Commit 857f75ea authored by Yucong Sun's avatar Yucong Sun Committed by Andrii Nakryiko
Browse files

selftests/bpf: Add exponential backoff to map_delete_retriable in test_maps 



Using a fixed delay of 1 microsecond has proven flaky in slow CPU environment,
e.g. Github Actions CI system. This patch adds exponential backoff with a cap
of 50ms to reduce the flakiness of the test. Initial delay is chosen at random
in the range [0ms, 5ms).

Signed-off-by: default avatarYucong Sun <fallentree@fb.com>
Signed-off-by: default avatarAndrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210817045713.3307985-1-fallentree@fb.com
parent 3c3bd542

tools/testing/selftests/bpf/test_maps.c

+6 −1
Original line number Diff line number Diff line
@@ -1420,11 +1420,16 @@ static int map_update_retriable(int map_fd, const void *key, const void *value, 


static int map_delete_retriable(int map_fd, const void *key, int attempts)

{

	int delay = rand() % MIN_DELAY_RANGE_US;



	while (bpf_map_delete_elem(map_fd, key)) {

		if (!attempts || (errno != EAGAIN && errno != EBUSY))

			return -errno;



		usleep(1);

		if (delay <= MAX_DELAY_US / 2)

			delay *= 2;



		usleep(delay);

		attempts--;

	}