[linux-2.6-block.git] / tools / perf / bench / sched-pipe.c

// SPDX-License-Identifier: GPL-2.0
/*
 *
 * sched-pipe.c
 *
 * pipe: Benchmark for pipe()
 *
 * Based on pipe-test-1m.c by Ingo Molnar <mingo@redhat.com>
 *  http://people.redhat.com/mingo/cfs-scheduler/tools/pipe-test-1m.c
 * Ported to perf by Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp>
 */
#include <subcmd/parse-options.h>
#include <api/fs/fs.h>
#include "bench.h"
#include "util/cgroup.h"

#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <signal.h>
#include <sys/wait.h>
#include <string.h>
#include <errno.h>
#include <fcntl.h>
#include <assert.h>
#include <sys/epoll.h>
#include <sys/time.h>
#include <sys/types.h>
#include <sys/syscall.h>
#include <linux/time64.h>

#include <pthread.h>

struct thread_data {
	int			nr;
	int			pipe_read;
	int			pipe_write;
	struct epoll_event      epoll_ev;
	int			epoll_fd;
	bool			cgroup_failed;
	pthread_t		pthread;
};

#define LOOPS_DEFAULT 1000000
static	int			loops = LOOPS_DEFAULT;

/* Use processes by default: */
static bool			threaded;

static bool			nonblocking;
static char			*cgrp_names[2];
static struct cgroup		*cgrps[2];

static int parse_two_cgroups(const struct option *opt __maybe_unused,
			     const char *str, int unset __maybe_unused)
{
	char *p = strdup(str);
	char *q;
	int ret = -1;

	if (p == NULL) {
		fprintf(stderr, "memory allocation failure\n");
		return -1;
	}

	q = strchr(p, ',');
	if (q == NULL) {
		fprintf(stderr, "it should have two cgroup names: %s\n", p);
		goto out;
	}
	*q = '\0';

	cgrp_names[0] = strdup(p);
	cgrp_names[1] = strdup(q + 1);

	if (cgrp_names[0] == NULL || cgrp_names[1] == NULL) {
		fprintf(stderr, "memory allocation failure\n");
		goto out;
	}
	ret = 0;

out:
	free(p);
	return ret;
}

static const struct option options[] = {
	OPT_BOOLEAN('n', "nonblocking",	&nonblocking,	"Use non-blocking operations"),
	OPT_INTEGER('l', "loop",	&loops,		"Specify number of loops"),
	OPT_BOOLEAN('T', "threaded",	&threaded,	"Specify threads/process based task setup"),
	OPT_CALLBACK('G', "cgroups", NULL, "SEND,RECV",
		     "Put sender and receivers in given cgroups",
		     parse_two_cgroups),
	OPT_END()
};

static const char * const bench_sched_pipe_usage[] = {
	"perf bench sched pipe <options>",
	NULL
};

static int enter_cgroup(int nr)
{
	char buf[32];
	int fd, len, ret;
	int saved_errno;
	struct cgroup *cgrp;
	pid_t pid;

	if (cgrp_names[nr] == NULL)
		return 0;

	if (cgrps[nr] == NULL) {
		cgrps[nr] = cgroup__new(cgrp_names[nr], /*do_open=*/true);
		if (cgrps[nr] == NULL)
			goto err;
	}
	cgrp = cgrps[nr];

	if (threaded)
		pid = syscall(__NR_gettid);
	else
		pid = getpid();

	snprintf(buf, sizeof(buf), "%d\n", pid);
	len = strlen(buf);

	/* try cgroup v2 interface first */
	if (threaded)
		fd = openat(cgrp->fd, "cgroup.threads", O_WRONLY);
	else
		fd = openat(cgrp->fd, "cgroup.procs", O_WRONLY);

	/* try cgroup v1 if failed */
	if (fd < 0 && errno == ENOENT)
		fd = openat(cgrp->fd, "tasks", O_WRONLY);

	if (fd < 0)
		goto err;

	ret = write(fd, buf, len);
	close(fd);

	if (ret != len) {
		printf("Cannot enter to cgroup: %s\n", cgrp->name);
		return -1;
	}
	return 0;

err:
	saved_errno = errno;
	printf("Failed to open cgroup file in %s\n", cgrp_names[nr]);

	if (saved_errno == ENOENT) {
		char mnt[PATH_MAX];

		if (cgroupfs_find_mountpoint(mnt, sizeof(mnt), "perf_event") == 0)
			printf(" Hint: create the cgroup first, like 'mkdir %s/%s'\n",
			       mnt, cgrp_names[nr]);
	} else if (saved_errno == EACCES && geteuid() > 0) {
		printf(" Hint: try to run as root\n");
	}

	return -1;
}

static void exit_cgroup(int nr)
{
	cgroup__put(cgrps[nr]);
	free(cgrp_names[nr]);
}

static inline int read_pipe(struct thread_data *td)
{
	int ret, m;
retry:
	if (nonblocking) {
		ret = epoll_wait(td->epoll_fd, &td->epoll_ev, 1, -1);
		if (ret < 0)
			return ret;
	}
	ret = read(td->pipe_read, &m, sizeof(int));
	if (nonblocking && ret < 0 && errno == EWOULDBLOCK)
		goto retry;
	return ret;
}

static void *worker_thread(void *__tdata)
{
	struct thread_data *td = __tdata;
	int i, ret, m = 0;

	ret = enter_cgroup(td->nr);
	if (ret < 0) {
		td->cgroup_failed = true;
		return NULL;
	}

	if (nonblocking) {
		td->epoll_ev.events = EPOLLIN;
		td->epoll_fd = epoll_create(1);
		BUG_ON(td->epoll_fd < 0);
		BUG_ON(epoll_ctl(td->epoll_fd, EPOLL_CTL_ADD, td->pipe_read, &td->epoll_ev) < 0);
	}

	for (i = 0; i < loops; i++) {
		ret = write(td->pipe_write, &m, sizeof(int));
		BUG_ON(ret != sizeof(int));
		ret = read_pipe(td);
		BUG_ON(ret != sizeof(int));
	}

	return NULL;
}

int bench_sched_pipe(int argc, const char **argv)
{
	struct thread_data threads[2] = {};
	struct thread_data *td;
	int pipe_1[2], pipe_2[2];
	struct timeval start, stop, diff;
	unsigned long long result_usec = 0;
	int nr_threads = 2;
	int t;

	/*
	 * why does "ret" exist?
	 * discarding returned value of read(), write()
	 * causes error in building environment for perf
	 */
	int __maybe_unused ret, wait_stat, flags = 0;
	pid_t pid, retpid __maybe_unused;

	argc = parse_options(argc, argv, options, bench_sched_pipe_usage, 0);

	if (nonblocking)
		flags |= O_NONBLOCK;

	BUG_ON(pipe2(pipe_1, flags));
	BUG_ON(pipe2(pipe_2, flags));

	gettimeofday(&start, NULL);

	for (t = 0; t < nr_threads; t++) {
		td = threads + t;

		td->nr = t;

		if (t == 0) {
			td->pipe_read = pipe_1[0];
			td->pipe_write = pipe_2[1];
		} else {
			td->pipe_write = pipe_1[1];
			td->pipe_read = pipe_2[0];
		}
	}

	if (threaded) {
		for (t = 0; t < nr_threads; t++) {
			td = threads + t;

			ret = pthread_create(&td->pthread, NULL, worker_thread, td);
			BUG_ON(ret);
		}

		for (t = 0; t < nr_threads; t++) {
			td = threads + t;

			ret = pthread_join(td->pthread, NULL);
			BUG_ON(ret);
		}
	} else {
		pid = fork();
		assert(pid >= 0);

		if (!pid) {
			worker_thread(threads + 0);
			exit(0);
		} else {
			worker_thread(threads + 1);
		}

		retpid = waitpid(pid, &wait_stat, 0);
		assert((retpid == pid) && WIFEXITED(wait_stat));
	}

	gettimeofday(&stop, NULL);
	timersub(&stop, &start, &diff);

	exit_cgroup(0);
	exit_cgroup(1);

	if (threads[0].cgroup_failed || threads[1].cgroup_failed)
		return 0;

	switch (bench_format) {
	case BENCH_FORMAT_DEFAULT:
		printf("# Executed %d pipe operations between two %s\n\n",
			loops, threaded ? "threads" : "processes");

		result_usec = diff.tv_sec * USEC_PER_SEC;
		result_usec += diff.tv_usec;

		printf(" %14s: %lu.%03lu [sec]\n\n", "Total time",
		       (unsigned long) diff.tv_sec,
		       (unsigned long) (diff.tv_usec / USEC_PER_MSEC));

		printf(" %14lf usecs/op\n",
		       (double)result_usec / (double)loops);
		printf(" %14d ops/sec\n",
		       (int)((double)loops /
			     ((double)result_usec / (double)USEC_PER_SEC)));
		break;

	case BENCH_FORMAT_SIMPLE:
		printf("%lu.%03lu\n",
		       (unsigned long) diff.tv_sec,
		       (unsigned long) (diff.tv_usec / USEC_PER_MSEC));
		break;

	default:
		/* reaching here is something disaster */
		fprintf(stderr, "Unknown format:%d\n", bench_format);
		exit(1);
		break;
	}

	return 0;
}
Commit	Line	Data
	1	// SPDX-License-Identifier: GPL-2.0
	2	/*
	3	*
	4	* sched-pipe.c
	5	*
	6	* pipe: Benchmark for pipe()
	7	*
	8	* Based on pipe-test-1m.c by Ingo Molnar <mingo@redhat.com>
	9	* http://people.redhat.com/mingo/cfs-scheduler/tools/pipe-test-1m.c
	10	* Ported to perf by Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp>
	11	*/
	12	#include <subcmd/parse-options.h>
	13	#include <api/fs/fs.h>
	14	#include "bench.h"
	15	#include "util/cgroup.h"
	16
	17	#include <unistd.h>
	18	#include <stdio.h>
	19	#include <stdlib.h>
	20	#include <signal.h>
	21	#include <sys/wait.h>
	22	#include <string.h>
	23	#include <errno.h>
	24	#include <fcntl.h>
	25	#include <assert.h>
	26	#include <sys/epoll.h>
	27	#include <sys/time.h>
	28	#include <sys/types.h>
	29	#include <sys/syscall.h>
	30	#include <linux/time64.h>
	31
	32	#include <pthread.h>
	33
	34	struct thread_data {
	35	int nr;
	36	int pipe_read;
	37	int pipe_write;
	38	struct epoll_event epoll_ev;
	39	int epoll_fd;
	40	bool cgroup_failed;
	41	pthread_t pthread;
	42	};
	43
	44	#define LOOPS_DEFAULT 1000000
	45	static int loops = LOOPS_DEFAULT;
	46
	47	/* Use processes by default: */
	48	static bool threaded;
	49
	50	static bool nonblocking;
	51	static char *cgrp_names[2];
	52	static struct cgroup *cgrps[2];
	53
	54	static int parse_two_cgroups(const struct option *opt __maybe_unused,
	55	const char *str, int unset __maybe_unused)
	56	{
	57	char *p = strdup(str);
	58	char *q;
	59	int ret = -1;
	60
	61	if (p == NULL) {
	62	fprintf(stderr, "memory allocation failure\n");
	63	return -1;
	64	}
	65
	66	q = strchr(p, ',');
	67	if (q == NULL) {
	68	fprintf(stderr, "it should have two cgroup names: %s\n", p);
	69	goto out;
	70	}
	71	*q = '\0';
	72
	73	cgrp_names[0] = strdup(p);
	74	cgrp_names[1] = strdup(q + 1);
	75
	76	if (cgrp_names[0] == NULL \|\| cgrp_names[1] == NULL) {
	77	fprintf(stderr, "memory allocation failure\n");
	78	goto out;
	79	}
	80	ret = 0;
	81
	82	out:
	83	free(p);
	84	return ret;
	85	}
	86
	87	static const struct option options[] = {
	88	OPT_BOOLEAN('n', "nonblocking", &nonblocking, "Use non-blocking operations"),
	89	OPT_INTEGER('l', "loop", &loops, "Specify number of loops"),
	90	OPT_BOOLEAN('T', "threaded", &threaded, "Specify threads/process based task setup"),
	91	OPT_CALLBACK('G', "cgroups", NULL, "SEND,RECV",
	92	"Put sender and receivers in given cgroups",
	93	parse_two_cgroups),
	94	OPT_END()
	95	};
	96
	97	static const char * const bench_sched_pipe_usage[] = {
	98	"perf bench sched pipe <options>",
	99	NULL
	100	};
	101
	102	static int enter_cgroup(int nr)
	103	{
	104	char buf[32];
	105	int fd, len, ret;
	106	int saved_errno;
	107	struct cgroup *cgrp;
	108	pid_t pid;
	109
	110	if (cgrp_names[nr] == NULL)
	111	return 0;
	112
	113	if (cgrps[nr] == NULL) {
	114	cgrps[nr] = cgroup__new(cgrp_names[nr], /do_open=/true);
	115	if (cgrps[nr] == NULL)
	116	goto err;
	117	}
	118	cgrp = cgrps[nr];
	119
	120	if (threaded)
	121	pid = syscall(__NR_gettid);
	122	else
	123	pid = getpid();
	124
	125	snprintf(buf, sizeof(buf), "%d\n", pid);
	126	len = strlen(buf);
	127
	128	/* try cgroup v2 interface first */
	129	if (threaded)
	130	fd = openat(cgrp->fd, "cgroup.threads", O_WRONLY);
	131	else
	132	fd = openat(cgrp->fd, "cgroup.procs", O_WRONLY);
	133
	134	/* try cgroup v1 if failed */
	135	if (fd < 0 && errno == ENOENT)
	136	fd = openat(cgrp->fd, "tasks", O_WRONLY);
	137
	138	if (fd < 0)
	139	goto err;
	140
	141	ret = write(fd, buf, len);
	142	close(fd);
	143
	144	if (ret != len) {
	145	printf("Cannot enter to cgroup: %s\n", cgrp->name);
	146	return -1;
	147	}
	148	return 0;
	149
	150	err:
	151	saved_errno = errno;
	152	printf("Failed to open cgroup file in %s\n", cgrp_names[nr]);
	153
	154	if (saved_errno == ENOENT) {
	155	char mnt[PATH_MAX];
	156
	157	if (cgroupfs_find_mountpoint(mnt, sizeof(mnt), "perf_event") == 0)
	158	printf(" Hint: create the cgroup first, like 'mkdir %s/%s'\n",
	159	mnt, cgrp_names[nr]);
	160	} else if (saved_errno == EACCES && geteuid() > 0) {
	161	printf(" Hint: try to run as root\n");
	162	}
	163
	164	return -1;
	165	}
	166
	167	static void exit_cgroup(int nr)
	168	{
	169	cgroup__put(cgrps[nr]);
	170	free(cgrp_names[nr]);
	171	}
	172
	173	static inline int read_pipe(struct thread_data *td)
	174	{
	175	int ret, m;
	176	retry:
	177	if (nonblocking) {
	178	ret = epoll_wait(td->epoll_fd, &td->epoll_ev, 1, -1);
	179	if (ret < 0)
	180	return ret;
	181	}
	182	ret = read(td->pipe_read, &m, sizeof(int));
	183	if (nonblocking && ret < 0 && errno == EWOULDBLOCK)
	184	goto retry;
	185	return ret;
	186	}
	187
	188	static void worker_thread(void __tdata)
	189	{
	190	struct thread_data *td = __tdata;
	191	int i, ret, m = 0;
	192
	193	ret = enter_cgroup(td->nr);
	194	if (ret < 0) {
	195	td->cgroup_failed = true;
	196	return NULL;
	197	}
	198
	199	if (nonblocking) {
	200	td->epoll_ev.events = EPOLLIN;
	201	td->epoll_fd = epoll_create(1);
	202	BUG_ON(td->epoll_fd < 0);
	203	BUG_ON(epoll_ctl(td->epoll_fd, EPOLL_CTL_ADD, td->pipe_read, &td->epoll_ev) < 0);
	204	}
	205
	206	for (i = 0; i < loops; i++) {
	207	ret = write(td->pipe_write, &m, sizeof(int));
	208	BUG_ON(ret != sizeof(int));
	209	ret = read_pipe(td);
	210	BUG_ON(ret != sizeof(int));
	211	}
	212
	213	return NULL;
	214	}
	215
	216	int bench_sched_pipe(int argc, const char **argv)
	217	{
	218	struct thread_data threads[2] = {};
	219	struct thread_data *td;
	220	int pipe_1[2], pipe_2[2];
	221	struct timeval start, stop, diff;
	222	unsigned long long result_usec = 0;
	223	int nr_threads = 2;
	224	int t;
	225
	226	/*
	227	* why does "ret" exist?
	228	* discarding returned value of read(), write()
	229	* causes error in building environment for perf
	230	*/
	231	int __maybe_unused ret, wait_stat, flags = 0;
	232	pid_t pid, retpid __maybe_unused;
	233
	234	argc = parse_options(argc, argv, options, bench_sched_pipe_usage, 0);
	235
	236	if (nonblocking)
	237	flags \|= O_NONBLOCK;
	238
	239	BUG_ON(pipe2(pipe_1, flags));
	240	BUG_ON(pipe2(pipe_2, flags));
	241
	242	gettimeofday(&start, NULL);
	243
	244	for (t = 0; t < nr_threads; t++) {
	245	td = threads + t;
	246
	247	td->nr = t;
	248
	249	if (t == 0) {
	250	td->pipe_read = pipe_1[0];
	251	td->pipe_write = pipe_2[1];
	252	} else {
	253	td->pipe_write = pipe_1[1];
	254	td->pipe_read = pipe_2[0];
	255	}
	256	}
	257
	258	if (threaded) {
	259	for (t = 0; t < nr_threads; t++) {
	260	td = threads + t;
	261
	262	ret = pthread_create(&td->pthread, NULL, worker_thread, td);
	263	BUG_ON(ret);
	264	}
	265
	266	for (t = 0; t < nr_threads; t++) {
	267	td = threads + t;
	268
	269	ret = pthread_join(td->pthread, NULL);
	270	BUG_ON(ret);
	271	}
	272	} else {
	273	pid = fork();
	274	assert(pid >= 0);
	275
	276	if (!pid) {
	277	worker_thread(threads + 0);
	278	exit(0);
	279	} else {
	280	worker_thread(threads + 1);
	281	}
	282
	283	retpid = waitpid(pid, &wait_stat, 0);
	284	assert((retpid == pid) && WIFEXITED(wait_stat));
	285	}
	286
	287	gettimeofday(&stop, NULL);
	288	timersub(&stop, &start, &diff);
	289
	290	exit_cgroup(0);
	291	exit_cgroup(1);
	292
	293	if (threads[0].cgroup_failed \|\| threads[1].cgroup_failed)
	294	return 0;
	295
	296	switch (bench_format) {
	297	case BENCH_FORMAT_DEFAULT:
	298	printf("# Executed %d pipe operations between two %s\n\n",
	299	loops, threaded ? "threads" : "processes");
	300
	301	result_usec = diff.tv_sec * USEC_PER_SEC;
	302	result_usec += diff.tv_usec;
	303
	304	printf(" %14s: %lu.%03lu [sec]\n\n", "Total time",
	305	(unsigned long) diff.tv_sec,
	306	(unsigned long) (diff.tv_usec / USEC_PER_MSEC));
	307
	308	printf(" %14lf usecs/op\n",
	309	(double)result_usec / (double)loops);
	310	printf(" %14d ops/sec\n",
	311	(int)((double)loops /
	312	((double)result_usec / (double)USEC_PER_SEC)));
	313	break;
	314
	315	case BENCH_FORMAT_SIMPLE:
	316	printf("%lu.%03lu\n",
	317	(unsigned long) diff.tv_sec,
	318	(unsigned long) (diff.tv_usec / USEC_PER_MSEC));
	319	break;
	320
	321	default:
	322	/* reaching here is something disaster */
	323	fprintf(stderr, "Unknown format:%d\n", bench_format);
	324	exit(1);
	325	break;
	326	}
	327
	328	return 0;
	329	}