selftests/bpf: add sub-tests support for test_progs

Allow tests to have their own set of sub-tests. Also add ability to do
test/subtest selection using `-t <test-name>/<subtest-name>` and `-n
<test-nums-set>/<subtest-nums-set>`, as an extension of existing -t/-n
selector options. For the <test-num-set> format: it's a comma-separated
list of either individual test numbers (1-based), or range of test
numbers. E.g., all of the following are valid sets of test numbers:
  - 10
  - 1,2,3
  - 1-3
  - 5-10,1,3-4

'/<subtest' part is optional, but has the same format. E.g., to select
test #3 and its sub-tests #10 through #15, use: -t 3/10-15.

Similarly, to select tests by name, use `-t verif/strobe`:

  $ sudo ./test_progs -t verif/strobe
  #3/12 strobemeta.o:OK
  #3/13 strobemeta_nounroll1.o:OK
  #3/14 strobemeta_nounroll2.o:OK
  #3 bpf_verif_scale:OK
  Summary: 1/3 PASSED, 0 FAILED

Example of using subtest API is in the next patch, converting
bpf_verif_scale.c tests to use sub-tests.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

1 files changed, 12 insertions, 4 deletions

diff --git a/tools/testing/selftests/bpf/test_progs.h b/tools/testing/selftests/bpf/test_progs.h
index 62f55a4231e9..afd14962456f 100644
--- a/tools/testing/selftests/bpf/test_progs.h
+++ b/tools/testing/selftests/bpf/test_progs.h
@@ -40,9 +40,15 @@ typedef __u16 __sum16;
 
 struct prog_test_def;
 
+struct test_selector {
+	const char *name;
+	bool *num_set;
+	int num_set_len;
+};
+
 struct test_env {
-	int test_num_selector;
-	const char *test_name_selector;
+	struct test_selector test_selector;
+	struct test_selector subtest_selector;
 	bool verifier_stats;
 	bool verbose;
 	bool very_verbose;
@@ -54,8 +60,9 @@ struct test_env {
 	size_t log_cnt;
 	size_t log_cap;
 
-	int succ_cnt;
-	int fail_cnt;
+	int succ_cnt; /* successful tests */
+	int sub_succ_cnt; /* successful sub-tests */
+	int fail_cnt; /* total failed tests + sub-tests */
 };
 
 extern int error_cnt;
@@ -65,6 +72,7 @@ extern struct test_env env;
 extern void test__printf(const char *fmt, ...);
 extern void test__vprintf(const char *fmt, va_list args);
 extern void test__force_log();
+extern bool test__start_subtest(const char *name);
 
 #define MAGIC_BYTES 123