From 25128176c46b169cdec2c18b5730c36a940f6eb0 Mon Sep 17 00:00:00 2001
From: Denys Vlasenko <vda.linux@googlemail.com>
Date: Sat, 19 Jun 2021 17:42:35 +0200
Subject: taskset: implement -a
function old new delta
process_pid_str - 854 +854
.rodata 103363 103378 +15
packed_usage 33654 33658 +4
taskset_main 936 190 -746
------------------------------------------------------------------------------
(add/remove: 1/0 grow/shrink: 2/1 up/down: 873/-746) Total: 127 bytes
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
---
util-linux/taskset.c | 108 ++++++++++++++++++++++++++++++++-------------------
1 file changed, 69 insertions(+), 39 deletions(-)
(limited to 'util-linux')
diff --git a/util-linux/taskset.c b/util-linux/taskset.c
index b542f8c83..abec04933 100644
--- a/util-linux/taskset.c
+++ b/util-linux/taskset.c
@@ -34,10 +34,12 @@
//kbuild:lib-$(CONFIG_TASKSET) += taskset.o
//usage:#define taskset_trivial_usage
-//usage: "[-p] [HEXMASK] PID | PROG ARGS"
+//usage: "[-ap] [HEXMASK"IF_FEATURE_TASKSET_CPULIST(" | -c LIST")"] { PID | PROG ARGS }"
//usage:#define taskset_full_usage "\n\n"
//usage: "Set or get CPU affinity\n"
-//usage: "\n -p Operate on an existing PID"
+//usage: "\n -p Operate on PID"
+//usage: "\n -a Operate on all threads"
+//usage: "\n -c Affinity is a list, not mask"
//usage:
//usage:#define taskset_example_usage
//usage: "$ taskset 0x7 ./dgemm_test&\n"
@@ -205,42 +207,18 @@ static void print_cpulist(const ul *mask, unsigned mask_size_in_bytes)
}
#endif
-int taskset_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
-int taskset_main(int argc UNUSED_PARAM, char **argv)
+enum {
+ OPT_p = 1 << 0,
+ OPT_a = 1 << 1,
+ OPT_c = (1 << 2) * ENABLE_FEATURE_TASKSET_CPULIST,
+};
+
+static void process_pid_str(const char *pid_str, unsigned opts, char *aff)
{
ul *mask;
unsigned mask_size_in_bytes;
- pid_t pid = 0;
const char *current_new;
- char *aff;
- unsigned opts;
- enum {
- OPT_p = 1 << 0,
- OPT_c = (1 << 1) * ENABLE_FEATURE_TASKSET_CPULIST,
- };
-
- /* NB: we mimic util-linux's taskset: -p does not take
- * an argument, i.e., "-pN" is NOT valid, only "-p N"!
- * Indeed, util-linux-2.13-pre7 uses:
- * getopt_long(argc, argv, "+pchV", ...), not "...p:..." */
-
- opts = getopt32(argv, "^+" "p"IF_FEATURE_TASKSET_CPULIST("c")
- "\0" "-1" /* at least 1 arg */);
- argv += optind;
-
- aff = *argv++;
- if (opts & OPT_p) {
- char *pid_str = aff;
- if (*argv) { /* "-p <aff> <pid> ...rest.is.ignored..." */
- pid_str = *argv; /* NB: *argv != NULL in this case */
- }
- /* else it was just "-p <pid>", and *argv == NULL */
- pid = xatoul_range(pid_str, 1, ((unsigned)(pid_t)ULONG_MAX) >> 1);
- } else {
- /* <aff> <cmd...> */
- if (!*argv)
- bb_show_usage();
- }
+ pid_t pid = xatoi_positive(pid_str);
mask_size_in_bytes = SZOF_UL;
current_new = "current";
@@ -255,13 +233,12 @@ int taskset_main(int argc UNUSED_PARAM, char **argv)
#endif
printf("pid %d's %s affinity mask: "TASKSET_PRINTF_MASK"\n",
pid, current_new, from_mask(mask, mask_size_in_bytes));
- if (*argv == NULL) {
+ if (!aff) {
/* Either it was just "-p <pid>",
* or it was "-p <aff> <pid>" and we came here
* for the second time (see goto below) */
- return EXIT_SUCCESS;
+ return;
}
- *argv = NULL;
current_new = "new";
}
memset(mask, 0, mask_size_in_bytes);
@@ -331,8 +308,61 @@ int taskset_main(int argc UNUSED_PARAM, char **argv)
bb_perror_msg_and_die("can't %cet pid %d's affinity", 's', pid);
//bb_error_msg("set mask[0]:%lx", mask[0]);
- if (!argv[0]) /* "-p <aff> <pid> [...ignored...]" */
+ if ((opts & OPT_p) && aff) { /* "-p <aff> <pid> [...ignored...]" */
+ aff = NULL;
goto print_aff; /* print new affinity and exit */
+ }
+}
+
+int taskset_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
+int taskset_main(int argc UNUSED_PARAM, char **argv)
+{
+ const char *pid_str;
+ char *aff;
+ unsigned opts;
+
+ /* NB: we mimic util-linux's taskset: -p does not take
+ * an argument, i.e., "-pN" is NOT valid, only "-p N"!
+ * Indeed, util-linux-2.13-pre7 uses:
+ * getopt_long(argc, argv, "+pchV", ...), not "...p:..." */
+
+ opts = getopt32(argv, "^+" "pa"IF_FEATURE_TASKSET_CPULIST("c")
+ "\0" "-1" /* at least 1 arg */);
+ argv += optind;
- BB_EXECVP_or_die(argv);
+ aff = *argv++;
+ if (!(opts & OPT_p)) {
+ /* <aff> <cmd...> */
+ if (!*argv)
+ bb_show_usage();
+ process_pid_str("0", opts, aff);
+ BB_EXECVP_or_die(argv);
+ }
+
+ pid_str = aff;
+ if (*argv) /* "-p <aff> <pid> ...rest.is.ignored..." */
+ pid_str = *argv; /* NB: *argv != NULL in this case */
+ else
+ aff = NULL;
+
+ if (opts & OPT_a) {
+ char dn[sizeof("/proc/%s/task") + 3 * sizeof(int)];
+ DIR *dir;
+ struct dirent *ent;
+
+ sprintf(dn, "/proc/%s/task", pid_str);
+ dir = opendir(dn);
+ if (!dir) {
+ goto no_threads;
+ }
+ while ((ent = readdir(dir)) != NULL) {
+ if (isdigit(ent->d_name[0]))
+ process_pid_str(ent->d_name, opts, aff);
+ }
+ IF_FEATURE_CLEAN_UP(closedir(dir);)
+ } else {
+ no_threads:
+ process_pid_str(pid_str, opts, aff);
+ }
+ return EXIT_SUCCESS;
}
--
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