Several CI runs failed in the libarena parallel tests with -4 (-EINTR) [1],
which says nothing about what actually went wrong.
Two workers can fail like this:
worker 1: gives up, e.g. the rendezvous times out, sets test_abort and
returns its own error (-ETIMEDOUT)
worker 2: sees test_abort and returns -EINTR
-EINTR only means "someone else already gave up", so it carries no
information. Which of the two gets reported depends on the order
pthread_join() collects them, because
err = err ?: (long)thread_ret;
keeps the first non-zero value and drops the rest. When the -EINTR worker
comes first, the error describing the actual failure is lost.
Let any other error win over -EINTR, and log each worker that returned an
error.
It is still unclear whether the timeouts come from CI load or from a
problem in the test itself. Report the error accurately first, so the next
failure can be diagnosed.
[1]:
https://github.com/kernel-patches/bpf/actions/runs/29867905253/job/88764463566
https://github.com/kernel-patches/bpf/actions/runs/29878191901/job/88794845824
Signed-off-by: Jiayuan Chen <[email protected]>
---
.../testing/selftests/bpf/prog_tests/libarena.c | 17 ++++++++++++++++-
1 file changed, 16 insertions(+), 1 deletion(-)
diff --git a/tools/testing/selftests/bpf/prog_tests/libarena.c
b/tools/testing/selftests/bpf/prog_tests/libarena.c
index df7e4b8dc394..65743920ff69 100644
--- a/tools/testing/selftests/bpf/prog_tests/libarena.c
+++ b/tools/testing/selftests/bpf/prog_tests/libarena.c
@@ -112,13 +112,28 @@ static int run_libarena_parallel_test_workers(struct
libarena *skel,
for (i = 0; i < nthreads; i++) {
+ int worker_err;
+
ret = pthread_join(threads[i], &thread_ret);
if (!ASSERT_OK(ret, "pthread_join")) {
err = err ?: ret;
continue;
}
- err = err ?: (long)thread_ret;
+ worker_err = (long)thread_ret;
+ if (!worker_err)
+ continue;
+
+ /*
+ * A worker that bails out because another one already gave up
+ * reports -EINTR. That is collateral damage, so let any other
+ * error win: it tells us what actually went wrong.
+ */
+ if (!err || err == -EINTR)
+ err = worker_err;
+
+ fprintf(stdout, "%.*s__%d returned %d\n", (int)prefixlen, name,
+ i, worker_err);
}
free(threads);
--
2.43.0
