From 71bc71a7dc2601b1d9beb73ee1f178da1733788e Mon Sep 17 00:00:00 2001 From: Bernhard Reutner-Fischer Date: Fri, 9 Mar 2007 16:56:38 +0000 Subject: - add chrt applet. text data bss dec hex filename 769 0 0 769 301 miscutils/chrt.o and could use some further shrinkage --- miscutils/chrt.c | 124 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 124 insertions(+) create mode 100644 miscutils/chrt.c (limited to 'miscutils/chrt.c') diff --git a/miscutils/chrt.c b/miscutils/chrt.c new file mode 100644 index 000000000..75d77d536 --- /dev/null +++ b/miscutils/chrt.c @@ -0,0 +1,124 @@ +/* vi: set sw=4 ts=4: */ +/* + * chrt - manipulate real-time attributes of a process + * Copyright (c) 2006-2007 Bernhard Fischer + * + * Licensed under GPLv2 or later, see file LICENSE in this tarball for details. + */ + +#include "busybox.h" +#include +#include +#include /* optind */ +#ifndef _POSIX_PRIORITY_SCHEDULING +#warning your system may be foobared +#endif +static const struct { + const int policy; + const char const name[12]; +} policies[] = { + {SCHED_OTHER, "SCHED_OTHER"}, + {SCHED_FIFO, "SCHED_FIFO"}, + {SCHED_RR, "SCHED_RR"} +}; + +static void show_min_max(int pol) { + const char *fmt = "%s min/max priority\t: %d/%d\n\0%s not supported?\n"; + int max, min; + max = sched_get_priority_max(pol); + min = sched_get_priority_min(pol); + if (max >= 0 && min >= 0) + printf(fmt, policies[pol].name, min, max); + else { + fmt += 29; + printf(fmt, policies[pol].name); + } +} + +#define OPT_m (1<<0) +#define OPT_p (1<<1) +#define OPT_r (1<<2) +#define OPT_f (1<<3) +#define OPT_o (1<<4) + +int chrt_main(int argc, char** argv); +int chrt_main(int argc, char** argv) +{ + pid_t pid = 0; + unsigned opt; + struct sched_param sp; + char *p_opt = NULL, *priority = NULL; + const char *state = "current\0new"; + int prio = 0, policy = SCHED_RR; + + opt_complementary = "r--fo:f--ro:r--fo"; /* only one policy accepted */ + opt = getopt32(argc, argv, "+mp:rfo", &p_opt); + if (opt & OPT_r) + policy = SCHED_RR; + if (opt & OPT_f) + policy = SCHED_FIFO; + if (opt & OPT_o) + policy = SCHED_OTHER; + + if (opt & OPT_m) { /* print min/max */ + show_min_max(SCHED_FIFO); + show_min_max(SCHED_RR); + show_min_max(SCHED_OTHER); + fflush_stdout_and_exit(EXIT_SUCCESS); + } + if (opt & OPT_p) { + if (argc == optind+1) { /* -p */ + priority = p_opt; + p_opt = argv[optind]; + } + argv += optind; /* me -p */ + pid = xatoul_range(p_opt, 1, ULONG_MAX); /* -p */ + } else { + argv += optind; /* me -p */ + priority = *argv; + } + if (priority) { + /* from the manpage of sched_getscheduler: + [...] sched_priority can have a value + in the range 0 to 99. + [...] SCHED_OTHER or SCHED_BATCH must be assigned + the static priority 0. [...] SCHED_FIFO or + SCHED_RR can have a static priority in the range 1 to 99. + */ + prio = xstrtol_range(priority, 0, policy == SCHED_OTHER + ? 0 : 1, 99); + } + + if (opt & OPT_p) { + int pol = 0; +print_rt_info: + pol = sched_getscheduler(pid); + if (pol < 0) + bb_perror_msg_and_die("failed to %cet pid %d's policy", 'g', pid); + printf("pid %d's %s scheduling policy: %s\n", + pid, state, policies[pol].name); + if (sched_getparam(pid, &sp)) + bb_perror_msg_and_die("failed to get pid %d's attributes", pid); + printf("pid %d's %s scheduling priority: %d\n", + pid, state, sp.sched_priority); + if (!*argv) /* no new prio given or we did print already, done. */ + return EXIT_SUCCESS; + } + + sp.sched_priority = prio; + if (sched_setscheduler(pid, policy, &sp) < 0) + bb_perror_msg_and_die("failed to %cet pid %d's policy", 's', pid); + if (opt & OPT_p) { + state += 8; + ++argv; + goto print_rt_info; + } + ++argv; + BB_EXECVP(*argv, argv); + bb_perror_msg_and_die("%s", *argv); +} +#undef OPT_p +#undef OPT_r +#undef OPT_f +#undef OPT_o +#undef OPT_m -- cgit v1.2.3