[PATCH bpf-next] selftests/bpf: restore original comm in test_overhead
From: Stanislav Fomichev <hidden>
Date: 2020-01-08 19:21:36
Also in:
bpf
Subsystem:
bpf [general] (safe dynamic programs and tools), bpf [selftests] (test runners & infrastructure), kernel selftest framework, the rest · Maintainers:
Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Eduard Zingerman, Kumar Kartikeya Dwivedi, Shuah Khan, Shuah Khan, Linus Torvalds
test_overhead changes task comm in order to estimate BPF trampoline overhead but never sets the comm back to the original one. We have the tests (like core_reloc.c) that have 'test_progs' as hard-coded expected comm, so let's try to preserve the original comm. Currently, everything works because the order of execution is: first core_recloc, then test_overhead; but let's make it a bit future-proof. Other related changes: use 'test_overhead' as new comm instead of 'test' to make it easy to debug and drop '\n' at the end. Signed-off-by: Stanislav Fomichev <redacted> --- tools/testing/selftests/bpf/prog_tests/test_overhead.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-)
diff --git a/tools/testing/selftests/bpf/prog_tests/test_overhead.c b/tools/testing/selftests/bpf/prog_tests/test_overhead.c
index c32aa28bd93f..465b371a561d 100644
--- a/tools/testing/selftests/bpf/prog_tests/test_overhead.c
+++ b/tools/testing/selftests/bpf/prog_tests/test_overhead.c@@ -2,6 +2,7 @@ /* Copyright (c) 2019 Facebook */ #define _GNU_SOURCE #include <sched.h> +#include <sys/prctl.h> #include <test_progs.h> #define MAX_CNT 100000
@@ -17,7 +18,7 @@ static __u64 time_get_ns(void) static int test_task_rename(const char *prog) { int i, fd, duration = 0, err; - char buf[] = "test\n"; + char buf[] = "test_overhead"; __u64 start_time; fd = open("/proc/self/comm", O_WRONLY|O_TRUNC);
@@ -66,6 +67,10 @@ void test_test_overhead(void) struct bpf_object *obj; struct bpf_link *link; int err, duration = 0; + char comm[16] = {}; + + if (CHECK_FAIL(prctl(PR_GET_NAME, comm, 0L, 0L, 0L))) + return; obj = bpf_object__open_file("./test_overhead.o", NULL); if (CHECK(IS_ERR(obj), "obj_open_file", "err %ld\n", PTR_ERR(obj)))
@@ -138,5 +143,6 @@ void test_test_overhead(void) test_run("fexit"); bpf_link__destroy(link); cleanup: + prctl(PR_SET_NAME, comm, 0L, 0L, 0L); bpf_object__close(obj); }
--
2.24.1.735.g03f4e72817-goog