[PATCH 29/31] selftests: ntsync: Add a stress test for contended waits.

Test a more realistic usage pattern, and one with heavy contention, in order to actually exercise ntsync's internal synchronization. This test has several threads in a tight loop acquiring a mutex, modifying some shared data, and then releasing the mutex. At the end we check if the data is consistent. Signed-off-by: Elizabeth Figura &lt;zfigura(a)codeweavers.com&gt; --- .../testing/selftests/drivers/ntsync/ntsync.c | 74 +++++++++++++++++++ 1 file changed, 74 insertions(+) diff --git a/tools/testing/selftests/drivers/ntsync/ntsync.c b/tools/testing/selftests/drivers/ntsync/ntsync.c index 40cfdd356ef4..aba513c9af01 100644 --- a/tools/testing/selftests/drivers/ntsync/ntsync.c +++ b/tools/testing/selftests/drivers/ntsync/ntsync.c @@ -1330,4 +1330,78 @@ TEST(alert_all) close(fd); } +#define STRESS_LOOPS 10000 +#define STRESS_THREADS 4 + +static unsigned int stress_counter; +static int stress_device, stress_start_event, stress_mutex; + +static void *stress_thread(void *arg) +{ + struct ntsync_wait_args wait_args = {0}; + __u32 index, count, i; + int ret; + + wait_args.timeout = UINT64_MAX; + wait_args.count = 1; + wait_args.objs = (uintptr_t)&stress_start_event; + wait_args.owner = gettid(); + wait_args.index = 0xdeadbeef; + + ioctl(stress_device, NTSYNC_IOC_WAIT_ANY, &wait_args); + + wait_args.objs = (uintptr_t)&stress_mutex; + + for (i = 0; i < STRESS_LOOPS; ++i) { + ioctl(stress_device, NTSYNC_IOC_WAIT_ANY, &wait_args); + + ++stress_counter; + + unlock_mutex(stress_mutex, wait_args.owner, &count); + } + + return NULL; +} + +TEST(stress_wait) +{ + struct ntsync_event_args event_args; + struct ntsync_mutex_args mutex_args; + pthread_t threads[STRESS_THREADS]; + __u32 signaled, i; + int ret; + + stress_device = open("/dev/ntsync", O_CLOEXEC | O_RDONLY); + ASSERT_LE(0, stress_device); + + mutex_args.owner = 0; + mutex_args.count = 0; + ret = ioctl(stress_device, NTSYNC_IOC_CREATE_MUTEX, &mutex_args); + EXPECT_EQ(0, ret); + stress_mutex = mutex_args.mutex; + + event_args.manual = 1; + event_args.signaled = 0; + ret = ioctl(stress_device, NTSYNC_IOC_CREATE_EVENT, &event_args); + EXPECT_EQ(0, ret); + stress_start_event = event_args.event; + + for (i = 0; i < STRESS_THREADS; ++i) + pthread_create(&threads[i], NULL, stress_thread, NULL); + + ret = ioctl(stress_start_event, NTSYNC_IOC_EVENT_SET, &signaled); + EXPECT_EQ(0, ret); + + for (i = 0; i < STRESS_THREADS; ++i) { + ret = pthread_join(threads[i], NULL); + EXPECT_EQ(0, ret); + } + + EXPECT_EQ(STRESS_LOOPS * STRESS_THREADS, stress_counter); + + close(stress_start_event); + close(stress_mutex); + close(stress_device); +} + TEST_HARNESS_MAIN -- 2.43.0