perf/bench/futex-requeue.c

1 // SPDX-License-Identifier: GPL-2.0
5  * futex-requeue: Block a bunch of threads on futex1 and requeue them
9  * requeues without waking up any tasks (in the non-pi case) -- thus
20 #include <subcmd/parse-options.h>
47 	 * Default to 1 in order to make the kernel work more.
59 	OPT_BOOLEAN( 'p', "pi", &params.pi, "Use PI-aware variants of FUTEX_CMP_REQUEUE"),
75 	printf("Requeued %d of %d threads in %.4f ms (+-%.2f%%)\n",  in print_summary()
87 	threads_starting--;  in workerfn()
225 		/* make sure all threads are already blocked */  in bench_futex_requeue()
234 		/* Ok, all threads are patiently blocked, start requeueing */  in bench_futex_requeue()
240 			 * For the regular non-pi case, do not wakeup any tasks  in bench_futex_requeue()
241 			 * blocked on futex1, allowing us to really measure  in bench_futex_requeue()
276 				nrequeued -= wakeups;  in bench_futex_requeue()
287 			/* everybody should be blocked on futex2, wake'em up */  in bench_futex_requeue()