@ -197,7 +197,7 @@ static struct resclass sl_class = {
   slab_memsize
 };
 
-#define SL_GET_HEAD(x)	((struct sl_head *) (((uintptr_t) (x)) & ~(page_size-1)))
+#define SL_GET_HEAD(x)	PAGE_HEAD(x)
 
 #define SL_HEAD_CHANGE_STATE(_s, _h, _from, _to) ({ \
     ASSERT_DIE(_h->state == slh_##_from); \
diff --git a/lib/socket.h b/lib/socket.h
index 0b6ac589..5c69482e 100644
--- a/lib/socket.h
+++ b/lib/socket.h
@@ -12,6 +12,7 @@
 #include <errno.h>
 
 #include "lib/resource.h"
+#include "lib/event.h"
 #ifdef HAVE_LIBSSH
 #define LIBSSH_LEGACY_0_4
 #include <libssh/libssh.h>
@@ -79,6 +80,7 @@ typedef struct birdsock {
   const char *password;			/* Password for MD5 authentication */
   const char *err;			/* Error message */
   struct ssh_sock *ssh;			/* Used in SK_SSH */
+  struct event reloop;			/* Reloop event */
 } sock;
 
 sock *sock_new(pool *);			/* Allocate new socket */
@@ -129,6 +131,7 @@ extern int sk_priority_control;		/* Suggested priority for control traffic, shou
 #define SKF_TRUNCATED	0x200	/* Received packet was truncated, set by IO layer */
 #define SKF_HDRINCL	0x400	/* Used internally */
 #define SKF_PKTINFO	0x800	/* Used internally */
+#define SKF_PASSIVE_THREAD  0x1000  /* Child sockets used in thread, do not add to main loop */
 
 /*
  *	Socket types		     SA SP DA DP IF  TTL SendTo	(?=may, -=must not, *=must)
diff --git a/lib/timer.c b/lib/timer.c
index c47e0bbc..ff6975a4 100644
--- a/lib/timer.c
+++ b/lib/timer.c
@@ -36,57 +36,13 @@
 #include "lib/resource.h"
 #include "lib/timer.h"
 
-
-struct timeloop main_timeloop;
-
-
-#ifdef USE_PTHREADS
-
 #include <pthread.h>
 
-/* Data accessed and modified from proto/bfd/io.c */
-pthread_key_t current_time_key;
-
-static inline struct timeloop *
-timeloop_current(void)
-{
-  return pthread_getspecific(current_time_key);
-}
-
-static inline void
-timeloop_init_current(void)
-{
-  pthread_key_create(&current_time_key, NULL);
-  pthread_setspecific(current_time_key, &main_timeloop);
-}
+_Atomic btime last_time;
+_Atomic btime real_time;
 
 void wakeup_kick_current(void);
 
-#else
-
-/* Just use main timelooop */
-static inline struct timeloop * timeloop_current(void) { return &main_timeloop; }
-static inline void timeloop_init_current(void) { }
-
-#endif
-
-btime
-current_time(void)
-{
-  return timeloop_current()->last_time;
-}
-
-btime
-current_real_time(void)
-{
-  struct timeloop *loop = timeloop_current();
-
-  if (!loop->real_time)
-    times_update_real_time(loop);
-
-  return loop->real_time;
-}
-
 
 #define TIMER_LESS(a,b)		((a)->expires < (b)->expires)
 #define TIMER_SWAP(heap,a,b,t)	(t = heap[a], heap[a] = heap[b], heap[b] = t, \
@@ -112,7 +68,7 @@ tm_dump(resource *r)
   if (t->recurrent)
     debug("recur %d, ", t->recurrent);
   if (t->expires)
-    debug("expires in %d ms)\n", (t->expires - current_time()) TO_MS);
+    debug("in loop %p expires in %d ms)\n", t->loop, (t->expires - current_time()) TO_MS);
   else
     debug("inactive)\n");
 }
@@ -135,41 +91,40 @@ tm_new(pool *p)
   return t;
 }
 
-void
-tm_set(timer *t, btime when)
+static void
+tm_set_in_tl(timer *t, btime when, struct timeloop *local_timeloop)
 {
-  struct timeloop *loop = timeloop_current();
-  uint tc = timers_count(loop);
+  uint tc = timers_count(local_timeloop);
 
   if (!t->expires)
   {
     t->index = ++tc;
     t->expires = when;
-    BUFFER_PUSH(loop->timers) = t;
-    HEAP_INSERT(loop->timers.data, tc, timer *, TIMER_LESS, TIMER_SWAP);
+    BUFFER_PUSH(local_timeloop->timers) = t;
+    HEAP_INSERT(local_timeloop->timers.data, tc, timer *, TIMER_LESS, TIMER_SWAP);
   }
   else if (t->expires < when)
   {
     t->expires = when;
-    HEAP_INCREASE(loop->timers.data, tc, timer *, TIMER_LESS, TIMER_SWAP, t->index);
+    HEAP_INCREASE(local_timeloop->timers.data, tc, timer *, TIMER_LESS, TIMER_SWAP, t->index);
   }
   else if (t->expires > when)
   {
     t->expires = when;
-    HEAP_DECREASE(loop->timers.data, tc, timer *, TIMER_LESS, TIMER_SWAP, t->index);
+    HEAP_DECREASE(local_timeloop->timers.data, tc, timer *, TIMER_LESS, TIMER_SWAP, t->index);
   }
 
-#ifdef CONFIG_BFD
-  /* Hack to notify BFD loops */
-  if ((loop != &main_timeloop) && (t->index == 1))
-    wakeup_kick_current();
-#endif
+  t->loop = local_timeloop;
+
+  if (t->index == 1)
+    birdloop_ping(local_timeloop->loop);
 }
 
 void
-tm_start(timer *t, btime after)
+tm_set_in(timer *t, btime when, struct birdloop *loop)
 {
-  tm_set(t, current_time() + MAX(after, 0));
+  ASSERT_DIE(birdloop_inside(loop));
+  tm_set_in_tl(t, when, birdloop_time_loop(loop));
 }
 
 void
@@ -178,20 +133,22 @@ tm_stop(timer *t)
   if (!t->expires)
     return;
 
-  struct timeloop *loop = timeloop_current();
-  uint tc = timers_count(loop);
+  TLOCK_TIMER_ASSERT(t->loop);
 
-  HEAP_DELETE(loop->timers.data, tc, timer *, TIMER_LESS, TIMER_SWAP, t->index);
-  BUFFER_POP(loop->timers);
+  uint tc = timers_count(t->loop);
+
+  HEAP_DELETE(t->loop->timers.data, tc, timer *, TIMER_LESS, TIMER_SWAP, t->index);
+  BUFFER_POP(t->loop->timers);
 
   t->index = -1;
   t->expires = 0;
+  t->loop = NULL;
 }
 
 void
 timers_init(struct timeloop *loop, pool *p)
 {
-  times_init(loop);
+  TLOCK_TIMER_ASSERT(loop);
 
   BUFFER_INIT(loop->timers, p, 4);
   BUFFER_PUSH(loop->timers) = NULL;
@@ -200,13 +157,15 @@ timers_init(struct timeloop *loop, pool *p)
 void io_log_event(void *hook, void *data);
 
 void
-timers_fire(struct timeloop *loop)
+timers_fire(struct timeloop *loop, int io_log)
 {
+  TLOCK_TIMER_ASSERT(loop);
+
   btime base_time;
   timer *t;
 
-  times_update(loop);
-  base_time = loop->last_time;
+  times_update();
+  base_time = current_time();
 
   while (t = timers_first(loop))
   {
@@ -217,19 +176,19 @@ timers_fire(struct timeloop *loop)
     {
       btime when = t->expires + t->recurrent;
 
-      if (when <= loop->last_time)
-	when = loop->last_time + t->recurrent;
+      if (when <= base_time)
+	when = base_time + t->recurrent;
 
       if (t->randomize)
 	when += random() % (t->randomize + 1);
 
-      tm_set(t, when);
+      tm_set_in_tl(t, when, loop);
     }
     else
       tm_stop(t);
 
     /* This is ugly hack, we want to log just timers executed from the main I/O loop */
-    if (loop == &main_timeloop)
+    if (io_log)
       io_log_event(t->hook, t->data);
 
     t->hook(t);
@@ -237,13 +196,6 @@ timers_fire(struct timeloop *loop)
   }
 }
 
-void
-timer_init(void)
-{
-  timers_init(&main_timeloop, &root_pool);
-  timeloop_init_current();
-}
-
 
 /**
  * tm_parse_time - parse a date and time
diff --git a/lib/timer.h b/lib/timer.h
index c5ea430c..555fc96f 100644
--- a/lib/timer.h
+++ b/lib/timer.h
@@ -12,8 +12,14 @@
 
 #include "nest/bird.h"
 #include "lib/buffer.h"
+#include "lib/io-loop.h"
+#include "lib/locking.h"
 #include "lib/resource.h"
 
+#include <stdatomic.h>
+
+extern _Atomic btime last_time;
+extern _Atomic btime real_time;
 
 typedef struct timer
 {
@@ -25,36 +31,42 @@ typedef struct timer
   uint randomize;			/* Amount of randomization */
   uint recurrent;			/* Timer recurrence */
 
+  struct timeloop *loop;		/* Loop where the timer is active */
+
   int index;
 } timer;
 
 struct timeloop
 {
   BUFFER_(timer *) timers;
-  btime last_time;
-  btime real_time;
+  struct domain_generic *domain;
+  struct birdloop *loop;
 };
 
+#define TLOCK_TIMER_ASSERT(loop) ASSERT_DIE((loop)->domain && DG_IS_LOCKED((loop)->domain))
+#define TLOCK_LOCAL_ASSERT(loop) ASSERT_DIE(!(loop)->domain || DG_IS_LOCKED((loop)->domain))
+
 static inline uint timers_count(struct timeloop *loop)
-{ return loop->timers.used - 1; }
+{ TLOCK_TIMER_ASSERT(loop); return loop->timers.used - 1; }
 
 static inline timer *timers_first(struct timeloop *loop)
-{ return (loop->timers.used > 1) ? loop->timers.data[1] : NULL; }
+{ TLOCK_TIMER_ASSERT(loop); return (loop->timers.used > 1) ? loop->timers.data[1] : NULL; }
 
-extern struct timeloop main_timeloop;
-
-btime current_time(void);
-btime current_real_time(void);
+#define current_time()		atomic_load_explicit(&last_time, memory_order_acquire)
+#define current_real_time()	atomic_load_explicit(&real_time, memory_order_acquire)
 
 //#define now (current_time() TO_S)
 //#define now_real (current_real_time() TO_S)
 extern btime boot_time;
 
 timer *tm_new(pool *p);
-void tm_set(timer *t, btime when);
-void tm_start(timer *t, btime after);
+#define tm_set(t, when) tm_set_in((t), (when), &main_birdloop)
+#define tm_start(t, after) tm_start_in((t), (after), &main_birdloop)
 void tm_stop(timer *t);
 
+void tm_set_in(timer *t, btime when, struct birdloop *loop);
+#define tm_start_in(t, after, loop) tm_set_in((t), (current_time() + MAX_((after), 0)), loop)
+
 static inline int
 tm_active(timer *t)
 {
@@ -94,15 +106,11 @@ tm_start_max(timer *t, btime after)
 }
 
 /* In sysdep code */
-void times_init(struct timeloop *loop);
-void times_update(struct timeloop *loop);
-void times_update_real_time(struct timeloop *loop);
+void times_update(void);
 
 /* For I/O loop */
 void timers_init(struct timeloop *loop, pool *p);
-void timers_fire(struct timeloop *loop);
-
-void timer_init(void);
+void timers_fire(struct timeloop *loop, int io_log);
 
 
 struct timeformat {
diff --git a/misc/bird.spec b/misc/bird.spec
index 425a6340..c3fdd7d6 100644
--- a/misc/bird.spec
+++ b/misc/bird.spec
@@ -1,6 +1,6 @@
 Summary: BIRD Internet Routing Daemon
 Name: bird
-Version: 2.0.9
+Version: 2.0.10
 Release: 1
 Copyright: GPL
 Group: Networking/Daemons
diff --git a/nest/Makefile b/nest/Makefile
index 0350c3b6..39617350 100644
--- a/nest/Makefile
+++ b/nest/Makefile
@@ -6,7 +6,11 @@ $(call proto-build,dev_build)
 
 $(proto-build-c): $(lastword $(MAKEFILE_LIST))
 	$(E)echo GEN $@
-	$(Q)echo "#include \"lib/birdlib.h\"\n$(patsubst %,void %(void);\n,$(PROTO_BUILD)) void protos_build_gen(void) { $(patsubst %,  %();\n,$(PROTO_BUILD))}" > $@
+	$(Q)echo "#include \"lib/birdlib.h\"" > $@
+	$(Q)$(patsubst %,echo 'void %(void);' >> $@;,$(PROTO_BUILD))
+	$(Q)echo "void protos_build_gen(void) {" >> $@
+	$(Q)$(patsubst %,echo '  %();'>>$@;,$(PROTO_BUILD))
+	$(Q)echo "}" >> $@
 
 tests_src :=
 tests_targets := $(tests_targets) $(tests-target-files)
diff --git a/nest/config.Y b/nest/config.Y
index edddfc2b..91147a29 100644
--- a/nest/config.Y
+++ b/nest/config.Y
@@ -125,7 +125,7 @@ CF_KEYWORDS(TIMEFORMAT, ISO, SHORT, LONG, ROUTE, PROTOCOL, BASE, LOG, S, MS, US)
 CF_KEYWORDS(GRACEFUL, RESTART, WAIT, MAX, AS)
 CF_KEYWORDS(MIN, IDLE, RX, TX, INTERVAL, MULTIPLIER, PASSIVE)
 CF_KEYWORDS(CHECK, LINK)
-CF_KEYWORDS(SORTED, TRIE, MIN, MAX, SETTLE, TIME)
+CF_KEYWORDS(CORK, SORTED, TRIE, MIN, MAX, SETTLE, TIME, GC, THRESHOLD, PERIOD)
 
 /* For r_args_channel */
 CF_KEYWORDS(IPV4, IPV4_MC, IPV4_MPLS, IPV6, IPV6_MC, IPV6_MPLS, IPV6_SADR, VPN4, VPN4_MC, VPN4_MPLS, VPN6, VPN6_MC, VPN6_MPLS, ROA4, ROA6, FLOW4, FLOW6, MPLS, PRI, SEC)
@@ -165,7 +165,7 @@ rtrid:
 
 idval:
    NUM { $$ = $1; }
- | '(' term ')' { $$ = f_eval_int(f_linearize($2)); }
+ | '(' term ')' { $$ = f_eval_int(f_linearize($2, 1)); }
  | IP4 { $$ = ip4_to_u32($1); }
  | CF_SYM_KNOWN {
      if ($1->class == (SYM_CONSTANT | T_INT) || $1->class == (SYM_CONSTANT | T_QUAD))
@@ -229,6 +229,12 @@ table_opt:
    }
  | MIN SETTLE TIME expr_us { this_table->min_settle_time = $4; }
  | MAX SETTLE TIME expr_us { this_table->max_settle_time = $4; }
+ | GC THRESHOLD expr { this_table->gc_threshold = $3; }
+ | GC PERIOD expr_us { this_table->gc_period = (uint) $3; if ($3 > 3600 S_) cf_error("GC period must be at most 3600 s"); }
+ | CORK THRESHOLD expr expr {
+     if ($3 > $4) cf_error("Cork low threshold must be lower than the high threshold.");
+     this_table->cork_threshold.low = $3;
+     this_table->cork_threshold.high = $4; }
  ;
 
 table_opts:
@@ -384,7 +390,7 @@ debug_default:
    DEBUG PROTOCOLS debug_mask { new_config->proto_default_debug = $3; }
  | DEBUG CHANNELS debug_mask { new_config->channel_default_debug = $3; }
  | DEBUG COMMANDS expr { new_config->cli_debug = $3; }
- | DEBUG PIPE bool { new_config->pipe_debug = $3; }
+ | DEBUG TABLES bool { new_config->table_debug = $3; }
  ;
 
 /* MRTDUMP PROTOCOLS is in systep/unix/config.Y */
@@ -470,6 +476,7 @@ proto: dev_proto '}' ;
 dev_proto_start: proto_start DIRECT {
      this_proto = proto_config_new(&proto_device, $1);
      init_list(&DIRECT_CFG->iface_list);
+     this_proto->late_if_feed = 1;
    }
  ;
 
@@ -875,7 +882,7 @@ CF_CLI(DUMP FILTER ALL,,, [[Dump all filters in linearized form]])
 { filters_dump_all(); cli_msg(0, ""); } ;
 
 CF_CLI(EVAL, term, <expr>, [[Evaluate an expression]])
-{ cmd_eval(f_linearize($2)); } ;
+{ cmd_eval(f_linearize($2, 1)); } ;
 
 CF_CLI_HELP(ECHO, ..., [[Control echoing of log messages]])
 CF_CLI(ECHO, echo_mask echo_size, (all | off | { debug|trace|info|remote|warning|error|auth [, ...] }) [<buffer-size>], [[Control echoing of log messages]]) {
diff --git a/nest/proto.c b/nest/proto.c
index 061205c1..1d480ba2 100644
--- a/nest/proto.c
+++ b/nest/proto.c
@@ -57,7 +57,28 @@ static void channel_feed_end(struct channel *c);
 static void channel_export_stopped(struct rt_export_request *req);
 
 static inline int proto_is_done(struct proto *p)
-{ return (p->proto_state == PS_DOWN) && (p->active_channels == 0); }
+{ return (p->proto_state == PS_DOWN) && proto_is_inactive(p); }
+
+static inline event_list *proto_event_list(struct proto *p)
+{ return p->loop == &main_birdloop ? &global_event_list : birdloop_event_list(p->loop); }
+
+static inline event_list *proto_work_list(struct proto *p)
+{ return p->loop == &main_birdloop ? &global_work_list : birdloop_event_list(p->loop); }
+
+static inline void proto_send_event(struct proto *p)
+{ ev_send(proto_event_list(p), p->event); }
+
+#define PROTO_ENTER_FROM_MAIN(p)    ({ \
+    ASSERT_DIE(birdloop_inside(&main_birdloop)); \
+    struct birdloop *_loop = (p)->loop; \
+    if (_loop != &main_birdloop) birdloop_enter(_loop); \
+    _loop; \
+    })
+
+#define PROTO_LEAVE_FROM_MAIN(loop) ({ if (loop != &main_birdloop) birdloop_leave(loop); })
+
+#define PROTO_LOCKED_FROM_MAIN(p)	for (struct birdloop *_proto_loop = PROTO_ENTER_FROM_MAIN(p); _proto_loop; PROTO_LEAVE_FROM_MAIN(_proto_loop), (_proto_loop = NULL))
+
 
 static inline int channel_is_active(struct channel *c)
 { return (c->channel_state != CS_DOWN); }
@@ -438,7 +459,6 @@ channel_start_import(struct channel *c)
     .dump_req = channel_dump_import_req,
     .log_state_change = channel_import_log_state_change,
     .preimport = channel_preimport,
-    .rte_modify = c->proto->rte_modify,
   };
 
   ASSERT(c->channel_state == CS_UP);
@@ -468,6 +488,7 @@ channel_start_export(struct channel *c)
 
   c->out_req = (struct rt_export_request) {
     .name = rn,
+    .list = proto_work_list(c->proto),
     .addr = c->out_subprefix,
     .addr_mode = c->out_subprefix ? TE_ADDR_IN : TE_ADDR_NONE,
     .trace_routes = c->debug | c->proto->debug,
@@ -514,7 +535,7 @@ channel_check_stopped(struct channel *c)
 	return;
 
       channel_set_state(c, CS_DOWN);
-      ev_schedule(c->proto->event);
+      proto_send_event(c->proto);
 
       break;
     case CS_PAUSE:
@@ -634,6 +655,7 @@ channel_setup_in_table(struct channel *c)
 {
   c->reload_req = (struct rt_export_request) {
     .name = mb_sprintf(c->proto->pool, "%s.%s.import", c->proto->name, c->name),
+    .list = proto_work_list(c->proto),
     .trace_routes = c->debug | c->proto->debug,
     .export_bulk = channel_reload_export_bulk,
     .dump_req = channel_reload_dump_req,
@@ -698,8 +720,6 @@ channel_do_stop(struct channel *c)
 
   CALL(c->channel->shutdown, c);
 
-  /* This have to be done in here, as channel pool is freed before channel_do_down() */
-  c->out_table = NULL;
 }
 
 static void
@@ -721,7 +741,7 @@ channel_do_down(struct channel *c)
 
   /* Schedule protocol shutddown */
   if (proto_is_done(c->proto))
-    ev_schedule(c->proto->event);
+    proto_send_event(c->proto);
 }
 
 void
@@ -1032,17 +1052,34 @@ proto_configure_channel(struct proto *p, struct channel **pc, struct channel_con
   return 1;
 }
 
+static void
+proto_cleanup(struct proto *p)
+{
+  rfree(p->pool);
+  p->pool = NULL;
+
+  p->active = 0;
+  proto_log_state_change(p);
+  proto_rethink_goal(p);
+}
 
 static void
-proto_event(void *ptr)
+proto_loop_stopped(void *ptr)
 {
   struct proto *p = ptr;
 
-  if (p->do_start)
-  {
-    if_feed_baby(p);
-    p->do_start = 0;
-  }
+  birdloop_enter(&main_birdloop);
+
+  p->loop = &main_birdloop;
+  proto_cleanup(p);
+
+  birdloop_leave(&main_birdloop);
+}
+
+static void
+proto_event(void *ptr)
+{
+  struct proto *p = ptr;
 
   if (p->do_stop)
   {
@@ -1052,14 +1089,10 @@ proto_event(void *ptr)
   }
 
   if (proto_is_done(p))
-  {
-    rfree(p->pool);
-    p->pool = NULL;
-
-    p->active = 0;
-    proto_log_state_change(p);
-    proto_rethink_goal(p);
-  }
+    if (p->loop != &main_birdloop)
+      birdloop_stop_self(p->loop, proto_loop_stopped, p);
+    else
+      proto_cleanup(p);
 }
 
 
@@ -1100,6 +1133,7 @@ proto_init(struct proto_config *c, node *n)
   struct protocol *pr = c->protocol;
   struct proto *p = pr->init(c);
 
+  p->loop = &main_birdloop;
   p->proto_state = PS_DOWN;
   p->last_state_change = current_time();
   p->vrf = c->vrf;
@@ -1116,11 +1150,19 @@ proto_init(struct proto_config *c, node *n)
 static void
 proto_start(struct proto *p)
 {
-  /* Here we cannot use p->cf->name since it won't survive reconfiguration */
-  p->pool = rp_new(proto_pool, p->proto->name);
+  DBG("Kicking %s up\n", p->name);
+  PD(p, "Starting");
+
+  p->pool = rp_newf(proto_pool, "Protocol %s", p->cf->name);
 
   if (graceful_restart_state == GRS_INIT)
     p->gr_recovery = 1;
+
+  if (p->cf->loop_order != DOMAIN_ORDER(the_bird))
+    p->loop = birdloop_new(p->pool, p->cf->loop_order, p->pool->name);
+
+  PROTO_LOCKED_FROM_MAIN(p)
+    proto_notify_state(p, (p->proto->start ? p->proto->start(p) : PS_UP));
 }
 
 
@@ -1156,6 +1198,7 @@ proto_config_new(struct protocol *pr, int class)
   cf->class = class;
   cf->debug = new_config->proto_default_debug;
   cf->mrtdump = new_config->proto_default_mrtdump;
+  cf->loop_order = DOMAIN_ORDER(the_bird);
 
   init_list(&cf->channels);
 
@@ -1445,11 +1488,20 @@ protos_commit(struct config *new, struct config *old, int force_reconfig, int ty
 }
 
 static void
-proto_rethink_goal(struct proto *p)
+proto_shutdown(struct proto *p)
 {
-  struct protocol *q;
-  byte goal;
+  if (p->proto_state == PS_START || p->proto_state == PS_UP)
+  {
+    /* Going down */
+    DBG("Kicking %s down\n", p->name);
+    PD(p, "Shutting down");
+    proto_notify_state(p, (p->proto->shutdown ? p->proto->shutdown(p) : PS_DOWN));
+  }
+}
 
+static void
+proto_rethink_goal(struct proto *p)
+{
   if (p->reconfiguring && !p->active)
   {
     struct proto_config *nc = p->cf_new;
@@ -1469,32 +1521,12 @@ proto_rethink_goal(struct proto *p)
 
   /* Determine what state we want to reach */
   if (p->disabled || p->reconfiguring)
-    goal = PS_DOWN;
-  else
-    goal = PS_UP;
-
-  q = p->proto;
-  if (goal == PS_UP)
-  {
-    if (!p->active)
-    {
-      /* Going up */
-      DBG("Kicking %s up\n", p->name);
-      PD(p, "Starting");
-      proto_start(p);
-      proto_notify_state(p, (q->start ? q->start(p) : PS_UP));
-    }
-  }
-  else
   {
-    if (p->proto_state == PS_START || p->proto_state == PS_UP)
-    {
-      /* Going down */
-      DBG("Kicking %s down\n", p->name);
-      PD(p, "Shutting down");
-      proto_notify_state(p, (q->shutdown ? q->shutdown(p) : PS_DOWN));
-    }
+    PROTO_LOCKED_FROM_MAIN(p)
+      proto_shutdown(p);
   }
+  else if (!p->active)
+    proto_start(p);
 }
 
 struct proto *
@@ -1699,7 +1731,7 @@ protos_dump_all(void)
 #define DPF(x)	(p->x ? " " #x : "")
     debug("  protocol %s (%p) state %s with %d active channels flags: %s%s%s%s%s\n",
 	p->name, p, p_states[p->proto_state], p->active_channels,
-	DPF(disabled), DPF(active), DPF(do_start), DPF(do_stop), DPF(reconfiguring));
+	DPF(disabled), DPF(active), DPF(do_stop), DPF(reconfiguring));
 #undef DPF
 
     struct channel *c;
@@ -1935,8 +1967,8 @@ static inline void
 proto_do_start(struct proto *p)
 {
   p->active = 1;
-  p->do_start = 1;
-  ev_schedule(p->event);
+  if (!p->cf->late_if_feed)
+    if_feed_baby(p);
 }
 
 static void
@@ -1949,6 +1981,9 @@ proto_do_up(struct proto *p)
   }
 
   proto_start_channels(p);
+
+  if (p->cf->late_if_feed)
+    if_feed_baby(p);
 }
 
 static inline void
@@ -1963,9 +1998,6 @@ proto_do_stop(struct proto *p)
   p->down_sched = 0;
   p->gr_recovery = 0;
 
-  p->do_stop = 1;
-  ev_schedule(p->event);
-
   if (p->main_source)
   {
     rt_unlock_source(p->main_source);
@@ -1973,6 +2005,9 @@ proto_do_stop(struct proto *p)
   }
 
   proto_stop_channels(p);
+
+  p->do_stop = 1;
+  proto_send_event(p);
 }
 
 static void
@@ -1983,7 +2018,7 @@ proto_do_down(struct proto *p)
 
   /* Shutdown is finished in the protocol event */
   if (proto_is_done(p))
-    ev_schedule(p->event);
+    proto_send_event(p);
 }
 
 
@@ -2222,7 +2257,7 @@ proto_cmd_disable(struct proto *p, uintptr_t arg, int cnt UNUSED)
   p->disabled = 1;
   p->down_code = PDC_CMD_DISABLE;
   proto_set_message(p, (char *) arg, -1);
-  proto_rethink_goal(p);
+  proto_shutdown(p);
   cli_msg(-9, "%s: disabled", p->name);
 }
 
@@ -2255,9 +2290,9 @@ proto_cmd_restart(struct proto *p, uintptr_t arg, int cnt UNUSED)
   p->disabled = 1;
   p->down_code = PDC_CMD_RESTART;
   proto_set_message(p, (char *) arg, -1);
-  proto_rethink_goal(p);
+  proto_shutdown(p);
   p->disabled = 0;
-  proto_rethink_goal(p);
+  /* After the protocol shuts down, proto_rethink_goal() is run from proto_event. */
   cli_msg(-12, "%s: restarted", p->name);
 }
 
@@ -2332,7 +2367,9 @@ proto_apply_cmd_symbol(const struct symbol *s, void (* cmd)(struct proto *, uint
 
   if (s->proto->proto)
   {
-    cmd(s->proto->proto, arg, 0);
+    struct proto *p = s->proto->proto;
+    PROTO_LOCKED_FROM_MAIN(p)
+      cmd(p, arg, 0);
     cli_msg(0, "");
   }
   else
@@ -2347,7 +2384,8 @@ proto_apply_cmd_patt(const char *patt, void (* cmd)(struct proto *, uintptr_t, i
 
   WALK_LIST(p, proto_list)
     if (!patt || patmatch(patt, p->name))
-      cmd(p, arg, cnt++);
+      PROTO_LOCKED_FROM_MAIN(p)
+	cmd(p, arg, cnt++);
 
   if (!cnt)
     cli_msg(8003, "No protocols match");
diff --git a/nest/protocol.h b/nest/protocol.h
index 3ccd364a..3c823ae1 100644
--- a/nest/protocol.h
+++ b/nest/protocol.h
@@ -102,8 +102,10 @@ struct proto_config {
   u8 net_type;				/* Protocol network type (NET_*), 0 for undefined */
   u8 disabled;				/* Protocol enabled/disabled by default */
   u8 vrf_set;				/* Related VRF instance (below) is defined */
+  u8 late_if_feed;			/* Delay interface feed after channels are up */
   u32 debug, mrtdump;			/* Debugging bitfields, both use D_* constants */
   u32 router_id;			/* Protocol specific router ID */
+  uint loop_order;			/* Launch a birdloop on this locking level; use DOMAIN_ORDER(the_bird) for mainloop */
 
   list channels;			/* List of channel configs (struct channel_config) */
   struct iface *vrf;			/* Related VRF instance, NULL if global */
@@ -121,6 +123,7 @@ struct proto {
   struct proto_config *cf_new;		/* Configuration we want to switch to after shutdown (NULL=delete) */
   pool *pool;				/* Pool containing local objects */
   event *event;				/* Protocol event */
+  struct birdloop *loop;		/* BIRDloop running this protocol */
 
   list channels;			/* List of channels to rtables (struct channel) */
   struct channel *main_channel;		/* Primary channel */
@@ -131,12 +134,12 @@ struct proto {
   u32 debug;				/* Debugging flags */
   u32 mrtdump;				/* MRTDump flags */
   uint active_channels;			/* Number of active channels */
+  uint active_loops;			/* Number of active IO loops */
   byte net_type;			/* Protocol network type (NET_*), 0 for undefined */
   byte disabled;			/* Manually disabled */
   byte vrf_set;				/* Related VRF instance (above) is defined */
   byte proto_state;			/* Protocol state machine (PS_*, see below) */
   byte active;				/* From PS_START to cleanup after PS_STOP */
-  byte do_start;			/* Start actions are scheduled */
   byte do_stop;				/* Stop actions are scheduled */
   byte reconfiguring;			/* We're shutting down due to reconfiguration */
   byte gr_recovery;			/* Protocol should participate in graceful restart recovery */
@@ -189,7 +192,6 @@ struct proto {
   int (*rte_recalculate)(struct rtable *, struct network *, struct rte *, struct rte *, struct rte *);
   int (*rte_better)(struct rte *, struct rte *);
   int (*rte_mergable)(struct rte *, struct rte *);
-  struct rte *(*rte_modify)(struct rte *, struct linpool *);
   void (*rte_insert)(struct network *, struct rte *);
   void (*rte_remove)(struct network *, struct rte *);
   u32 (*rte_igp_metric)(const struct rte *);
@@ -339,6 +341,8 @@ void proto_notify_state(struct proto *p, unsigned state);
  *	as a result of received ROUTE-REFRESH request).
  */
 
+static inline int proto_is_inactive(struct proto *p)
+{ return (p->active_channels == 0) && (p->active_loops == 0); }
 
 
 /*
diff --git a/nest/rt-show.c b/nest/rt-show.c
index c3294518..b784bf83 100644
--- a/nest/rt-show.c
+++ b/nest/rt-show.c
@@ -77,7 +77,11 @@ rt_show_rte(struct cli *c, byte *ia, rte *e, struct rt_show_data *d, int primary
       e->src->proto->name, tm, from, primary ? (sync_error ? " !" : " *") : "", info);
 
   if (d->verbose)
+  {
     ea_show_list(c, a);
+    cli_printf(c, -1008, "\tInternal route handling values: %uL %uG %uS id %u",
+	e->src->private_id, e->src->global_id, e->stale_cycle, e->id);
+  }
   else if (dest == RTD_UNICAST)
     ea_show_nexthop_list(c, nhad);
   else if (had)
@@ -256,6 +260,18 @@ rt_show_dump_req(struct rt_export_request *req)
 }
 
 static void
+rt_show_done(struct rt_show_data *d)
+{
+  /* No more action */
+  d->cli->cleanup = NULL;
+  d->cli->cont = NULL;
+  d->cli->rover = NULL;
+
+  /* Write pending messages */
+  cli_write_trigger(d->cli);
+}
+
+static void
 rt_show_cont(struct rt_show_data *d)
 {
   struct cli *c = d->cli;
@@ -263,18 +279,13 @@ rt_show_cont(struct rt_show_data *d)
   if (d->running_on_config && (d->running_on_config != config))
   {
     cli_printf(c, 8004, "Stopped due to reconfiguration");
-
-    /* No more action */
-    c->cleanup = NULL;
-    c->cont = NULL;
-    c->rover = NULL;
-    cli_write_trigger(c);
-    return;
+    return rt_show_done(d);
   }
 
   d->req = (struct rt_export_request) {
     .addr = d->addr,
     .name = "CLI Show Route",
+    .list = &global_work_list,
     .export_bulk = rt_show_net_export_bulk,
     .dump_req = rt_show_dump_req,
     .log_state_change = rt_show_log_state_change,
@@ -316,7 +327,6 @@ rt_show_export_stopped(struct rt_export_request *req)
   if (NODE_VALID(d->tab))
     return rt_show_cont(d);
 
-
   /* Printout total stats */
   if (d->stats && (d->table_counter > 1))
   {
@@ -329,7 +339,8 @@ rt_show_export_stopped(struct rt_export_request *req)
   else
     cli_printf(d->cli, 0, "");
 
-  cli_write_trigger(d->cli);
+  /* No more route showing */
+  rt_show_done(d);
 }
 
 struct rt_show_data_rtable *
diff --git a/nest/rt-table.c b/nest/rt-table.c
index 29690414..15dbc371 100644
--- a/nest/rt-table.c
+++ b/nest/rt-table.c
@@ -110,6 +110,8 @@
 #include "proto/bgp/bgp.h"
 #endif
 
+#include <stdatomic.h>
+
 pool *rt_table_pool;
 
 static linpool *rte_update_pool;
@@ -117,6 +119,18 @@ static linpool *rte_update_pool;
 list routing_tables;
 list deleted_routing_tables;
 
+struct rt_cork rt_cork;
+
+/* Data structures for export journal */
+#define RT_PENDING_EXPORT_ITEMS		(page_size - sizeof(struct rt_export_block)) / sizeof(struct rt_pending_export)
+
+struct rt_export_block {
+  node n;
+  _Atomic u32 end;
+  _Atomic _Bool not_last;
+  struct rt_pending_export export[];
+};
+
 static void rt_free_hostcache(rtable *tab);
 static void rt_notify_hostcache(rtable *tab, net *net);
 static void rt_update_hostcache(rtable *tab);
@@ -126,11 +140,23 @@ static inline void rt_flowspec_resolve_rte(rte *r, struct channel *c);
 static inline void rt_prune_table(rtable *tab);
 static inline void rt_schedule_notify(rtable *tab);
 static void rt_flowspec_notify(rtable *tab, net *net);
+static void rt_kick_prune_timer(rtable *tab);
 static void rt_feed_by_fib(void *);
 static void rt_feed_by_trie(void *);
 static void rt_feed_equal(void *);
 static void rt_feed_for(void *);
 static uint rt_feed_net(struct rt_export_hook *c, net *n);
+static void rt_check_cork_low(rtable *tab);
+static void rt_check_cork_high(rtable *tab);
+static void rt_cork_release_hook(void *);
+
+static inline void rt_export_used(struct rt_exporter *);
+static void rt_export_cleanup(rtable *tab);
+
+static inline void rte_update_lock(void);
+static inline void rte_update_unlock(void);
+
+static int rte_same(rte *x, rte *y);
 
 const char *rt_import_state_name_array[TIS_MAX] = {
   [TIS_DOWN] = "DOWN",
@@ -684,8 +710,9 @@ rte_mergable(rte *pri, rte *sec)
 static void
 rte_trace(const char *name, const rte *e, int dir, const char *msg)
 {
-  log(L_TRACE "%s %c %s %N %uL %uG %s",
-      name, dir, msg, e->net, e->src->private_id, e->src->global_id,
+  log(L_TRACE "%s %c %s %N src %uL %uG %uS id %u %s",
+      name, dir, msg, e->net,
+      e->src->private_id, e->src->global_id, e->stale_cycle, e->id,
       rta_dest_name(rte_dest(e)));
 }
 
@@ -725,8 +752,8 @@ rte_feed_count(net *n)
 {
   uint count = 0;
   for (struct rte_storage *e = n->routes; e; e = e->next)
-    if (rte_is_valid(RTE_OR_NULL(e)))
-      count++;
+    count++;
+
   return count;
 }
 
@@ -735,11 +762,11 @@ rte_feed_obtain(net *n, struct rte **feed, uint count)
 {
   uint i = 0;
   for (struct rte_storage *e = n->routes; e; e = e->next)
-    if (rte_is_valid(RTE_OR_NULL(e)))
     {
       ASSERT_DIE(i < count);
       feed[i++] = &e->rte;
     }
+
   ASSERT_DIE(i == count);
 }
 
@@ -847,6 +874,16 @@ do_rt_notify(struct channel *c, const net_addr *net, rte *new, const rte *old)
 static void
 rt_notify_basic(struct channel *c, const net_addr *net, rte *new, rte *old)
 {
+  if (new && old && rte_same(new, old))
+  {
+    if ((new->id != old->id) && bmap_test(&c->export_map, old->id))
+    {
+      bmap_set(&c->export_map, new->id);
+      bmap_clear(&c->export_map, old->id);
+    }
+    return;
+  }
+
   if (new)
     new = export_filter(c, new, 0);
 
@@ -859,6 +896,16 @@ rt_notify_basic(struct channel *c, const net_addr *net, rte *new, rte *old)
   do_rt_notify(c, net, new, old);
 }
 
+static void
+channel_rpe_mark_seen(struct rt_export_request *req, struct rt_pending_export *rpe)
+{
+  struct channel *c = SKIP_BACK(struct channel, out_req, req);
+
+  rpe_mark_seen(req->hook, rpe);
+  if (rpe->old)
+    bmap_clear(&c->export_reject_map, rpe->old->rte.id);
+}
+
 void
 rt_notify_accepted(struct rt_export_request *req, const net_addr *n, struct rt_pending_export *rpe,
     struct rte **feed, uint count)
@@ -902,38 +949,30 @@ rt_notify_accepted(struct rt_export_request *req, const net_addr *n, struct rt_p
     }
   }
 
+done:
   /* Check obsolete routes for previously exported */
-  if (!old_best)
-    if (rpe && rpe->old && bmap_test(&c->export_map, rpe->old->rte.id))
-      old_best = &rpe->old->rte;
-
-/*    for (; rpe; rpe = atomic_load_explicit(&rpe->next, memory_order_relaxed))
+  while (rpe)
+  {
+    channel_rpe_mark_seen(req, rpe);
+    if (rpe->old)
     {
-      if (rpe->old && bmap_test(&hook->accept_map, rpe->old->id))
+      if (bmap_test(&c->export_map, rpe->old->rte.id))
       {
-	old_best = &rpe->old.rte;
-	break;
+	ASSERT_DIE(old_best == NULL);
+	old_best = &rpe->old->rte;
       }
-
-      if (rpe == rpe_last)
-	break;
     }
-    */
+    rpe = rpe_next(rpe, NULL);
+  }
 
   /* Nothing to export */
   if (!new_best && !old_best)
   {
     DBG("rt_notify_accepted: nothing to export\n");
-    goto done;
+    return;
   }
 
   do_rt_notify(c, n, new_best, old_best);
-
-done:
-  /* Drop the old stored rejection if applicable.
-   * new->id == old->id happens when updating hostentries. */
-  if (rpe && rpe->old && (!rpe->new || (rpe->new->rte.id != rpe->old->rte.id)))
-    bmap_clear(&c->export_reject_map, rpe->old->rte.id);
 }
 
 rte *
@@ -1025,63 +1064,74 @@ rt_notify_merged(struct rt_export_request *req, const net_addr *n, struct rt_pen
     }
 
   /* Check obsolete routes for previously exported */
-  if (!old_best)
-    if (rpe && rpe->old && bmap_test(&c->export_map, rpe->old->rte.id))
-      old_best = &rpe->old->rte;
-
-/*    for (; rpe; rpe = atomic_load_explicit(&rpe->next, memory_order_relaxed))
+  while (rpe)
+  {
+    channel_rpe_mark_seen(req, rpe);
+    if (rpe->old)
     {
-      if (rpe->old && bmap_test(&hook->accept_map, rpe->old->id))
+      if (bmap_test(&c->export_map, rpe->old->rte.id))
       {
-	old_best = &rpe->old.rte;
-	break;
+	ASSERT_DIE(old_best == NULL);
+	old_best = &rpe->old->rte;
       }
-
-      if (rpe == rpe_last)
-	break;
     }
-    */
+    rpe = rpe_next(rpe, NULL);
+  }
 
   /* Prepare new merged route */
   rte *new_merged = count ? rt_export_merged(c, feed, count, rte_update_pool, 0) : NULL;
 
   if (new_merged || old_best)
     do_rt_notify(c, n, new_merged, old_best);
-
-  /* Drop the old stored rejection if applicable.
-   * new->id == old->id happens when updating hostentries. */
-  if (rpe && rpe->old && (!rpe->new || (rpe->new->rte.id != rpe->old->rte.id)))
-    bmap_clear(&c->export_reject_map, rpe->old->rte.id);
 }
 
 void
 rt_notify_optimal(struct rt_export_request *req, const net_addr *net, struct rt_pending_export *rpe)
 {
   struct channel *c = SKIP_BACK(struct channel, out_req, req);
-  rte n0;
 
-  if (rpe->new_best != rpe->old_best)
-    rt_notify_basic(c, net, RTE_COPY(rpe->new_best, &n0), RTE_OR_NULL(rpe->old_best));
+  rte *o = RTE_VALID_OR_NULL(rpe->old_best);
+  struct rte_storage *new_best = rpe->new_best;
 
-  /* Drop the old stored rejection if applicable.
-   * new->id == old->id happens when updating hostentries. */
-  if (rpe->old && (!rpe->new || (rpe->new->rte.id != rpe->old->rte.id)))
-    bmap_clear(&c->export_reject_map, rpe->old->rte.id);
+  while (rpe)
+  {
+    channel_rpe_mark_seen(req, rpe);
+    new_best = rpe->new_best;
+    rpe = rpe_next(rpe, NULL);
+  }
+
+  rte n0 = RTE_COPY_VALID(new_best);
+  if (n0.src || o)
+    rt_notify_basic(c, net, n0.src ? &n0 : NULL, o);
 }
 
 void
 rt_notify_any(struct rt_export_request *req, const net_addr *net, struct rt_pending_export *rpe)
 {
   struct channel *c = SKIP_BACK(struct channel, out_req, req);
-  rte n0;
 
-  if (rpe->new != rpe->old)
-    rt_notify_basic(c, net, RTE_COPY(rpe->new, &n0), RTE_OR_NULL(rpe->old));
+  rte *n = RTE_VALID_OR_NULL(rpe->new);
+  rte *o = RTE_VALID_OR_NULL(rpe->old);
 
-  /* Drop the old stored rejection if applicable.
-   * new->id == old->id happens when updating hostentries. */
-  if (rpe->old && (!rpe->new || (rpe->new->rte.id != rpe->old->rte.id)))
-    bmap_clear(&c->export_reject_map, rpe->old->rte.id);
+  if (!n && !o)
+  {
+    channel_rpe_mark_seen(req, rpe);
+    return;
+  }
+
+  struct rte_src *src = n ? n->src : o->src;
+  struct rte_storage *new_latest = rpe->new;
+
+  while (rpe)
+  {
+    channel_rpe_mark_seen(req, rpe);
+    new_latest = rpe->new;
+    rpe = rpe_next(rpe, src);
+  }
+
+  rte n0 = RTE_COPY_VALID(new_latest);
+  if (n0.src || o)
+    rt_notify_basic(c, net, n0.src ? &n0 : NULL, o);
 }
 
 void
@@ -1090,10 +1140,103 @@ rt_feed_any(struct rt_export_request *req, const net_addr *net, struct rt_pendin
   struct channel *c = SKIP_BACK(struct channel, out_req, req);
 
   for (uint i=0; i<count; i++)
+    if (rte_is_valid(feed[i]))
+    {
+      rte n0 = *feed[i];
+      rt_notify_basic(c, net, &n0, NULL);
+    }
+}
+
+void
+rpe_mark_seen(struct rt_export_hook *hook, struct rt_pending_export *rpe)
+{
+  bmap_set(&hook->seq_map, rpe->seq);
+}
+
+struct rt_pending_export *
+rpe_next(struct rt_pending_export *rpe, struct rte_src *src)
+{
+  struct rt_pending_export *next = atomic_load_explicit(&rpe->next, memory_order_acquire);
+
+  if (!next)
+    return NULL;
+
+  if (!src)
+    return next;
+
+  while (rpe = next)
+    if (src == (rpe->new ? rpe->new->rte.src : rpe->old->rte.src))
+      return rpe;
+    else
+      next = atomic_load_explicit(&rpe->next, memory_order_acquire);
+
+  return NULL;
+}
+
+static struct rt_pending_export * rt_next_export_fast(struct rt_pending_export *last);
+static void
+rte_export(struct rt_export_hook *hook, struct rt_pending_export *rpe)
+{
+  if (bmap_test(&hook->seq_map, rpe->seq))
+    goto ignore;	/* Seen already */
+
+  const net_addr *n = rpe->new_best ? rpe->new_best->rte.net : rpe->old_best->rte.net;
+
+  switch (hook->req->addr_mode)
+    {
+      case TE_ADDR_NONE:
+	break;
+
+      case TE_ADDR_IN:
+	if (!net_in_netX(n, hook->req->addr))
+	  goto ignore;
+	break;
+
+      case TE_ADDR_EQUAL:
+	if (!net_equal(n, hook->req->addr))
+	  goto ignore;
+	break;
+
+      case TE_ADDR_FOR:
+	bug("Continuos export of best prefix match not implemented yet.");
+
+      default:
+	bug("Strange table export address mode: %d", hook->req->addr_mode);
+    }
+
+  if (rpe->new)
+    hook->stats.updates_received++;
+  else
+    hook->stats.withdraws_received++;
+
+  if (hook->req->export_one)
+    hook->req->export_one(hook->req, n, rpe);
+  else if (hook->req->export_bulk)
   {
-    rte n0 = *feed[i];
-    rt_notify_basic(c, net, &n0, NULL);
+    net *net = SKIP_BACK(struct network, n.addr, (net_addr (*)[0]) n);
+    uint count = rte_feed_count(net);
+    rte **feed = NULL;
+    if (count)
+    {
+      feed = alloca(count * sizeof(rte *));
+      rte_feed_obtain(net, feed, count);
+    }
+    hook->req->export_bulk(hook->req, n, rpe, feed, count);
   }
+  else
+    bug("Export request must always provide an export method");
+
+ignore:
+  /* Get the next export if exists */
+  hook->rpe_next = rt_next_export_fast(rpe);
+
+  /* The last block may be available to free */
+  if (PAGE_HEAD(hook->rpe_next) != PAGE_HEAD(rpe))
+    CALL(hook->table->used, hook->table);
+
+  /* Releasing this export for cleanup routine */
+  DBG("store hook=%p last_export=%p seq=%lu\n", hook, rpe, rpe->seq);
+  atomic_store_explicit(&hook->last_export, rpe, memory_order_release);
 }
 
 /**
@@ -1131,26 +1274,17 @@ static void
 rte_announce(rtable *tab, net *net, struct rte_storage *new, struct rte_storage *old,
 	     struct rte_storage *new_best, struct rte_storage *old_best)
 {
-  if (!rte_is_valid(RTE_OR_NULL(new)))
-    new = NULL;
-
-  if (!rte_is_valid(RTE_OR_NULL(old)))
-    old = NULL;
+  int new_best_valid = rte_is_valid(RTE_OR_NULL(new_best));
+  int old_best_valid = rte_is_valid(RTE_OR_NULL(old_best));
 
-  if (!rte_is_valid(RTE_OR_NULL(new_best)))
-    new_best = NULL;
-
-  if (!rte_is_valid(RTE_OR_NULL(old_best)))
-    old_best = NULL;
-
-  if (!new && !old && !new_best && !old_best)
+  if ((new == old) && (new_best == old_best))
     return;
 
-  if (new_best != old_best)
+  if (new_best_valid || old_best_valid)
   {
-    if (new_best)
+    if (new_best_valid)
       new_best->rte.sender->stats.pref++;
-    if (old_best)
+    if (old_best_valid)
       old_best->rte.sender->stats.pref--;
 
     if (tab->hostcache)
@@ -1162,57 +1296,206 @@ rte_announce(rtable *tab, net *net, struct rte_storage *new, struct rte_storage
 
   rt_schedule_notify(tab);
 
-  struct rt_pending_export rpe = { .new = new, .old = old, .new_best = new_best, .old_best = old_best };
-  uint count = rte_feed_count(net);
-  rte **feed = NULL;
-  if (count)
+  if (EMPTY_LIST(tab->exporter.hooks) && EMPTY_LIST(tab->exporter.pending))
   {
-    feed = alloca(count * sizeof(rte *));
-    rte_feed_obtain(net, feed, count);
+    /* No export hook and no pending exports to cleanup. We may free the route immediately. */
+    if (!old)
+      return;
+
+    hmap_clear(&tab->id_map, old->rte.id);
+    rte_free(old);
+    return;
   }
 
-  struct rt_export_hook *eh;
-  WALK_LIST(eh, tab->exporter.hooks)
+  /* Get the pending export structure */
+  struct rt_export_block *rpeb = NULL, *rpebsnl = NULL;
+  u32 end = 0;
+
+  if (!EMPTY_LIST(tab->exporter.pending))
+  {
+    rpeb = TAIL(tab->exporter.pending);
+    end = atomic_load_explicit(&rpeb->end, memory_order_relaxed);
+    if (end >= RT_PENDING_EXPORT_ITEMS)
+    {
+      ASSERT_DIE(end == RT_PENDING_EXPORT_ITEMS);
+      rpebsnl = rpeb;
+
+      rpeb = NULL;
+      end = 0;
+    }
+  }
+
+  if (!rpeb)
+  {
+    rpeb = alloc_page();
+    *rpeb = (struct rt_export_block) {};
+    add_tail(&tab->exporter.pending, &rpeb->n);
+  }
+
+  /* Fill the pending export */
+  struct rt_pending_export *rpe = &rpeb->export[rpeb->end];
+  *rpe = (struct rt_pending_export) {
+    .new = new,
+    .new_best = new_best,
+    .old = old,
+    .old_best = old_best,
+    .seq = tab->exporter.next_seq++,
+  };
+
+  DBGL("rte_announce: table=%s net=%N new=%p id %u from %s old=%p id %u from %s new_best=%p id %u old_best=%p id %u seq=%lu",
+      tab->name, net->n.addr,
+      new, new ? new->rte.id : 0, new ? new->rte.sender->req->name : NULL,
+      old, old ? old->rte.id : 0, old ? old->rte.sender->req->name : NULL,
+      new_best, old_best, rpe->seq);
+
+  ASSERT_DIE(atomic_fetch_add_explicit(&rpeb->end, 1, memory_order_release) == end);
+
+  if (rpebsnl)
+  {
+    _Bool f = 0;
+    ASSERT_DIE(atomic_compare_exchange_strong_explicit(&rpebsnl->not_last, &f, 1,
+	  memory_order_release, memory_order_relaxed));
+  }
+
+  /* Append to the same-network squasher list */
+  if (net->last)
+  {
+    struct rt_pending_export *rpenull = NULL;
+    ASSERT_DIE(atomic_compare_exchange_strong_explicit(
+	  &net->last->next, &rpenull, rpe,
+	  memory_order_relaxed,
+	  memory_order_relaxed));
+    
+  }
+
+  net->last = rpe;
+
+  if (!net->first)
+    net->first = rpe;
+
+  if (tab->exporter.first == NULL)
+    tab->exporter.first = rpe;
+
+  rt_check_cork_high(tab);
+
+  if (!tm_active(tab->exporter.export_timer))
+    tm_start(tab->exporter.export_timer, tab->config->export_settle_time);
+}
+
+static struct rt_pending_export *
+rt_next_export_fast(struct rt_pending_export *last)
+{
+  /* Get the whole export block and find our position in there. */
+  struct rt_export_block *rpeb = PAGE_HEAD(last);
+  u32 pos = (last - &rpeb->export[0]);
+  u32 end = atomic_load_explicit(&rpeb->end, memory_order_acquire);
+  ASSERT_DIE(pos < end);
+
+  /* Next is in the same block. */
+  if (++pos < end)
+    return &rpeb->export[pos];
+
+  /* There is another block. */
+  if (atomic_load_explicit(&rpeb->not_last, memory_order_acquire))
   {
-    if (eh->export_state == TES_STOP)
+    /* This is OK to do non-atomically because of the not_last flag. */
+    rpeb = NODE_NEXT(rpeb);
+    return &rpeb->export[0];
+  }
+
+  /* There is nothing more. */
+  return NULL;
+}
+
+static struct rt_pending_export *
+rt_next_export(struct rt_export_hook *hook, struct rt_exporter *tab)
+{
+  /* As the table is locked, it is safe to reload the last export pointer */
+  struct rt_pending_export *last = atomic_load_explicit(&hook->last_export, memory_order_acquire);
+
+  /* It is still valid, let's reuse it */
+  if (last)
+    return rt_next_export_fast(last);
+
+  /* No, therefore we must process the table's first pending export */
+  else
+    return tab->first;
+}
+
+static inline void
+rt_send_export_event(struct rt_export_hook *hook)
+{
+  ev_send(hook->req->list, hook->event);
+}
+
+static void
+rt_announce_exports(timer *tm)
+{
+  rtable *tab = tm->data;
+
+  struct rt_export_hook *c; node *n;
+  WALK_LIST2(c, n, tab->exporter.hooks, n)
+  {
+    if (atomic_load_explicit(&c->export_state, memory_order_acquire) != TES_READY)
       continue;
 
-    switch (eh->req->addr_mode)
-    {
-      case TE_ADDR_NONE:
-	break;
+    rt_send_export_event(c);
+  }
+}
 
-      case TE_ADDR_IN:
-	if (!net_in_netX(net->n.addr, eh->req->addr))
-	  continue;
-	break;
+static struct rt_pending_export *
+rt_last_export(struct rt_exporter *tab)
+{
+  struct rt_pending_export *rpe = NULL;
 
-      case TE_ADDR_EQUAL:
-	if (!net_equal(net->n.addr, eh->req->addr))
-	  continue;
-	break;
+  if (!EMPTY_LIST(tab->pending))
+  {
+    /* We'll continue processing exports from this export on */
+    struct rt_export_block *reb = TAIL(tab->pending);
+    ASSERT_DIE(reb->end);
+    rpe = &reb->export[reb->end - 1];
+  }
 
-      case TE_ADDR_FOR:
-	bug("Continuos export of best prefix match not implemented yet.");
+  return rpe;
+}
 
-      default:
-	bug("Strange table export address mode: %d", eh->req->addr_mode);
+#define RT_EXPORT_BULK	1024
+
+static void
+rt_export_hook(void *_data)
+{
+  struct rt_export_hook *c = _data;
+
+  ASSERT_DIE(atomic_load_explicit(&c->export_state, memory_order_relaxed) == TES_READY);
+
+  if (!c->rpe_next)
+  {
+    c->rpe_next = rt_next_export(c, c->table);
+
+    if (!c->rpe_next)
+    {
+      CALL(c->table->used, c->table);
+      return;
     }
+  }
 
-    if (new)
-      eh->stats.updates_received++;
-    else
-      eh->stats.withdraws_received++;
+  /* Process the export */
+  for (uint i=0; i<RT_EXPORT_BULK; i++)
+  {
+    rte_update_lock();
 
-    if (eh->req->export_one)
-      eh->req->export_one(eh->req, net->n.addr, &rpe);
-    else if (eh->req->export_bulk)
-      eh->req->export_bulk(eh->req, net->n.addr, &rpe, feed, count);
-    else
-      bug("Export request must always provide an export method");
+    rte_export(c, c->rpe_next);
+
+    if (!c->rpe_next)
+      break;
+
+    rte_update_unlock();
   }
+
+  rt_send_export_event(c);
 }
 
+
 static inline int
 rte_validate(struct channel *ch, rte *e)
 {
@@ -1322,8 +1605,7 @@ rte_recalculate(struct rt_import_hook *c, net *net, rte *new, struct rte_src *sr
 	  if (new && rte_same(old, &new_stored->rte))
 	    {
 	      /* No changes, ignore the new route and refresh the old one */
-
-	      old->flags &= ~(REF_STALE | REF_DISCARD | REF_MODIFY);
+	      old->stale_cycle = new->stale_cycle;
 
 	      if (!rte_is_filtered(new))
 		{
@@ -1458,14 +1740,8 @@ rte_recalculate(struct rt_import_hook *c, net *net, rte *new, struct rte_src *sr
   if (new_stored)
     {
       new_stored->rte.lastmod = current_time();
-
-      if (!old)
-        {
-	  new_stored->rte.id = hmap_first_zero(&table->id_map);
-	  hmap_set(&table->id_map, new_stored->rte.id);
-	}
-      else
-	new_stored->rte.id = old->id;
+      new_stored->rte.id = hmap_first_zero(&table->id_map);
+      hmap_set(&table->id_map, new_stored->rte.id);
     }
 
   /* Log the route change */
@@ -1486,9 +1762,8 @@ rte_recalculate(struct rt_import_hook *c, net *net, rte *new, struct rte_src *sr
       net->routes, old_best_stored);
 
   if (!net->routes &&
-      (table->gc_counter++ >= table->config->gc_max_ops) &&
-      (table->gc_time + table->config->gc_min_time <= current_time()))
-    rt_schedule_prune(table);
+      (table->gc_counter++ >= table->config->gc_threshold))
+    rt_kick_prune_timer(table);
 
 #if 0
   /* Enable and reimplement these callbacks if anybody wants to use them */
@@ -1498,13 +1773,6 @@ rte_recalculate(struct rt_import_hook *c, net *net, rte *new, struct rte_src *sr
     p->rte_insert(net, &new_stored->rte);
 #endif
 
-  if (old)
-    {
-      if (!new_stored)
-	hmap_clear(&table->id_map, old->id);
-
-      rte_free(old_stored);
-    }
 }
 
 static int rte_update_nest_cnt;		/* Nesting counter to allow recursive updates */
@@ -1639,6 +1907,9 @@ rte_import(struct rt_import_request *req, const net_addr *n, rte *new, struct rt
       nn = net_get(hook->table, n);
       new->net = nn->n.addr;
       new->sender = hook;
+
+      /* Set the stale cycle */
+      new->stale_cycle = hook->stale_set;
     }
   else if (!(nn = net_find(hook->table, n)))
     {
@@ -1669,24 +1940,6 @@ rte_discard(net *net, rte *old)	/* Non-filtered route deletion, used during garb
   rte_update_unlock();
 }
 
-/* Modify existing route by protocol hook, used for long-lived graceful restart */
-static inline void
-rte_modify(net *net, rte *old)
-{
-  rte_update_lock();
-
-  rte *new = old->sender->req->rte_modify(old, rte_update_pool);
-  if (new != old)
-  {
-    if (new)
-      new->flags = old->flags & ~REF_MODIFY;
-
-    rte_recalculate(old->sender, net, new, old->src);
-  }
-
-  rte_update_unlock();
-}
-
 /* Check rtable for best route to given net whether it would be exported do p */
 int
 rt_examine(rtable *t, net_addr *a, struct channel *c, const struct filter *filter)
@@ -1726,16 +1979,19 @@ rt_export_stopped(void *data)
   struct rt_export_hook *hook = data;
   struct rt_exporter *tab = hook->table;
 
+  /* Drop pending exports */
+  CALL(tab->used, tab);
+
   /* Unlist */
   rem_node(&hook->n);
 
-  /* Reporting the channel as stopped. */
+  /* Report the channel as stopped. */
   hook->stopped(hook->req);
 
   /* Reporting the hook as finished. */
   CALL(tab->done, hook);
 
-  /* Freeing the hook together with its coroutine. */
+  /* Free the hook. */
   rfree(hook->pool);
 }
 
@@ -1753,7 +2009,7 @@ void
 rt_set_export_state(struct rt_export_hook *hook, u8 state)
 {
   hook->last_state_change = current_time();
-  hook->export_state = state;
+  atomic_store_explicit(&hook->export_state, state, memory_order_release);
 
   if (hook->req->log_state_change)
     hook->req->log_state_change(hook->req, state);
@@ -1799,7 +2055,6 @@ rt_table_export_start(struct rt_exporter *re, struct rt_export_request *req)
   pool *p = rp_new(tab->rp, "Export hook");
   struct rt_export_hook *hook = mb_allocz(p, sizeof(struct rt_export_hook));
   hook->pool = p;
-  hook->lp = lp_new_default(p);
 
   /* stats zeroed by mb_allocz */
   switch (req->addr_mode)
@@ -1844,12 +2099,18 @@ rt_request_export(struct rt_exporter *re, struct rt_export_request *req)
   hook->req = req;
   hook->table = re;
 
+  bmap_init(&hook->seq_map, hook->pool, 1024);
+
+  struct rt_pending_export *rpe = rt_last_export(hook->table);
+  DBG("store hook=%p last_export=%p seq=%lu\n", hook, rpe, rpe ? rpe->seq : 0);
+  atomic_store_explicit(&hook->last_export, rpe, memory_order_relaxed);
+
   hook->n = (node) {};
   add_tail(&re->hooks, &hook->n);
 
   /* Regular export */
   rt_set_export_state(hook, TES_FEEDING);
-  ev_schedule_work(hook->event);
+  rt_send_export_event(hook);
 }
 
 static void
@@ -1857,7 +2118,7 @@ rt_table_export_stop(struct rt_export_hook *hook)
 {
   rtable *tab = SKIP_BACK(rtable, exporter, hook->table);
 
-  if (hook->export_state != TES_FEEDING)
+  if (atomic_load_explicit(&hook->export_state, memory_order_relaxed) != TES_FEEDING)
     return;
 
   switch (hook->req->addr_mode)
@@ -1898,7 +2159,7 @@ rt_stop_export(struct rt_export_request *req, void (*stopped)(struct rt_export_r
   rt_set_export_state(hook, TES_STOP);
 
   /* Run the stopped event */
-  ev_schedule(hook->event);
+  rt_send_export_event(hook);
 }
 
 /**
@@ -1916,15 +2177,38 @@ rt_stop_export(struct rt_export_request *req, void (*stopped)(struct rt_export_r
  * flag in rt_refresh_end() and then removing such routes in the prune loop.
  */
 void
-rt_refresh_begin(rtable *t, struct rt_import_request *req)
+rt_refresh_begin(struct rt_import_request *req)
 {
-  FIB_WALK(&t->fib, net, n)
-    {
-      for (struct rte_storage *e = n->routes; e; e = e->next)
-	if (e->rte.sender == req->hook)
-	  e->rte.flags |= REF_STALE;
-    }
-  FIB_WALK_END;
+  struct rt_import_hook *hook = req->hook;
+  ASSERT_DIE(hook);
+  ASSERT_DIE(hook->stale_set == hook->stale_valid);
+
+  /* If the pruning routine is too slow */
+  if ((hook->stale_pruned < hook->stale_valid) && (hook->stale_pruned + 128 < hook->stale_valid)
+      || (hook->stale_pruned > hook->stale_valid) && (hook->stale_pruned > hook->stale_valid + 128))
+  {
+    log(L_WARN "Route refresh flood in table %s", hook->table->name);
+    FIB_WALK(&hook->table->fib, net, n)
+      {
+       for (struct rte_storage *e = n->routes; e; e = e->next)
+         if (e->rte.sender == req->hook)
+           e->rte.stale_cycle = 0;
+      }
+    FIB_WALK_END;
+    hook->stale_set = 1;
+    hook->stale_valid = 0;
+    hook->stale_pruned = 0;
+  }
+  /* Setting a new value of the stale modifier */
+  else if (!++hook->stale_set)
+  {
+    /* Let's reserve the stale_cycle zero value for always-invalid routes */
+    hook->stale_set = 1;
+    hook->stale_valid = 0;
+  }
+
+  if (req->trace_routes & D_STATES)
+    log(L_TRACE "%s: route refresh begin [%u]", req->name, hook->stale_set);
 }
 
 /**
@@ -1936,43 +2220,18 @@ rt_refresh_begin(rtable *t, struct rt_import_request *req)
  * hook. See rt_refresh_begin() for description of refresh cycles.
  */
 void
-rt_refresh_end(rtable *t, struct rt_import_request *req)
+rt_refresh_end(struct rt_import_request *req)
 {
-  int prune = 0;
-
-  FIB_WALK(&t->fib, net, n)
-    {
-      for (struct rte_storage *e = n->routes; e; e = e->next)
-	if ((e->rte.sender == req->hook) && (e->rte.flags & REF_STALE))
-	  {
-	    e->rte.flags |= REF_DISCARD;
-	    prune = 1;
-	  }
-    }
-  FIB_WALK_END;
-
-  if (prune)
-    rt_schedule_prune(t);
-}
+  struct rt_import_hook *hook = req->hook;
+  ASSERT_DIE(hook);
 
-void
-rt_modify_stale(rtable *t, struct rt_import_request *req)
-{
-  int prune = 0;
+  hook->stale_valid++;
+  ASSERT_DIE(hook->stale_set == hook->stale_valid);
 
-  FIB_WALK(&t->fib, net, n)
-    {
-      for (struct rte_storage *e = n->routes; e; e = e->next)
-	if ((e->rte.sender == req->hook) && (e->rte.flags & REF_STALE) && !(e->rte.flags & REF_FILTERED))
-	  {
-	    e->rte.flags |= REF_MODIFY;
-	    prune = 1;
-	  }
-    }
-  FIB_WALK_END;
+  rt_schedule_prune(hook->table);
 
-  if (prune)
-    rt_schedule_prune(t);
+  if (req->trace_routes & D_STATES)
+    log(L_TRACE "%s: route refresh end [%u]", req->name, hook->stale_valid);
 }
 
 /**
@@ -2054,8 +2313,8 @@ rt_dump_hooks(rtable *tab)
   {
     eh->req->dump_req(eh->req);
     debug("  Export hook %p requested by %p:"
-       " refeed_pending=%u last_state_change=%t export_state=%u stopped=%p\n",
-       eh, eh->req, eh->refeed_pending, eh->last_state_change, eh->export_state, eh->stopped);
+       " refeed_pending=%u last_state_change=%t export_state=%u\n",
+       eh, eh->req, eh->refeed_pending, eh->last_state_change, atomic_load_explicit(&eh->export_state, memory_order_relaxed));
   }
   debug("\n");
 }
@@ -2108,6 +2367,20 @@ rt_schedule_prune(rtable *tab)
   tab->prune_state |= 1;
 }
 
+static void
+rt_export_used(struct rt_exporter *e)
+{
+  rtable *tab = SKIP_BACK(rtable, exporter, e);
+
+  if (config->table_debug)
+    log(L_TRACE "%s: Export cleanup requested", tab->name);
+
+  if (tab->export_used)
+    return;
+
+  tab->export_used = 1;
+  ev_schedule(tab->rt_event);
+}
 
 static void
 rt_event(void *ptr)
@@ -2116,6 +2389,25 @@ rt_event(void *ptr)
 
   rt_lock_table(tab);
 
+  if (tab->export_used)
+    rt_export_cleanup(tab);
+
+  if (
+      tab->hcu_corked ||
+      tab->nhu_corked ||
+      (tab->hcu_scheduled || tab->nhu_state) && rt_cork_check(tab->uncork_event)
+      )
+  {
+    if (!tab->hcu_corked && !tab->nhu_corked && config->table_debug)
+      log(L_TRACE "%s: Auxiliary routines corked", tab->name);
+
+    tab->hcu_corked |= tab->hcu_scheduled;
+    tab->hcu_scheduled = 0;
+
+    tab->nhu_corked |= tab->nhu_state;
+    tab->nhu_state = 0;
+  }
+
   if (tab->hcu_scheduled)
     rt_update_hostcache(tab);
 
@@ -2128,6 +2420,45 @@ rt_event(void *ptr)
   rt_unlock_table(tab);
 }
 
+static void
+rt_uncork_event(void *ptr)
+{
+  rtable *tab = ptr;
+
+  tab->hcu_scheduled |= tab->hcu_corked;
+  tab->hcu_corked = 0;
+
+  tab->nhu_state |= tab->nhu_corked;
+  tab->nhu_corked = 0;
+
+  if (config->table_debug)
+    log(L_TRACE "%s: Auxiliary routines uncorked", tab->name);
+
+  ev_schedule(tab->rt_event);
+}
+
+static void
+rt_prune_timer(timer *t)
+{
+  rtable *tab = t->data;
+
+  if (tab->gc_counter >= tab->config->gc_threshold)
+    rt_schedule_prune(tab);
+}
+
+static void
+rt_kick_prune_timer(rtable *tab)
+{
+  /* Return if prune is already scheduled */
+  if (tm_active(tab->prune_timer) || (tab->prune_state & 1))
+    return;
+
+  /* Randomize GC period to +/- 50% */
+  btime gc_period = tab->config->gc_period;
+  gc_period = (gc_period / 2) + (random_u32() % (uint) gc_period);
+  tm_start(tab->prune_timer, gc_period);
+}
+
 
 static inline btime
 rt_settled_time(rtable *tab)
@@ -2293,9 +2624,6 @@ rt_free(resource *_r)
   DBG("Deleting routing table %s\n", r->name);
   ASSERT_DIE(r->use_count == 0);
 
-  if (r->internal)
-    return;
-
   r->config->table = NULL;
   rem_node(&r->n);
 
@@ -2359,28 +2687,34 @@ rt_setup(pool *pp, struct rtable_config *cf)
     .start = rt_table_export_start,
     .stop = rt_table_export_stop,
     .done = rt_table_export_done,
+    .used = rt_export_used,
   };
+
   init_list(&t->exporter.hooks);
+  init_list(&t->exporter.pending);
 
-  if (!(t->internal = cf->internal))
-  {
-    init_list(&t->imports);
+  init_list(&t->imports);
 
-    hmap_init(&t->id_map, p, 1024);
-    hmap_set(&t->id_map, 0);
+  hmap_init(&t->id_map, p, 1024);
+  hmap_set(&t->id_map, 0);
 
-    init_list(&t->subscribers);
+  init_list(&t->subscribers);
 
-    t->rt_event = ev_new_init(p, rt_event, t);
-    t->last_rt_change = t->gc_time = current_time();
+  t->rt_event = ev_new_init(p, rt_event, t);
+  t->uncork_event = ev_new_init(p, rt_uncork_event, t);
+  t->prune_timer = tm_new_init(p, rt_prune_timer, t, 0, 0);
+  t->exporter.export_timer = tm_new_init(p, rt_announce_exports, t, 0, 0);
+  t->last_rt_change = t->gc_time = current_time();
+  t->exporter.next_seq = 1;
 
-    t->rl_pipe = (struct tbf) TBF_DEFAULT_LOG_LIMITS;
+  t->cork_threshold = cf->cork_threshold;
 
-    if (rt_is_flow(t))
-    {
-      t->flowspec_trie = f_new_trie(lp_new_default(p), 0);
-      t->flowspec_trie->ipv4 = (t->addr_type == NET_FLOW4);
-    }
+  t->rl_pipe = (struct tbf) TBF_DEFAULT_LOG_LIMITS;
+
+  if (rt_is_flow(t))
+  {
+    t->flowspec_trie = f_new_trie(lp_new_default(p), 0);
+    t->flowspec_trie->ipv4 = (t->addr_type == NET_FLOW4);
   }
 
   return t;
@@ -2400,6 +2734,8 @@ rt_init(void)
   rte_update_pool = lp_new_default(rt_table_pool);
   init_list(&routing_tables);
   init_list(&deleted_routing_tables);
+  ev_init_list(&rt_cork.queue, &main_birdloop, "Route cork release");
+  rt_cork.run = (event) { .hook = rt_cork_release_hook };
 }
 
 
@@ -2440,10 +2776,20 @@ rt_prune_table(rtable *tab)
     WALK_LIST2(ih, n, tab->imports, n)
       if (ih->import_state == TIS_STOP)
 	rt_set_import_state(ih, TIS_FLUSHING);
+      else if ((ih->stale_valid != ih->stale_pruning) && (ih->stale_pruning == ih->stale_pruned))
+      {
+	ih->stale_pruning = ih->stale_valid;
+
+	if (ih->req->trace_routes & D_STATES)
+	  log(L_TRACE "%s: table prune after refresh begin [%u]", ih->req->name, ih->stale_pruning);
+      }
 
     FIB_ITERATE_INIT(fit, &tab->fib);
     tab->prune_state = 2;
 
+    tab->gc_counter = 0;
+    tab->gc_time = current_time();
+
     if (tab->prune_trie)
     {
       /* Init prefix trie pruning */
@@ -2465,24 +2811,19 @@ again:
 
       for (struct rte_storage *e=n->routes; e; e=e->next)
       {
-	if ((e->rte.sender->import_state == TIS_FLUSHING) || (e->rte.flags & REF_DISCARD))
+	struct rt_import_hook *s = e->rte.sender;
+	if ((s->import_state == TIS_FLUSHING) ||
+	    (e->rte.stale_cycle < s->stale_valid) ||
+	    (e->rte.stale_cycle > s->stale_set))
 	  {
 	    rte_discard(n, &e->rte);
 	    limit--;
 
 	    goto rescan;
 	  }
-
-	if (e->rte.flags & REF_MODIFY)
-	  {
-	    rte_modify(n, &e->rte);
-	    limit--;
-
-	    goto rescan;
-	  }
       }
 
-      if (!n->routes)		/* Orphaned FIB entry */
+      if (!n->routes && !n->first)		/* Orphaned FIB entry */
 	{
 	  FIB_ITERATE_PUT(fit);
 	  fib_delete(&tab->fib, n);
@@ -2501,9 +2842,6 @@ again:
   fib_check(&tab->fib);
 #endif
 
-  tab->gc_counter = 0;
-  tab->gc_time = current_time();
-
   /* state change 2->0, 3->1 */
   tab->prune_state &= 1;
 
@@ -2540,16 +2878,212 @@ again:
 
   rt_prune_sources();
 
+  uint flushed_channels = 0;
+
   /* Close flushed channels */
   WALK_LIST2_DELSAFE(ih, n, x, tab->imports, n)
     if (ih->import_state == TIS_FLUSHING)
     {
-      rt_set_import_state(ih, TIS_CLEARED);
-      ih->stopped(ih->req);
-      rem_node(&ih->n);
-      mb_free(ih);
-      rt_unlock_table(tab);
+      ih->flush_seq = tab->exporter.next_seq;
+      rt_set_import_state(ih, TIS_WAITING);
+      flushed_channels++;
+    }
+    else if (ih->stale_pruning != ih->stale_pruned)
+    {
+      ih->stale_pruned = ih->stale_pruning;
+      if (ih->req->trace_routes & D_STATES)
+	log(L_TRACE "%s: table prune after refresh end [%u]", ih->req->name, ih->stale_pruned);
+    }
+
+  /* In some cases, we may want to directly proceed to export cleanup */
+  if (EMPTY_LIST(tab->exporter.hooks) && flushed_channels)
+    rt_export_cleanup(tab);
+}
+
+static void
+rt_export_cleanup(rtable *tab)
+{
+  tab->export_used = 0;
+
+  u64 min_seq = ~((u64) 0);
+  struct rt_pending_export *last_export_to_free = NULL;
+  struct rt_pending_export *first = tab->exporter.first;
+
+  struct rt_export_hook *eh;
+  node *n;
+  WALK_LIST2(eh, n, tab->exporter.hooks, n)
+  {
+    switch (atomic_load_explicit(&eh->export_state, memory_order_acquire))
+    {
+      case TES_DOWN:
+	continue;
+
+      case TES_READY:
+	{
+	  struct rt_pending_export *last = atomic_load_explicit(&eh->last_export, memory_order_acquire);
+	  if (!last)
+	    /* No last export means that the channel has exported nothing since last cleanup */
+	    goto done;
+
+	  else if (min_seq > last->seq)
+	  {
+	    min_seq = last->seq;
+	    last_export_to_free = last;
+	  }
+	  continue;
+	}
+
+      default:
+	/* It's only safe to cleanup when the export state is idle or regular. No feeding or stopping allowed. */
+	goto done;
+    }
+  }
+
+  tab->exporter.first = last_export_to_free ? rt_next_export_fast(last_export_to_free) : NULL;
+
+  if (config->table_debug)
+    log(L_TRACE "%s: Export cleanup, old exporter.first seq %lu, new %lu, min_seq %ld",
+      tab->name,
+      first ? first->seq : 0,
+      tab->exporter.first ? tab->exporter.first->seq : 0,
+      min_seq);
+
+  WALK_LIST2(eh, n, tab->exporter.hooks, n)
+  {
+    if (atomic_load_explicit(&eh->export_state, memory_order_acquire) != TES_READY)
+      continue;
+
+    struct rt_pending_export *last = atomic_load_explicit(&eh->last_export, memory_order_acquire);
+    if (last == last_export_to_free)
+    {
+      /* This may fail when the channel managed to export more inbetween. This is OK. */
+      atomic_compare_exchange_strong_explicit(
+	  &eh->last_export, &last, NULL,
+	  memory_order_release,
+	  memory_order_relaxed);
+
+      DBG("store hook=%p last_export=NULL\n", eh);
+    }
+  }
+
+  while (first && (first->seq <= min_seq))
+  {
+    ASSERT_DIE(first->new || first->old);
+
+    const net_addr *n = first->new ?
+      first->new->rte.net :
+      first->old->rte.net;
+    net *net = SKIP_BACK(struct network, n.addr, (net_addr (*)[0]) n);
+
+    ASSERT_DIE(net->first == first);
+    
+    if (first == net->last)
+      /* The only export here */
+      net->last = net->first = NULL;
+    else
+      /* First is now the next one */
+      net->first = atomic_load_explicit(&first->next, memory_order_relaxed);
+
+    /* For now, the old route may be finally freed */
+    if (first->old)
+    {
+      rt_rte_trace_in(D_ROUTES, first->old->rte.sender->req, &first->old->rte, "freed");
+      hmap_clear(&tab->id_map, first->old->rte.id);
+      rte_free(first->old);
     }
+
+#ifdef LOCAL_DEBUG
+    memset(first, 0xbd, sizeof(struct rt_pending_export));
+#endif
+
+    struct rt_export_block *reb = HEAD(tab->exporter.pending);
+    ASSERT_DIE(reb == PAGE_HEAD(first));
+
+    u32 pos = (first - &reb->export[0]);
+    u32 end = atomic_load_explicit(&reb->end, memory_order_relaxed);
+    ASSERT_DIE(pos < end);
+
+    struct rt_pending_export *next = NULL;
+    
+    if (++pos < end)
+      next = &reb->export[pos];
+    else
+    {
+      rem_node(&reb->n);
+
+#ifdef LOCAL_DEBUG
+      memset(reb, 0xbe, page_size);
+#endif
+
+      free_page(reb);
+
+      if (EMPTY_LIST(tab->exporter.pending))
+      {
+	if (config->table_debug)
+	  log(L_TRACE "%s: Resetting export seq", tab->name);
+
+	node *n;
+	WALK_LIST2(eh, n, tab->exporter.hooks, n)
+	{
+	  if (atomic_load_explicit(&eh->export_state, memory_order_acquire) != TES_READY)
+	    continue;
+
+	  ASSERT_DIE(atomic_load_explicit(&eh->last_export, memory_order_acquire) == NULL);
+	  bmap_reset(&eh->seq_map, 1024);
+	}
+
+	tab->exporter.next_seq = 1;
+      }
+      else
+      {
+	reb = HEAD(tab->exporter.pending);
+	next = &reb->export[0];
+      }
+    }
+
+    first = next;
+  }
+
+  rt_check_cork_low(tab);
+
+done:;
+  struct rt_import_hook *ih; node *x;
+  _Bool imports_stopped = 0;
+  WALK_LIST2_DELSAFE(ih, n, x, tab->imports, n)
+    if (ih->import_state == TIS_WAITING)
+      if (!first || (first->seq >= ih->flush_seq))
+      {
+	ih->import_state = TIS_CLEARED;
+	ih->stopped(ih->req);
+	rem_node(&ih->n);
+	mb_free(ih);
+	rt_unlock_table(tab);
+	imports_stopped = 1;
+      }
+
+  if (tab->export_used)
+    ev_schedule(tab->rt_event);
+
+  if (imports_stopped)
+  {
+    if (config->table_debug)
+      log(L_TRACE "%s: Sources pruning routine requested", tab->name);
+
+    rt_prune_sources();
+  }
+
+  if (EMPTY_LIST(tab->exporter.pending) && tm_active(tab->exporter.export_timer))
+    tm_stop(tab->exporter.export_timer);
+}
+
+static void
+rt_cork_release_hook(void *data UNUSED)
+{
+  do synchronize_rcu();
+  while (
+      !atomic_load_explicit(&rt_cork.active, memory_order_acquire) &&
+      ev_run_list(&rt_cork.queue)
+      );
 }
 
 /**
@@ -2627,6 +3161,20 @@ rt_preconfig(struct config *c)
   rt_new_table(cf_get_symbol("master6"), NET_IP6);
 }
 
+void
+rt_postconfig(struct config *c)
+{
+  uint num_tables = list_length(&c->tables);
+  btime def_gc_period = 400 MS * num_tables;
+  def_gc_period = MAX(def_gc_period, 10 S);
+  def_gc_period = MIN(def_gc_period, 600 S);
+
+  struct rtable_config *rc;
+  WALK_LIST(rc, c->tables)
+    if (rc->gc_period == (uint) -1)
+      rc->gc_period = (uint) def_gc_period;
+}
+
 
 /*
  * Some functions for handing internal next hop updates
@@ -3017,6 +3565,11 @@ rt_next_hop_update_net(rtable *tab, net *n)
 	/* Replace the route in the list */
 	new->next = e->next;
 	*k = e = new;
+
+	/* Get a new ID for the route */
+	new->rte.lastmod = current_time();
+	new->rte.id = hmap_first_zero(&tab->id_map);
+	hmap_set(&tab->id_map, new->rte.id);
       }
 
   ASSERT_DIE(pos <= count);
@@ -3043,14 +3596,14 @@ rt_next_hop_update_net(rtable *tab, net *n)
   for (int i=0; i<count; i++)
   {
     _Bool nb = (new == updates[i].new), ob = (old_best == updates[i].old);
-    const char *best_indicator[2][2] = { { "updated", "updated [-best]" }, { "updated [+best]", "updated [best]" } };
+    const char *best_indicator[2][2] = {
+      { "autoupdated", "autoupdated [-best]" },
+      { "autoupdated [+best]", "autoupdated [best]" }
+    };
     rt_rte_trace_in(D_ROUTES, updates[i].new->rte.sender->req, &updates[i].new->rte, best_indicator[nb][ob]);
     rte_announce_i(tab, n, updates[i].new, updates[i].old, new, old_best);
   }
 
-  for (int i=0; i<count; i++)
-    rte_free(updates[i].old);
-
   return count;
 }
 
@@ -3109,10 +3662,12 @@ rt_new_table(struct symbol *s, uint addr_type)
   cf_define_symbol(s, SYM_TABLE, table, c);
   c->name = s->name;
   c->addr_type = addr_type;
-  c->gc_max_ops = 1000;
-  c->gc_min_time = 5;
+  c->gc_threshold = 1000;
+  c->gc_period = (uint) -1;	/* set in rt_postconfig() */
   c->min_settle_time = 1 S;
   c->max_settle_time = 20 S;
+  c->cork_threshold.low = 128;
+  c->cork_threshold.high = 512;
 
   add_tail(&new_config->tables, &c->n);
 
@@ -3158,6 +3713,36 @@ rt_unlock_table(rtable *r)
     }
 }
 
+static void
+rt_check_cork_low(rtable *tab)
+{
+  if (!tab->cork_active)
+    return;
+
+  if (!tab->exporter.first || (tab->exporter.first->seq + tab->cork_threshold.low > tab->exporter.next_seq))
+  {
+    tab->cork_active = 0;
+    rt_cork_release();
+
+    if (config->table_debug)
+      log(L_TRACE "%s: Uncorked", tab->name);
+  }
+}
+
+static void
+rt_check_cork_high(rtable *tab)
+{
+  if (!tab->cork_active && tab->exporter.first && (tab->exporter.first->seq + tab->cork_threshold.high <= tab->exporter.next_seq))
+  {
+    tab->cork_active = 1;
+    rt_cork_acquire();
+
+    if (config->table_debug)
+      log(L_TRACE "%s: Corked", tab->name);
+  }
+}
+
+
 static int
 rt_reconfigure(rtable *tab, struct rtable_config *new, struct rtable_config *old)
 {
@@ -3171,6 +3756,14 @@ rt_reconfigure(rtable *tab, struct rtable_config *new, struct rtable_config *old
   tab->name = new->name;
   tab->config = new;
 
+  tab->cork_threshold = new->cork_threshold;
+
+  if (new->cork_threshold.high != old->cork_threshold.high)
+    rt_check_cork_high(tab);
+
+  if (new->cork_threshold.low != old->cork_threshold.low)
+    rt_check_cork_low(tab);
+
   return 1;
 }
 
@@ -3229,6 +3822,16 @@ rt_commit(struct config *new, struct config *old)
   DBG("\tdone\n");
 }
 
+static void
+rt_feed_done(struct rt_export_hook *c)
+{
+  c->event->hook = rt_export_hook;
+
+  rt_set_export_state(c, TES_READY);
+
+  rt_send_export_event(c);
+}
+
 /**
  * rt_feed_by_fib - advertise all routes to a channel by walking a fib
  * @c: channel to be fed
@@ -3246,7 +3849,7 @@ rt_feed_by_fib(void *data)
   struct fib_iterator *fit = &c->feed_fit;
   int max_feed = 256;
 
-  ASSERT(c->export_state == TES_FEEDING);
+  ASSERT(atomic_load_explicit(&c->export_state, memory_order_relaxed) == TES_FEEDING);
 
   rtable *tab = SKIP_BACK(rtable, exporter, c->table);
 
@@ -3255,18 +3858,19 @@ rt_feed_by_fib(void *data)
       if (max_feed <= 0)
 	{
 	  FIB_ITERATE_PUT(fit);
-	  ev_schedule_work(c->event);
+	  rt_send_export_event(c);
 	  return;
 	}
 
-      ASSERT(c->export_state == TES_FEEDING);
+      if (atomic_load_explicit(&c->export_state, memory_order_acquire) != TES_FEEDING)
+	return;
 
       if ((c->req->addr_mode == TE_ADDR_NONE) || net_in_netX(n->n.addr, c->req->addr))
 	max_feed -= rt_feed_net(c, n);
     }
   FIB_ITERATE_END;
 
-  rt_set_export_state(c, TES_READY);
+  rt_feed_done(c);
 }
 
 static void
@@ -3280,7 +3884,7 @@ rt_feed_by_trie(void *data)
 
   int max_feed = 256;
 
-  ASSERT_DIE(c->export_state == TES_FEEDING);
+  ASSERT(atomic_load_explicit(&c->export_state, memory_order_relaxed) == TES_FEEDING);
 
   net_addr addr;
   while (trie_walk_next(ws, &addr))
@@ -3292,7 +3896,8 @@ rt_feed_by_trie(void *data)
     if ((max_feed -= rt_feed_net(c, n)) <= 0)
       return;
 
-    ASSERT_DIE(c->export_state == TES_FEEDING);
+    if (atomic_load_explicit(&c->export_state, memory_order_acquire) != TES_FEEDING)
+      return;
   }
 
   rt_unlock_trie(tab, c->walk_lock);
@@ -3301,7 +3906,7 @@ rt_feed_by_trie(void *data)
   mb_free(c->walk_state);
   c->walk_state = NULL;
 
-  rt_set_export_state(c, TES_READY);
+  rt_feed_done(c);
 }
 
 static void
@@ -3310,14 +3915,14 @@ rt_feed_equal(void *data)
   struct rt_export_hook *c = data;
   rtable *tab = SKIP_BACK(rtable, exporter, c->table);
 
-  ASSERT_DIE(c->export_state == TES_FEEDING);
+  ASSERT_DIE(atomic_load_explicit(&c->export_state, memory_order_relaxed) == TES_FEEDING);
   ASSERT_DIE(c->req->addr_mode == TE_ADDR_EQUAL);
 
   net *n = net_find(tab, c->req->addr);
   if (n)
     rt_feed_net(c, n);
 
-  rt_set_export_state(c, TES_READY);
+  rt_feed_done(c);
 }
 
 static void
@@ -3326,52 +3931,53 @@ rt_feed_for(void *data)
   struct rt_export_hook *c = data;
   rtable *tab = SKIP_BACK(rtable, exporter, c->table);
 
-  ASSERT_DIE(c->export_state == TES_FEEDING);
+  ASSERT_DIE(atomic_load_explicit(&c->export_state, memory_order_relaxed) == TES_FEEDING);
   ASSERT_DIE(c->req->addr_mode == TE_ADDR_FOR);
 
   net *n = net_route(tab, c->req->addr);
   if (n)
     rt_feed_net(c, n);
 
-  rt_set_export_state(c, TES_READY);
+  rt_feed_done(c);
 }
 
 static uint
 rt_feed_net(struct rt_export_hook *c, net *n)
 {
-      if (c->req->export_bulk)
-      {
-	uint count = rte_feed_count(n);
-	if (count)
-	{
-	  rte_update_lock();
-	  rte **feed = alloca(count * sizeof(rte *));
-	  rte_feed_obtain(n, feed, count);
-	  struct rt_pending_export rpe = { .new_best = n->routes };
-	  c->req->export_bulk(c->req, n->n.addr, &rpe, feed, count);
-	  rte_update_unlock();
-	}
-	return count;
-      }
+  uint count = 0;
 
-      if (n->routes && rte_is_valid(&n->routes->rte))
-      {
-	rte_update_lock();
-	struct rt_pending_export rpe = { .new = n->routes, .new_best = n->routes };
-	c->req->export_one(c->req, n->n.addr, &rpe);
-	rte_update_unlock();
-	return 1;
-      }
+  if (c->req->export_bulk)
+  {
+    count = rte_feed_count(n);
+    if (count)
+    {
+      rte_update_lock();
+      rte **feed = alloca(count * sizeof(rte *));
+      rte_feed_obtain(n, feed, count);
+      c->req->export_bulk(c->req, n->n.addr, NULL, feed, count);
+      rte_update_unlock();
+    }
+  }
 
-      return 0;
-}
+  else if (n->routes)
+  {
+    rte_update_lock();
+    struct rt_pending_export rpe = { .new = n->routes, .new_best = n->routes };
+    c->req->export_one(c->req, n->n.addr, &rpe);
+    rte_update_unlock();
+    count = 1;
+  }
 
+  for (struct rt_pending_export *rpe = n->first; rpe; rpe = rpe_next(rpe, NULL))
+    rpe_mark_seen(c, rpe);
+
+  return count;
+}
 
 /*
  *	Import table
  */
 
-
 void channel_reload_export_bulk(struct rt_export_request *req, const net_addr *net, struct rt_pending_export *rpe UNUSED, rte **feed, uint count)
 {
   struct channel *c = SKIP_BACK(struct channel, reload_req, req);
@@ -3589,9 +4195,12 @@ rt_update_hostentry(rtable *tab, struct hostentry *he)
     {
       struct rte_storage *e = n->routes;
       ea_list *a = e->rte.attrs;
-      pxlen = n->n.addr->pxlen;
+      u32 pref = rt_get_preference(&e->rte);
 
-      if (ea_find(a, &ea_gen_hostentry))
+      for (struct rte_storage *ee = n->routes; ee; ee = ee->next)
+	if (rte_is_valid(&ee->rte) &&
+	    (rt_get_preference(&ee->rte) >= pref) &&
+	    ea_find(ee->rte.attrs, &ea_gen_hostentry))
 	{
 	  /* Recursive route should not depend on another recursive route */
 	  log(L_WARN "Next hop address %I resolvable through recursive route for %N",
@@ -3599,6 +4208,8 @@ rt_update_hostentry(rtable *tab, struct hostentry *he)
 	  goto done;
 	}
 
+      pxlen = n->n.addr->pxlen;
+
       eattr *nhea = ea_find(a, &ea_gen_nexthop);
       ASSERT_DIE(nhea);
       struct nexthop_adata *nhad = (void *) nhea->u.ptr;
diff --git a/nest/rt.h b/nest/rt.h
index 5a8c5a19..66111dde 100644
--- a/nest/rt.h
+++ b/nest/rt.h
@@ -17,6 +17,10 @@
 #include "lib/type.h"
 #include "lib/fib.h"
 #include "lib/route.h"
+#include "lib/event.h"
+#include "lib/rcu.h"
+
+#include <stdatomic.h>
 
 struct ea_list;
 struct protocol;
@@ -30,6 +34,10 @@ struct f_trie;
 struct f_trie_walk_state;
 struct cli;
 
+struct rt_cork_threshold {
+  u64 low, high;
+};
+
 /*
  *	Master Routing Tables. Generally speaking, each of them contains a FIB
  *	with each entry pointing to a list of route entries representing routes
@@ -47,13 +55,14 @@ struct rtable_config {
   struct rtable *table;
   struct proto_config *krt_attached;	/* Kernel syncer attached to this table */
   uint addr_type;			/* Type of address data stored in table (NET_*) */
-  int gc_max_ops;			/* Maximum number of operations before GC is run */
-  int gc_min_time;			/* Minimum time between two consecutive GC runs */
+  uint gc_threshold;			/* Maximum number of operations before GC is run */
+  uint gc_period;			/* Approximate time between two consecutive GC runs */
   byte sorted;				/* Routes of network are sorted according to rte_better() */
-  byte internal;			/* Internal table of a protocol */
   byte trie_used;			/* Rtable has attached trie */
   btime min_settle_time;		/* Minimum settle time for notifications */
   btime max_settle_time;		/* Maximum settle time for notifications */
+  btime export_settle_time;		/* Delay before exports are announced */
+  struct rt_cork_threshold cork_threshold;	/* Cork threshold values */
 };
 
 struct rt_export_hook;
@@ -62,9 +71,17 @@ struct rt_export_request;
 struct rt_exporter {
   list hooks;				/* Registered route export hooks */
   uint addr_type;			/* Type of address data exported (NET_*) */
+
   struct rt_export_hook *(*start)(struct rt_exporter *, struct rt_export_request *);
   void (*stop)(struct rt_export_hook *);
   void (*done)(struct rt_export_hook *);
+  void (*used)(struct rt_exporter *);
+
+  list pending;				/* List of packed struct rt_pending_export */
+  struct timer *export_timer;
+
+  struct rt_pending_export *first;	/* First export to announce */
+  u64 next_seq;				/* The next export will have this ID */
 };
 
 typedef struct rtable {
@@ -90,15 +107,21 @@ typedef struct rtable {
 					 * obstacle from this routing table.
 					 */
   struct event *rt_event;		/* Routing table event */
+  struct event *uncork_event;		/* Called when uncork happens */
+  struct timer *prune_timer;		/* Timer for periodic pruning / GC */
   btime last_rt_change;			/* Last time when route changed */
   btime base_settle_time;		/* Start time of rtable settling interval */
   btime gc_time;			/* Time of last GC */
-  int gc_counter;			/* Number of operations since last GC */
+  uint gc_counter;			/* Number of operations since last GC */
   byte prune_state;			/* Table prune state, 1 -> scheduled, 2-> running */
   byte prune_trie;			/* Prune prefix trie during next table prune */
   byte hcu_scheduled;			/* Hostcache update is scheduled */
+  byte hcu_corked;			/* Hostcache update is corked with this state */
   byte nhu_state;			/* Next Hop Update state */
-  byte internal;			/* This table is internal for some other object */
+  byte nhu_corked;			/* Next Hop Update is corked with this state */
+  byte export_used;			/* Pending Export pruning is scheduled */
+  byte cork_active;			/* Cork has been activated */
+  struct rt_cork_threshold cork_threshold;	/* Threshold for table cork */
   struct fib_iterator prune_fit;	/* Rtable prune FIB iterator */
   struct fib_iterator nhu_fit;		/* Next Hop Update FIB iterator */
   struct f_trie *trie_new;		/* New prefix trie defined during pruning */
@@ -127,13 +150,48 @@ struct rt_flowspec_link {
   u32 uc;
 };
 
+extern struct rt_cork {
+  _Atomic uint active;
+  event_list queue;
+  event run;
+} rt_cork;
+
+static inline void rt_cork_acquire(void)
+{
+  atomic_fetch_add_explicit(&rt_cork.active, 1, memory_order_acq_rel);
+}
+
+static inline void rt_cork_release(void)
+{
+  if (atomic_fetch_sub_explicit(&rt_cork.active, 1, memory_order_acq_rel) == 1)
+  {
+    synchronize_rcu();
+    ev_schedule_work(&rt_cork.run);
+  }
+}
+
+static inline int rt_cork_check(event *e)
+{
+  rcu_read_lock();
+
+  int corked = (atomic_load_explicit(&rt_cork.active, memory_order_acquire) > 0);
+  if (corked)
+    ev_send(&rt_cork.queue, e);
+
+  rcu_read_unlock();
+
+  return corked;
+}
+
+
 #define NHU_CLEAN	0
 #define NHU_SCHEDULED	1
 #define NHU_RUNNING	2
 #define NHU_DIRTY	3
 
 typedef struct network {
-  struct rte_storage *routes;			/* Available routes for this network */
+  struct rte_storage *routes;		/* Available routes for this network */
+  struct rt_pending_export *first, *last;
   struct fib_node n;			/* FIB flags reserved for kernel syncer */
 } net;
 
@@ -168,8 +226,10 @@ struct rte_storage {
   struct rte rte;			/* Route data */
 };
 
-#define RTE_COPY(r, l) ((r) ? (((*(l)) = (r)->rte), (l)) : NULL)
-#define RTE_OR_NULL(r) ((r) ? &((r)->rte) : NULL)
+#define RTE_COPY(r)		((r) ? (r)->rte : (rte) {})
+#define RTE_COPY_VALID(r)	(((r) && (rte_is_valid(&(r)->rte))) ? (r)->rte : (rte) {})
+#define RTE_OR_NULL(r)		((r) ? &((r)->rte) : NULL)
+#define RTE_VALID_OR_NULL(r)	(((r) && (rte_is_valid(&(r)->rte))) ? &((r)->rte) : NULL)
 
 /* Table-channel connections */
 
@@ -183,7 +243,6 @@ struct rt_import_request {
   /* Preimport is called when the @new route is just-to-be inserted, replacing @old.
    * Return a route (may be different or modified in-place) to continue or NULL to withdraw. */
   int (*preimport)(struct rt_import_request *req, struct rte *new, struct rte *old);
-  struct rte *(*rte_modify)(struct rte *, struct linpool *);
 };
 
 struct rt_import_hook {
@@ -200,15 +259,22 @@ struct rt_import_hook {
     u32 withdraws_accepted;		/* Number of route withdraws accepted and processed */
   } stats;
 
+  u64 flush_seq;			/* Table export seq when the channel announced flushing */
   btime last_state_change;		/* Time of last state transition */
 
   u8 import_state;			/* IS_* */
+  u8 stale_set;				/* Set this stale_cycle to imported routes */
+  u8 stale_valid;			/* Routes with this stale_cycle and bigger are considered valid */
+  u8 stale_pruned;			/* Last prune finished when this value was set at stale_valid */
+  u8 stale_pruning;			/* Last prune started when this value was set at stale_valid */
 
   void (*stopped)(struct rt_import_request *);	/* Stored callback when import is stopped */
 };
 
 struct rt_pending_export {
+  struct rt_pending_export * _Atomic next;	/* Next export for the same destination */
   struct rte_storage *new, *new_best, *old, *old_best;
+  u64 seq;				/* Sequential ID (table-local) of the pending export */
 };
 
 struct rt_export_request {
@@ -218,6 +284,8 @@ struct rt_export_request {
   u8 trace_routes;
   u8 addr_mode;				/* Network prefilter mode (TE_ADDR_*) */
 
+  event_list *list;			/* Where to schedule export events */
+
   /* There are two methods of export. You can either request feeding every single change
    * or feeding the whole route feed. In case of regular export, &export_one is preferred.
    * Anyway, when feeding, &export_bulk is preferred, falling back to &export_one.
@@ -237,7 +305,6 @@ struct rt_export_hook {
   struct rt_exporter *table;		/* The connected table */
 
   pool *pool;
-  linpool *lp;
 
   struct rt_export_request *req;	/* The requestor */
 
@@ -256,10 +323,15 @@ struct rt_export_hook {
     u32 hash_iter;				/* Iterator over hash */
   };
 
+  struct bmap seq_map;			/* Keep track which exports were already procesed */
+
+  struct rt_pending_export * _Atomic last_export;/* Last export processed */
+  struct rt_pending_export *rpe_next;	/* Next pending export to process */
+
   btime last_state_change;		/* Time of last state transition */
 
   u8 refeed_pending;			/* Refeeding and another refeed is scheduled */
-  u8 export_state;			/* Route export state (TES_*, see below) */
+  _Atomic u8 export_state;		/* Route export state (TES_*, see below) */
   u8 feed_type;				/* Which feeding method is used (TFT_*, see below) */
 
   struct event *event;			/* Event running all the export operations */
@@ -310,6 +382,15 @@ void rt_set_export_state(struct rt_export_hook *hook, u8 state);
 
 void rte_import(struct rt_import_request *req, const net_addr *net, rte *new, struct rte_src *src);
 
+/* Get next rpe. If src is given, it must match. */
+struct rt_pending_export *rpe_next(struct rt_pending_export *rpe, struct rte_src *src);
+
+/* Mark the pending export processed */
+void rpe_mark_seen(struct rt_export_hook *hook, struct rt_pending_export *rpe);
+
+/* Get pending export seen status */
+int rpe_get_seen(struct rt_export_hook *hook, struct rt_pending_export *rpe);
+
 /* Types of route announcement, also used as flags */
 #define RA_UNDEF	0		/* Undefined RA type */
 #define RA_OPTIMAL	1		/* Announcement of optimal route change */
@@ -363,6 +444,7 @@ struct config;
 
 void rt_init(void);
 void rt_preconfig(struct config *);
+void rt_postconfig(struct config *);
 void rt_commit(struct config *new, struct config *old);
 void rt_lock_table(rtable *);
 void rt_unlock_table(rtable *);
@@ -383,8 +465,8 @@ net *net_get(rtable *tab, const net_addr *addr);
 net *net_route(rtable *tab, const net_addr *n);
 int rt_examine(rtable *t, net_addr *a, struct channel *c, const struct filter *filter);
 rte *rt_export_merged(struct channel *c, rte ** feed, uint count, linpool *pool, int silent);
-void rt_refresh_begin(rtable *t, struct rt_import_request *);
-void rt_refresh_end(rtable *t, struct rt_import_request *);
+void rt_refresh_begin(struct rt_import_request *);
+void rt_refresh_end(struct rt_import_request *);
 void rt_modify_stale(rtable *t, struct rt_import_request *);
 void rt_schedule_prune(rtable *t);
 void rte_dump(struct rte_storage *);
diff --git a/proto/babel/babel.c b/proto/babel/babel.c
index 4939619f..00b9aa79 100644
--- a/proto/babel/babel.c
+++ b/proto/babel/babel.c
@@ -315,7 +315,9 @@ babel_add_seqno_request(struct babel_proto *p, struct babel_entry *e,
 
       /* Found older */
       rem_node(NODE sr);
-      rem_node(&sr->nbr_node);
+
+      if (sr->nbr)
+        rem_node(&sr->nbr_node);
 
       goto found;
     }
@@ -455,10 +457,7 @@ babel_flush_neighbor(struct babel_proto *p, struct babel_neighbor *nbr)
 
   struct babel_seqno_request *sr;
   WALK_LIST_FIRST2(sr, nbr_node, nbr->requests)
-  {
-    sr->nbr = NULL;
-    rem_node(&sr->nbr_node);
-  }
+    babel_remove_seqno_request(p, sr);
 
   nbr->ifa = NULL;
   rem_node(NODE nbr);
@@ -2258,9 +2257,9 @@ babel_kick_timer(struct babel_proto *p)
 
 
 static int
-babel_preexport(struct channel *c, struct rte *new)
+babel_preexport(struct channel *C, struct rte *new)
 {
-  if (new->src->proto != c->proto)
+  if (new->src->proto != C->proto)
     return 0;
 
   /* Reject our own unreachable routes */
diff --git a/proto/bfd/Makefile b/proto/bfd/Makefile
index dbdc0a09..11d639d7 100644
--- a/proto/bfd/Makefile
+++ b/proto/bfd/Makefile
@@ -1,4 +1,4 @@
-src := bfd.c io.c packets.c
+src := bfd.c packets.c
 obj := $(src-o-files)
 $(all-daemon)
 $(cf-local)
diff --git a/proto/bfd/bfd.c b/proto/bfd/bfd.c
index 871ecf69..e7d27f74 100644
--- a/proto/bfd/bfd.c
+++ b/proto/bfd/bfd.c
@@ -113,8 +113,16 @@
 #define HASH_IP_EQ(a1,n1,a2,n2)	ipa_equal(a1, a2) && n1 == n2
 #define HASH_IP_FN(a,n)		ipa_hash(a) ^ u32_hash(n)
 
-static list STATIC_LIST_INIT(bfd_proto_list);
-static list STATIC_LIST_INIT(bfd_wait_list);
+DEFINE_DOMAIN(rtable);
+#define BFD_LOCK	LOCK_DOMAIN(rtable, bfd_global.lock)
+#define BFD_UNLOCK	UNLOCK_DOMAIN(rtable, bfd_global.lock)
+
+static struct {
+  DOMAIN(rtable) lock;
+  list wait_list;
+  list pickup_list;
+  list proto_list;
+} bfd_global;
 
 const char *bfd_state_names[] = { "AdminDown", "Down", "Init", "Up" };
 
@@ -188,7 +196,7 @@ bfd_session_update_tx_interval(struct bfd_session *s)
     return;
 
   /* Set timer relative to last tx_timer event */
-  tm_set(s->tx_timer, s->last_tx + tx_int_l);
+  tm_set_in(s->tx_timer, s->last_tx + tx_int_l, s->ifa->bfd->p.loop);
 }
 
 static void
@@ -202,7 +210,7 @@ bfd_session_update_detection_time(struct bfd_session *s, int kick)
   if (!s->last_rx)
     return;
 
-  tm_set(s->hold_timer, s->last_rx + timeout);
+  tm_set_in(s->hold_timer, s->last_rx + timeout, s->ifa->bfd->p.loop);
 }
 
 static void
@@ -226,7 +234,7 @@ bfd_session_control_tx_timer(struct bfd_session *s, int reset)
   if (reset || !tm_active(s->tx_timer))
   {
     s->last_tx = 0;
-    tm_start(s->tx_timer, 0);
+    tm_start_in(s->tx_timer, 0, s->ifa->bfd->p.loop);
   }
 
   return;
@@ -419,7 +427,7 @@ bfd_get_free_id(struct bfd_proto *p)
 static struct bfd_session *
 bfd_add_session(struct bfd_proto *p, ip_addr addr, ip_addr local, struct iface *iface, struct bfd_options *opts)
 {
-  birdloop_enter(p->loop);
+  ASSERT_DIE(birdloop_inside(p->p.loop));
 
   struct bfd_iface *ifa = bfd_get_iface(p, local, iface);
 
@@ -454,8 +462,6 @@ bfd_add_session(struct bfd_proto *p, ip_addr addr, ip_addr local, struct iface *
 
   TRACE(D_EVENTS, "Session to %I added", s->addr);
 
-  birdloop_leave(p->loop);
-
   return s;
 }
 
@@ -463,38 +469,34 @@ bfd_add_session(struct bfd_proto *p, ip_addr addr, ip_addr local, struct iface *
 static void
 bfd_open_session(struct bfd_proto *p, struct bfd_session *s, ip_addr local, struct iface *ifa)
 {
-  birdloop_enter(p->loop);
+  birdloop_enter(p->p.loop);
 
   s->opened = 1;
 
   bfd_session_control_tx_timer(s);
 
-  birdloop_leave(p->loop);
+  birdloop_leave(p->p.loop);
 }
 
 static void
 bfd_close_session(struct bfd_proto *p, struct bfd_session *s)
 {
-  birdloop_enter(p->loop);
+  birdloop_enter(p->p.loop);
 
   s->opened = 0;
 
   bfd_session_update_state(s, BFD_STATE_DOWN, BFD_DIAG_PATH_DOWN);
   bfd_session_control_tx_timer(s);
 
-  birdloop_leave(p->loop);
+  birdloop_leave(p->p.loop);
 }
 */
 
 static void
-bfd_remove_session(struct bfd_proto *p, struct bfd_session *s)
+bfd_remove_session_locked(struct bfd_proto *p, struct bfd_session *s)
 {
-  ip_addr ip = s->addr;
-
   /* Caller should ensure that request list is empty */
 
-  birdloop_enter(p->loop);
-
   /* Remove session from notify list if scheduled for notification */
   /* No need for bfd_lock_sessions(), we are already protected by birdloop_enter() */
   if (NODE_VALID(&s->n))
@@ -508,11 +510,17 @@ bfd_remove_session(struct bfd_proto *p, struct bfd_session *s)
   HASH_REMOVE(p->session_hash_id, HASH_ID, s);
   HASH_REMOVE(p->session_hash_ip, HASH_IP, s);
 
-  sl_free(s);
+  TRACE(D_EVENTS, "Session to %I removed", s->addr);
 
-  TRACE(D_EVENTS, "Session to %I removed", ip);
+  sl_free(s);
+}
 
-  birdloop_leave(p->loop);
+static void
+bfd_remove_session(struct bfd_proto *p, struct bfd_session *s)
+{
+  birdloop_enter(p->p.loop);
+  bfd_remove_session_locked(p, s);
+  birdloop_leave(p->p.loop);
 }
 
 static void
@@ -521,7 +529,7 @@ bfd_reconfigure_session(struct bfd_proto *p, struct bfd_session *s)
   if (EMPTY_LIST(s->request_list))
     return;
 
-  birdloop_enter(p->loop);
+  birdloop_enter(p->p.loop);
 
   struct bfd_request *req = SKIP_BACK(struct bfd_request, n, HEAD(s->request_list));
   s->cf = bfd_merge_options(s->ifa->cf, &req->opts);
@@ -534,7 +542,7 @@ bfd_reconfigure_session(struct bfd_proto *p, struct bfd_session *s)
 
   bfd_session_control_tx_timer(s, 0);
 
-  birdloop_leave(p->loop);
+  birdloop_leave(p->p.loop);
 
   TRACE(D_EVENTS, "Session to %I reconfigured", s->addr);
 }
@@ -627,9 +635,9 @@ bfd_reconfigure_iface(struct bfd_proto *p, struct bfd_iface *ifa, struct bfd_con
     (new->passive != old->passive);
 
   /* This should be probably changed to not access ifa->cf from the BFD thread */
-  birdloop_enter(p->loop);
+  birdloop_enter(p->p.loop);
   ifa->cf = new;
-  birdloop_leave(p->loop);
+  birdloop_leave(p->p.loop);
 }
 
 
@@ -690,41 +698,68 @@ bfd_add_request(struct bfd_proto *p, struct bfd_request *req)
 }
 
 static void
-bfd_submit_request(struct bfd_request *req)
+bfd_pickup_requests(void *_data UNUSED)
 {
   node *n;
+  WALK_LIST(n, bfd_global.proto_list)
+  {
+    struct bfd_proto *p = SKIP_BACK(struct bfd_proto, bfd_node, n);
+    birdloop_enter(p->p.loop);
+    BFD_LOCK;
 
-  WALK_LIST(n, bfd_proto_list)
-    if (bfd_add_request(SKIP_BACK(struct bfd_proto, bfd_node, n), req))
-      return;
+    node *rn, *rnxt;
+    WALK_LIST_DELSAFE(rn, rnxt, bfd_global.pickup_list)
+      bfd_add_request(p, SKIP_BACK(struct bfd_request, n, rn));
 
-  rem_node(&req->n);
-  add_tail(&bfd_wait_list, &req->n);
-  req->session = NULL;
-  bfd_request_notify(req, BFD_STATE_ADMIN_DOWN, 0);
+    BFD_UNLOCK;
+    birdloop_leave(p->p.loop);
+  }
+
+  BFD_LOCK;
+  node *rn, *rnxt;
+  WALK_LIST_DELSAFE(rn, rnxt, bfd_global.pickup_list)
+  {
+    rem_node(rn);
+    add_tail(&bfd_global.wait_list, rn);
+    bfd_request_notify(SKIP_BACK(struct bfd_request, n, rn), BFD_STATE_ADMIN_DOWN, 0);
+  }
+  BFD_UNLOCK;
 }
 
+static event bfd_pickup_event = { .hook = bfd_pickup_requests };
+
 static void
 bfd_take_requests(struct bfd_proto *p)
 {
   node *n, *nn;
-
-  WALK_LIST_DELSAFE(n, nn, bfd_wait_list)
+  BFD_LOCK;
+  WALK_LIST_DELSAFE(n, nn, bfd_global.wait_list)
     bfd_add_request(p, SKIP_BACK(struct bfd_request, n, n));
+  BFD_UNLOCK;
 }
 
 static void
 bfd_drop_requests(struct bfd_proto *p)
 {
   node *n;
-
-  HASH_WALK(p->session_hash_id, next_id, s)
+  BFD_LOCK;
+  HASH_WALK_DELSAFE(p->session_hash_id, next_id, s)
   {
-    /* We assume that p is not in bfd_proto_list */
     WALK_LIST_FIRST(n, s->request_list)
-      bfd_submit_request(SKIP_BACK(struct bfd_request, n, n));
+    {
+      struct bfd_request *req = SKIP_BACK(struct bfd_request, n, n);
+      rem_node(&req->n);
+      add_tail(&bfd_global.pickup_list, &req->n);
+      req->session = NULL;
+      bfd_request_notify(req, BFD_STATE_ADMIN_DOWN, 0);
+    }
+
+    ev_send(&global_event_list, &bfd_pickup_event);
+
+    bfd_remove_session_locked(p, s);
   }
   HASH_WALK_END;
+  BFD_UNLOCK;
 }
 
 static struct resclass bfd_request_class;
@@ -737,9 +772,6 @@ bfd_request_session(pool *p, ip_addr addr, ip_addr local,
 {
   struct bfd_request *req = ralloc(p, &bfd_request_class);
 
-  /* Hack: self-link req->n, we will call rem_node() on it */
-  req->n.prev = req->n.next = &req->n;
-
   req->addr = addr;
   req->local = local;
   req->iface = iface;
@@ -748,11 +780,16 @@ bfd_request_session(pool *p, ip_addr addr, ip_addr local,
   if (opts)
     req->opts = *opts;
 
-  bfd_submit_request(req);
-
   req->hook = hook;
   req->data = data;
 
+  req->session = NULL;
+
+  BFD_LOCK;
+  add_tail(&bfd_global.pickup_list, &req->n);
+  ev_send(&global_event_list, &bfd_pickup_event);
+  BFD_UNLOCK;
+
   return req;
 }
 
@@ -1023,10 +1060,10 @@ bfd_start(struct proto *P)
   struct bfd_proto *p = (struct bfd_proto *) P;
   struct bfd_config *cf = (struct bfd_config *) (P->cf);
 
-  p->loop = birdloop_new();
-  p->tpool = rp_new(NULL, "BFD thread root");
   pthread_spin_init(&p->lock, PTHREAD_PROCESS_PRIVATE);
 
+  p->tpool = rp_new(P->pool, "BFD loop pool");
+
   p->session_slab = sl_new(P->pool, sizeof(struct bfd_session));
   HASH_INIT(p->session_hash_id, P->pool, 8);
   HASH_INIT(p->session_hash_ip, P->pool, 8);
@@ -1036,9 +1073,7 @@ bfd_start(struct proto *P)
   init_list(&p->notify_list);
   bfd_notify_init(p);
 
-  add_tail(&bfd_proto_list, &p->bfd_node);
-
-  birdloop_enter(p->loop);
+  add_tail(&bfd_global.proto_list, &p->bfd_node);
 
   if (!cf->strict_bind)
   {
@@ -1055,42 +1090,33 @@ bfd_start(struct proto *P)
       p->rx6_m = bfd_open_rx_sk(p, 1, SK_IPV6);
   }
 
-  birdloop_leave(p->loop);
-
   bfd_take_requests(p);
 
   struct bfd_neighbor *n;
   WALK_LIST(n, cf->neigh_list)
     bfd_start_neighbor(p, n);
 
-  birdloop_start(p->loop);
-
   return PS_UP;
 }
 
-
 static int
 bfd_shutdown(struct proto *P)
 {
   struct bfd_proto *p = (struct bfd_proto *) P;
-  struct bfd_config *cf = (struct bfd_config *) (P->cf);
+  struct bfd_config *cf = (struct bfd_config *) (p->p.cf);
 
   rem_node(&p->bfd_node);
 
-  birdloop_stop(p->loop);
-
-  struct bfd_neighbor *n;
-  WALK_LIST(n, cf->neigh_list)
-    bfd_stop_neighbor(p, n);
+  struct bfd_neighbor *bn;
+  WALK_LIST(bn, cf->neigh_list)
+    bfd_stop_neighbor(p, bn);
 
   bfd_drop_requests(p);
 
-  /* FIXME: This is hack */
-  birdloop_enter(p->loop);
-  rfree(p->tpool);
-  birdloop_leave(p->loop);
-
-  birdloop_free(p->loop);
+  if (p->rx4_1) sk_stop(p->rx4_1);
+  if (p->rx4_m) sk_stop(p->rx4_m);
+  if (p->rx6_1) sk_stop(p->rx6_1);
+  if (p->rx6_m) sk_stop(p->rx6_m);
 
   return PS_DOWN;
 }
@@ -1111,7 +1137,7 @@ bfd_reconfigure(struct proto *P, struct proto_config *c)
       (new->strict_bind != old->strict_bind))
     return 0;
 
-  birdloop_mask_wakeups(p->loop);
+  birdloop_mask_wakeups(p->p.loop);
 
   WALK_LIST(ifa, p->iface_list)
     bfd_reconfigure_iface(p, ifa, new);
@@ -1125,7 +1151,7 @@ bfd_reconfigure(struct proto *P, struct proto_config *c)
 
   bfd_reconfigure_neighbors(p, new);
 
-  birdloop_unmask_wakeups(p->loop);
+  birdloop_unmask_wakeups(p->p.loop);
 
   return 1;
 }
@@ -1196,4 +1222,9 @@ void
 bfd_build(void)
 {
   proto_build(&proto_bfd);
+
+  bfd_global.lock = DOMAIN_NEW(rtable, "BFD Global");
+  init_list(&bfd_global.wait_list);
+  init_list(&bfd_global.pickup_list);
+  init_list(&bfd_global.proto_list);
 }
diff --git a/proto/bfd/bfd.h b/proto/bfd/bfd.h
index 60b7916c..b9afaf92 100644
--- a/proto/bfd/bfd.h
+++ b/proto/bfd/bfd.h
@@ -17,12 +17,12 @@
 #include "nest/password.h"
 #include "conf/conf.h"
 #include "lib/hash.h"
+#include "lib/io-loop.h"
 #include "lib/resource.h"
 #include "lib/socket.h"
 #include "lib/string.h"
 
 #include "nest/bfd.h"
-#include "io.h"
 
 
 #define BFD_CONTROL_PORT	3784
@@ -88,9 +88,11 @@ struct bfd_neighbor
 struct bfd_proto
 {
   struct proto p;
-  struct birdloop *loop;
-  pool *tpool;
+
   pthread_spinlock_t lock;
+
+  pool *tpool;
+
   node bfd_node;
 
   slab *session_slab;
diff --git a/proto/bfd/config.Y b/proto/bfd/config.Y
index 70461872..0d6e33fa 100644
--- a/proto/bfd/config.Y
+++ b/proto/bfd/config.Y
@@ -37,6 +37,7 @@ proto: bfd_proto ;
 bfd_proto_start: proto_start BFD
 {
   this_proto = proto_config_new(&proto_bfd, $1);
+  this_proto->loop_order = DOMAIN_ORDER(proto);
   init_list(&BFD_CFG->patt_list);
   init_list(&BFD_CFG->neigh_list);
   BFD_CFG->accept_ipv4 = BFD_CFG->accept_ipv6 = 1;
diff --git a/proto/bfd/io.h b/proto/bfd/io.h
deleted file mode 100644
index ec706e9a..00000000
--- a/proto/bfd/io.h
+++ /dev/null
@@ -1,34 +0,0 @@
-/*
- *	BIRD -- I/O and event loop
- *
- *	Can be freely distributed and used under the terms of the GNU GPL.
- */
-
-#ifndef _BIRD_BFD_IO_H_
-#define _BIRD_BFD_IO_H_
-
-#include "nest/bird.h"
-#include "lib/lists.h"
-#include "lib/resource.h"
-#include "lib/event.h"
-#include "lib/timer.h"
-#include "lib/socket.h"
-
-
-void ev2_schedule(event *e);
-
-void sk_start(sock *s);
-void sk_stop(sock *s);
-
-struct birdloop *birdloop_new(void);
-void birdloop_start(struct birdloop *loop);
-void birdloop_stop(struct birdloop *loop);
-void birdloop_free(struct birdloop *loop);
-
-void birdloop_enter(struct birdloop *loop);
-void birdloop_leave(struct birdloop *loop);
-void birdloop_mask_wakeups(struct birdloop *loop);
-void birdloop_unmask_wakeups(struct birdloop *loop);
-
-
-#endif /* _BIRD_BFD_IO_H_ */
diff --git a/proto/bfd/packets.c b/proto/bfd/packets.c
index 5f10734c..6f0b4eaf 100644
--- a/proto/bfd/packets.c
+++ b/proto/bfd/packets.c
@@ -412,7 +412,7 @@ bfd_err_hook(sock *sk, int err)
 sock *
 bfd_open_rx_sk(struct bfd_proto *p, int multihop, int af)
 {
-  sock *sk = sk_new(p->tpool);
+  sock *sk = sk_new(p->p.pool);
   sk->type = SK_UDP;
   sk->subtype = af;
   sk->sport = !multihop ? BFD_CONTROL_PORT : BFD_MULTI_CTL_PORT;
@@ -475,7 +475,7 @@ bfd_open_rx_sk_bound(struct bfd_proto *p, ip_addr local, struct iface *ifa)
 sock *
 bfd_open_tx_sk(struct bfd_proto *p, ip_addr local, struct iface *ifa)
 {
-  sock *sk = sk_new(p->tpool);
+  sock *sk = sk_new(p->p.pool);
   sk->type = SK_UDP;
   sk->saddr = local;
   sk->dport = ifa ? BFD_CONTROL_PORT : BFD_MULTI_CTL_PORT;
diff --git a/proto/bgp/attrs.c b/proto/bgp/attrs.c
index 084c9b63..a7b1a7ed 100644
--- a/proto/bgp/attrs.c
+++ b/proto/bgp/attrs.c
@@ -1901,7 +1901,6 @@ bgp_out_table_export_start(struct rt_exporter *re, struct rt_export_request *req
   pool *p = rp_new(c->c.proto->pool, "Export hook");
   struct rt_export_hook *hook = mb_allocz(p, sizeof(struct rt_export_hook));
   hook->pool = p;
-  hook->lp = lp_new_default(p);
   hook->event = ev_new_init(p, bgp_out_table_feed, hook);
   hook->feed_type = TFT_HASH;
 
@@ -1919,6 +1918,7 @@ bgp_setup_out_table(struct bgp_channel *c)
   };
 
   init_list(&c->prefix_exporter.hooks);
+  init_list(&c->prefix_exporter.pending);
 
   c->c.out_table = &c->prefix_exporter;
 }
@@ -1929,10 +1929,10 @@ bgp_setup_out_table(struct bgp_channel *c)
  */
 
 int
-bgp_preexport(struct channel *c, rte *e)
+bgp_preexport(struct channel *C, rte *e)
 {
   struct proto *SRC = e->src->proto;
-  struct bgp_proto *p = (struct bgp_proto *) (c->proto);
+  struct bgp_proto *p = (struct bgp_proto *) C->proto;
   struct bgp_proto *src = (SRC->proto == &proto_bgp) ? (struct bgp_proto *) SRC : NULL;
 
   /* Reject our routes */
@@ -2546,27 +2546,57 @@ bgp_rte_recalculate(rtable *table, net *net, rte *new, rte *old, rte *old_best)
     return !old_suppressed;
 }
 
-rte *
-bgp_rte_modify_stale(struct rte *r, struct linpool *pool)
+void
+bgp_rte_modify_stale(struct rt_export_request *req, const net_addr *n, struct rt_pending_export *rpe UNUSED, rte **feed, uint count)
 {
-  eattr *ea = ea_find(r->attrs, BGP_EA_ID(BA_COMMUNITY));
-  const struct adata *ad = ea ? ea->u.ptr : NULL;
-  uint flags = ea ? ea->flags : BAF_PARTIAL;
+  struct bgp_channel *c = SKIP_BACK(struct bgp_channel, stale_feed, req);
+  struct rt_import_hook *irh = c->c.in_req.hook;
 
-  if (ad && int_set_contains(ad, BGP_COMM_NO_LLGR))
-    return NULL;
+  /* Find our routes among others */
+  for (uint i=0; i<count; i++)
+  {
+    rte *r = feed[i];
+
+    if (
+	!rte_is_valid(r) ||			/* Not a valid route */
+	(r->sender != irh) ||			/* Not our route */
+	(r->stale_cycle == irh->stale_set))	/* A new route, do not mark as stale */
+      continue;
+
+    eattr *ea = ea_find(r->attrs, BGP_EA_ID(BA_COMMUNITY));
+    const struct adata *ad = ea ? ea->u.ptr : NULL;
+    uint flags = ea ? ea->flags : BAF_PARTIAL;
 
-  if (ad && int_set_contains(ad, BGP_COMM_LLGR_STALE))
-    return r;
+    /* LLGR not allowed, withdraw the route */
+    if (ad && int_set_contains(ad, BGP_COMM_NO_LLGR))
+    {
+      rte_import(&c->c.in_req, n, NULL, r->src);
+      continue;
+    }
+
+    /* Route already marked as LLGR, do nothing */
+    if (ad && int_set_contains(ad, BGP_COMM_LLGR_STALE))
+      continue;
 
-  _Thread_local static rte e0;
-  e0 = *r;
+    /* Store the tmp_linpool state to aggresively save memory */
+    struct lp_state tmpp;
+    lp_save(tmp_linpool, &tmpp);
 
-  bgp_set_attr_ptr(&e0.attrs, BA_COMMUNITY, flags,
-		   int_set_add(pool, ad, BGP_COMM_LLGR_STALE));
-  e0.pflags |= BGP_REF_STALE;
+    /* Mark the route as LLGR */
+    rte e0 = *r;
+    bgp_set_attr_ptr(&e0.attrs, BA_COMMUNITY, flags, int_set_add(tmp_linpool, ad, BGP_COMM_LLGR_STALE));
+    e0.pflags &= ~BGP_REF_NOT_STALE;
+    e0.pflags |= BGP_REF_STALE;
 
-  return &e0;
+    /* We need to update the route but keep it stale. */
+    ASSERT_DIE(irh->stale_set == irh->stale_valid + 1);
+    irh->stale_set--;
+    rte_import(&c->c.in_req, n, &e0, r->src);
+    irh->stale_set++;
+
+    /* Restore the memory state */
+    lp_restore(tmp_linpool, &tmpp);
+  }
 }
 
 
diff --git a/proto/bgp/bgp.c b/proto/bgp/bgp.c
index 6ffe8824..33849b0b 100644
--- a/proto/bgp/bgp.c
+++ b/proto/bgp/bgp.c
@@ -139,6 +139,9 @@ static void bgp_update_bfd(struct bgp_proto *p, const struct bfd_options *bfd);
 static int bgp_incoming_connection(sock *sk, uint dummy UNUSED);
 static void bgp_listen_sock_err(sock *sk UNUSED, int err);
 
+static void bgp_graceful_restart_feed(struct bgp_channel *c);
+
+
 /**
  * bgp_open - open a BGP instance
  * @p: BGP instance
@@ -373,6 +376,7 @@ bgp_close_conn(struct bgp_conn *conn)
   conn->keepalive_timer = NULL;
   rfree(conn->hold_timer);
   conn->hold_timer = NULL;
+
   rfree(conn->tx_ev);
   conn->tx_ev = NULL;
   rfree(conn->sk);
@@ -511,6 +515,7 @@ void
 bgp_stop(struct bgp_proto *p, int subcode, byte *data, uint len)
 {
   proto_notify_state(&p->p, PS_STOP);
+  p->uncork_ev->data = NULL;
   bgp_graceful_close_conn(&p->outgoing_conn, subcode, data, len);
   bgp_graceful_close_conn(&p->incoming_conn, subcode, data, len);
   ev_schedule(p->event);
@@ -760,25 +765,25 @@ bgp_handle_graceful_restart(struct bgp_proto *p)
       {
       case BGP_GRS_NONE:
 	c->gr_active = BGP_GRS_ACTIVE;
-	rt_refresh_begin(c->c.table, &c->c.in_req);
+	rt_refresh_begin(&c->c.in_req);
 	break;
 
       case BGP_GRS_ACTIVE:
-	rt_refresh_end(c->c.table, &c->c.in_req);
-	rt_refresh_begin(c->c.table, &c->c.in_req);
+	rt_refresh_end(&c->c.in_req);
+	rt_refresh_begin(&c->c.in_req);
 	break;
 
       case BGP_GRS_LLGR:
-	rt_refresh_begin(c->c.table, &c->c.in_req);
-	rt_modify_stale(c->c.table, &c->c.in_req);
+	rt_refresh_begin(&c->c.in_req);
+	bgp_graceful_restart_feed(c);
 	break;
       }
     }
     else
     {
       /* Just flush the routes */
-      rt_refresh_begin(c->c.table, &c->c.in_req);
-      rt_refresh_end(c->c.table, &c->c.in_req);
+      rt_refresh_begin(&c->c.in_req);
+      rt_refresh_end(&c->c.in_req);
     }
 
     /* Reset bucket and prefix tables */
@@ -796,6 +801,53 @@ bgp_handle_graceful_restart(struct bgp_proto *p)
   tm_start(p->gr_timer, p->conn->remote_caps->gr_time S);
 }
 
+static void
+bgp_graceful_restart_feed_done(struct rt_export_request *req)
+{
+  req->hook = NULL;
+}
+
+static void
+bgp_graceful_restart_feed_dump_req(struct rt_export_request *req)
+{
+  struct bgp_channel *c = SKIP_BACK(struct bgp_channel, stale_feed, req);
+  debug("  BGP-GR %s.%s export request %p\n", c->c.proto->name, c->c.name, req);
+}
+
+static void
+bgp_graceful_restart_feed_log_state_change(struct rt_export_request *req, u8 state)
+{
+  struct bgp_channel *c = SKIP_BACK(struct bgp_channel, stale_feed, req);
+  struct bgp_proto *p = (void *) c->c.proto;
+  BGP_TRACE(D_EVENTS, "Long-lived graceful restart export state changed to %s", rt_export_state_name(state));
+
+  if (state == TES_READY)
+    rt_stop_export(req, bgp_graceful_restart_feed_done);
+}
+
+static void
+bgp_graceful_restart_drop_export(struct rt_export_request *req UNUSED, const net_addr *n UNUSED, struct rt_pending_export *rpe UNUSED)
+{ /* Nothing to do */ }
+
+static void
+bgp_graceful_restart_feed(struct bgp_channel *c)
+{
+  c->stale_feed = (struct rt_export_request) {
+    .name = "BGP-GR",
+    .list = &global_work_list,
+    .trace_routes = c->c.debug | c->c.proto->debug,
+    .dump_req = bgp_graceful_restart_feed_dump_req,
+    .log_state_change = bgp_graceful_restart_feed_log_state_change,
+    .export_bulk = bgp_rte_modify_stale,
+    .export_one = bgp_graceful_restart_drop_export,
+  };
+
+  rt_request_export(&c->c.table->exporter, &c->stale_feed);
+}
+
+
+
+
 /**
  * bgp_graceful_restart_done - finish active BGP graceful restart
  * @c: BGP channel
@@ -819,7 +871,7 @@ bgp_graceful_restart_done(struct bgp_channel *c)
     BGP_TRACE(D_EVENTS, "Neighbor graceful restart done");
 
   tm_stop(c->stale_timer);
-  rt_refresh_end(c->c.table, &c->c.in_req);
+  rt_refresh_end(&c->c.in_req);
 }
 
 /**
@@ -861,7 +913,7 @@ bgp_graceful_restart_timeout(timer *t)
       /* Channel is in GR, and supports LLGR -> start LLGR */
       c->gr_active = BGP_GRS_LLGR;
       tm_start(c->stale_timer, c->stale_time S);
-      rt_modify_stale(c->c.table, &c->c.in_req);
+      bgp_graceful_restart_feed(c);
     }
   }
   else
@@ -899,7 +951,7 @@ bgp_refresh_begin(struct bgp_channel *c)
   { log(L_WARN "%s: BEGIN-OF-RR received before END-OF-RIB, ignoring", p->p.name); return; }
 
   c->load_state = BFS_REFRESHING;
-  rt_refresh_begin(c->c.table, &c->c.in_req);
+  rt_refresh_begin(&c->c.in_req);
 }
 
 /**
@@ -920,7 +972,7 @@ bgp_refresh_end(struct bgp_channel *c)
   { log(L_WARN "%s: END-OF-RR received without prior BEGIN-OF-RR, ignoring", p->p.name); return; }
 
   c->load_state = BFS_NONE;
-  rt_refresh_end(c->c.table, &c->c.in_req);
+  rt_refresh_end(&c->c.in_req);
 }
 
 
@@ -1526,6 +1578,8 @@ bgp_start(struct proto *P)
   p->last_rx_update = 0;
 
   p->event = ev_new_init(p->p.pool, bgp_decision, p);
+  p->uncork_ev = ev_new_init(p->p.pool, bgp_uncork, p);
+
   p->startup_timer = tm_new_init(p->p.pool, bgp_startup_timeout, p, 0, 0);
   p->gr_timer = tm_new_init(p->p.pool, bgp_graceful_restart_timeout, p, 0, 0);
 
@@ -1672,7 +1726,6 @@ bgp_init(struct proto_config *CF)
   P->rte_better = bgp_rte_better;
   P->rte_mergable = bgp_rte_mergable;
   P->rte_recalculate = cf->deterministic_med ? bgp_rte_recalculate : NULL;
-  P->rte_modify = bgp_rte_modify_stale;
   P->rte_igp_metric = bgp_rte_igp_metric;
 
   p->cf = cf;
diff --git a/proto/bgp/bgp.h b/proto/bgp/bgp.h
index 003893e0..469f0cb9 100644
--- a/proto/bgp/bgp.h
+++ b/proto/bgp/bgp.h
@@ -319,6 +319,7 @@ struct bgp_proto {
   struct bgp_socket *sock;		/* Shared listening socket */
   struct bfd_request *bfd_req;		/* BFD request, if BFD is used */
   struct birdsock *postponed_sk;	/* Postponed incoming socket for dynamic BGP */
+  event *uncork_ev;			/* Uncork event in case of congestion */
   struct bgp_stats stats;		/* BGP statistics */
   btime last_established;		/* Last time of enter/leave of established state */
   btime last_rx_update;			/* Last time of RX update */
@@ -371,6 +372,7 @@ struct bgp_channel {
 
   timer *stale_timer;			/* Long-lived stale timer for LLGR */
   u32 stale_time;			/* Stored LLGR stale time from last session */
+  struct rt_export_request stale_feed;	/* Feeder request for stale route modification */
 
   u8 add_path_rx;			/* Session expects receive of ADD-PATH extended NLRI */
   u8 add_path_tx;			/* Session expects transmit of ADD-PATH extended NLRI */
@@ -576,7 +578,7 @@ void bgp_done_prefix(struct bgp_channel *c, struct bgp_prefix *px, struct bgp_bu
 int bgp_rte_better(struct rte *, struct rte *);
 int bgp_rte_mergable(rte *pri, rte *sec);
 int bgp_rte_recalculate(rtable *table, net *net, rte *new, rte *old, rte *old_best);
-struct rte *bgp_rte_modify_stale(struct rte *r, struct linpool *pool);
+void bgp_rte_modify_stale(struct rt_export_request *req, const net_addr *n, struct rt_pending_export *rpe UNUSED, rte **feed, uint count);
 u32 bgp_rte_igp_metric(const rte *);
 void bgp_rt_notify(struct proto *P, struct channel *C, const net_addr *n, rte *new, const rte *old);
 int bgp_preexport(struct channel *, struct rte *);
@@ -609,6 +611,7 @@ void bgp_schedule_packet(struct bgp_conn *conn, struct bgp_channel *c, int type)
 void bgp_kick_tx(void *vconn);
 void bgp_tx(struct birdsock *sk);
 int bgp_rx(struct birdsock *sk, uint size);
+void bgp_uncork(void *vp);
 const char * bgp_error_dsc(unsigned code, unsigned subcode);
 void bgp_log_error(struct bgp_proto *p, u8 class, char *msg, unsigned code, unsigned subcode, byte *data, unsigned len);
 
diff --git a/proto/bgp/packets.c b/proto/bgp/packets.c
index 4d4ae3eb..de976588 100644
--- a/proto/bgp/packets.c
+++ b/proto/bgp/packets.c
@@ -3175,6 +3175,21 @@ bgp_rx_packet(struct bgp_conn *conn, byte *pkt, uint len)
   }
 }
 
+void
+bgp_uncork(void *vp)
+{
+  struct bgp_proto *p = vp;
+
+  if (p && p->conn && (p->conn->state == BS_ESTABLISHED) && !p->conn->sk->rx_hook)
+  {
+    struct birdsock *sk = p->conn->sk;
+    ASSERT_DIE(sk->rpos > sk->rbuf);
+    sk->rx_hook = bgp_rx;
+    bgp_rx(sk, sk->rpos - sk->rbuf);
+    BGP_TRACE(D_PACKETS, "Uncorked");
+  }
+}
+
 /**
  * bgp_rx - handle received data
  * @sk: socket
@@ -3189,6 +3204,7 @@ int
 bgp_rx(sock *sk, uint size)
 {
   struct bgp_conn *conn = sk->data;
+  struct bgp_proto *p = conn->bgp;
   byte *pkt_start = sk->rbuf;
   byte *end = pkt_start + size;
   uint i, len;
@@ -3198,6 +3214,12 @@ bgp_rx(sock *sk, uint size)
     {
       if ((conn->state == BS_CLOSE) || (conn->sk != sk))
 	return 0;
+      if ((conn->state == BS_ESTABLISHED) && rt_cork_check(conn->bgp->uncork_ev))
+      {
+	sk->rx_hook = NULL;
+	BGP_TRACE(D_PACKETS, "Corked");
+	return 0;
+      }
       for(i=0; i<16; i++)
 	if (pkt_start[i] != 0xff)
 	  {
diff --git a/proto/ospf/ospf.c b/proto/ospf/ospf.c
index 6a4ee8ab..9c25f0f0 100644
--- a/proto/ospf/ospf.c
+++ b/proto/ospf/ospf.c
@@ -486,13 +486,13 @@ ospf_disp(timer * timer)
  * import to the filters.
  */
 static int
-ospf_preexport(struct channel *c, rte *e)
+ospf_preexport(struct channel *C, rte *e)
 {
-  struct ospf_proto *p = (struct ospf_proto *) c->proto;
+  struct ospf_proto *p = (struct ospf_proto *) C->proto;
   struct ospf_area *oa = ospf_main_area(p);
 
   /* Reject our own routes */
-  if (e->src->proto == c->proto)
+  if (e->src->proto == &p->p)
     return -1;
 
   /* Do not export routes to stub areas */
diff --git a/proto/pipe/pipe.c b/proto/pipe/pipe.c
index 351db36b..8af6de81 100644
--- a/proto/pipe/pipe.c
+++ b/proto/pipe/pipe.c
@@ -73,12 +73,12 @@ pipe_rt_notify(struct proto *P, struct channel *src_ch, const net_addr *n, rte *
 }
 
 static int
-pipe_preexport(struct channel *c, rte *e)
+pipe_preexport(struct channel *C, rte *e)
 {
-  struct pipe_proto *p = (void *) c->proto;
+  struct pipe_proto *p = (void *) C->proto;
 
   /* Avoid direct loopbacks */
-  if (e->sender == c->in_req.hook)
+  if (e->sender == C->in_req.hook)
     return -1;
 
   /* Indirection check */
@@ -86,8 +86,8 @@ pipe_preexport(struct channel *c, rte *e)
   if (e->generation >= max_generation)
   {
     log_rl(&p->rl_gen, L_ERR "Route overpiped (%u hops of %u configured in %s) in table %s: %N %s/%u:%u",
-	e->generation, max_generation, c->proto->name,
-	c->table->name, e->net, e->src->proto->name, e->src->private_id, e->src->global_id);
+	e->generation, max_generation, C->proto->name,
+	C->table->name, e->net, e->src->proto->name, e->src->private_id, e->src->global_id);
 
     return -1;
   }
diff --git a/proto/radv/radv.c b/proto/radv/radv.c
index 3a159462..10d5e3ed 100644
--- a/proto/radv/radv.c
+++ b/proto/radv/radv.c
@@ -394,10 +394,10 @@ radv_net_match_trigger(struct radv_config *cf, const net_addr *n)
 }
 
 int
-radv_preexport(struct channel *c, rte *new)
+radv_preexport(struct channel *C, rte *new)
 {
   // struct radv_proto *p = (struct radv_proto *) P;
-  struct radv_config *cf = (struct radv_config *) (c->proto->cf);
+  struct radv_config *cf = (struct radv_config *) (C->proto->cf);
 
   if (radv_net_match_trigger(cf, new->net))
     return RIC_PROCESS;
diff --git a/proto/rpki/packets.c b/proto/rpki/packets.c
index 4a52b54b..108da61b 100644
--- a/proto/rpki/packets.c
+++ b/proto/rpki/packets.c
@@ -661,9 +661,9 @@ rpki_handle_cache_response_pdu(struct rpki_cache *cache, const struct pdu_cache_
        * a refresh cycle.
        */
       if (cache->p->roa4_channel)
-	rt_refresh_begin(cache->p->roa4_channel->table, &cache->p->roa4_channel->in_req);
+	rt_refresh_begin(&cache->p->roa4_channel->in_req);
       if (cache->p->roa6_channel)
-	rt_refresh_begin(cache->p->roa6_channel->table, &cache->p->roa6_channel->in_req);
+	rt_refresh_begin(&cache->p->roa6_channel->in_req);
 
       cache->p->refresh_channels = 1;
     }
@@ -846,9 +846,9 @@ rpki_handle_end_of_data_pdu(struct rpki_cache *cache, const struct pdu_end_of_da
   {
     cache->p->refresh_channels = 0;
     if (cache->p->roa4_channel)
-      rt_refresh_end(cache->p->roa4_channel->table, &cache->p->roa4_channel->in_req);
+      rt_refresh_end(&cache->p->roa4_channel->in_req);
     if (cache->p->roa6_channel)
-      rt_refresh_end(cache->p->roa6_channel->table, &cache->p->roa6_channel->in_req);
+      rt_refresh_end(&cache->p->roa6_channel->in_req);
   }
 
   cache->last_update = current_time();
diff --git a/proto/static/config.Y b/proto/static/config.Y
index 41e10dbf..9d26ee82 100644
--- a/proto/static/config.Y
+++ b/proto/static/config.Y
@@ -40,7 +40,7 @@ static_route_finish(void)
   if (net_type_match(this_srt->net, NB_DEST) == !this_srt->dest)
     cf_error("Unexpected or missing nexthop/type");
 
-  this_srt->cmds = f_linearize(this_srt_cmds);
+  this_srt->cmds = f_linearize(this_srt_cmds, 0);
 }
 
 CF_DECLS
diff --git a/sysdep/config.h b/sysdep/config.h
index b0531844..5cdadbb0 100644
--- a/sysdep/config.h
+++ b/sysdep/config.h
@@ -13,7 +13,7 @@
 #ifdef GIT_LABEL
 #define BIRD_VERSION XSTR1(GIT_LABEL)
 #else
-#define BIRD_VERSION "2.0.9"
+#define BIRD_VERSION "2.0.10"
 #endif
 
 /* Include parameters determined by configure script */
diff --git a/sysdep/unix/Makefile b/sysdep/unix/Makefile
index 51ab98a9..3f1a8b3a 100644
--- a/sysdep/unix/Makefile
+++ b/sysdep/unix/Makefile
@@ -1,4 +1,4 @@
-src := alloc.c io.c krt.c log.c main.c random.c
+src := alloc.c io.c io-loop.c krt.c log.c main.c random.c domain.c
 obj := $(src-o-files)
 $(all-daemon)
 $(cf-local)
diff --git a/sysdep/unix/alloc.c b/sysdep/unix/alloc.c
index edad6209..a2384ca8 100644
--- a/sysdep/unix/alloc.c
+++ b/sysdep/unix/alloc.c
@@ -97,7 +97,7 @@ alloc_page(void)
     struct free_page *fp = SKIP_BACK(struct free_page, n, HEAD(fps->pages));
     rem_node(&fp->n);
     if ((--fps->cnt < fps->min) && !shutting_down)
-      ev_schedule(&fps->cleanup);
+      ev_send(&global_work_list, &fps->cleanup);
 
     bzero(fp, page_size);
     return fp;
@@ -124,7 +124,7 @@ free_page(void *ptr)
   add_tail(&fps->pages, &fp->n);
 
   if ((++fps->cnt > fps->max) && !shutting_down)
-    ev_schedule(&fps->cleanup);
+    ev_send(&global_work_list, &fps->cleanup);
 #endif
 }
 
diff --git a/sysdep/unix/domain.c b/sysdep/unix/domain.c
new file mode 100644
index 00000000..0a5858a6
--- /dev/null
+++ b/sysdep/unix/domain.c
@@ -0,0 +1,116 @@
+/*
+ *	BIRD Locking
+ *
+ *	(c) 2020 Maria Matejka <mq@jmq.cz>
+ *
+ *	Can be freely distributed and used under the terms of the GNU GPL.
+ */
+
+#ifndef _GNU_SOURCE
+#define _GNU_SOURCE
+#endif
+
+#undef LOCAL_DEBUG
+
+#undef DEBUG_LOCKING
+
+#include "lib/birdlib.h"
+#include "lib/locking.h"
+#include "lib/resource.h"
+#include "lib/timer.h"
+
+#include "conf/conf.h"
+
+#include <errno.h>
+#include <fcntl.h>
+#include <poll.h>
+#include <pthread.h>
+#include <semaphore.h>
+#include <stdatomic.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+/*
+ *	Locking subsystem
+ */
+
+_Thread_local struct lock_order locking_stack = {};
+_Thread_local struct domain_generic **last_locked = NULL;
+
+#define ASSERT_NO_LOCK	ASSERT_DIE(last_locked == NULL)
+
+struct domain_generic {
+  pthread_mutex_t mutex;
+  uint order;
+  struct domain_generic **prev;
+  struct lock_order *locked_by;
+  const char *name;
+};
+
+#define DOMAIN_INIT(_name, _order) { .mutex = PTHREAD_MUTEX_INITIALIZER, .name = _name, .order = _order }
+
+static struct domain_generic the_bird_domain_gen = DOMAIN_INIT("The BIRD", OFFSETOF(struct lock_order, the_bird));
+
+DOMAIN(the_bird) the_bird_domain = { .the_bird = &the_bird_domain_gen };
+
+struct domain_generic *
+domain_new(const char *name, uint order)
+{
+  ASSERT_DIE(order < sizeof(struct lock_order));
+  struct domain_generic *dg = xmalloc(sizeof(struct domain_generic));
+  *dg = (struct domain_generic) DOMAIN_INIT(name, order);
+  return dg;
+}
+
+void
+domain_free(struct domain_generic *dg)
+{
+  pthread_mutex_destroy(&dg->mutex);
+  xfree(dg);
+}
+
+uint dg_order(struct domain_generic *dg)
+{
+  return dg->order;
+}
+
+void do_lock(struct domain_generic *dg, struct domain_generic **lsp)
+{
+  if ((char *) lsp - (char *) &locking_stack != dg->order)
+    bug("Trying to lock on bad position: order=%u, lsp=%p, base=%p", dg->order, lsp, &locking_stack);
+
+  if (lsp <= last_locked)
+    bug("Trying to lock in a bad order");
+  if (*lsp)
+    bug("Inconsistent locking stack state on lock");
+
+  btime lock_begin = current_time();
+  pthread_mutex_lock(&dg->mutex);
+  btime duration = current_time() - lock_begin;
+  if (config && (duration > config->watchdog_warning))
+    log(L_WARN "Locking of %s took %d ms", dg->name, (int) (duration TO_MS));
+
+  if (dg->prev || dg->locked_by)
+    bug("Previous unlock not finished correctly");
+  dg->prev = last_locked;
+  *lsp = dg;
+  last_locked = lsp;
+  dg->locked_by = &locking_stack;
+}
+
+void do_unlock(struct domain_generic *dg, struct domain_generic **lsp)
+{
+  if ((char *) lsp - (char *) &locking_stack != dg->order)
+    bug("Trying to unlock on bad position: order=%u, lsp=%p, base=%p", dg->order, lsp, &locking_stack);
+
+  if (dg->locked_by != &locking_stack)
+    bug("Inconsistent domain state on unlock");
+  if ((last_locked != lsp) || (*lsp != dg))
+    bug("Inconsistent locking stack state on unlock");
+  dg->locked_by = NULL;
+  last_locked = dg->prev;
+  *lsp = NULL;
+  dg->prev = NULL;
+  pthread_mutex_unlock(&dg->mutex);
+}
diff --git a/proto/bfd/io.c b/sysdep/unix/io-loop.c
index e696cc89..3e3fc31a 100644
--- a/proto/bfd/io.c
+++ b/sysdep/unix/io-loop.c
@@ -15,7 +15,6 @@
 #include <sys/time.h>
 
 #include "nest/bird.h"
-#include "proto/bfd/io.h"
 
 #include "lib/buffer.h"
 #include "lib/lists.h"
@@ -24,56 +23,41 @@
 #include "lib/timer.h"
 #include "lib/socket.h"
 
+#include "lib/io-loop.h"
+#include "sysdep/unix/io-loop.h"
+#include "conf/conf.h"
 
-struct birdloop
-{
-  pool *pool;
-  pthread_t thread;
-  pthread_mutex_t mutex;
-
-  u8 stop_called;
-  u8 poll_active;
-  u8 wakeup_masked;
-  int wakeup_fds[2];
-
-  struct timeloop time;
-  list event_list;
-  list sock_list;
-  uint sock_num;
-
-  BUFFER(sock *) poll_sk;
-  BUFFER(struct pollfd) poll_fd;
-  u8 poll_changed;
-  u8 close_scheduled;
-};
-
+#define THREAD_STACK_SIZE	65536	/* To be lowered in near future */
 
 /*
  *	Current thread context
  */
 
-static pthread_key_t current_loop_key;
-extern pthread_key_t current_time_key;
+_Thread_local struct birdloop *birdloop_current;
+static _Thread_local struct birdloop *birdloop_wakeup_masked;
+static _Thread_local uint birdloop_wakeup_masked_count;
 
-static inline struct birdloop *
-birdloop_current(void)
+event_list *
+birdloop_event_list(struct birdloop *loop)
 {
-  return pthread_getspecific(current_loop_key);
+  return &loop->event_list;
 }
 
-static inline void
-birdloop_set_current(struct birdloop *loop)
+struct timeloop *
+birdloop_time_loop(struct birdloop *loop)
 {
-  pthread_setspecific(current_loop_key, loop);
-  pthread_setspecific(current_time_key, loop ? &loop->time : &main_timeloop);
+  return &loop->time;
 }
 
-static inline void
-birdloop_init_current(void)
+_Bool
+birdloop_inside(struct birdloop *loop)
 {
-  pthread_key_create(&current_loop_key, NULL);
-}
+  for (struct birdloop *c = birdloop_current; c; c = c->prev_loop)
+    if (loop == c)
+      return 1;
 
+  return 0;
+}
 
 /*
  *	Wakeup code for birdloop
@@ -150,60 +134,24 @@ wakeup_do_kick(struct birdloop *loop)
 }
 
 static inline void
-wakeup_kick(struct birdloop *loop)
-{
-  if (!loop->wakeup_masked)
-    wakeup_do_kick(loop);
-  else
-    loop->wakeup_masked = 2;
-}
-
-/* For notifications from outside */
-void
-wakeup_kick_current(void)
+birdloop_do_ping(struct birdloop *loop)
 {
-  struct birdloop *loop = birdloop_current();
+  if (atomic_fetch_add_explicit(&loop->ping_sent, 1, memory_order_acq_rel))
+    return;
 
-  if (loop && loop->poll_active)
-    wakeup_kick(loop);
-}
-
-
-/*
- *	Events
- */
-
-static inline uint
-events_waiting(struct birdloop *loop)
-{
-  return !EMPTY_LIST(loop->event_list);
-}
-
-static inline void
-events_init(struct birdloop *loop)
-{
-  init_list(&loop->event_list);
-}
-
-static void
-events_fire(struct birdloop *loop)
-{
-  times_update(&loop->time);
-  ev_run_list(&loop->event_list);
+  if (loop == birdloop_wakeup_masked)
+    birdloop_wakeup_masked_count++;
+  else
+    wakeup_do_kick(loop);
 }
 
 void
-ev2_schedule(event *e)
+birdloop_ping(struct birdloop *loop)
 {
-  struct birdloop *loop = birdloop_current();
-
-  if (loop->poll_active && EMPTY_LIST(loop->event_list))
-    wakeup_kick(loop);
-
-  if (e->n.next)
-    rem_node(&e->n);
-
-  add_tail(&loop->event_list, &e->n);
+  if (birdloop_inside(loop) && !loop->ping_pending)
+    loop->ping_pending++;
+  else
+    birdloop_do_ping(loop);
 }
 
 
@@ -231,16 +179,14 @@ sockets_add(struct birdloop *loop, sock *s)
   s->index = -1;
   loop->poll_changed = 1;
 
-  if (loop->poll_active)
-    wakeup_kick(loop);
+  birdloop_ping(loop);
 }
 
 void
 sk_start(sock *s)
 {
-  struct birdloop *loop = birdloop_current();
-
-  sockets_add(loop, s);
+  ASSERT_DIE(birdloop_current != &main_birdloop);
+  sockets_add(birdloop_current, s);
 }
 
 static void
@@ -250,30 +196,21 @@ sockets_remove(struct birdloop *loop, sock *s)
   loop->sock_num--;
 
   if (s->index >= 0)
-    loop->poll_sk.data[s->index] = NULL;
-
-  s->index = -1;
-  loop->poll_changed = 1;
-
-  /* Wakeup moved to sk_stop() */
-}
-
-void
-sk_stop(sock *s)
-{
-  struct birdloop *loop = birdloop_current();
-
-  sockets_remove(loop, s);
-
-  if (loop->poll_active)
   {
+    loop->poll_sk.data[s->index] = NULL;
+    s->index = -1;
+    loop->poll_changed = 1;
     loop->close_scheduled = 1;
-    wakeup_kick(loop);
+    birdloop_ping(loop);
   }
   else
     close(s->fd);
+}
 
-  s->fd = -1;
+void
+sk_stop(sock *s)
+{
+  sockets_remove(birdloop_current, s);
 }
 
 static inline uint sk_want_events(sock *s)
@@ -354,7 +291,7 @@ sockets_fire(struct birdloop *loop)
   sock **psk = loop->poll_sk.data;
   int poll_num = loop->poll_fd.used - 1;
 
-  times_update(&loop->time);
+  times_update();
 
   /* Last fd is internal wakeup fd */
   if (pfd[poll_num].revents & POLLIN)
@@ -373,12 +310,15 @@ sockets_fire(struct birdloop *loop)
 
     if (pfd->revents & POLLIN)
       while (e && *psk && (*psk)->rx_hook)
-	e = sk_read(*psk, 0);
+	e = sk_read(*psk, pfd->revents);
 
     e = 1;
     if (pfd->revents & POLLOUT)
+    {
+      loop->poll_changed = 1;
       while (e && *psk)
 	e = sk_write(*psk);
+    }
   }
 }
 
@@ -387,90 +327,176 @@ sockets_fire(struct birdloop *loop)
  *	Birdloop
  */
 
-static void * birdloop_main(void *arg);
+struct birdloop main_birdloop;
+
+static void birdloop_enter_locked(struct birdloop *loop);
+
+void
+birdloop_init(void)
+{
+  wakeup_init(&main_birdloop);
+
+  main_birdloop.time.domain = the_bird_domain.the_bird;
+  main_birdloop.time.loop = &main_birdloop;
+
+  times_update();
+  timers_init(&main_birdloop.time, &root_pool);
+
+  birdloop_enter_locked(&main_birdloop);
+}
+
+static void *birdloop_main(void *arg);
 
 struct birdloop *
-birdloop_new(void)
+birdloop_new(pool *pp, uint order, const char *name)
 {
-  /* FIXME: this init should be elsewhere and thread-safe */
-  static int init = 0;
-  if (!init)
-    { birdloop_init_current(); init = 1; }
+  struct domain_generic *dg = domain_new(name, order);
 
-  pool *p = rp_new(NULL, "Birdloop root");
+  pool *p = rp_new(pp, name);
   struct birdloop *loop = mb_allocz(p, sizeof(struct birdloop));
   loop->pool = p;
-  pthread_mutex_init(&loop->mutex, NULL);
 
-  wakeup_init(loop);
+  loop->time.domain = dg;
+  loop->time.loop = loop;
+
+  birdloop_enter(loop);
 
-  events_init(loop);
+  wakeup_init(loop);
+  ev_init_list(&loop->event_list, loop, name);
   timers_init(&loop->time, p);
   sockets_init(loop);
 
+  int e = 0;
+
+  if (e = pthread_attr_init(&loop->thread_attr))
+    die("pthread_attr_init() failed: %M", e);
+
+  if (e = pthread_attr_setstacksize(&loop->thread_attr, THREAD_STACK_SIZE))
+    die("pthread_attr_setstacksize(%u) failed: %M", THREAD_STACK_SIZE, e);
+
+  if (e = pthread_attr_setdetachstate(&loop->thread_attr, PTHREAD_CREATE_DETACHED))
+    die("pthread_attr_setdetachstate(PTHREAD_CREATE_DETACHED) failed: %M", e);
+
+  if (e = pthread_create(&loop->thread_id, &loop->thread_attr, birdloop_main, loop))
+    die("pthread_create() failed: %M", e);
+
+  birdloop_leave(loop);
+
   return loop;
 }
 
+static void
+birdloop_do_stop(struct birdloop *loop, void (*stopped)(void *data), void *data)
+{
+  loop->stopped = stopped;
+  loop->stop_data = data;
+  wakeup_do_kick(loop);
+}
+
 void
-birdloop_start(struct birdloop *loop)
+birdloop_stop(struct birdloop *loop, void (*stopped)(void *data), void *data)
 {
-  int rv = pthread_create(&loop->thread, NULL, birdloop_main, loop);
-  if (rv)
-    die("pthread_create(): %M", rv);
+  DG_LOCK(loop->time.domain);
+  birdloop_do_stop(loop, stopped, data);
+  DG_UNLOCK(loop->time.domain);
 }
 
 void
-birdloop_stop(struct birdloop *loop)
+birdloop_stop_self(struct birdloop *loop, void (*stopped)(void *data), void *data)
 {
-  pthread_mutex_lock(&loop->mutex);
-  loop->stop_called = 1;
-  wakeup_do_kick(loop);
-  pthread_mutex_unlock(&loop->mutex);
+  ASSERT_DIE(loop == birdloop_current);
+  ASSERT_DIE(DG_IS_LOCKED(loop->time.domain));
 
-  int rv = pthread_join(loop->thread, NULL);
-  if (rv)
-    die("pthread_join(): %M", rv);
+  birdloop_do_stop(loop, stopped, data);
 }
 
 void
 birdloop_free(struct birdloop *loop)
 {
+  ASSERT_DIE(loop->links == 0);
+  ASSERT_DIE(pthread_equal(pthread_self(), loop->thread_id));
+
+  rcu_birdloop_stop(&loop->rcu);
+  pthread_attr_destroy(&loop->thread_attr);
+
+  domain_free(loop->time.domain);
   rfree(loop->pool);
 }
 
+static void
+birdloop_enter_locked(struct birdloop *loop)
+{
+  ASSERT_DIE(DG_IS_LOCKED(loop->time.domain));
+  ASSERT_DIE(!birdloop_inside(loop));
+
+  /* Store the old context */
+  loop->prev_loop = birdloop_current;
+
+  /* Put the new context */
+  birdloop_current = loop;
+}
 
 void
 birdloop_enter(struct birdloop *loop)
 {
-  /* TODO: these functions could save and restore old context */
-  pthread_mutex_lock(&loop->mutex);
-  birdloop_set_current(loop);
+  DG_LOCK(loop->time.domain);
+  return birdloop_enter_locked(loop);
+}
+
+static void
+birdloop_leave_locked(struct birdloop *loop)
+{
+  /* Check the current context */
+  ASSERT_DIE(birdloop_current == loop);
+
+  /* Send pending pings */
+  if (loop->ping_pending)
+  {
+    loop->ping_pending = 0;
+    birdloop_do_ping(loop);
+  }
+
+  /* Restore the old context */
+  birdloop_current = loop->prev_loop;
 }
 
 void
 birdloop_leave(struct birdloop *loop)
 {
-  /* TODO: these functions could save and restore old context */
-  birdloop_set_current(NULL);
-  pthread_mutex_unlock(&loop->mutex);
+  birdloop_leave_locked(loop);
+  DG_UNLOCK(loop->time.domain);
 }
 
 void
 birdloop_mask_wakeups(struct birdloop *loop)
 {
-  pthread_mutex_lock(&loop->mutex);
-  loop->wakeup_masked = 1;
-  pthread_mutex_unlock(&loop->mutex);
+  ASSERT_DIE(birdloop_wakeup_masked == NULL);
+  birdloop_wakeup_masked = loop;
 }
 
 void
 birdloop_unmask_wakeups(struct birdloop *loop)
 {
-  pthread_mutex_lock(&loop->mutex);
-  if (loop->wakeup_masked == 2)
+  ASSERT_DIE(birdloop_wakeup_masked == loop);
+  birdloop_wakeup_masked = NULL;
+  if (birdloop_wakeup_masked_count)
     wakeup_do_kick(loop);
-  loop->wakeup_masked = 0;
-  pthread_mutex_unlock(&loop->mutex);
+
+  birdloop_wakeup_masked_count = 0;
+}
+
+void
+birdloop_link(struct birdloop *loop)
+{
+  ASSERT_DIE(birdloop_inside(loop));
+  loop->links++;
+}
+
+void
+birdloop_unlink(struct birdloop *loop)
+{
+  ASSERT_DIE(birdloop_inside(loop));
+  loop->links--;
 }
 
 static void *
@@ -480,18 +506,17 @@ birdloop_main(void *arg)
   timer *t;
   int rv, timeout;
 
-  birdloop_set_current(loop);
+  rcu_birdloop_start(&loop->rcu);
+
+  btime loop_begin = current_time();
 
   tmp_init(loop->pool);
 
-  pthread_mutex_lock(&loop->mutex);
+  birdloop_enter(loop);
   while (1)
   {
-    events_fire(loop);
-    timers_fire(&loop->time);
-
-    times_update(&loop->time);
-    if (events_waiting(loop))
+    timers_fire(&loop->time, 0);
+    if (ev_run_list(&loop->event_list))
       timeout = 0;
     else if (t = timers_first(&loop->time))
       timeout = (tm_remains(t) TO_MS) + 1;
@@ -501,8 +526,11 @@ birdloop_main(void *arg)
     if (loop->poll_changed)
       sockets_prepare(loop);
 
-    loop->poll_active = 1;
-    pthread_mutex_unlock(&loop->mutex);
+    btime duration = current_time() - loop_begin;
+    if (duration > config->watchdog_warning)
+      log(L_WARN "I/O loop cycle took %d ms", (int) (duration TO_MS));
+
+    birdloop_leave(loop);
 
   try:
     rv = poll(loop->poll_fd.data, loop->poll_fd.used, timeout);
@@ -513,25 +541,38 @@ birdloop_main(void *arg)
       die("poll: %m");
     }
 
-    pthread_mutex_lock(&loop->mutex);
-    loop->poll_active = 0;
+    birdloop_enter(loop);
 
     if (loop->close_scheduled)
       sockets_close_fds(loop);
 
-    if (loop->stop_called)
+    if (loop->stopped)
       break;
 
+    loop_begin = current_time();
+
     if (rv)
       sockets_fire(loop);
 
-    timers_fire(&loop->time);
+    atomic_exchange_explicit(&loop->ping_sent, 0, memory_order_acq_rel);
   }
 
-  loop->stop_called = 0;
-  pthread_mutex_unlock(&loop->mutex);
+  /* Flush remaining events */
+  ASSERT_DIE(!ev_run_list(&loop->event_list));
+
+  /* No timers allowed */
+  ASSERT_DIE(timers_count(&loop->time) == 0);
+  ASSERT_DIE(EMPTY_LIST(loop->sock_list));
+  ASSERT_DIE(loop->sock_num == 0);
+
+  birdloop_leave(loop);
+  loop->stopped(loop->stop_data);
 
   return NULL;
 }
 
-
+void
+birdloop_yield(void)
+{
+  usleep(100);
+}
diff --git a/sysdep/unix/io-loop.h b/sysdep/unix/io-loop.h
new file mode 100644
index 00000000..31c40459
--- /dev/null
+++ b/sysdep/unix/io-loop.h
@@ -0,0 +1,43 @@
+/*
+ *	BIRD -- I/O and event loop
+ *
+ *	Can be freely distributed and used under the terms of the GNU GPL.
+ */
+
+#ifndef _BIRD_SYSDEP_UNIX_IO_LOOP_H_
+#define _BIRD_SYSDEP_UNIX_IO_LOOP_H_
+
+#include "lib/rcu.h"
+
+struct birdloop
+{
+  pool *pool;
+
+  struct timeloop time;
+  event_list event_list;
+  list sock_list;
+  uint sock_num;
+
+  BUFFER(sock *) poll_sk;
+  BUFFER(struct pollfd) poll_fd;
+  u8 poll_changed;
+  u8 close_scheduled;
+
+  uint ping_pending;
+  _Atomic u32 ping_sent;
+  int wakeup_fds[2];
+
+  pthread_t thread_id;
+  pthread_attr_t thread_attr;
+
+  struct rcu_birdloop rcu;
+
+  uint links;
+
+  void (*stopped)(void *data);
+  void *stop_data;
+
+  struct birdloop *prev_loop;
+};
+
+#endif
diff --git a/sysdep/unix/io.c b/sysdep/unix/io.c
index 8a116789..23baffb2 100644
--- a/sysdep/unix/io.c
+++ b/sysdep/unix/io.c
@@ -36,12 +36,14 @@
 #include "lib/resource.h"
 #include "lib/socket.h"
 #include "lib/event.h"
+#include "lib/locking.h"
 #include "lib/timer.h"
 #include "lib/string.h"
 #include "nest/iface.h"
 #include "conf/conf.h"
 
 #include "sysdep/unix/unix.h"
+#include "sysdep/unix/io-loop.h"
 #include CONFIG_INCLUDE_SYSIO_H
 
 /* Maximum number of calls of tx handler for one socket in one
@@ -122,55 +124,50 @@ rf_fileno(struct rfile *f)
 
 btime boot_time;
 
+
 void
-times_init(struct timeloop *loop)
+times_update(void)
 {
   struct timespec ts;
   int rv;
 
+  btime old_time = current_time();
+  btime old_real_time = current_real_time();
+
   rv = clock_gettime(CLOCK_MONOTONIC, &ts);
   if (rv < 0)
     die("Monotonic clock is missing");
 
   if ((ts.tv_sec < 0) || (((u64) ts.tv_sec) > ((u64) 1 << 40)))
     log(L_WARN "Monotonic clock is crazy");
-
-  loop->last_time = ts.tv_sec S + ts.tv_nsec NS;
-  loop->real_time = 0;
-}
-
-void
-times_update(struct timeloop *loop)
-{
-  struct timespec ts;
-  int rv;
-
-  rv = clock_gettime(CLOCK_MONOTONIC, &ts);
-  if (rv < 0)
-    die("clock_gettime: %m");
-
+  
   btime new_time = ts.tv_sec S + ts.tv_nsec NS;
 
-  if (new_time < loop->last_time)
+  if (new_time < old_time)
     log(L_ERR "Monotonic clock is broken");
 
-  loop->last_time = new_time;
-  loop->real_time = 0;
-}
-
-void
-times_update_real_time(struct timeloop *loop)
-{
-  struct timespec ts;
-  int rv;
-
   rv = clock_gettime(CLOCK_REALTIME, &ts);
   if (rv < 0)
     die("clock_gettime: %m");
 
-  loop->real_time = ts.tv_sec S + ts.tv_nsec NS;
-}
+  btime new_real_time = ts.tv_sec S + ts.tv_nsec NS;
 
+  if (!atomic_compare_exchange_strong_explicit(
+      &last_time,
+      &old_time,
+      new_time,
+      memory_order_acq_rel,
+      memory_order_relaxed))
+    DBG("Time update collision: last_time");
+
+  if (!atomic_compare_exchange_strong_explicit(
+      &real_time,
+      &old_real_time,
+      new_real_time,
+      memory_order_acq_rel,
+      memory_order_relaxed))
+    DBG("Time update collision: real_time");
+}
 
 /**
  * DOC: Sockets
@@ -804,18 +801,16 @@ sk_free(resource *r)
     sk_ssh_free(s);
 #endif
 
-  if (s->fd < 0)
+  if ((s->fd < 0) || (s->flags & SKF_THREAD))
     return;
 
-  /* FIXME: we should call sk_stop() for SKF_THREAD sockets */
-  if (!(s->flags & SKF_THREAD))
-  {
-    if (s == current_sock)
-      current_sock = sk_next(s);
-    if (s == stored_sock)
-      stored_sock = sk_next(s);
+  if (s == current_sock)
+    current_sock = sk_next(s);
+  if (s == stored_sock)
+    stored_sock = sk_next(s);
+
+  if (enlisted(&s->n))
     rem_node(&s->n);
-  }
 
   if (s->type != SK_SSH && s->type != SK_SSH_ACTIVE)
     close(s->fd);
@@ -1108,7 +1103,11 @@ sk_passive_connected(sock *s, int type)
     return 1;
   }
 
-  sk_insert(t);
+  if (s->flags & SKF_PASSIVE_THREAD)
+    t->flags |= SKF_THREAD;
+  else
+    sk_insert(t);
+
   sk_alloc_bufs(t);
   s->rx_hook(t, 0);
   return 1;
@@ -1516,6 +1515,36 @@ sk_open_unix(sock *s, char *name)
   return 0;
 }
 
+static void
+sk_reloop_hook(void *_vs)
+{
+  sock *s = _vs;
+  if (birdloop_inside(&main_birdloop))
+  {
+    s->flags &= ~SKF_THREAD;
+    sk_insert(s);
+  }
+  else
+  {
+    s->flags |= SKF_THREAD;
+    sk_start(s);
+  }
+}
+
+void
+sk_reloop(sock *s, struct birdloop *loop)
+{
+  if (enlisted(&s->n))
+    rem_node(&s->n);
+
+  s->reloop = (event) {
+    .hook = sk_reloop_hook,
+    .data = s,
+  };
+
+  ev_send_loop(loop, &s->reloop);
+}
+
 
 #define CMSG_RX_SPACE MAX(CMSG4_SPACE_PKTINFO+CMSG4_SPACE_TTL, \
 			  CMSG6_SPACE_PKTINFO+CMSG6_SPACE_TTL)
@@ -2037,34 +2066,21 @@ struct event_log_entry
 static struct event_log_entry event_log[EVENT_LOG_LENGTH];
 static struct event_log_entry *event_open;
 static int event_log_pos, event_log_num, watchdog_active;
-static btime last_time;
+static btime last_io_time;
 static btime loop_time;
 
 static void
 io_update_time(void)
 {
-  struct timespec ts;
-  int rv;
-
-  /*
-   * This is third time-tracking procedure (after update_times() above and
-   * times_update() in BFD), dedicated to internal event log and latency
-   * tracking. Hopefully, we consolidate these sometimes.
-   */
-
-  rv = clock_gettime(CLOCK_MONOTONIC, &ts);
-  if (rv < 0)
-    die("clock_gettime: %m");
-
-  last_time = ts.tv_sec S + ts.tv_nsec NS;
+  last_io_time = current_time();
 
   if (event_open)
   {
-    event_open->duration = last_time - event_open->timestamp;
+    event_open->duration = last_io_time - event_open->timestamp;
 
     if (event_open->duration > config->latency_limit)
-      log(L_WARN "Event 0x%p 0x%p took %d ms",
-	  event_open->hook, event_open->data, (int) (event_open->duration TO_MS));
+      log(L_WARN "Event 0x%p 0x%p took %u.%03u ms",
+	  event_open->hook, event_open->data, (uint) (event_open->duration TO_MS), (uint) (event_open->duration % 1000));
 
     event_open = NULL;
   }
@@ -2089,7 +2105,7 @@ io_log_event(void *hook, void *data)
 
   en->hook = hook;
   en->data = data;
-  en->timestamp = last_time;
+  en->timestamp = last_io_time;
   en->duration = 0;
 
   event_log_num++;
@@ -2117,14 +2133,14 @@ io_log_dump(void)
     struct event_log_entry *en = event_log + (event_log_pos + i) % EVENT_LOG_LENGTH;
     if (en->hook)
       log(L_DEBUG "  Event 0x%p 0x%p at %8d for %d ms", en->hook, en->data,
-	  (int) ((last_time - en->timestamp) TO_MS), (int) (en->duration TO_MS));
+	  (int) ((last_io_time - en->timestamp) TO_MS), (int) (en->duration TO_MS));
   }
 }
 
 void
 watchdog_sigalrm(int sig UNUSED)
 {
-  /* Update last_time and duration, but skip latency check */
+  /* Update last_io_time and duration, but skip latency check */
   config->latency_limit = 0xffffffff;
   io_update_time();
 
@@ -2137,7 +2153,7 @@ watchdog_start1(void)
 {
   io_update_time();
 
-  loop_time = last_time;
+  loop_time = last_io_time;
 }
 
 static inline void
@@ -2145,7 +2161,7 @@ watchdog_start(void)
 {
   io_update_time();
 
-  loop_time = last_time;
+  loop_time = last_io_time;
   event_log_num = 0;
 
   if (config->watchdog_timeout)
@@ -2166,10 +2182,10 @@ watchdog_stop(void)
     watchdog_active = 0;
   }
 
-  btime duration = last_time - loop_time;
+  btime duration = last_io_time - loop_time;
   if (duration > config->watchdog_warning)
-    log(L_WARN "I/O loop cycle took %d ms for %d events",
-	(int) (duration TO_MS), event_log_num);
+    log(L_WARN "I/O loop cycle took %u.%03u ms for %d events",
+	(uint) (duration TO_MS), (uint) (duration % 1000), event_log_num);
 }
 
 
@@ -2181,8 +2197,9 @@ void
 io_init(void)
 {
   init_list(&sock_list);
-  init_list(&global_event_list);
-  init_list(&global_work_list);
+  ev_init_list(&global_event_list, &main_birdloop, "Global event list");
+  ev_init_list(&global_work_list, &main_birdloop, "Global work list");
+  ev_init_list(&main_birdloop.event_list, &main_birdloop, "Global fast event list");
   krt_io_init();
   // XXX init_times();
   // XXX update_times();
@@ -2196,6 +2213,8 @@ static int short_loops = 0;
 #define SHORT_LOOP_MAX 10
 #define WORK_EVENTS_MAX 10
 
+void pipe_drain(int fd);
+
 void
 io_loop(void)
 {
@@ -2210,22 +2229,28 @@ io_loop(void)
   watchdog_start1();
   for(;;)
     {
-      times_update(&main_timeloop);
+      times_update();
       events = ev_run_list(&global_event_list);
       events = ev_run_list_limited(&global_work_list, WORK_EVENTS_MAX) || events;
-      timers_fire(&main_timeloop);
+      events = ev_run_list(&main_birdloop.event_list) || events;
+      timers_fire(&main_birdloop.time, 1);
       io_close_event();
 
       // FIXME
       poll_tout = (events ? 0 : 3000); /* Time in milliseconds */
-      if (t = timers_first(&main_timeloop))
+      if (t = timers_first(&main_birdloop.time))
       {
-	times_update(&main_timeloop);
+	times_update();
 	timeout = (tm_remains(t) TO_MS) + 1;
 	poll_tout = MIN(poll_tout, timeout);
       }
 
-      nfds = 0;
+      /* A hack to reload main io_loop() when something has changed asynchronously. */
+      pfd[0].fd = main_birdloop.wakeup_fds[0];
+      pfd[0].events = POLLIN;
+
+      nfds = 1;
+
       WALK_LIST(n, sock_list)
 	{
 	  pfd[nfds] = (struct pollfd) { .fd = -1 }; /* everything other set to 0 by this */
@@ -2284,7 +2309,9 @@ io_loop(void)
 
       /* And finally enter poll() to find active sockets */
       watchdog_stop();
+      birdloop_leave(&main_birdloop);
       pout = poll(pfd, nfds, poll_tout);
+      birdloop_enter(&main_birdloop);
       watchdog_start();
 
       if (pout < 0)
@@ -2295,7 +2322,15 @@ io_loop(void)
 	}
       if (pout)
 	{
-	  times_update(&main_timeloop);
+	  if (pfd[0].revents & POLLIN)
+	  {
+	    /* IO loop reload requested */
+	    pipe_drain(main_birdloop.wakeup_fds[0]);
+	    atomic_exchange_explicit(&main_birdloop.ping_sent, 0, memory_order_acq_rel);
+	    continue;
+	  }
+
+	  times_update();
 
 	  /* guaranteed to be non-empty */
 	  current_sock = SKIP_BACK(sock, n, HEAD(sock_list));
diff --git a/sysdep/unix/krt.c b/sysdep/unix/krt.c
index 93d19614..dd2c63c4 100644
--- a/sysdep/unix/krt.c
+++ b/sysdep/unix/krt.c
@@ -681,9 +681,9 @@ krt_scan_timer_kick(struct krt_proto *p)
  */
 
 static int
-krt_preexport(struct channel *c, rte *e)
+krt_preexport(struct channel *C, rte *e)
 {
-  if (e->src->proto == c->proto)
+  if (e->src->proto == C->proto)
     return -1;
 
   if (!krt_capable(e))
diff --git a/sysdep/unix/log.c b/sysdep/unix/log.c
index 4e9df069..185231e8 100644
--- a/sysdep/unix/log.c
+++ b/sysdep/unix/log.c
@@ -15,6 +15,7 @@
  * user's manual.
  */
 
+#include <stdatomic.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <stdarg.h>
@@ -35,8 +36,10 @@ static FILE *dbgf;
 static list *current_log_list;
 static char *current_syslog_name; /* NULL -> syslog closed */
 
+static _Atomic uint max_thread_id = ATOMIC_VAR_INIT(1);
+static _Thread_local uint this_thread_id;
 
-#ifdef USE_PTHREADS
+#define THIS_THREAD_ID  (this_thread_id ?: (this_thread_id = atomic_fetch_add_explicit(&max_thread_id, 1, memory_order_acq_rel)))
 
 #include <pthread.h>
 
@@ -48,15 +51,6 @@ static pthread_t main_thread;
 void main_thread_init(void) { main_thread = pthread_self(); }
 static int main_thread_self(void) { return pthread_equal(pthread_self(), main_thread); }
 
-#else
-
-static inline void log_lock(void) {  }
-static inline void log_unlock(void) {  }
-void main_thread_init(void) { }
-static int main_thread_self(void) { return 1; }
-
-#endif
-
 
 #ifdef HAVE_SYSLOG_H
 #include <sys/syslog.h>
@@ -189,7 +183,7 @@ log_commit(int class, buffer *buf)
 		l->pos += msg_len;
 	      }
 
-	      fprintf(l->fh, "%s <%s> ", tbuf, class_names[class]);
+	      fprintf(l->fh, "%s [%04x] <%s> ", tbuf, THIS_THREAD_ID, class_names[class]);
 	    }
 	  fputs(buf->start, l->fh);
 	  fputc('\n', l->fh);
@@ -299,6 +293,8 @@ die(const char *msg, ...)
   exit(1);
 }
 
+static struct timespec dbg_time_start;
+
 /**
  * debug - write to debug output
  * @msg: a printf-like message
@@ -311,12 +307,33 @@ debug(const char *msg, ...)
 {
 #define MAX_DEBUG_BUFSIZE 16384
   va_list args;
-  char buf[MAX_DEBUG_BUFSIZE];
+  char buf[MAX_DEBUG_BUFSIZE], *pos = buf;
+  int max = MAX_DEBUG_BUFSIZE;
 
   va_start(args, msg);
   if (dbgf)
     {
-      if (bvsnprintf(buf, MAX_DEBUG_BUFSIZE, msg, args) < 0)
+      struct timespec dbg_time;
+      clock_gettime(CLOCK_MONOTONIC, &dbg_time);
+      uint nsec;
+      uint sec;
+
+      if (dbg_time.tv_nsec > dbg_time_start.tv_nsec)
+      {
+	nsec = dbg_time.tv_nsec - dbg_time_start.tv_nsec;
+	sec = dbg_time.tv_sec - dbg_time_start.tv_sec;
+      }
+      else
+      {
+	nsec = 1000000000 + dbg_time.tv_nsec - dbg_time_start.tv_nsec;
+	sec = dbg_time.tv_sec - dbg_time_start.tv_sec - 1;
+      }
+
+      int n = bsnprintf(pos, max, "%u.%09u: [%04x] ", sec, nsec, THIS_THREAD_ID);
+      pos += n;
+      max -= n;
+
+      if (bvsnprintf(pos, max, msg, args) < 0)
 	bug("Extremely long debug output, split it.");
 
       fputs(buf, dbgf);
@@ -422,6 +439,8 @@ done:
 void
 log_init_debug(char *f)
 {
+  clock_gettime(CLOCK_MONOTONIC, &dbg_time_start);
+
   if (dbgf && dbgf != stderr)
     fclose(dbgf);
   if (!f)
diff --git a/sysdep/unix/main.c b/sysdep/unix/main.c
index fd4934d9..bf9f2be0 100644
--- a/sysdep/unix/main.c
+++ b/sysdep/unix/main.c
@@ -28,6 +28,7 @@
 #include "lib/resource.h"
 #include "lib/socket.h"
 #include "lib/event.h"
+#include "lib/locking.h"
 #include "lib/timer.h"
 #include "lib/string.h"
 #include "nest/rt.h"
@@ -116,7 +117,7 @@ add_num_const(char *name, int val, const char *file, const uint line)
   struct f_val *v = cfg_alloc(sizeof(struct f_val));
   *v = (struct f_val) { .type = T_INT, .val.i = val };
   struct symbol *sym = cf_get_symbol(name);
-  if (sym->class && (sym->scope == conf_this_scope))
+  if (sym->class && cf_symbol_is_local(sym))
     cf_error("Error reading value for %s from %s:%d: already defined", name, file, line);
 
   cf_define_symbol(sym, SYM_CONSTANT | T_INT, val, v);
@@ -873,13 +874,16 @@ main(int argc, char **argv)
     dmalloc_debug(0x2f03d00);
 #endif
 
+  times_update();
   parse_args(argc, argv);
   log_switch(1, NULL, NULL);
 
+  the_bird_lock();
+
   random_init();
   net_init();
   resource_init();
-  timer_init();
+  birdloop_init();
   olock_init();
   rt_init();
   io_init();
@@ -927,6 +931,7 @@ main(int argc, char **argv)
       dup2(0, 2);
     }
 
+
   main_thread_init();
 
   write_pid_file();
diff --git a/test/birdtest.c b/test/birdtest.c
index ae05d1a5..5e3de1c5 100644
--- a/test/birdtest.c
+++ b/test/birdtest.c
@@ -21,6 +21,7 @@
 #include "test/birdtest.h"
 #include "lib/string.h"
 #include "lib/event.h"
+#include "lib/io-loop.h"
 
 #ifdef HAVE_EXECINFO_H
 #include <execinfo.h>
@@ -64,6 +65,9 @@ bt_init(int argc, char *argv[])
 {
   int c;
 
+  /* We have no interest in stdin */
+  close(0);
+
   initstate(BT_RANDOM_SEED, (char *) bt_random_state, sizeof(bt_random_state));
 
   bt_verbose = 0;
@@ -120,9 +124,11 @@ bt_init(int argc, char *argv[])
   clock_gettime(CLOCK_MONOTONIC, &bt_begin);
   bt_suite_case_begin = bt_suite_begin = bt_begin;
 
+  the_bird_lock();
   resource_init();
-  ev_init_list(&global_event_list);
-
+  ev_init_list(&global_event_list, &main_birdloop, "Global event list in unit tests");
+  ev_init_list(&global_work_list, &main_birdloop, "Global work list in unit tests");
+  birdloop_init();
   return;
 
  usage:
diff --git a/test/bt-utils.c b/test/bt-utils.c
index 509b5ed4..36e44da4 100644
--- a/test/bt-utils.c
+++ b/test/bt-utils.c
@@ -53,6 +53,8 @@ cf_file_read(byte *dest, uint max_len, int fd)
   return l;
 }
 
+void resource_sys_init(void);
+
 void
 bt_bird_init(void)
 {
@@ -61,7 +63,6 @@ bt_bird_init(void)
   log_switch(bt_verbose != 0, NULL, NULL);
 
   olock_init();
-  timer_init();
   rt_init();
   io_init();
   if_init();
@@ -73,6 +74,7 @@ bt_bird_init(void)
 void bt_bird_cleanup(void)
 {
   config = new_config = NULL;
+  the_bird_unlock();
 }
 
 static char *