| Bernhard Reutner-Fischer | 32eddff | 2006-11-22 16:39:48 +0000 | [diff] [blame] | 1 | /* vi: set sw=4 ts=4: */ |
| 2 | /* |
| 3 | * taskset - retrieve or set a processes' CPU affinity |
| 4 | * Copyright (c) 2006 Bernhard Fischer |
| 5 | * |
| 6 | * Licensed under GPLv2 or later, see file LICENSE in this tarball for details. |
| 7 | */ |
| 8 | |
| 9 | #include "busybox.h" |
| 10 | #include <sched.h> |
| 11 | #include <unistd.h> |
| 12 | #include <getopt.h> /* optind */ |
| 13 | |
| 14 | #if ENABLE_FEATURE_TASKSET_FANCY |
| 15 | #define TASKSET_PRINTF_MASK "%s" |
| 16 | #define from_cpuset(x) __from_cpuset(&x) |
| 17 | /* craft a string from the mask */ |
| 18 | static char *__from_cpuset(cpu_set_t *mask) { |
| 19 | int i; |
| 20 | char *ret = 0, *str = xzalloc(9); |
| 21 | |
| 22 | for (i = CPU_SETSIZE - 4; i >= 0; i -= 4) { |
| 23 | char val = 0; |
| 24 | int off; |
| 25 | for (off = 0; off <= 3; ++off) |
| 26 | if (CPU_ISSET(i+off, mask)) |
| 27 | val |= 1<<off; |
| 28 | |
| 29 | if (!ret && val) |
| 30 | ret = str; |
| 31 | *str++ = (val-'0'<=9) ? (val+48) : (val+87); |
| 32 | } |
| 33 | return ret; |
| 34 | } |
| 35 | #else |
| 36 | #define TASKSET_PRINTF_MASK "%x" |
| 37 | #define from_cpuset(mask) mask |
| 38 | #endif |
| 39 | |
| 40 | #define TASKSET_OPT_p (1) |
| 41 | |
| 42 | int taskset_main(int argc, char** argv) |
| 43 | { |
| 44 | cpu_set_t mask, new_mask; |
| 45 | pid_t pid = 0; |
| 46 | unsigned long ul; |
| 47 | const char *state = "current\0new"; |
| 48 | char *p_opt = NULL, *aff = NULL; |
| 49 | |
| 50 | ul = getopt32(argc, argv, "+p:", &p_opt); |
| 51 | |
| 52 | if (ul & TASKSET_OPT_p) { |
| 53 | if (argc == optind+1) { /* -p <aff> <pid> */ |
| 54 | aff = p_opt; |
| 55 | p_opt = argv[optind]; |
| 56 | } |
| 57 | argv += optind; /* me -p <arg> */ |
| 58 | pid = xatoul_range(p_opt, 1, ULONG_MAX); /* -p <pid> */ |
| 59 | } else |
| 60 | aff = *++argv; /* <aff> <cmd...> */ |
| 61 | if (aff) { |
| 62 | unsigned i = 0; |
| 63 | unsigned long l = xstrtol_range(aff, 16, 1, ULONG_MAX); |
| 64 | |
| 65 | CPU_ZERO(&new_mask); |
| 66 | while (i < CPU_SETSIZE && l >= (1<<i)) { |
| 67 | if ((1<<i) & l) |
| 68 | CPU_SET(i, &new_mask); |
| 69 | ++i; |
| 70 | } |
| 71 | } |
| 72 | |
| 73 | if (ul & TASKSET_OPT_p) { |
| 74 | print_aff: |
| 75 | if (sched_getaffinity(pid, sizeof (mask), &mask) < 0) |
| 76 | bb_perror_msg_and_die("Failed to %cet pid %d's affinity", 'g', pid); |
| 77 | printf("pid %d's %s affinity mask: "TASKSET_PRINTF_MASK"\n", |
| 78 | pid, state, from_cpuset(mask)); |
| 79 | if (!*argv) /* no new affinity given or we did print already, done. */ |
| 80 | return EXIT_SUCCESS; |
| 81 | } |
| 82 | |
| 83 | if (sched_setaffinity(pid, sizeof (new_mask), &new_mask)) |
| 84 | bb_perror_msg_and_die("Failed to %cet pid %d's affinity", 's', pid); |
| 85 | if (ul & TASKSET_OPT_p) { |
| 86 | state += 8; |
| 87 | ++argv; |
| 88 | goto print_aff; |
| 89 | } |
| 90 | ++argv; |
| 91 | execvp(*argv, argv); |
| 92 | bb_perror_msg_and_die("%s", *argv); |
| 93 | } |
| 94 | #undef TASKSET_OPT_p |
| 95 | #undef TASKSET_PRINTF_MASK |
| 96 | #undef from_cpuset |