/*
 * Copyright (C) 2013  Davidlohr Bueso <davidlohr@hp.com>
 *
 * futex-wake: Block a bunch of threads on a futex and wake'em up, N at a time.
 *
 * This program is particularly useful to measure the latency of nthread wakeups
 * in non-error situations:  all waiters are queued and all wake calls wakeup
 * one or more tasks, and thus the waitqueue is never empty.
 */

/* For the CLR_() macros */
#include <pthread.h>

#include <signal.h>
#include "../util/stat.h"
#include <subcmd/parse-options.h>
#include <linux/compiler.h>
#include <linux/kernel.h>
#include <linux/time64.h>
#include <errno.h>
#include "bench.h"
#include "futex.h"

#include <err.h>
#include <stdlib.h>
#include <sys/time.h>

/* all threads will block on the same futex */
static u_int32_t futex1 = 0;

/*
 * How many wakeups to do at a time.
 * Default to 1 in order to make the kernel work more.
 */
static unsigned int nwakes = 1;

pthread_t *worker;
static bool done = false, silent = false, fshared = false;
static pthread_mutex_t thread_lock;
static pthread_cond_t thread_parent, thread_worker;
static struct stats waketime_stats, wakeup_stats;
static unsigned int ncpus, threads_starting, nthreads = 0;
static int futex_flag = 0;

static const struct option options[] = {
	OPT_UINTEGER('t', "threads", &nthreads, "Specify amount of threads"),
	OPT_UINTEGER('w', "nwakes",  &nwakes,   "Specify amount of threads to wake at once"),
	OPT_BOOLEAN( 's', "silent",  &silent,   "Silent mode: do not display data/details"),
	OPT_BOOLEAN( 'S', "shared",  &fshared,  "Use shared futexes instead of private ones"),
	OPT_END()
};

static const char * const bench_futex_wake_usage[] = {
	"perf bench futex wake <options>",
	NULL
};

static void *workerfn(void *arg __maybe_unused)
{
	pthread_mutex_lock(&thread_lock);
	threads_starting--;
	if (!threads_starting)
		pthread_cond_signal(&thread_parent);
	pthread_cond_wait(&thread_worker, &thread_lock);
	pthread_mutex_unlock(&thread_lock);

	while (1) {
		if (futex_wait(&futex1, 0, NULL, futex_flag) != EINTR)
			break;
	}

	pthread_exit(NULL);
	return NULL;
}

static void print_summary(void)
{
	double waketime_avg = avg_stats(&waketime_stats);
	double waketime_stddev = stddev_stats(&waketime_stats);
	unsigned int wakeup_avg = avg_stats(&wakeup_stats);

	printf("Wokeup %d of %d threads in %.4f ms (+-%.2f%%)\n",
	       wakeup_avg,
	       nthreads,
	       waketime_avg / USEC_PER_MSEC,
	       rel_stddev_stats(waketime_stddev, waketime_avg));
}

static void block_threads(pthread_t *w,
			  pthread_attr_t thread_attr)
{
	cpu_set_t cpu;
	unsigned int i;

	threads_starting = nthreads;

	/* create and block all threads */
	for (i = 0; i < nthreads; i++) {
		CPU_ZERO(&cpu);
		CPU_SET(i % ncpus, &cpu);

		if (pthread_attr_setaffinity_np(&thread_attr, sizeof(cpu_set_t), &cpu))
			err(EXIT_FAILURE, "pthread_attr_setaffinity_np");

		if (pthread_create(&w[i], &thread_attr, workerfn, NULL))
			err(EXIT_FAILURE, "pthread_create");
	}
}

static void toggle_done(int sig __maybe_unused,
			siginfo_t *info __maybe_unused,
			void *uc __maybe_unused)
{
	done = true;
}

int bench_futex_wake(int argc, const char **argv,
		     const char *prefix __maybe_unused)
{
	int ret = 0;
	unsigned int i, j;
	struct sigaction act;
	pthread_attr_t thread_attr;

	argc = parse_options(argc, argv, options, bench_futex_wake_usage, 0);
	if (argc) {
		usage_with_options(bench_futex_wake_usage, options);
		exit(EXIT_FAILURE);
	}

	ncpus = sysconf(_SC_NPROCESSORS_ONLN);
	nwakes = futexbench_sanitize_numeric(nwakes);

	sigfillset(&act.sa_mask);
	act.sa_sigaction = toggle_done;
	sigaction(SIGINT, &act, NULL);

	if (!nthreads)
		nthreads = ncpus;
	else
		nthreads = futexbench_sanitize_numeric(nthreads);

	worker = calloc(nthreads, sizeof(*worker));
	if (!worker)
		err(EXIT_FAILURE, "calloc");

	if (!fshared)
		futex_flag = FUTEX_PRIVATE_FLAG;

	printf("Run summary [PID %d]: blocking on %d threads (at [%s] futex %p), "
	       "waking up %d at a time.\n\n",
	       getpid(), nthreads, fshared ? "shared":"private",  &futex1, nwakes);

	init_stats(&wakeup_stats);
	init_stats(&waketime_stats);
	pthread_attr_init(&thread_attr);
	pthread_mutex_init(&thread_lock, NULL);
	pthread_cond_init(&thread_parent, NULL);
	pthread_cond_init(&thread_worker, NULL);

	for (j = 0; j < bench_repeat && !done; j++) {
		unsigned int nwoken = 0;
		struct timeval start, end, runtime;

		/* create, launch & block all threads */
		block_threads(worker, thread_attr);

		/* make sure all threads are already blocked */
		pthread_mutex_lock(&thread_lock);
		while (threads_starting)
			pthread_cond_wait(&thread_parent, &thread_lock);
		pthread_cond_broadcast(&thread_worker);
		pthread_mutex_unlock(&thread_lock);

		usleep(100000);

		/* Ok, all threads are patiently blocked, start waking folks up */
		gettimeofday(&start, NULL);
		while (nwoken != nthreads)
			nwoken += futex_wake(&futex1, nwakes, futex_flag);
		gettimeofday(&end, NULL);
		timersub(&end, &start, &runtime);

		update_stats(&wakeup_stats, nwoken);
		update_stats(&waketime_stats, runtime.tv_usec);

		if (!silent) {
			printf("[Run %d]: Wokeup %d of %d threads in %.4f ms\n",
			       j + 1, nwoken, nthreads, runtime.tv_usec / (double)USEC_PER_MSEC);
		}

		for (i = 0; i < nthreads; i++) {
			ret = pthread_join(worker[i], NULL);
			if (ret)
				err(EXIT_FAILURE, "pthread_join");
		}

	}

	/* cleanup & report results */
	pthread_cond_destroy(&thread_parent);
	pthread_cond_destroy(&thread_worker);
	pthread_mutex_destroy(&thread_lock);
	pthread_attr_destroy(&thread_attr);

	print_summary();

	free(worker);
	return ret;
}
/cgit.cgi/linux/net-next.git/tree/?h=nds-private-remove&amp;id=3f67790d2b7e322bcf363ec717085dd78c3ea7cd'>7be20232078a2e801ed93bcdb72f0d955dd9836f</a> /<a href='/cgit.cgi/linux/net-next.git/tree/drivers/usb/dwc2?h=nds-private-remove&amp;id=3f67790d2b7e322bcf363ec717085dd78c3ea7cd'>drivers/usb/dwc2</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/drivers/usb/dwc2?h=nds-private-remove&amp;id=cd44691f7177b2c1e1509d1a17d9b198ebaa34eb'>cd44691f7177b2c1e1509d1a17d9b198ebaa34eb</a> (<a href='/cgit.cgi/linux/net-next.git/diff/drivers/usb/dwc2?h=nds-private-remove&amp;id=3f67790d2b7e322bcf363ec717085dd78c3ea7cd&amp;id2=cd44691f7177b2c1e1509d1a17d9b198ebaa34eb'>diff</a>)</td></tr><tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/drivers/usb/dwc2?h=nds-private-remove&amp;id=206c4720092d2a24bfefc041b377e889a220ffbf'>206c4720092d2a24bfefc041b377e889a220ffbf</a> (<a href='/cgit.cgi/linux/net-next.git/diff/drivers/usb/dwc2?h=nds-private-remove&amp;id=3f67790d2b7e322bcf363ec717085dd78c3ea7cd&amp;id2=206c4720092d2a24bfefc041b377e889a220ffbf'>diff</a>)</td></tr></table>
<div class='commit-subject'>Merge tag 'regulator-fix-v4.10-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator</div><div class='commit-msg'>Pull regulator fixes from Mark Brown:
 "Three changes here: two run of the mill driver specific fixes and a
  change from Mark Rutland which reverts some new device specific ACPI
  binding code which was added during the merge window as there are
  concerns about this sending the wrong signal about usage of regulators
  in ACPI systems"

* tag 'regulator-fix-v4.10-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator:
  regulator: fixed: Revert support for ACPI interface
  regulator: axp20x: AXP806: Fix dcdcb being set instead of dcdce
  regulator: twl6030: fix range comparison, allowing vsel = 59
</div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?h=nds-private-remove&amp;id=3f67790d2b7e322bcf363ec717085dd78c3ea7cd'>Diffstat</a> (limited to 'drivers/usb/dwc2')</div><table summary='diffstat' class='diffstat'>