diff options
| author | Nysal Jan K.A | 2023-08-14 13:39:27 +0530 |
|---|---|---|
| committer | Greg Kroah-Hartman | 2023-09-13 09:42:29 +0200 |
| commit | 7d31730c5d81d229e3c4b6a1d7ca2f441a24880c (patch) | |
| tree | a2d097ab92ce21a5cdbc22f7bdb4b8fb47cd99c0 /tools | |
| parent | 048d1a8b9da8d4d36ae4b092342740f08bb7346a (diff) | |
selftests/futex: Order calls to futex_lock_pi
[ Upstream commit fbf4dec702774286db409815ffb077711a96b824 ]
Observed occassional failures in the futex_wait_timeout test:
ok 1 futex_wait relative succeeds
ok 2 futex_wait_bitset realtime succeeds
ok 3 futex_wait_bitset monotonic succeeds
ok 4 futex_wait_requeue_pi realtime succeeds
ok 5 futex_wait_requeue_pi monotonic succeeds
not ok 6 futex_lock_pi realtime returned 0
......
The test expects the child thread to complete some steps before
the parent thread gets to run. There is an implicit expectation
of the order of invocation of futex_lock_pi between the child thread
and the parent thread. Make this order explicit. If the order is
not met, the futex_lock_pi call in the parent thread succeeds and
will not timeout.
Fixes: f4addd54b161 ("selftests: futex: Expand timeout test")
Signed-off-by: Nysal Jan K.A <nysal@linux.ibm.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'tools')
| -rw-r--r-- | tools/testing/selftests/futex/functional/futex_wait_timeout.c | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/tools/testing/selftests/futex/functional/futex_wait_timeout.c b/tools/testing/selftests/futex/functional/futex_wait_timeout.c index 3651ce17beeb..d183f878360b 100644 --- a/tools/testing/selftests/futex/functional/futex_wait_timeout.c +++ b/tools/testing/selftests/futex/functional/futex_wait_timeout.c @@ -24,6 +24,7 @@ static long timeout_ns = 100000; /* 100us default timeout */ static futex_t futex_pi; +static pthread_barrier_t barrier; void usage(char *prog) { @@ -48,6 +49,8 @@ void *get_pi_lock(void *arg) if (ret != 0) error("futex_lock_pi failed\n", ret); + pthread_barrier_wait(&barrier); + /* Blocks forever */ ret = futex_wait(&lock, 0, NULL, 0); error("futex_wait failed\n", ret); @@ -130,6 +133,7 @@ int main(int argc, char *argv[]) basename(argv[0])); ksft_print_msg("\tArguments: timeout=%ldns\n", timeout_ns); + pthread_barrier_init(&barrier, NULL, 2); pthread_create(&thread, NULL, get_pi_lock, NULL); /* initialize relative timeout */ @@ -163,6 +167,9 @@ int main(int argc, char *argv[]) res = futex_wait_requeue_pi(&f1, f1, &futex_pi, &to, 0); test_timeout(res, &ret, "futex_wait_requeue_pi monotonic", ETIMEDOUT); + /* Wait until the other thread calls futex_lock_pi() */ + pthread_barrier_wait(&barrier); + pthread_barrier_destroy(&barrier); /* * FUTEX_LOCK_PI with CLOCK_REALTIME * Due to historical reasons, FUTEX_LOCK_PI supports only realtime |