selftests/bpf: Deduplicate write_sysctl() to test_progs.c

This helper is needed in multiple tests. Instead of copying it over
and over, better to deduplicate this helper to test_progs.c.

test_progs.c is chosen over testing_helpers.c because of this helper's
use of CHECK / ASSERT_*, and the CHECK was modified to use ASSERT_*
so it does not rely on a duration variable.

Suggested-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: YiFei Zhu <zhuyifei@google.com>
Link: https://lore.kernel.org/r/9b4fc9a27bd52f771b657b4c4090fc8d61f3a6b5.1662682323.git.zhuyifei@google.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>

1 files changed, 0 insertions, 20 deletions

diff --git a/tools/testing/selftests/bpf/prog_tests/tcp_hdr_options.c b/tools/testing/selftests/bpf/prog_tests/tcp_hdr_options.c
index 1fa772079967..f24436d33cd6 100644
--- a/tools/testing/selftests/bpf/prog_tests/tcp_hdr_options.c
+++ b/tools/testing/selftests/bpf/prog_tests/tcp_hdr_options.c
@@ -54,26 +54,6 @@ static int create_netns(void)
 	return 0;
 }
 
-static int write_sysctl(const char *sysctl, const char *value)
-{
-	int fd, err, len;
-
-	fd = open(sysctl, O_WRONLY);
-	if (CHECK(fd == -1, "open sysctl", "open(%s): %s (%d)\n",
-		  sysctl, strerror(errno), errno))
-		return -1;
-
-	len = strlen(value);
-	err = write(fd, value, len);
-	close(fd);
-	if (CHECK(err != len, "write sysctl",
-		  "write(%s, %s): err:%d %s (%d)\n",
-		  sysctl, value, err, strerror(errno), errno))
-		return -1;
-
-	return 0;
-}
-
 static void print_hdr_stg(const struct hdr_stg *hdr_stg, const char *prefix)
 {
 	fprintf(stderr, "%s{active:%u, resend_syn:%u, syncookie:%u, fastopen:%u}\n",