selftests/bpf: add tests for sleepable (uk)probes

Add tests that ensure sleepable uprobe programs work correctly.
Add tests that ensure sleepable kprobe programs cannot attach.

Also add tests that attach both sleepable and non-sleepable
uprobe programs to the same location (i.e. same bpf_prog_array).

Acked-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Delyan Kratunov <delyank@fb.com>
Link: https://lore.kernel.org/r/c744e5bb7a5c0703f05444dc41f2522ba3579a48.1655248076.git.delyank@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

1 files changed, 48 insertions, 1 deletions

diff --git a/tools/testing/selftests/bpf/prog_tests/attach_probe.c b/tools/testing/selftests/bpf/prog_tests/attach_probe.c
index 08c0601b3e84..0b899d2d8ea7 100644
--- a/tools/testing/selftests/bpf/prog_tests/attach_probe.c
+++ b/tools/testing/selftests/bpf/prog_tests/attach_probe.c
@@ -17,6 +17,14 @@ static void trigger_func2(void)
 	asm volatile ("");
 }
 
+/* attach point for byname sleepable uprobe */
+static void trigger_func3(void)
+{
+	asm volatile ("");
+}
+
+static char test_data[] = "test_data";
+
 void test_attach_probe(void)
 {
 	DECLARE_LIBBPF_OPTS(bpf_uprobe_opts, uprobe_opts);
@@ -49,9 +57,17 @@ void test_attach_probe(void)
 	if (!ASSERT_GE(ref_ctr_offset, 0, "ref_ctr_offset"))
 		return;
 
-	skel = test_attach_probe__open_and_load();
+	skel = test_attach_probe__open();
 	if (!ASSERT_OK_PTR(skel, "skel_open"))
 		return;
+
+	/* sleepable kprobe test case needs flags set before loading */
+	if (!ASSERT_OK(bpf_program__set_flags(skel->progs.handle_kprobe_sleepable,
+		BPF_F_SLEEPABLE), "kprobe_sleepable_flags"))
+		goto cleanup;
+
+	if (!ASSERT_OK(test_attach_probe__load(skel), "skel_load"))
+		goto cleanup;
 	if (!ASSERT_OK_PTR(skel->bss, "check_bss"))
 		goto cleanup;
 
@@ -151,6 +167,30 @@ void test_attach_probe(void)
 	if (!ASSERT_OK_PTR(skel->links.handle_uretprobe_byname2, "attach_uretprobe_byname2"))
 		goto cleanup;
 
+	/* sleepable kprobes should not attach successfully */
+	skel->links.handle_kprobe_sleepable = bpf_program__attach(skel->progs.handle_kprobe_sleepable);
+	if (!ASSERT_ERR_PTR(skel->links.handle_kprobe_sleepable, "attach_kprobe_sleepable"))
+		goto cleanup;
+
+	/* test sleepable uprobe and uretprobe variants */
+	skel->links.handle_uprobe_byname3_sleepable = bpf_program__attach(skel->progs.handle_uprobe_byname3_sleepable);
+	if (!ASSERT_OK_PTR(skel->links.handle_uprobe_byname3_sleepable, "attach_uprobe_byname3_sleepable"))
+		goto cleanup;
+
+	skel->links.handle_uprobe_byname3 = bpf_program__attach(skel->progs.handle_uprobe_byname3);
+	if (!ASSERT_OK_PTR(skel->links.handle_uprobe_byname3, "attach_uprobe_byname3"))
+		goto cleanup;
+
+	skel->links.handle_uretprobe_byname3_sleepable = bpf_program__attach(skel->progs.handle_uretprobe_byname3_sleepable);
+	if (!ASSERT_OK_PTR(skel->links.handle_uretprobe_byname3_sleepable, "attach_uretprobe_byname3_sleepable"))
+		goto cleanup;
+
+	skel->links.handle_uretprobe_byname3 = bpf_program__attach(skel->progs.handle_uretprobe_byname3);
+	if (!ASSERT_OK_PTR(skel->links.handle_uretprobe_byname3, "attach_uretprobe_byname3"))
+		goto cleanup;
+
+	skel->bss->user_ptr = test_data;
+
 	/* trigger & validate kprobe && kretprobe */
 	usleep(1);
 
@@ -164,6 +204,9 @@ void test_attach_probe(void)
 	/* trigger & validate uprobe attached by name */
 	trigger_func2();
 
+	/* trigger & validate sleepable uprobe attached by name */
+	trigger_func3();
+
 	ASSERT_EQ(skel->bss->kprobe_res, 1, "check_kprobe_res");
 	ASSERT_EQ(skel->bss->kprobe2_res, 11, "check_kprobe_auto_res");
 	ASSERT_EQ(skel->bss->kretprobe_res, 2, "check_kretprobe_res");
@@ -174,6 +217,10 @@ void test_attach_probe(void)
 	ASSERT_EQ(skel->bss->uretprobe_byname_res, 6, "check_uretprobe_byname_res");
 	ASSERT_EQ(skel->bss->uprobe_byname2_res, 7, "check_uprobe_byname2_res");
 	ASSERT_EQ(skel->bss->uretprobe_byname2_res, 8, "check_uretprobe_byname2_res");
+	ASSERT_EQ(skel->bss->uprobe_byname3_sleepable_res, 9, "check_uprobe_byname3_sleepable_res");
+	ASSERT_EQ(skel->bss->uprobe_byname3_res, 10, "check_uprobe_byname3_res");
+	ASSERT_EQ(skel->bss->uretprobe_byname3_sleepable_res, 11, "check_uretprobe_byname3_sleepable_res");
+	ASSERT_EQ(skel->bss->uretprobe_byname3_res, 12, "check_uretprobe_byname3_res");
 
 cleanup:
 	test_attach_probe__destroy(skel);