Commit 6f9661b2 authored by Davidlohr Bueso's avatar Davidlohr Bueso Committed by Arnaldo Carvalho de Melo
Browse files

perf bench futex, requeue: Robustify futex_wait() handling 



Do not assume success and account for EAGAIN or any other return value,
however unlikely.

Signed-off-by: default avatarDavidlohr Bueso <dbueso@suse.de>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lore.kernel.org/lkml/20210809043301.66002-7-dave@stgolabs.net


Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
parent d262e6a9

tools/perf/bench/futex-requeue.c

+14 −1
Original line number Diff line number Diff line
@@ -77,6 +77,8 @@ static void print_summary(void) 


static void *workerfn(void *arg __maybe_unused)

{

	int ret;



	pthread_mutex_lock(&thread_lock);

	threads_starting--;

	if (!threads_starting)
@@ -84,7 +86,18 @@ static void *workerfn(void *arg __maybe_unused) 
	pthread_cond_wait(&thread_worker, &thread_lock);

	pthread_mutex_unlock(&thread_lock);



	futex_wait(&futex1, 0, NULL, futex_flag);

	while (1) {

		ret = futex_wait(&futex1, 0, NULL, futex_flag);

		if (!ret)

			break;



		if (ret && errno != EAGAIN) {

			if (!params.silent)

				warn("futex_wait");

			break;

		}

	}



	return NULL;

}