[PATCH v7 0/7] selftests/mm: skip several tests when thp is not available

[PATCH v7 0/7] selftests/mm: skip several tests when thp is not available

[Chunyu Hu]

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.

Changes in v7:
  - patch 1 add reviewed-by from Lorenzo
  - patch 4 new patch to make ksft_exit_fail_perror variable length
    arguments
  - patch 5 change to use %.*s to print the buf when error happened
    Limit the buflen arg as 2 minimum. Check the error path (numwritten
	< 0).
    And use the ksft_exit_fail_perror to print the logs in error path

Chagnes in v6:
  - patch 3 add reviewed-by from Lorenzo
  - patch 4 handle the errno before and after close(), suggested by AI

Changes in v5:
  - patch 1, patch 3 updated reviwed-by and acked-by
  - patch 4 adds new patch for robust write_file()

Changes in v4:
  - patch 1 update to use thp_available instead of thp_is_enabled,
    suggested by ai review
  - removed reviewed-by and acked-by

Changes in v3:
  - patch 1 update commit message to show the log snippet with where the
    fail happens, change the 'false positive' to 'false negative'.
    Update reviwed by
  - patch 2 update reviewed-by
  - patch 3 make write_file to void return
  - patch 4 and patch 5 updated reviewed-by/acked-by

Changes in v2:
  - replace 'false postive' with 'false negative' in cover letter
  - patch 1 and patch 2 add reviewed-by/acked-by
  - new patch 3 to add write_file() in vm_util as a common helper
  - patch 4 removed the {} in if block, removed the write_file helper
    rename chunk in v1. Add reviewed-by
  - patch 5 move the exit chunk to the front of ksft_print_headers() as
    suggested by David.  Add review by.

Chunyu Hu (7):
  selftests/mm/guard-regions: skip collapse test when thp not enabled
  selftests/mm: soft-dirty: skip two tests when thp is not available
  selftests/mm: move write_file helper to vm_util
  kselftest: make ksft_exit_fail_perror support va args
  selftests/mm/vm_util: robust write_file()
  selftests/mm: split_huge_page_test: skip the test when thp is not
    available
  selftests/mm: transhuge_stress: skip the test when thp not available

 tools/testing/selftests/kselftest.h           | 21 +++++++++--
 tools/testing/selftests/mm/guard-regions.c    |  4 +++
 tools/testing/selftests/mm/soft-dirty.c       |  4 ++-
 .../selftests/mm/split_huge_page_test.c       | 19 +++-------
 tools/testing/selftests/mm/thp_settings.c     | 35 ++-----------------
 tools/testing/selftests/mm/thp_settings.h     |  1 -
 tools/testing/selftests/mm/transhuge-stress.c |  4 +++
 tools/testing/selftests/mm/vm_util.c          | 24 +++++++++++++
 tools/testing/selftests/mm/vm_util.h          |  2 ++
 9 files changed, 62 insertions(+), 52 deletions(-)


base-commit: 7aaa8047eafd0bd628065b15757d9b48c5f9c07d
-- 
2.53.0

[PATCH v7 0/7] selftests/mm: skip several tests when thp is not available

[Chunyu Hu]

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.

Changes in v7:
  - patch 1 add reviewed-by from Lorenzo
  - patch 4 new patch to make ksft_exit_fail_perror variable length
    arguments
  - patch 5 change to use %.*s to print the buf when error happened
    Limit the buflen arg as 2 minimum. Check the error path (numwritten
	< 0).
    And use the ksft_exit_fail_perror to print the logs in error path

Chagnes in v6:
  - patch 3 add reviewed-by from Lorenzo
  - patch 4 handle the errno before and after close(), suggested by AI

Changes in v5:
  - patch 1, patch 3 updated reviwed-by and acked-by
  - patch 4 adds new patch for robust write_file()

Changes in v4:
  - patch 1 update to use thp_available instead of thp_is_enabled,
    suggested by ai review
  - removed reviewed-by and acked-by

Changes in v3:
  - patch 1 update commit message to show the log snippet with where the
    fail happens, change the 'false positive' to 'false negative'.
    Update reviwed by
  - patch 2 update reviewed-by
  - patch 3 make write_file to void return
  - patch 4 and patch 5 updated reviewed-by/acked-by

Changes in v2:
  - replace 'false postive' with 'false negative' in cover letter
  - patch 1 and patch 2 add reviewed-by/acked-by
  - new patch 3 to add write_file() in vm_util as a common helper
  - patch 4 removed the {} in if block, removed the write_file helper
    rename chunk in v1. Add reviewed-by
  - patch 5 move the exit chunk to the front of ksft_print_headers() as
    suggested by David.  Add review by.

Chunyu Hu (7):
  selftests/mm/guard-regions: skip collapse test when thp not enabled
  selftests/mm: soft-dirty: skip two tests when thp is not available
  selftests/mm: move write_file helper to vm_util
  kselftest: make ksft_exit_fail_perror support va args
  selftests/mm/vm_util: robust write_file()
  selftests/mm: split_huge_page_test: skip the test when thp is not
    available
  selftests/mm: transhuge_stress: skip the test when thp not available

 tools/testing/selftests/kselftest.h           | 21 +++++++++--
 tools/testing/selftests/mm/guard-regions.c    |  4 +++
 tools/testing/selftests/mm/soft-dirty.c       |  4 ++-
 .../selftests/mm/split_huge_page_test.c       | 19 +++-------
 tools/testing/selftests/mm/thp_settings.c     | 35 ++-----------------
 tools/testing/selftests/mm/thp_settings.h     |  1 -
 tools/testing/selftests/mm/transhuge-stress.c |  4 +++
 tools/testing/selftests/mm/vm_util.c          | 24 +++++++++++++
 tools/testing/selftests/mm/vm_util.h          |  2 ++
 9 files changed, 62 insertions(+), 52 deletions(-)


base-commit: 7aaa8047eafd0bd628065b15757d9b48c5f9c07d
-- 
2.53.0

Re: [PATCH v7 0/7] selftests/mm: skip several tests when thp is not available

[Andrew Morton]

On Mon, 30 Mar 2026 23:14:56 +0800 Chunyu Hu <chuhu@redhat.com> 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 v7:
>   - patch 1 add reviewed-by from Lorenzo
>   - patch 4 new patch to make ksft_exit_fail_perror variable length
>     arguments
>   - patch 5 change to use %.*s to print the buf when error happened
>     Limit the buflen arg as 2 minimum. Check the error path (numwritten
> 	< 0).
>     And use the ksft_exit_fail_perror to print the logs in error path

Here's how v7 altered mm.git.


 tools/testing/selftests/kselftest.h  |   21 ++++++++++++++++++---
 tools/testing/selftests/mm/vm_util.c |   14 +++++++-------
 2 files changed, 25 insertions(+), 10 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(msg);
+ *    ksft_exit_fail_perror(fmt, ...);
  *
  */
 #ifndef __KSELFTEST_H
@@ -417,9 +417,24 @@ static inline __noreturn __printf(1, 2)
 	exit(KSFT_FAIL);
 }
 
-static inline __noreturn void ksft_exit_fail_perror(const char *msg)
+static inline __noreturn __printf(1, 2) void ksft_exit_fail_perror(const char *msg, ...)
 {
-	ksft_exit_fail_msg("%s: %s (%d)\n", msg, strerror(errno), errno);
+	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);
 }
 
 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
@@ -782,21 +782,21 @@ void write_file(const char *path, const
 	int fd, saved_errno;
 	ssize_t numwritten;
 
-	if (buflen < 1)
+	if (buflen < 2)
 		ksft_exit_fail_msg("Incorrect buffer len: %zu\n", buflen);
 
 	fd = open(path, O_WRONLY);
 	if (fd == -1)
-		ksft_exit_fail_msg("%s open failed: %s\n", path, strerror(errno));
+		ksft_exit_fail_perror("%s open failed", path);
 
 	numwritten = write(fd, buf, buflen - 1);
 	saved_errno = errno;
 	close(fd);
 	errno = saved_errno;
-	if (numwritten < 1)
-		ksft_exit_fail_msg("%s write(%s) failed: %s\n", path, buf,
-				strerror(errno));
+	if (numwritten < 0)
+		ksft_exit_fail_perror("%s write(%.*s) failed", path, (int)(buflen - 1),
+				buf);
 	if (numwritten != buflen - 1)
-		ksft_exit_fail_msg("%s write(%s) is truncated, expected %zu bytes, got %zd bytes\n",
-				path, buf, buflen - 1, numwritten);
+		ksft_exit_fail_msg("%s write(%.*s) is truncated, expected %zu bytes, got %zd bytes\n",
+				path, (int)(buflen - 1), buf, buflen - 1, numwritten);
 }
_