When running mincore test cases, I encountered the following failures:
"
mincore_selftest.c:359:check_tmpfs_mmap:Expected ra_pages (511) == 0 (0)
mincore_selftest.c:360:check_tmpfs_mmap:Read-ahead pages found in memory
check_tmpfs_mmap: Test terminated by assertion
FAIL global.check_tmpfs_mmap
not ok 5 global.check_tmpfs_mmap
FAILED: 4 / 5 tests passed
"
The reason for the test case failure is that my system automatically enabled
tmpfs large folio allocation by adding the 'transparent_hugepage_tmpfs=always'
cmdline. However, the test case still expects the tmpfs mounted on /dev/shm to
allocate small folios, which leads to assertion failures when verifying readahead
pages.
To fix this issue, remount tmpfs to a new test directory and set the 'huge=never'
parameter to avoid allocating large folios, which can pass the test.
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
---
.../selftests/mincore/mincore_selftest.c | 25 +++++++++++++++++--
1 file changed, 23 insertions(+), 2 deletions(-)
diff --git a/tools/testing/selftests/mincore/mincore_selftest.c b/tools/testing/selftests/mincore/mincore_selftest.c
index e949a43a6145..e8d7a3a4739f 100644
--- a/tools/testing/selftests/mincore/mincore_selftest.c
+++ b/tools/testing/selftests/mincore/mincore_selftest.c
@@ -12,6 +12,7 @@
#include <unistd.h>
#include <stdlib.h>
#include <sys/mman.h>
+#include <sys/mount.h>
#include <string.h>
#include <fcntl.h>
@@ -283,7 +284,7 @@ TEST(check_file_mmap)
free(vec);
}
-
+#define INPUT_MAX 80
/*
* Test mincore() behavior on a page backed by a tmpfs file. This test
* performs the same steps as the previous one. However, we don't expect
@@ -291,6 +292,9 @@ TEST(check_file_mmap)
*/
TEST(check_tmpfs_mmap)
{
+ char tmpfs_template[] = "/tmp/check_tmpfs_XXXXXX";
+ const char *tmpfs_loc = mkdtemp(tmpfs_template);
+ char testfile[INPUT_MAX];
unsigned char *vec;
int vec_size;
char *addr;
@@ -300,6 +304,10 @@ TEST(check_tmpfs_mmap)
int i;
int ra_pages = 0;
+ ASSERT_NE(NULL, tmpfs_loc) {
+ TH_LOG("Can't mkdir tmpfs dentry\n");
+ }
+
page_size = sysconf(_SC_PAGESIZE);
vec_size = FILE_SIZE / page_size;
if (FILE_SIZE % page_size)
@@ -311,7 +319,18 @@ TEST(check_tmpfs_mmap)
}
errno = 0;
- fd = open("/dev/shm", O_TMPFILE | O_RDWR, 0600);
+ /* Do not use large folios for tmpfs mincore testing */
+ retval = mount("tmpfs", tmpfs_loc, "tmpfs", 0, "huge=never,size=4M");
+ ASSERT_EQ(0, retval) {
+ TH_LOG("Unable to mount tmpfs for testing\n");
+ }
+
+ retval = snprintf(testfile, INPUT_MAX, "%s/test_file", tmpfs_loc);
+ ASSERT_GE(INPUT_MAX, retval) {
+ TH_LOG("Unable to create a tmpfs for testing\n");
+ }
+
+ fd = open(testfile, O_CREAT|O_RDWR, 0664);
ASSERT_NE(-1, fd) {
TH_LOG("Can't create temporary file: %s",
strerror(errno));
@@ -363,6 +382,8 @@ TEST(check_tmpfs_mmap)
munmap(addr, FILE_SIZE);
close(fd);
free(vec);
+ umount(tmpfs_loc);
+ rmdir(tmpfs_loc);
}
TEST_HARNESS_MAIN
--
2.43.5On 26.03.25 04:38, Baolin Wang wrote:
> When running mincore test cases, I encountered the following failures:
>
> "
> mincore_selftest.c:359:check_tmpfs_mmap:Expected ra_pages (511) == 0 (0)
> mincore_selftest.c:360:check_tmpfs_mmap:Read-ahead pages found in memory
> check_tmpfs_mmap: Test terminated by assertion
> FAIL global.check_tmpfs_mmap
> not ok 5 global.check_tmpfs_mmap
> FAILED: 4 / 5 tests passed
> "
>
> The reason for the test case failure is that my system automatically enabled
> tmpfs large folio allocation by adding the 'transparent_hugepage_tmpfs=always'
> cmdline. However, the test case still expects the tmpfs mounted on /dev/shm to
> allocate small folios, which leads to assertion failures when verifying readahead
> pages.
>
> To fix this issue, remount tmpfs to a new test directory and set the 'huge=never'
> parameter to avoid allocating large folios, which can pass the test.
>
> Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
> ---
> .../selftests/mincore/mincore_selftest.c | 25 +++++++++++++++++--
> 1 file changed, 23 insertions(+), 2 deletions(-)
>
> diff --git a/tools/testing/selftests/mincore/mincore_selftest.c b/tools/testing/selftests/mincore/mincore_selftest.c
> index e949a43a6145..e8d7a3a4739f 100644
> --- a/tools/testing/selftests/mincore/mincore_selftest.c
> +++ b/tools/testing/selftests/mincore/mincore_selftest.c
> @@ -12,6 +12,7 @@
> #include <unistd.h>
> #include <stdlib.h>
> #include <sys/mman.h>
> +#include <sys/mount.h>
> #include <string.h>
> #include <fcntl.h>
>
> @@ -283,7 +284,7 @@ TEST(check_file_mmap)
> free(vec);
> }
>
> -
> +#define INPUT_MAX 80
> /*
> * Test mincore() behavior on a page backed by a tmpfs file. This test
> * performs the same steps as the previous one. However, we don't expect
> @@ -291,6 +292,9 @@ TEST(check_file_mmap)
> */
> TEST(check_tmpfs_mmap)
> {
> + char tmpfs_template[] = "/tmp/check_tmpfs_XXXXXX";
> + const char *tmpfs_loc = mkdtemp(tmpfs_template);
> + char testfile[INPUT_MAX];
> unsigned char *vec;
> int vec_size;
> char *addr;
> @@ -300,6 +304,10 @@ TEST(check_tmpfs_mmap)
> int i;
> int ra_pages = 0;
>
> + ASSERT_NE(NULL, tmpfs_loc) {
> + TH_LOG("Can't mkdir tmpfs dentry\n");
> + }
> +
> page_size = sysconf(_SC_PAGESIZE);
> vec_size = FILE_SIZE / page_size;
> if (FILE_SIZE % page_size)
> @@ -311,7 +319,18 @@ TEST(check_tmpfs_mmap)
> }
>
> errno = 0;
> - fd = open("/dev/shm", O_TMPFILE | O_RDWR, 0600);
> + /* Do not use large folios for tmpfs mincore testing */
> + retval = mount("tmpfs", tmpfs_loc, "tmpfs", 0, "huge=never,size=4M");
> + ASSERT_EQ(0, retval) {
> + TH_LOG("Unable to mount tmpfs for testing\n");
> + }
> +
> + retval = snprintf(testfile, INPUT_MAX, "%s/test_file", tmpfs_loc);
> + ASSERT_GE(INPUT_MAX, retval) {
> + TH_LOG("Unable to create a tmpfs for testing\n");
> + }
> +
> + fd = open(testfile, O_CREAT|O_RDWR, 0664);
> ASSERT_NE(-1, fd) {
> TH_LOG("Can't create temporary file: %s",
> strerror(errno));
> @@ -363,6 +382,8 @@ TEST(check_tmpfs_mmap)
> munmap(addr, FILE_SIZE);
> close(fd);
> free(vec);
> + umount(tmpfs_loc);
> + rmdir(tmpfs_loc);
> }
>
> TEST_HARNESS_MAIN
Is there anything that cleans up the mount in case something goes wrong
(we run into an assertion), or will the directory+mount stick around
forever?
But I also wonder whether check_tmpfs_mmap() should be changed to live
with the fact that readahead ("faultaround") could now happen. What's
the reason for not doing that?
--
Cheers,
David / dhildenb
On 2025/4/1 20:54, David Hildenbrand wrote:
> On 26.03.25 04:38, Baolin Wang wrote:
>> When running mincore test cases, I encountered the following failures:
>>
>> "
>> mincore_selftest.c:359:check_tmpfs_mmap:Expected ra_pages (511) == 0 (0)
>> mincore_selftest.c:360:check_tmpfs_mmap:Read-ahead pages found in memory
>> check_tmpfs_mmap: Test terminated by assertion
>> FAIL global.check_tmpfs_mmap
>> not ok 5 global.check_tmpfs_mmap
>> FAILED: 4 / 5 tests passed
>> "
>>
>> The reason for the test case failure is that my system automatically
>> enabled
>> tmpfs large folio allocation by adding the
>> 'transparent_hugepage_tmpfs=always'
>> cmdline. However, the test case still expects the tmpfs mounted on
>> /dev/shm to
>> allocate small folios, which leads to assertion failures when
>> verifying readahead
>> pages.
>>
>> To fix this issue, remount tmpfs to a new test directory and set the
>> 'huge=never'
>> parameter to avoid allocating large folios, which can pass the test.
>>
>> Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
>> ---
>> .../selftests/mincore/mincore_selftest.c | 25 +++++++++++++++++--
>> 1 file changed, 23 insertions(+), 2 deletions(-)
>>
>> diff --git a/tools/testing/selftests/mincore/mincore_selftest.c
>> b/tools/testing/selftests/mincore/mincore_selftest.c
>> index e949a43a6145..e8d7a3a4739f 100644
>> --- a/tools/testing/selftests/mincore/mincore_selftest.c
>> +++ b/tools/testing/selftests/mincore/mincore_selftest.c
>> @@ -12,6 +12,7 @@
>> #include <unistd.h>
>> #include <stdlib.h>
>> #include <sys/mman.h>
>> +#include <sys/mount.h>
>> #include <string.h>
>> #include <fcntl.h>
>> @@ -283,7 +284,7 @@ TEST(check_file_mmap)
>> free(vec);
>> }
>> -
>> +#define INPUT_MAX 80
>> /*
>> * Test mincore() behavior on a page backed by a tmpfs file. This test
>> * performs the same steps as the previous one. However, we don't
>> expect
>> @@ -291,6 +292,9 @@ TEST(check_file_mmap)
>> */
>> TEST(check_tmpfs_mmap)
>> {
>> + char tmpfs_template[] = "/tmp/check_tmpfs_XXXXXX";
>> + const char *tmpfs_loc = mkdtemp(tmpfs_template);
>> + char testfile[INPUT_MAX];
>> unsigned char *vec;
>> int vec_size;
>> char *addr;
>> @@ -300,6 +304,10 @@ TEST(check_tmpfs_mmap)
>> int i;
>> int ra_pages = 0;
>> + ASSERT_NE(NULL, tmpfs_loc) {
>> + TH_LOG("Can't mkdir tmpfs dentry\n");
>> + }
>> +
>> page_size = sysconf(_SC_PAGESIZE);
>> vec_size = FILE_SIZE / page_size;
>> if (FILE_SIZE % page_size)
>> @@ -311,7 +319,18 @@ TEST(check_tmpfs_mmap)
>> }
>> errno = 0;
>> - fd = open("/dev/shm", O_TMPFILE | O_RDWR, 0600);
>> + /* Do not use large folios for tmpfs mincore testing */
>> + retval = mount("tmpfs", tmpfs_loc, "tmpfs", 0,
>> "huge=never,size=4M");
>> + ASSERT_EQ(0, retval) {
>> + TH_LOG("Unable to mount tmpfs for testing\n");
>> + }
>> +
>> + retval = snprintf(testfile, INPUT_MAX, "%s/test_file", tmpfs_loc);
>> + ASSERT_GE(INPUT_MAX, retval) {
>> + TH_LOG("Unable to create a tmpfs for testing\n");
>> + }
>> +
>> + fd = open(testfile, O_CREAT|O_RDWR, 0664);
>> ASSERT_NE(-1, fd) {
>> TH_LOG("Can't create temporary file: %s",
>> strerror(errno));
>> @@ -363,6 +382,8 @@ TEST(check_tmpfs_mmap)
>> munmap(addr, FILE_SIZE);
>> close(fd);
>> free(vec);
>> + umount(tmpfs_loc);
>> + rmdir(tmpfs_loc);
>> }
>> TEST_HARNESS_MAIN
>
> Is there anything that cleans up the mount in case something goes wrong
> (we run into an assertion), or will the directory+mount stick around
> forever?
Good point, will cleanup the mount in the next version.
>
> But I also wonder whether check_tmpfs_mmap() should be changed to live
> with the fact that readahead ("faultaround") could now happen. What's
> the reason for not doing that?
From this test case's description, it doesn't expect any readahead.
"
/*
* Test mincore() behavior on a page backed by a tmpfs file. This test
* performs the same steps as the previous one. However, we don't expect
* any readahead in this case.
*/
"
Maybe adding a new test case to expect the readahead for tmpfs file.
On 07.04.25 05:49, Baolin Wang wrote:
>
>
> On 2025/4/1 20:54, David Hildenbrand wrote:
>> On 26.03.25 04:38, Baolin Wang wrote:
>>> When running mincore test cases, I encountered the following failures:
>>>
>>> "
>>> mincore_selftest.c:359:check_tmpfs_mmap:Expected ra_pages (511) == 0 (0)
>>> mincore_selftest.c:360:check_tmpfs_mmap:Read-ahead pages found in memory
>>> check_tmpfs_mmap: Test terminated by assertion
>>> FAIL global.check_tmpfs_mmap
>>> not ok 5 global.check_tmpfs_mmap
>>> FAILED: 4 / 5 tests passed
>>> "
>>>
>>> The reason for the test case failure is that my system automatically
>>> enabled
>>> tmpfs large folio allocation by adding the
>>> 'transparent_hugepage_tmpfs=always'
>>> cmdline. However, the test case still expects the tmpfs mounted on
>>> /dev/shm to
>>> allocate small folios, which leads to assertion failures when
>>> verifying readahead
>>> pages.
>>>
>>> To fix this issue, remount tmpfs to a new test directory and set the
>>> 'huge=never'
>>> parameter to avoid allocating large folios, which can pass the test.
>>>
>>> Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
>>> ---
>>> .../selftests/mincore/mincore_selftest.c | 25 +++++++++++++++++--
>>> 1 file changed, 23 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/tools/testing/selftests/mincore/mincore_selftest.c
>>> b/tools/testing/selftests/mincore/mincore_selftest.c
>>> index e949a43a6145..e8d7a3a4739f 100644
>>> --- a/tools/testing/selftests/mincore/mincore_selftest.c
>>> +++ b/tools/testing/selftests/mincore/mincore_selftest.c
>>> @@ -12,6 +12,7 @@
>>> #include <unistd.h>
>>> #include <stdlib.h>
>>> #include <sys/mman.h>
>>> +#include <sys/mount.h>
>>> #include <string.h>
>>> #include <fcntl.h>
>>> @@ -283,7 +284,7 @@ TEST(check_file_mmap)
>>> free(vec);
>>> }
>>> -
>>> +#define INPUT_MAX 80
>>> /*
>>> * Test mincore() behavior on a page backed by a tmpfs file. This test
>>> * performs the same steps as the previous one. However, we don't
>>> expect
>>> @@ -291,6 +292,9 @@ TEST(check_file_mmap)
>>> */
>>> TEST(check_tmpfs_mmap)
>>> {
>>> + char tmpfs_template[] = "/tmp/check_tmpfs_XXXXXX";
>>> + const char *tmpfs_loc = mkdtemp(tmpfs_template);
>>> + char testfile[INPUT_MAX];
>>> unsigned char *vec;
>>> int vec_size;
>>> char *addr;
>>> @@ -300,6 +304,10 @@ TEST(check_tmpfs_mmap)
>>> int i;
>>> int ra_pages = 0;
>>> + ASSERT_NE(NULL, tmpfs_loc) {
>>> + TH_LOG("Can't mkdir tmpfs dentry\n");
>>> + }
>>> +
>>> page_size = sysconf(_SC_PAGESIZE);
>>> vec_size = FILE_SIZE / page_size;
>>> if (FILE_SIZE % page_size)
>>> @@ -311,7 +319,18 @@ TEST(check_tmpfs_mmap)
>>> }
>>> errno = 0;
>>> - fd = open("/dev/shm", O_TMPFILE | O_RDWR, 0600);
>>> + /* Do not use large folios for tmpfs mincore testing */
>>> + retval = mount("tmpfs", tmpfs_loc, "tmpfs", 0,
>>> "huge=never,size=4M");
>>> + ASSERT_EQ(0, retval) {
>>> + TH_LOG("Unable to mount tmpfs for testing\n");
>>> + }
>>> +
>>> + retval = snprintf(testfile, INPUT_MAX, "%s/test_file", tmpfs_loc);
>>> + ASSERT_GE(INPUT_MAX, retval) {
>>> + TH_LOG("Unable to create a tmpfs for testing\n");
>>> + }
>>> +
>>> + fd = open(testfile, O_CREAT|O_RDWR, 0664);
>>> ASSERT_NE(-1, fd) {
>>> TH_LOG("Can't create temporary file: %s",
>>> strerror(errno));
>>> @@ -363,6 +382,8 @@ TEST(check_tmpfs_mmap)
>>> munmap(addr, FILE_SIZE);
>>> close(fd);
>>> free(vec);
>>> + umount(tmpfs_loc);
>>> + rmdir(tmpfs_loc);
>>> }
>>> TEST_HARNESS_MAIN
>>
>> Is there anything that cleans up the mount in case something goes wrong
>> (we run into an assertion), or will the directory+mount stick around
>> forever?
>
> Good point, will cleanup the mount in the next version.
>
>>
>> But I also wonder whether check_tmpfs_mmap() should be changed to live
>> with the fact that readahead ("faultaround") could now happen. What's
>> the reason for not doing that?
>
> From this test case's description, it doesn't expect any readahead.
Yes, but why are we testing for that *at all*? We don't make such
assumptions/tests for anon memmory ("no faultaround happened").
Why not simply remove the "We expect only that page to be fetched into
memory." documentation + checking?
--
Cheers,
David / dhildenb
On 2025/4/7 15:49, David Hildenbrand wrote:
> On 07.04.25 05:49, Baolin Wang wrote:
>>
>>
>> On 2025/4/1 20:54, David Hildenbrand wrote:
>>> On 26.03.25 04:38, Baolin Wang wrote:
>>>> When running mincore test cases, I encountered the following failures:
>>>>
>>>> "
>>>> mincore_selftest.c:359:check_tmpfs_mmap:Expected ra_pages (511) == 0
>>>> (0)
>>>> mincore_selftest.c:360:check_tmpfs_mmap:Read-ahead pages found in
>>>> memory
>>>> check_tmpfs_mmap: Test terminated by assertion
>>>> FAIL global.check_tmpfs_mmap
>>>> not ok 5 global.check_tmpfs_mmap
>>>> FAILED: 4 / 5 tests passed
>>>> "
>>>>
>>>> The reason for the test case failure is that my system automatically
>>>> enabled
>>>> tmpfs large folio allocation by adding the
>>>> 'transparent_hugepage_tmpfs=always'
>>>> cmdline. However, the test case still expects the tmpfs mounted on
>>>> /dev/shm to
>>>> allocate small folios, which leads to assertion failures when
>>>> verifying readahead
>>>> pages.
>>>>
>>>> To fix this issue, remount tmpfs to a new test directory and set the
>>>> 'huge=never'
>>>> parameter to avoid allocating large folios, which can pass the test.
>>>>
>>>> Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
>>>> ---
>>>> .../selftests/mincore/mincore_selftest.c | 25
>>>> +++++++++++++++++--
>>>> 1 file changed, 23 insertions(+), 2 deletions(-)
>>>>
>>>> diff --git a/tools/testing/selftests/mincore/mincore_selftest.c
>>>> b/tools/testing/selftests/mincore/mincore_selftest.c
>>>> index e949a43a6145..e8d7a3a4739f 100644
>>>> --- a/tools/testing/selftests/mincore/mincore_selftest.c
>>>> +++ b/tools/testing/selftests/mincore/mincore_selftest.c
>>>> @@ -12,6 +12,7 @@
>>>> #include <unistd.h>
>>>> #include <stdlib.h>
>>>> #include <sys/mman.h>
>>>> +#include <sys/mount.h>
>>>> #include <string.h>
>>>> #include <fcntl.h>
>>>> @@ -283,7 +284,7 @@ TEST(check_file_mmap)
>>>> free(vec);
>>>> }
>>>> -
>>>> +#define INPUT_MAX 80
>>>> /*
>>>> * Test mincore() behavior on a page backed by a tmpfs file.
>>>> This test
>>>> * performs the same steps as the previous one. However, we don't
>>>> expect
>>>> @@ -291,6 +292,9 @@ TEST(check_file_mmap)
>>>> */
>>>> TEST(check_tmpfs_mmap)
>>>> {
>>>> + char tmpfs_template[] = "/tmp/check_tmpfs_XXXXXX";
>>>> + const char *tmpfs_loc = mkdtemp(tmpfs_template);
>>>> + char testfile[INPUT_MAX];
>>>> unsigned char *vec;
>>>> int vec_size;
>>>> char *addr;
>>>> @@ -300,6 +304,10 @@ TEST(check_tmpfs_mmap)
>>>> int i;
>>>> int ra_pages = 0;
>>>> + ASSERT_NE(NULL, tmpfs_loc) {
>>>> + TH_LOG("Can't mkdir tmpfs dentry\n");
>>>> + }
>>>> +
>>>> page_size = sysconf(_SC_PAGESIZE);
>>>> vec_size = FILE_SIZE / page_size;
>>>> if (FILE_SIZE % page_size)
>>>> @@ -311,7 +319,18 @@ TEST(check_tmpfs_mmap)
>>>> }
>>>> errno = 0;
>>>> - fd = open("/dev/shm", O_TMPFILE | O_RDWR, 0600);
>>>> + /* Do not use large folios for tmpfs mincore testing */
>>>> + retval = mount("tmpfs", tmpfs_loc, "tmpfs", 0,
>>>> "huge=never,size=4M");
>>>> + ASSERT_EQ(0, retval) {
>>>> + TH_LOG("Unable to mount tmpfs for testing\n");
>>>> + }
>>>> +
>>>> + retval = snprintf(testfile, INPUT_MAX, "%s/test_file", tmpfs_loc);
>>>> + ASSERT_GE(INPUT_MAX, retval) {
>>>> + TH_LOG("Unable to create a tmpfs for testing\n");
>>>> + }
>>>> +
>>>> + fd = open(testfile, O_CREAT|O_RDWR, 0664);
>>>> ASSERT_NE(-1, fd) {
>>>> TH_LOG("Can't create temporary file: %s",
>>>> strerror(errno));
>>>> @@ -363,6 +382,8 @@ TEST(check_tmpfs_mmap)
>>>> munmap(addr, FILE_SIZE);
>>>> close(fd);
>>>> free(vec);
>>>> + umount(tmpfs_loc);
>>>> + rmdir(tmpfs_loc);
>>>> }
>>>> TEST_HARNESS_MAIN
>>>
>>> Is there anything that cleans up the mount in case something goes wrong
>>> (we run into an assertion), or will the directory+mount stick around
>>> forever?
>>
>> Good point, will cleanup the mount in the next version.
>>
>>>
>>> But I also wonder whether check_tmpfs_mmap() should be changed to live
>>> with the fact that readahead ("faultaround") could now happen. What's
>>> the reason for not doing that?
>>
>> From this test case's description, it doesn't expect any readahead.
>
> Yes, but why are we testing for that *at all*? We don't make such
> assumptions/tests for anon memmory ("no faultaround happened").
>
> Why not simply remove the "We expect only that page to be fetched into
> memory." documentation + checking?
OK. I'm fine with dropping the readahead check. Thanks.
On 25 Mar 2025, at 23:38, Baolin Wang wrote:
> When running mincore test cases, I encountered the following failures:
>
> "
> mincore_selftest.c:359:check_tmpfs_mmap:Expected ra_pages (511) == 0 (0)
> mincore_selftest.c:360:check_tmpfs_mmap:Read-ahead pages found in memory
> check_tmpfs_mmap: Test terminated by assertion
> FAIL global.check_tmpfs_mmap
> not ok 5 global.check_tmpfs_mmap
> FAILED: 4 / 5 tests passed
> "
>
> The reason for the test case failure is that my system automatically enabled
> tmpfs large folio allocation by adding the 'transparent_hugepage_tmpfs=always'
> cmdline. However, the test case still expects the tmpfs mounted on /dev/shm to
> allocate small folios, which leads to assertion failures when verifying readahead
> pages.
>
> To fix this issue, remount tmpfs to a new test directory and set the 'huge=never'
> parameter to avoid allocating large folios, which can pass the test.
>
> Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
> ---
> .../selftests/mincore/mincore_selftest.c | 25 +++++++++++++++++--
> 1 file changed, 23 insertions(+), 2 deletions(-)
>
<snip>
>
> errno = 0;
> - fd = open("/dev/shm", O_TMPFILE | O_RDWR, 0600);
> + /* Do not use large folios for tmpfs mincore testing */
> + retval = mount("tmpfs", tmpfs_loc, "tmpfs", 0, "huge=never,size=4M");
> + ASSERT_EQ(0, retval) {
> + TH_LOG("Unable to mount tmpfs for testing\n");
> + }
> +
> + retval = snprintf(testfile, INPUT_MAX, "%s/test_file", tmpfs_loc);
> + ASSERT_GE(INPUT_MAX, retval) {
> + TH_LOG("Unable to create a tmpfs for testing\n");
> + }
> +
> + fd = open(testfile, O_CREAT|O_RDWR, 0664);
The fd permission is changed from 0600 to 0664, but it probably does not
matter.
> ASSERT_NE(-1, fd) {
> TH_LOG("Can't create temporary file: %s",
> strerror(errno));
> @@ -363,6 +382,8 @@ TEST(check_tmpfs_mmap)
> munmap(addr, FILE_SIZE);
> close(fd);
> free(vec);
> + umount(tmpfs_loc);
> + rmdir(tmpfs_loc);
> }
>
> TEST_HARNESS_MAIN
> --
> 2.43.5
Otherwise, LGTM. Reviewed-by: Zi Yan <ziy@nvidia.com>
--
Best Regards,
Yan, Zi
On 2025/3/27 22:36, Zi Yan wrote:
> On 25 Mar 2025, at 23:38, Baolin Wang wrote:
>
>> When running mincore test cases, I encountered the following failures:
>>
>> "
>> mincore_selftest.c:359:check_tmpfs_mmap:Expected ra_pages (511) == 0 (0)
>> mincore_selftest.c:360:check_tmpfs_mmap:Read-ahead pages found in memory
>> check_tmpfs_mmap: Test terminated by assertion
>> FAIL global.check_tmpfs_mmap
>> not ok 5 global.check_tmpfs_mmap
>> FAILED: 4 / 5 tests passed
>> "
>>
>> The reason for the test case failure is that my system automatically enabled
>> tmpfs large folio allocation by adding the 'transparent_hugepage_tmpfs=always'
>> cmdline. However, the test case still expects the tmpfs mounted on /dev/shm to
>> allocate small folios, which leads to assertion failures when verifying readahead
>> pages.
>>
>> To fix this issue, remount tmpfs to a new test directory and set the 'huge=never'
>> parameter to avoid allocating large folios, which can pass the test.
>>
>> Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
>> ---
>> .../selftests/mincore/mincore_selftest.c | 25 +++++++++++++++++--
>> 1 file changed, 23 insertions(+), 2 deletions(-)
>>
>
> <snip>
>
>>
>> errno = 0;
>> - fd = open("/dev/shm", O_TMPFILE | O_RDWR, 0600);
>> + /* Do not use large folios for tmpfs mincore testing */
>> + retval = mount("tmpfs", tmpfs_loc, "tmpfs", 0, "huge=never,size=4M");
>> + ASSERT_EQ(0, retval) {
>> + TH_LOG("Unable to mount tmpfs for testing\n");
>> + }
>> +
>> + retval = snprintf(testfile, INPUT_MAX, "%s/test_file", tmpfs_loc);
>> + ASSERT_GE(INPUT_MAX, retval) {
>> + TH_LOG("Unable to create a tmpfs for testing\n");
>> + }
>> +
>> + fd = open(testfile, O_CREAT|O_RDWR, 0664);
>
> The fd permission is changed from 0600 to 0664, but it probably does not
> matter.
It is just a temp file, so it doesn't matter.
>
>> ASSERT_NE(-1, fd) {
>> TH_LOG("Can't create temporary file: %s",
>> strerror(errno));
>> @@ -363,6 +382,8 @@ TEST(check_tmpfs_mmap)
>> munmap(addr, FILE_SIZE);
>> close(fd);
>> free(vec);
>> + umount(tmpfs_loc);
>> + rmdir(tmpfs_loc);
>> }
>>
>> TEST_HARNESS_MAIN
>> --
>> 2.43.5
>
> Otherwise, LGTM. Reviewed-by: Zi Yan <ziy@nvidia.com>
Thanks for reviewing.
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