Imported Upstream version 2.22upstream/2.22upstream

1 files changed, 339 insertions, 0 deletions

diff --git a/schedutils/chrt.c b/schedutils/chrt.c
new file mode 100644
index 0000000..95a6adc
--- /dev/null
+++ b/schedutils/chrt.c
@@ -0,0 +1,339 @@
+/*
+ * chrt.c - chrt
+ * Command-line utility for manipulating a task's real-time attributes 
+ *
+ * Robert Love <rml@tech9.net>
+ * 27-Apr-2002: initial version
+ * 04-May-2011: make thread aware - Davidlohr Bueso <dave@gnu.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, v2, 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
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <sched.h>
+#include <unistd.h>
+#include <getopt.h>
+#include <errno.h>
+
+#include "c.h"
+#include "nls.h"
+#include "closestream.h"
+#include "strutils.h"
+#include "procutils.h"
+
+/* the SCHED_BATCH is supported since Linux 2.6.16
+ *  -- temporary workaround for people with old glibc headers
+ */
+#if defined (__linux__) && !defined(SCHED_BATCH)
+# define SCHED_BATCH 3
+#endif
+
+/* the SCHED_IDLE is supported since Linux 2.6.23
+ * commit id 0e6aca43e08a62a48d6770e9a159dbec167bf4c6
+ * -- temporary workaround for people with old glibc headers
+ */
+#if defined (__linux__) && !defined(SCHED_IDLE)
+# define SCHED_IDLE 5
+#endif
+
+#if defined(__linux__) && !defined(SCHED_RESET_ON_FORK)
+#define SCHED_RESET_ON_FORK 0x40000000
+#endif
+
+
+static void __attribute__((__noreturn__)) show_usage(int rc)
+{
+	FILE *out = rc == EXIT_SUCCESS ? stdout : stderr;
+
+	fprintf(out, _(
+	"\nchrt - manipulate real-time attributes of a process\n"
+	"\nSet policy:\n"
+	"  chrt [options] <policy> <priority> {<pid> | <command> [<arg> ...]}\n"
+	"\nGet policy:\n"
+	"  chrt [options] {<pid> | <command> [<arg> ...]}\n"));
+
+	fprintf(out, _(
+	"\nScheduling policies:\n"
+	"  -b | --batch         set policy to SCHED_BATCH\n"
+	"  -f | --fifo          set policy to SCHED_FIFO\n"
+	"  -i | --idle          set policy to SCHED_IDLE\n"
+	"  -o | --other         set policy to SCHED_OTHER\n"
+	"  -r | --rr            set policy to SCHED_RR (default)\n"));
+
+#ifdef SCHED_RESET_ON_FORK
+	fprintf(out, _(
+	"\nScheduling flags:\n"
+	"  -R | --reset-on-fork set SCHED_RESET_ON_FORK for FIFO or RR\n"));
+#endif
+	fprintf(out, _(
+	"\nOptions:\n"
+	"  -a | --all-tasks     operate on all the tasks (threads) for a given pid\n"
+	"  -h | --help          display this help\n"
+	"  -m | --max           show min and max valid priorities\n"
+	"  -p | --pid           operate on existing given pid\n"
+	"  -v | --verbose       display status information\n"
+	"  -V | --version       output version information\n\n"));
+
+	exit(rc);
+}
+
+static void show_rt_info(pid_t pid, int isnew)
+{
+	struct sched_param sp;
+	int policy;
+
+	/* don't display "pid 0" as that is confusing */
+	if (!pid)
+		pid = getpid();
+
+	policy = sched_getscheduler(pid);
+	if (policy == -1)
+		err(EXIT_FAILURE, _("failed to get pid %d's policy"), pid);
+
+	if (isnew)
+		printf(_("pid %d's new scheduling policy: "), pid);
+	else
+		printf(_("pid %d's current scheduling policy: "), pid);
+
+	switch (policy) {
+	case SCHED_OTHER:
+		printf("SCHED_OTHER\n");
+		break;
+	case SCHED_FIFO:
+		printf("SCHED_FIFO\n");
+		break;
+#ifdef SCHED_RESET_ON_FORK
+	case SCHED_FIFO | SCHED_RESET_ON_FORK:
+		printf("SCHED_FIFO|SCHED_RESET_ON_FORK\n");
+		break;
+#endif
+#ifdef SCHED_IDLE
+	case SCHED_IDLE:
+		printf("SCHED_IDLE\n");
+		break;
+#endif
+	case SCHED_RR:
+		printf("SCHED_RR\n");
+		break;
+#ifdef SCHED_RESET_ON_FORK
+	case SCHED_RR | SCHED_RESET_ON_FORK:
+		printf("SCHED_RR|SCHED_RESET_ON_FORK\n");
+		break;
+#endif
+#ifdef SCHED_BATCH
+	case SCHED_BATCH:
+		printf("SCHED_BATCH\n");
+		break;
+#endif
+	default:
+		warnx(_("unknown scheduling policy"));
+	}
+
+	if (sched_getparam(pid, &sp))
+		err(EXIT_FAILURE, _("failed to get pid %d's attributes"), pid);
+
+	if (isnew)
+		printf(_("pid %d's new scheduling priority: %d\n"),
+		       pid, sp.sched_priority);
+	else
+		printf(_("pid %d's current scheduling priority: %d\n"),
+		       pid, sp.sched_priority);
+}
+
+static void show_min_max(void)
+{
+	unsigned long i;
+	int policies[] = {
+		SCHED_OTHER,
+		SCHED_FIFO,
+		SCHED_RR,
+#ifdef SCHED_BATCH
+		SCHED_BATCH,
+#endif
+#ifdef SCHED_IDLE
+		SCHED_IDLE,
+#endif
+	};
+	const char *names[] = {
+		"OTHER",
+		"FIFO",
+		"RR",
+#ifdef SCHED_BATCH
+		"BATCH",
+#endif
+#ifdef SCHED_IDLE
+		"IDLE",
+#endif
+	};
+
+	for (i = 0; i < ARRAY_SIZE(policies); i++) {
+		int max = sched_get_priority_max(policies[i]);
+		int min = sched_get_priority_min(policies[i]);
+
+		if (max >= 0 && min >= 0)
+			printf(_("SCHED_%s min/max priority\t: %d/%d\n"),
+					names[i], min, max);
+		else
+			printf(_("SCHED_%s not supported?\n"), names[i]);
+	}
+}
+
+int main(int argc, char **argv)
+{
+	int i, policy = SCHED_RR, priority = 0, verbose = 0, policy_flag = 0,
+	    all_tasks = 0;
+	struct sched_param sp;
+	pid_t pid = -1;
+
+	static const struct option longopts[] = {
+		{ "all-tasks",  0, NULL, 'a' },
+		{ "batch",	0, NULL, 'b' },
+		{ "fifo",	0, NULL, 'f' },
+		{ "idle",	0, NULL, 'i' },
+		{ "pid",	0, NULL, 'p' },
+		{ "help",	0, NULL, 'h' },
+		{ "max",        0, NULL, 'm' },
+		{ "other",	0, NULL, 'o' },
+		{ "rr",		0, NULL, 'r' },
+		{ "reset-on-fork", 0, NULL, 'R' },
+		{ "verbose",	0, NULL, 'v' },
+		{ "version",	0, NULL, 'V' },
+		{ NULL,		0, NULL, 0 }
+	};
+
+	setlocale(LC_ALL, "");
+	bindtextdomain(PACKAGE, LOCALEDIR);
+	textdomain(PACKAGE);
+	atexit(close_stdout);
+
+	while((i = getopt_long(argc, argv, "+abfiphmoRrvV", longopts, NULL)) != -1)
+	{
+		int ret = EXIT_FAILURE;
+
+		switch (i) {
+		case 'a':
+			all_tasks = 1;
+			break;
+		case 'b':
+#ifdef SCHED_BATCH
+			policy = SCHED_BATCH;
+#endif
+			break;
+		case 'f':
+			policy = SCHED_FIFO;
+			break;
+		case 'R':
+#ifdef SCHED_RESET_ON_FORK
+			policy_flag |= SCHED_RESET_ON_FORK;
+#endif
+			break;
+		case 'i':
+#ifdef SCHED_IDLE
+			policy = SCHED_IDLE;
+#endif
+			break;
+		case 'm':
+			show_min_max();
+			return EXIT_SUCCESS;
+		case 'o':
+			policy = SCHED_OTHER;
+			break;
+		case 'p':
+			errno = 0;
+			pid = strtos32_or_err(argv[argc - 1], _("invalid PID argument"));
+			break;
+		case 'r':
+			policy = SCHED_RR;
+			break;
+		case 'v':
+			verbose = 1;
+			break;
+		case 'V':
+			printf("%s from %s\n", program_invocation_short_name,
+					       PACKAGE_STRING);
+			return EXIT_SUCCESS;
+		case 'h':
+			ret = EXIT_SUCCESS;
+			/* fallthrough */
+		default:
+			show_usage(ret);
+		}
+	}
+
+	if (((pid > -1) && argc - optind < 1) ||
+	    ((pid == -1) && argc - optind < 2))
+		show_usage(EXIT_FAILURE);
+
+	if ((pid > -1) && (verbose || argc - optind == 1)) {
+		if (all_tasks) {
+			pid_t tid;
+			struct proc_tasks *ts = proc_open_tasks(pid);
+
+			if (!ts)
+				err(EXIT_FAILURE, _("cannot obtain the list of tasks"));
+			while (!proc_next_tid(ts, &tid))
+				show_rt_info(tid, FALSE);
+			proc_close_tasks(ts);
+		} else
+			show_rt_info(pid, FALSE);
+
+		if (argc - optind == 1)
+			return EXIT_SUCCESS;
+	}
+
+	errno = 0;
+	priority = strtos32_or_err(argv[optind], _("invalid priority argument"));
+
+#ifdef SCHED_RESET_ON_FORK
+	/* sanity check */
+	if ((policy_flag & SCHED_RESET_ON_FORK) &&
+	    !(policy == SCHED_FIFO || policy == SCHED_RR))
+		errx(EXIT_FAILURE, _("SCHED_RESET_ON_FORK flag is suppoted for "
+				     "SCHED_FIFO and SCHED_RR policies only"));
+#endif
+
+	policy |= policy_flag;
+
+	if (pid == -1)
+		pid = 0;
+	sp.sched_priority = priority;
+
+	if (all_tasks) {
+		pid_t tid;
+		struct proc_tasks *ts = proc_open_tasks(pid);
+
+		if (!ts)
+			err(EXIT_FAILURE, _("cannot obtain the list of tasks"));
+		while (!proc_next_tid(ts, &tid))
+			if (sched_setscheduler(tid, policy, &sp) == -1)
+				err(EXIT_FAILURE, _("failed to set tid %d's policy"), tid);
+		proc_close_tasks(ts);
+	} else if (sched_setscheduler(pid, policy, &sp) == -1)
+		err(EXIT_FAILURE, _("failed to set pid %d's policy"), pid);
+
+	if (verbose)
+		show_rt_info(pid, TRUE);
+
+	if (!pid) {
+		argv += optind + 1;
+		execvp(argv[0], argv);
+		perror("execvp");
+		err(EXIT_FAILURE, _("failed to execute %s"), argv[0]);
+	}
+
+	return EXIT_SUCCESS;
+}