From 25128176c46b169cdec2c18b5730c36a940f6eb0 Mon Sep 17 00:00:00 2001 From: Denys Vlasenko Date: Sat, 19 Jun 2021 17:42:35 +0200 Subject: [PATCH] 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 --- util-linux/taskset.c | 110 +++++++++++++++++++++++++++---------------- 1 file changed, 70 insertions(+), 40 deletions(-) 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 ...rest.is.ignored..." */ - pid_str = *argv; /* NB: *argv != NULL in this case */ - } - /* else it was just "-p ", and *argv == NULL */ - pid = xatoul_range(pid_str, 1, ((unsigned)(pid_t)ULONG_MAX) >> 1); - } else { - /* */ - 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 ", * or it was "-p " 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 [...ignored...]" */ + if ((opts & OPT_p) && aff) { /* "-p [...ignored...]" */ + aff = NULL; goto print_aff; /* print new affinity and exit */ - - BB_EXECVP_or_die(argv); + } +} + +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; + + aff = *argv++; + if (!(opts & OPT_p)) { + /* */ + if (!*argv) + bb_show_usage(); + process_pid_str("0", opts, aff); + BB_EXECVP_or_die(argv); + } + + pid_str = aff; + if (*argv) /* "-p ...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; }