selftests/bpf: Split out bpf_verif_scale selftests into multiple tests

Instead of using subtests in bpf_verif_scale selftest, turn each scale
sub-test into its own test. Each subtest is compltely independent and
just reuses a bit of common test running logic, so the conversion is
trivial. For convenience, keep all of BPF verifier scale tests in one
file.

This conversion shaves off a significant amount of time when running
test_progs in parallel mode. E.g., just running scale tests (-t verif_scale):

BEFORE
======
Summary: 24/0 PASSED, 0 SKIPPED, 0 FAILED

real    0m22.894s
user    0m0.012s
sys     0m22.797s

AFTER
=====
Summary: 24/0 PASSED, 0 SKIPPED, 0 FAILED

real    0m12.044s
user    0m0.024s
sys     0m27.869s

Ten second saving right there. test_progs -j is not yet ready to be
turned on by default, unfortunately, and some tests fail almost every
time, but this is a good improvement nevertheless. Ignoring few
failures, here is sequential vs parallel run times when running all
tests now:

SEQUENTIAL
==========
Summary: 206/953 PASSED, 4 SKIPPED, 0 FAILED

real    1m5.625s
user    0m4.211s
sys     0m31.650s

PARALLEL
========
Summary: 204/952 PASSED, 4 SKIPPED, 2 FAILED

real    0m35.550s
user    0m4.998s
sys     0m39.890s
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211022223228.99920-5-andrii@kernel.org

tools/testing/selftests/bpf/prog_tests/bpf_verif_scale.c

@@ -39,82 +39,166 @@ struct scale_test_def {
 	bool fails;
 };
 
-void test_bpf_verif_scale(void)
+static void scale_test(const char *file,
+		       enum bpf_prog_type attach_type,
+		       bool should_fail)
 {
-	struct scale_test_def tests[] = {
-		{ "loop3.o", BPF_PROG_TYPE_RAW_TRACEPOINT, true /* fails */ },
+	libbpf_print_fn_t old_print_fn = NULL;
+	int err;
+
+	if (env.verifier_stats) {
+		test__force_log();
+		old_print_fn = libbpf_set_print(libbpf_debug_print);
+	}
+
+	err = check_load(file, attach_type);
+	if (should_fail)
+		ASSERT_ERR(err, "expect_error");
+	else
+		ASSERT_OK(err, "expect_success");
+
+	if (env.verifier_stats)
+		libbpf_set_print(old_print_fn);
+}
+
+void test_verif_scale1()
+{
+	scale_test("test_verif_scale1.o", BPF_PROG_TYPE_SCHED_CLS, false);
+}
+
+void test_verif_scale2()
+{
+	scale_test("test_verif_scale2.o", BPF_PROG_TYPE_SCHED_CLS, false);
+}
+
+void test_verif_scale3()
+{
+	scale_test("test_verif_scale3.o", BPF_PROG_TYPE_SCHED_CLS, false);
+}
+
+void test_verif_scale_pyperf_global()
+{
+	scale_test("pyperf_global.o", BPF_PROG_TYPE_RAW_TRACEPOINT, false);
+}
 
-		{ "test_verif_scale1.o", BPF_PROG_TYPE_SCHED_CLS },
-		{ "test_verif_scale2.o", BPF_PROG_TYPE_SCHED_CLS },
-		{ "test_verif_scale3.o", BPF_PROG_TYPE_SCHED_CLS },
+void test_verif_scale_pyperf_subprogs()
+{
+	scale_test("pyperf_subprogs.o", BPF_PROG_TYPE_RAW_TRACEPOINT, false);
+}
 
-		{ "pyperf_global.o", BPF_PROG_TYPE_RAW_TRACEPOINT },
-		{ "pyperf_subprogs.o", BPF_PROG_TYPE_RAW_TRACEPOINT },
+void test_verif_scale_pyperf50()
+{
+	/* full unroll by llvm */
+	scale_test("pyperf50.o", BPF_PROG_TYPE_RAW_TRACEPOINT, false);
+}
 
+void test_verif_scale_pyperf100()
+{
 	/* full unroll by llvm */
-		{ "pyperf50.o", BPF_PROG_TYPE_RAW_TRACEPOINT },
-		{ "pyperf100.o", BPF_PROG_TYPE_RAW_TRACEPOINT },
-		{ "pyperf180.o", BPF_PROG_TYPE_RAW_TRACEPOINT },
+	scale_test("pyperf100.o", BPF_PROG_TYPE_RAW_TRACEPOINT, false);
+}
 
+void test_verif_scale_pyperf180()
+{
+	/* full unroll by llvm */
+	scale_test("pyperf180.o", BPF_PROG_TYPE_RAW_TRACEPOINT, false);
+}
+
+void test_verif_scale_pyperf600()
+{
 	/* partial unroll. llvm will unroll loop ~150 times.
 	 * C loop count -> 600.
 	 * Asm loop count -> 4.
 	 * 16k insns in loop body.
 	 * Total of 5 such loops. Total program size ~82k insns.
 	 */
-		{ "pyperf600.o", BPF_PROG_TYPE_RAW_TRACEPOINT },
+	scale_test("pyperf600.o", BPF_PROG_TYPE_RAW_TRACEPOINT, false);
+}
 
+void test_verif_scale_pyperf600_nounroll()
+{
 	/* no unroll at all.
 	 * C loop count -> 600.
 	 * ASM loop count -> 600.
 	 * ~110 insns in loop body.
 	 * Total of 5 such loops. Total program size ~1500 insns.
 	 */
-		{ "pyperf600_nounroll.o", BPF_PROG_TYPE_RAW_TRACEPOINT },
+	scale_test("pyperf600_nounroll.o", BPF_PROG_TYPE_RAW_TRACEPOINT, false);
+}
 
-		{ "loop1.o", BPF_PROG_TYPE_RAW_TRACEPOINT },
-		{ "loop2.o", BPF_PROG_TYPE_RAW_TRACEPOINT },
-		{ "loop4.o", BPF_PROG_TYPE_SCHED_CLS },
-		{ "loop5.o", BPF_PROG_TYPE_SCHED_CLS },
-		{ "loop6.o", BPF_PROG_TYPE_KPROBE },
+void test_verif_scale_loop1()
+{
+	scale_test("loop1.o", BPF_PROG_TYPE_RAW_TRACEPOINT, false);
+}
 
+void test_verif_scale_loop2()
+{
+	scale_test("loop2.o", BPF_PROG_TYPE_RAW_TRACEPOINT, false);
+}
+
+void test_verif_scale_loop3_fail()
+{
+	scale_test("loop3.o", BPF_PROG_TYPE_RAW_TRACEPOINT, true /* fails */);
+}
+
+void test_verif_scale_loop4()
+{
+	scale_test("loop4.o", BPF_PROG_TYPE_SCHED_CLS, false);
+}
+
+void test_verif_scale_loop5()
+{
+	scale_test("loop5.o", BPF_PROG_TYPE_SCHED_CLS, false);
+}
+
+void test_verif_scale_loop6()
+{
+	scale_test("loop6.o", BPF_PROG_TYPE_KPROBE, false);
+}
+
+void test_verif_scale_strobemeta()
+{
 	/* partial unroll. 19k insn in a loop.
 	 * Total program size 20.8k insn.
 	 * ~350k processed_insns
 	 */
-		{ "strobemeta.o", BPF_PROG_TYPE_RAW_TRACEPOINT },
+	scale_test("strobemeta.o", BPF_PROG_TYPE_RAW_TRACEPOINT, false);
+}
 
+void test_verif_scale_strobemeta_nounroll1()
+{
 	/* no unroll, tiny loops */
-		{ "strobemeta_nounroll1.o", BPF_PROG_TYPE_RAW_TRACEPOINT },
-		{ "strobemeta_nounroll2.o", BPF_PROG_TYPE_RAW_TRACEPOINT },
-
-		/* non-inlined subprogs */
-		{ "strobemeta_subprogs.o", BPF_PROG_TYPE_RAW_TRACEPOINT },
-
-		{ "test_sysctl_loop1.o", BPF_PROG_TYPE_CGROUP_SYSCTL },
-		{ "test_sysctl_loop2.o", BPF_PROG_TYPE_CGROUP_SYSCTL },
+	scale_test("strobemeta_nounroll1.o", BPF_PROG_TYPE_RAW_TRACEPOINT, false);
+}
 
-		{ "test_xdp_loop.o", BPF_PROG_TYPE_XDP },
-		{ "test_seg6_loop.o", BPF_PROG_TYPE_LWT_SEG6LOCAL },
-	};
-	libbpf_print_fn_t old_print_fn = NULL;
-	int err, i;
+void test_verif_scale_strobemeta_nounroll2()
+{
+	/* no unroll, tiny loops */
+	scale_test("strobemeta_nounroll2.o", BPF_PROG_TYPE_RAW_TRACEPOINT, false);
+}
 
-	if (env.verifier_stats) {
-		test__force_log();
-		old_print_fn = libbpf_set_print(libbpf_debug_print);
-	}
+void test_verif_scale_strobemeta_subprogs()
+{
+	/* non-inlined subprogs */
+	scale_test("strobemeta_subprogs.o", BPF_PROG_TYPE_RAW_TRACEPOINT, false);
+}
 
-	for (i = 0; i < ARRAY_SIZE(tests); i++) {
-		const struct scale_test_def *test = &tests[i];
+void test_verif_scale_sysctl_loop1()
+{
+	scale_test("test_sysctl_loop1.o", BPF_PROG_TYPE_CGROUP_SYSCTL, false);
+}
 
-		if (!test__start_subtest(test->file))
-			continue;
+void test_verif_scale_sysctl_loop2()
+{
+	scale_test("test_sysctl_loop2.o", BPF_PROG_TYPE_CGROUP_SYSCTL, false);
+}
 
-		err = check_load(test->file, test->attach_type);
-		CHECK_FAIL(err && !test->fails);
-	}
+void test_verif_scale_xdp_loop()
+{
+	scale_test("test_xdp_loop.o", BPF_PROG_TYPE_XDP, false);
+}
 
-	if (env.verifier_stats)
-		libbpf_set_print(old_print_fn);
+void test_verif_scale_seg6_loop()
+{
+	scale_test("test_seg6_loop.o", BPF_PROG_TYPE_LWT_SEG6LOCAL, false);
 }