selftests/bpf: Fix usdt_400 test case

usdt_400 test case relies on compiler using the same arg spec for
usdt_400 USDT. This assumption breaks with Clang (Clang generates
different arg specs with varying offsets relative to %rbp), so simplify
this further and hard-code the constant which will guarantee that arg
spec is the same across all 400 inlinings.

Fixes: 630301b0d5 ("selftests/bpf: Add basic USDT selftests")
Reported-by: Mykola Lysenko <mykolal@fb.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20220513173703.89271-1-andrii@kernel.org
This commit is contained in:
Andrii Nakryiko 2022-05-13 10:37:03 -07:00 committed by Daniel Borkmann
parent b2531d4bdc
commit 0d2d264893
1 changed files with 2 additions and 4 deletions

View File

@ -190,9 +190,7 @@ __weak void trigger_300_usdts(void)
static void __always_inline f400(int x __attribute__((unused)))
{
static int y;
STAP_PROBE1(test, usdt_400, y++);
STAP_PROBE1(test, usdt_400, 400);
}
/* this time we have 400 different USDT call sites, but they have uniform
@ -299,7 +297,7 @@ static void subtest_multispec_usdt(void)
trigger_400_usdts();
ASSERT_EQ(bss->usdt_100_called, 400, "usdt_400_called");
ASSERT_EQ(bss->usdt_100_sum, 399 * 400 / 2, "usdt_400_sum");
ASSERT_EQ(bss->usdt_100_sum, 400 * 400, "usdt_400_sum");
cleanup:
test_usdt__destroy(skel);