Merge branch 'selftests/bpf: support custom per-test flags and multiple expected messages'

Eduard Zingerman says:

====================

This patch allows to specify program flags and multiple verifier log
messages for the test_loader kind of tests. For example:

  tools/testing/selftets/bpf/progs/foobar.c:

    SEC("tc")
    __success __log_level(7)
    __msg("first message")
    __msg("next message")
    __flag(BPF_F_ANY_ALIGNMENT)
    int buz(struct __sk_buff *skb)
    { ... }

It was developed by Andrii Nakryiko ([1]), I reused it in a
"test_verifier tests migration to inline assembly" patch series ([2]),
but the series is currently stuck on my side.
Andrii asked to spin this particular patch separately ([3]).

[1] https://lore.kernel.org/bpf/CAEf4BzZH0ZxorCi7nPDbRqSK9f+410RooNwNJGwfw8=0a5i1nw@mail.gmail.com/
[2] https://lore.kernel.org/bpf/20230123145148.2791939-1-eddyz87@gmail.com/
[3] https://lore.kernel.org/bpf/20230123145148.2791939-1-eddyz87@gmail.com/T/#m52e806c5a679a2aa8f484d011be7ec105939127a
====================

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>

1 files changed, 23 insertions, 0 deletions

diff --git a/tools/testing/selftests/bpf/progs/bpf_misc.h b/tools/testing/selftests/bpf/progs/bpf_misc.h
index 14e28f991451..f704885aa534 100644
--- a/tools/testing/selftests/bpf/progs/bpf_misc.h
+++ b/tools/testing/selftests/bpf/progs/bpf_misc.h
@@ -2,10 +2,33 @@
 #ifndef __BPF_MISC_H__
 #define __BPF_MISC_H__
 
+/* This set of attributes controls behavior of the
+ * test_loader.c:test_loader__run_subtests().
+ *
+ * __msg             Message expected to be found in the verifier log.
+ *                   Multiple __msg attributes could be specified.
+ *
+ * __success         Expect program load success in privileged mode.
+ *
+ * __failure         Expect program load failure in privileged mode.
+ *
+ * __log_level       Log level to use for the program, numeric value expected.
+ *
+ * __flag            Adds one flag use for the program, the following values are valid:
+ *                   - BPF_F_STRICT_ALIGNMENT;
+ *                   - BPF_F_TEST_RND_HI32;
+ *                   - BPF_F_TEST_STATE_FREQ;
+ *                   - BPF_F_SLEEPABLE;
+ *                   - BPF_F_XDP_HAS_FRAGS;
+ *                   - A numeric value.
+ *                   Multiple __flag attributes could be specified, the final flags
+ *                   value is derived by applying binary "or" to all specified values.
+ */
 #define __msg(msg)		__attribute__((btf_decl_tag("comment:test_expect_msg=" msg)))
 #define __failure		__attribute__((btf_decl_tag("comment:test_expect_failure")))
 #define __success		__attribute__((btf_decl_tag("comment:test_expect_success")))
 #define __log_level(lvl)	__attribute__((btf_decl_tag("comment:test_log_level="#lvl)))
+#define __flag(flag)		__attribute__((btf_decl_tag("comment:test_prog_flags="#flag)))
 
 /* Convenience macro for use with 'asm volatile' blocks */
 #define __naked __attribute__((naked))