Skip to content

Commit

Permalink
selftests/bpf: Bump internal send_signal/send_signal_tracepoint timeout
Browse files Browse the repository at this point in the history
The send_signal/send_signal_tracepoint is pretty flaky, with at least
one failure in every ten runs on a few attempts I've tried it:
  > test_send_signal_common:PASS:pipe_c2p 0 nsec
  > test_send_signal_common:PASS:pipe_p2c 0 nsec
  > test_send_signal_common:PASS:fork 0 nsec
  > test_send_signal_common:PASS:skel_open_and_load 0 nsec
  > test_send_signal_common:PASS:skel_attach 0 nsec
  > test_send_signal_common:PASS:pipe_read 0 nsec
  > test_send_signal_common:PASS:pipe_write 0 nsec
  > test_send_signal_common:PASS:reading pipe 0 nsec
  > test_send_signal_common:PASS:reading pipe error: size 0 0 nsec
  > test_send_signal_common:FAIL:incorrect result unexpected incorrect result: actual 48 != expected 50
  > test_send_signal_common:PASS:pipe_write 0 nsec
  > torvalds#139/1   send_signal/send_signal_tracepoint:FAIL

The reason does not appear to be a correctness issue in the strict
sense. Rather, we merely do not receive the signal we are waiting for
within the provided timeout.
Let's bump the timeout by a factor of ten. With that change I have not
been able to reproduce the failure in 150+ iterations. I am also sneaking
in a small simplification to the test_progs test selection logic.

Signed-off-by: Daniel Müller <[email protected]>
Signed-off-by: Andrii Nakryiko <[email protected]>
Acked-by: Jiri Olsa <[email protected]>
Acked-by: Yonghong Song <[email protected]>
Link: https://lore.kernel.org/bpf/[email protected]
  • Loading branch information
d-e-s-o authored and anakryiko committed Jul 29, 2022
1 parent a6df067 commit 639de43
Show file tree
Hide file tree
Showing 2 changed files with 3 additions and 6 deletions.
2 changes: 1 addition & 1 deletion tools/testing/selftests/bpf/prog_tests/send_signal.c
Original file line number Diff line number Diff line change
Expand Up @@ -64,7 +64,7 @@ static void test_send_signal_common(struct perf_event_attr *attr,
ASSERT_EQ(read(pipe_p2c[0], buf, 1), 1, "pipe_read");

/* wait a little for signal handler */
for (int i = 0; i < 100000000 && !sigusr1_received; i++)
for (int i = 0; i < 1000000000 && !sigusr1_received; i++)
j /= i + j + 1;

buf[0] = sigusr1_received ? '2' : '0';
Expand Down
7 changes: 2 additions & 5 deletions tools/testing/selftests/bpf/test_progs.c
Original file line number Diff line number Diff line change
Expand Up @@ -1604,11 +1604,8 @@ int main(int argc, char **argv)
struct prog_test_def *test = &prog_test_defs[i];

test->test_num = i + 1;
if (should_run(&env.test_selector,
test->test_num, test->test_name))
test->should_run = true;
else
test->should_run = false;
test->should_run = should_run(&env.test_selector,
test->test_num, test->test_name);

if ((test->run_test == NULL && test->run_serial_test == NULL) ||
(test->run_test != NULL && test->run_serial_test != NULL)) {
Expand Down

0 comments on commit 639de43

Please sign in to comment.