Converting the former BFD loop to a universal IO loop and protocol loop.

There is a simple universal IO loop, taking care of events, timers and
sockets. Primarily, one instance of a protocol should use exactly one IO
loop to do all its work, as is now done in BFD.

Contrary to previous versions, the loop is now launched and cleaned by
the nest/proto.c code, allowing for a protocol to just request its own
loop by setting the loop's lock order in config higher than the_bird.

It is not supported nor checked if any protocol changed the requested
lock order in reconfigure. No protocol should do it at all.

1 files changed, 35 insertions, 6 deletions

diff --git a/lib/event.h b/lib/event.h
index 5f3b78d8..6c358f84 100644
--- a/lib/event.h
+++ b/lib/event.h
@@ -10,33 +10,62 @@
 #define _BIRD_EVENT_H_
 
 #include "lib/resource.h"
+#include "lib/locking.h"
+
+#include <stdatomic.h>
+
+DEFINE_DOMAIN(event);
 
 typedef struct event {
   resource r;
   void (*hook)(void *);
   void *data;
   node n;				/* Internal link */
+  struct event_list *list;		/* List where this event is put in */
 } event;
 
-typedef list event_list;
+typedef struct event_list {
+  list events;
+  pool *pool;
+  struct birdloop *loop;
+  DOMAIN(event) lock;
+} 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_enqueue(event_list *, event *);
-void ev_schedule(event *);
-void ev_schedule_work(event *);
+
+static inline void ev_init_list(event_list *el, struct birdloop *loop, const char *name)
+{
+  init_list(&el->events);
+  el->loop = loop;
+  el->lock = DOMAIN_NEW(event, name);
+}
+
+void ev_send(event_list *, event *);
+#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 LEGACY_EVENT_LIST(l)  (((l) == &global_event_list) || ((l) == &global_work_list))
+
+_Bool birdloop_inside(struct birdloop *loop);
+
 static inline int
 ev_active(event *e)
 {
-  return e->n.next != NULL;
+  if (e->list == NULL)
+    return 0;
+
+  ASSERT_DIE(birdloop_inside(e->list->loop));
+  return enlisted(&e->n);
 }
 
 static inline event*