[igt-dev] [PATCH i-g-t 1/7] gem_wsim: Check sleep times

[Tvrtko Ursulin]

From: Tvrtko Ursulin <tvrtko.ursulin at intel.com>

Notice in more places if we are running behind.

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
---
 benchmarks/gem_wsim.c | 52 ++++++++++++++++++++++++++++++++++++++-----
 1 file changed, 46 insertions(+), 6 deletions(-)

diff --git a/benchmarks/gem_wsim.c b/benchmarks/gem_wsim.c
index 80f180829241..ead91b0f009b 100644
--- a/benchmarks/gem_wsim.c
+++ b/benchmarks/gem_wsim.c
@@ -1718,6 +1718,21 @@ static bool sync_deps(struct workload *wrk, struct w_step *w)
 	return synced;
 }
 
+static unsigned int measured_usleep(unsigned int usec)
+{
+	struct timespec ts = { };
+	unsigned int slept;
+
+	slept = igt_nsec_elapsed(&ts);
+	igt_assert(slept == 0);
+	do {
+		usleep(usec - slept);
+		slept = igt_nsec_elapsed(&ts) / 1000;
+	} while (slept < usec);
+
+	return igt_nsec_elapsed(&ts);
+}
+
 static void *run_workload(void *data)
 {
 	struct workload *wrk = (struct workload *)data;
@@ -1739,7 +1754,7 @@ static void *run_workload(void *data)
 	     count++) {
 		unsigned int cur_seqno = wrk->sync_seqno;
 
-		clock_gettime(CLOCK_MONOTONIC, &wrk->repeat_start);
+		igt_gettime(&wrk->repeat_start);
 
 		for (i = 0, w = wrk->steps; wrk->run && (i < wrk->nr_steps);
 		     i++, w++) {
@@ -1751,13 +1766,14 @@ static void *run_workload(void *data)
 			} else if (w->type == PERIOD) {
 				struct timespec now;
 
-				clock_gettime(CLOCK_MONOTONIC, &now);
+				igt_gettime(&now);
 				do_sleep = w->period -
 					   elapsed_us(&wrk->repeat_start, &now);
 				if (do_sleep < 0) {
-					if (verbose > 1)
-						printf("%u: Dropped period @ %u/%u (%dus late)!\n",
-						       wrk->id, count, i, do_sleep);
+					if (verbose > 1 &&
+					    -do_sleep > 10 * w->period / 100)
+						printf("%u: Missed period @ %u/%u (%dus late)!\n",
+						       wrk->id, count, i, -do_sleep);
 					continue;
 				}
 			} else if (w->type == SYNC) {
@@ -1793,7 +1809,31 @@ static void *run_workload(void *data)
 			}
 
 			if (do_sleep || w->type == PERIOD) {
-				usleep(do_sleep);
+				long slept = measured_usleep(do_sleep) / 1000;
+
+				if ( w->type == PERIOD) {
+					struct timespec now;
+
+					igt_gettime(&now);
+
+					slept = elapsed_us(&wrk->repeat_start,
+							   &now);
+
+					if (verbose > 1 &&
+					    slept > (110 * w->period / 100))
+						printf("%u: Overslept period by %ldus @ %u/%u! (%uus)\n",
+						       wrk->id,
+						       -slept, count,
+						       i, w->period);
+				} else {
+					if (verbose > 1 &&
+					    slept > (110 * do_sleep / 100))
+						printf("%u: Overslept by %ldus @ %u/%u! (%uus)\n",
+						       wrk->id,
+						       slept - do_sleep, count,
+						       i, do_sleep);
+				}
+
 				continue;
 			}
 
-- 
2.17.1