[PATCH bpf-next v9 23/23] selftests/bpf: Load an exception cleanup program from a light skeleton

[Yonghong Song <yonghong.song@linux.dev>]

A light skeleton loads a program by a path of its own: its loader
program builds the attr and resolves kfunc names when it runs. Build
progs/exceptions_cleanup.c as a light skeleton too, and run the case in
which every pad runs: a table that lost records or came out at the wrong
offsets would fail to load, or run the wrong pads.

Signed-off-by: Yonghong Song <yonghong.song@linux.dev>
---
 tools/testing/selftests/bpf/Makefile.skel     |  2 +-
 .../bpf/prog_tests/exceptions_cleanup.c       | 31 +++++++++++++++++++
 2 files changed, 32 insertions(+), 1 deletion(-)

diff --git a/tools/testing/selftests/bpf/Makefile.skel b/tools/testing/selftests/bpf/Makefile.skel
index 06e297a17156..d9cbe8ac85b7 100644
--- a/tools/testing/selftests/bpf/Makefile.skel
+++ b/tools/testing/selftests/bpf/Makefile.skel
@@ -40,7 +40,7 @@ LSKELS_SIGNED := fentry_test.c fexit_test.c atomics.c
 
 # Generate both light skeleton and libbpf skeleton for these
 LSKELS_EXTRA := test_ksyms_module.c test_ksyms_weak.c kfunc_call_test.c \
-	kfunc_call_test_subprog.c test_global_percpu_data.c
+	kfunc_call_test_subprog.c test_global_percpu_data.c exceptions_cleanup.c
 SKEL_BLACKLIST += $(LSKELS) $(LSKELS_SIGNED)
 
 test_static_linked.skel.h-deps := test_static_linked1.bpf.o test_static_linked2.bpf.o
diff --git a/tools/testing/selftests/bpf/prog_tests/exceptions_cleanup.c b/tools/testing/selftests/bpf/prog_tests/exceptions_cleanup.c
index 7c5dffd4b861..1493c3efa599 100644
--- a/tools/testing/selftests/bpf/prog_tests/exceptions_cleanup.c
+++ b/tools/testing/selftests/bpf/prog_tests/exceptions_cleanup.c
@@ -6,6 +6,7 @@
 #include "exceptions_cleanup_fail.skel.h"
 #include "exceptions_cleanup_shapes.skel.h"
 #include "exceptions_cleanup_tracing.skel.h"
+#include "exceptions_cleanup.lskel.h"
 
 /* foo3 unwound: every frame that has a pad ran it. */
 #define PADS_FOO3_UNWOUND \
@@ -63,6 +64,33 @@ static int load_tracer(struct exceptions_cleanup *tgt, bool fexit)
 	return err;
 }
 
+static void test_light_skeleton(void)
+{
+	struct exceptions_cleanup_lskel *skel;
+	__u64 ctx = 0;
+	int err;
+
+	LIBBPF_OPTS(bpf_test_run_opts, topts,
+		    .ctx_in = &ctx,
+		    .ctx_size_in = sizeof(ctx),
+	);
+
+	skel = exceptions_cleanup_lskel__open_and_load();
+	if (!ASSERT_OK_PTR(skel, "light open_and_load"))
+		return;
+
+	/* foo3 unwinds, so every pad runs: the whole table has to arrive. */
+	skel->bss->input = 101;
+	err = bpf_prog_test_run_opts(skel->progs.entry.prog_fd, &topts);
+	if (!ASSERT_OK(err, "run"))
+		goto out;
+	ASSERT_EQ(topts.retval, 0, "retval");
+	ASSERT_EQ(skel->bss->pads_ran, PADS_FOO3_UNWOUND | RAN_BUMP,
+		  "pads_ran");
+out:
+	exceptions_cleanup_lskel__destroy(skel);
+}
+
 void test_exceptions_cleanup(void)
 {
 	char log[8192] = {};
@@ -113,6 +141,9 @@ void test_exceptions_cleanup(void)
 
 	exceptions_cleanup__destroy(skel);
 
+	if (test__start_subtest("light_skeleton"))
+		test_light_skeleton();
+
 	RUN_TESTS(exceptions_cleanup_fail);
 	RUN_TESTS(exceptions_cleanup_shapes);
 }
-- 
2.53.0-Meta