Re: [PATCH v8 0/6] selftests/mm: skip several tests when thp is not available

[Andrew Morton]

On Thu,  2 Apr 2026 09:45:37 +0800 Chunyu Hu <chuhu@xxxxxxxxxx> wrote:

> There are several tests requires transprarent hugepages, when run on thp
> disabled kernel such as realtime kernel, there will be false negative.
> Mark those tests as skip when thp is not available.

Thanks, I updated mm.git's mm-unstable branch to this version.

> Changes in v8:
>   - removed the patch 4 in v7 (make ksft_exit_fail_perror variable length)
>     as no clean way to do it at the moment and ksft_exit_fail_msg could
>     do by printing an extra strerror param.
>   - patch 4 use ksft_exit_fail_msg instead of ksft_exit_fail_perror  

Below is how v8 altered mm.git:


 tools/testing/selftests/kselftest.h  |   21 +++------------------
 tools/testing/selftests/mm/vm_util.c |    6 +++---
 2 files changed, 6 insertions(+), 21 deletions(-)

--- a/tools/testing/selftests/kselftest.h~b
+++ a/tools/testing/selftests/kselftest.h
@@ -43,7 +43,7 @@
  * the program is aborting before finishing all tests):
  *
  *    ksft_exit_fail_msg(fmt, ...);
- *    ksft_exit_fail_perror(fmt, ...);
+ *    ksft_exit_fail_perror(msg);
  *
  */
 #ifndef __KSELFTEST_H
@@ -417,24 +417,9 @@ static inline __noreturn __printf(1, 2)
 	exit(KSFT_FAIL);
 }
 
-static inline __noreturn __printf(1, 2) void ksft_exit_fail_perror(const char *msg, ...)
+static inline __noreturn void ksft_exit_fail_perror(const char *msg)
 {
-	va_list args;
-	char *buf = NULL;
-	int saved_errno = errno;
-
-	va_start(args, msg);
-	if (vasprintf(&buf, msg, args) == -1) {
-		va_end(args);
-		ksft_exit_fail_msg("vasprintf failed: %s (%d)\n", strerror(saved_errno),
-				saved_errno);
-	}
-	va_end(args);
-
-	errno = saved_errno;
-	ksft_exit_fail_msg("%s: %s (%d)\n", buf, strerror(errno), errno);
-
-	free(buf);
+	ksft_exit_fail_msg("%s: %s (%d)\n", msg, strerror(errno), errno);
 }
 
 static inline __noreturn void ksft_exit_xfail(void)
--- a/tools/testing/selftests/mm/vm_util.c~b
+++ a/tools/testing/selftests/mm/vm_util.c
@@ -775,15 +775,15 @@ void write_file(const char *path, const
 
 	fd = open(path, O_WRONLY);
 	if (fd == -1)
-		ksft_exit_fail_perror("%s open failed", path);
+		ksft_exit_fail_msg("%s open failed: %s\n", path, strerror(errno));
 
 	numwritten = write(fd, buf, buflen - 1);
 	saved_errno = errno;
 	close(fd);
 	errno = saved_errno;
 	if (numwritten < 0)
-		ksft_exit_fail_perror("%s write(%.*s) failed", path, (int)(buflen - 1),
-				buf);
+		ksft_exit_fail_msg("%s write(%.*s) failed: %s\n", path, (int)(buflen - 1),
+				buf, strerror(errno));
 	if (numwritten != buflen - 1)
 		ksft_exit_fail_msg("%s write(%.*s) is truncated, expected %zu bytes, got %zd bytes\n",
 				path, (int)(buflen - 1), buf, buflen - 1, numwritten);
_