| /* |
| * taskset.c - set or retrieve a task's CPU affinity |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License, version 2, as |
| * published by the Free Software Foundation |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License along |
| * with this program; if not, write to the Free Software Foundation, Inc., |
| * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Copyright (C) 2004 Robert Love |
| * Copyright (C) 2010 Karel Zak <kzak@redhat.com> |
| */ |
| |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <unistd.h> |
| #include <getopt.h> |
| #include <errno.h> |
| #include <sched.h> |
| #include <stddef.h> |
| #include <string.h> |
| |
| #include "cpuset.h" |
| #include "nls.h" |
| #include "strutils.h" |
| #include "xalloc.h" |
| #include "procutils.h" |
| #include "c.h" |
| #include "closestream.h" |
| |
| struct taskset { |
| pid_t pid; /* task PID */ |
| cpu_set_t *set; /* task CPU mask */ |
| size_t setsize; |
| char *buf; /* buffer for conversion from mask to string */ |
| size_t buflen; |
| unsigned int use_list:1, /* use list rather than masks */ |
| get_only:1; /* print the mask, but not modify */ |
| }; |
| |
| static void __attribute__((__noreturn__)) usage(void) |
| { |
| FILE *out = stdout; |
| fprintf(out, |
| _("Usage: %s [options] [mask | cpu-list] [pid|cmd [args...]]\n\n"), |
| program_invocation_short_name); |
| |
| fputs(USAGE_SEPARATOR, out); |
| fputs(_("Show or change the CPU affinity of a process.\n"), out); |
| fputs(USAGE_SEPARATOR, out); |
| |
| fprintf(out, _( |
| "Options:\n" |
| " -a, --all-tasks operate on all the tasks (threads) for a given pid\n" |
| " -p, --pid operate on existing given pid\n" |
| " -c, --cpu-list display and specify cpus in list format\n" |
| )); |
| printf(USAGE_HELP_OPTIONS(25)); |
| |
| fputs(USAGE_SEPARATOR, out); |
| fprintf(out, _( |
| "The default behavior is to run a new command:\n" |
| " %1$s 03 sshd -b 1024\n" |
| "You can retrieve the mask of an existing task:\n" |
| " %1$s -p 700\n" |
| "Or set it:\n" |
| " %1$s -p 03 700\n" |
| "List format uses a comma-separated list instead of a mask:\n" |
| " %1$s -pc 0,3,7-11 700\n" |
| "Ranges in list format can take a stride argument:\n" |
| " e.g. 0-31:2 is equivalent to mask 0x55555555\n"), |
| program_invocation_short_name); |
| |
| printf(USAGE_MAN_TAIL("taskset(1)")); |
| exit(EXIT_SUCCESS); |
| } |
| |
| static void print_affinity(struct taskset *ts, int isnew) |
| { |
| char *str, *msg; |
| |
| if (ts->use_list) { |
| str = cpulist_create(ts->buf, ts->buflen, ts->set, ts->setsize); |
| msg = isnew ? _("pid %d's new affinity list: %s\n") : |
| _("pid %d's current affinity list: %s\n"); |
| } else { |
| str = cpumask_create(ts->buf, ts->buflen, ts->set, ts->setsize); |
| msg = isnew ? _("pid %d's new affinity mask: %s\n") : |
| _("pid %d's current affinity mask: %s\n"); |
| } |
| |
| if (!str) |
| errx(EXIT_FAILURE, _("internal error: conversion from cpuset to string failed")); |
| |
| printf(msg, ts->pid ? ts->pid : getpid(), str); |
| } |
| |
| static void __attribute__((__noreturn__)) err_affinity(pid_t pid, int set) |
| { |
| char *msg; |
| |
| msg = set ? _("failed to set pid %d's affinity") : |
| _("failed to get pid %d's affinity"); |
| |
| err(EXIT_FAILURE, msg, pid ? pid : getpid()); |
| } |
| |
| static void do_taskset(struct taskset *ts, size_t setsize, cpu_set_t *set) |
| { |
| /* read the current mask */ |
| if (ts->pid) { |
| if (sched_getaffinity(ts->pid, ts->setsize, ts->set) < 0) |
| err_affinity(ts->pid, 1); |
| print_affinity(ts, FALSE); |
| } |
| |
| if (ts->get_only) |
| return; |
| |
| /* set new mask */ |
| if (sched_setaffinity(ts->pid, setsize, set) < 0) |
| err_affinity(ts->pid, 1); |
| |
| /* re-read the current mask */ |
| if (ts->pid) { |
| if (sched_getaffinity(ts->pid, ts->setsize, ts->set) < 0) |
| err_affinity(ts->pid, 0); |
| print_affinity(ts, TRUE); |
| } |
| } |
| |
| int main(int argc, char **argv) |
| { |
| cpu_set_t *new_set; |
| pid_t pid = 0; |
| int c, all_tasks = 0; |
| int ncpus; |
| size_t new_setsize, nbits; |
| struct taskset ts; |
| |
| static const struct option longopts[] = { |
| { "all-tasks", 0, NULL, 'a' }, |
| { "pid", 0, NULL, 'p' }, |
| { "cpu-list", 0, NULL, 'c' }, |
| { "help", 0, NULL, 'h' }, |
| { "version", 0, NULL, 'V' }, |
| { NULL, 0, NULL, 0 } |
| }; |
| |
| setlocale(LC_ALL, ""); |
| bindtextdomain(PACKAGE, LOCALEDIR); |
| textdomain(PACKAGE); |
| atexit(close_stdout); |
| |
| memset(&ts, 0, sizeof(ts)); |
| |
| while ((c = getopt_long(argc, argv, "+apchV", longopts, NULL)) != -1) { |
| switch (c) { |
| case 'a': |
| all_tasks = 1; |
| break; |
| case 'p': |
| pid = strtos32_or_err(argv[argc - 1], |
| _("invalid PID argument")); |
| break; |
| case 'c': |
| ts.use_list = 1; |
| break; |
| case 'V': |
| printf(UTIL_LINUX_VERSION); |
| return EXIT_SUCCESS; |
| case 'h': |
| usage(); |
| break; |
| default: |
| errtryhelp(EXIT_FAILURE); |
| } |
| } |
| |
| if ((!pid && argc - optind < 2) |
| || (pid && (argc - optind < 1 || argc - optind > 2))) { |
| warnx(_("bad usage")); |
| errtryhelp(EXIT_FAILURE); |
| } |
| |
| ncpus = get_max_number_of_cpus(); |
| if (ncpus <= 0) |
| errx(EXIT_FAILURE, _("cannot determine NR_CPUS; aborting")); |
| |
| /* |
| * the ts->set is always used for the sched_getaffinity call |
| * On the sched_getaffinity the kernel demands a user mask of |
| * at least the size of its own cpumask_t. |
| */ |
| ts.set = cpuset_alloc(ncpus, &ts.setsize, &nbits); |
| if (!ts.set) |
| err(EXIT_FAILURE, _("cpuset_alloc failed")); |
| |
| /* buffer for conversion from mask to string */ |
| ts.buflen = 7 * nbits; |
| ts.buf = xmalloc(ts.buflen); |
| |
| /* |
| * new_set is always used for the sched_setaffinity call |
| * On the sched_setaffinity the kernel will zero-fill its |
| * cpumask_t if the user's mask is shorter. |
| */ |
| new_set = cpuset_alloc(ncpus, &new_setsize, NULL); |
| if (!new_set) |
| err(EXIT_FAILURE, _("cpuset_alloc failed")); |
| |
| if (argc - optind == 1) |
| ts.get_only = 1; |
| |
| else if (ts.use_list) { |
| if (cpulist_parse(argv[optind], new_set, new_setsize, 0)) |
| errx(EXIT_FAILURE, _("failed to parse CPU list: %s"), |
| argv[optind]); |
| } else if (cpumask_parse(argv[optind], new_set, new_setsize)) { |
| errx(EXIT_FAILURE, _("failed to parse CPU mask: %s"), |
| argv[optind]); |
| } |
| |
| if (all_tasks && pid) { |
| struct proc_tasks *tasks = proc_open_tasks(pid); |
| while (!proc_next_tid(tasks, &ts.pid)) |
| do_taskset(&ts, new_setsize, new_set); |
| proc_close_tasks(tasks); |
| } else { |
| ts.pid = pid; |
| do_taskset(&ts, new_setsize, new_set); |
| } |
| |
| free(ts.buf); |
| cpuset_free(ts.set); |
| cpuset_free(new_set); |
| |
| if (!pid) { |
| argv += optind + 1; |
| execvp(argv[0], argv); |
| errexec(argv[0]); |
| } |
| |
| return EXIT_SUCCESS; |
| } |