Em Thu, Nov 03, 2022 at 12:27:01PM +0530, Athira Rajeev escreveu:

quoted

On 28-Oct-2022, at 9:12 PM, Kajol Jain [off-list ref] wrote:

Perf BPF filter test fails in environment where "kernel-debuginfo"
is not installed.

Test failure logs:
<<>>
42: BPF filter                            :
42.1: Basic BPF filtering                 : Ok
42.2: BPF pinning                         : Ok
42.3: BPF prologue generation             : FAILED!
<<>>

Enabling verbose option provided debug logs, which says debuginfo
needs to be installed. Snippet of verbose logs:

<<>>
42.3: BPF prologue generation                                       :

--- start ---

test child forked, pid 28218
<<>>
Rebuild with CONFIG_DEBUG_INFO=y, or install an appropriate debuginfo
package.
bpf_probe: failed to convert perf probe events
Failed to add events selected by BPF
test child finished with -1
---- end ----
BPF filter subtest 3: FAILED!
<<>>

Here subtest, "BPF prologue generation" failed and
logs shows debuginfo is needed. After installing
kernel-debuginfo package, testcase passes.

Subtest "BPF prologue generation" failed because, the "do_test"
function returns "TEST_FAIL" without checking the error type
returned by "parse_events_load_bpf_obj" function.
Function parse_events_load_bpf_obj can also return error of type
"-ENOENT" incase kernel-debuginfo package is not installed. Fix this
by adding check for -ENOENT error.

Test result after the patch changes:

Test failure logs:
<<>>
42: BPF filter                 :
42.1: Basic BPF filtering      : Ok
42.2: BPF pinning              : Ok
42.3: BPF prologue generation  : Skip (clang/debuginfo isn't
installed or environment missing BPF support)

Fixes: ba1fae431e74bb42 ("perf test: Add 'perf test BPF'")
Signed-off-by: Kajol Jain <redacted>
Reviewed-by: Madhavan Srinivasan <maddy@linux.ibm.com>
---
tools/perf/tests/bpf.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/tools/perf/tests/bpf.c b/tools/perf/tests/bpf.c
index 17c023823713..57cecadc1da2 100644
--- a/tools/perf/tests/bpf.c
+++ b/tools/perf/tests/bpf.c

@@ -126,6 +126,10 @@ static int do_test(struct bpf_object *obj, int (*func)(void),

	err = parse_events_load_bpf_obj(&parse_state, &parse_state.list, obj, NULL);
	parse_events_error__exit(&parse_error);
+	if (err == -ENOENT) {
+		pr_debug("Failed to add events selected by BPF, debuginfo package not installed\n");
+		return TEST_SKIP;
+	}

Hi Kajol,

Here, you have used ENOENT to skip the test. But there could be other places in the code path for “parse_events_load_bpf_obj”
which also returns ENOENT. In that case, for any exit that returns ENOENT, test will get skipped.

Can we look at the logs, example we have this in commit logs:

	Rebuild with CONFIG_DEBUG_INFO=y, or install an appropriate debuginfo
	package.

so as to decide whether to skip for debug info ?

Kajol?

- Arnaldo
 

Thanks
Athira

quoted

	if (err || list_empty(&parse_state.list)) {
		pr_debug("Failed to add events selected by BPF\n");
		return TEST_FAIL;

@@ -368,7 +372,7 @@ static struct test_case bpf_tests[] = {

			"clang isn't installed or environment missing BPF support"),
#ifdef HAVE_BPF_PROLOGUE
	TEST_CASE_REASON("BPF prologue generation", bpf_prologue_test,
-			"clang isn't installed or environment missing BPF support"),
+			"clang/debuginfo isn't installed or environment missing BPF support"),
#else
	TEST_CASE_REASON("BPF prologue generation", bpf_prologue_test, "not compiled in"),
#endif
-- 
2.31.1