From 2b5cf9fb74848fe5742a56e872e6847b79933c0b Mon Sep 17 00:00:00 2001 From: Andrii Nakryiko Date: Wed, 11 Mar 2020 11:53:45 -0700 Subject: [PATCH] selftests/bpf: Guarantee that useep() calls nanosleep() syscall Some implementations of C runtime library won't call nanosleep() syscall from usleep(). But a bunch of kprobe/tracepoint selftests rely on nanosleep being called to trigger them. To make this more reliable, "override" usleep implementation and call nanosleep explicitly. Signed-off-by: Andrii Nakryiko Signed-off-by: Alexei Starovoitov Cc: Julia Kartseva Link: https://lore.kernel.org/bpf/20200311185345.3874602-1-andriin@fb.com Signed-off-by: Alexei Starovoitov --- tools/testing/selftests/bpf/test_progs.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/tools/testing/selftests/bpf/test_progs.c b/tools/testing/selftests/bpf/test_progs.c index a969c77e9456..2b0bc1171c9c 100644 --- a/tools/testing/selftests/bpf/test_progs.c +++ b/tools/testing/selftests/bpf/test_progs.c @@ -29,6 +29,15 @@ struct prog_test_def { int old_error_cnt; }; +/* Override C runtime library's usleep() implementation to ensure nanosleep() + * is always called. Usleep is frequently used in selftests as a way to + * trigger kprobe and tracepoints. + */ +int usleep(useconds_t usec) +{ + return syscall(__NR_nanosleep, usec * 1000UL); +} + static bool should_run(struct test_selector *sel, int num, const char *name) { int i;