[LTP] [PATCH v4] syscalls/sync_file_range: add partial file sync test-cases

[Caspar Zhang]

Hi Sumit,

On Mon, Jun 10, 2019 at 03:43:16PM +0530, Sumit Garg wrote:

<snip>

>
> -	if (written >= FILE_SIZE)
> +	if ((written >= tc->exp_sync_size) &&
> +	    (written <= (tc->exp_sync_size + tc->exp_sync_size/10)))

May I ask why it is +1/10 of expected sync_size as upper bound here,
since it looks like a magic number to me.

We encountered test failure in the second case in a debug kernel,
reproducible about once out of 20 times run.

The reason is unclear yet, however my guess is that more pages could be
written to disk in a debug kernel than a release kernel.

My codes and config as below:

tree: https://github.com/alibaba/cloud-kernel :: ck-4.19.67 branch;
config: https://github.com/alibaba/cloud-kernel/blob/master/config-4.19.y-x86_64-debug

If you like you can build a test kernel on a KVM guest and try to
reproduce, or just run a RHEL8 kernel I guess (@Li Wang, you can have a
try on RHEL8 debug kernel if possible).

a sample output:

tst_device.c:87: INFO: Found free device 0 '/dev/loop0'
tst_supported_fs_types.c:60: INFO: Kernel supports ext2
tst_supported_fs_types.c:44: INFO: mkfs.ext2 does exist
tst_supported_fs_types.c:60: INFO: Kernel supports ext3
tst_supported_fs_types.c:44: INFO: mkfs.ext3 does exist
tst_supported_fs_types.c:60: INFO: Kernel supports ext4
tst_supported_fs_types.c:44: INFO: mkfs.ext4 does exist
tst_supported_fs_types.c:60: INFO: Kernel supports xfs
tst_supported_fs_types.c:44: INFO: mkfs.xfs does exist
tst_supported_fs_types.c:60: INFO: Kernel supports btrfs
tst_supported_fs_types.c:44: INFO: mkfs.btrfs does exist
tst_supported_fs_types.c:60: INFO: Kernel supports vfat
tst_supported_fs_types.c:44: INFO: mkfs.vfat does exist
tst_supported_fs_types.c:83: INFO: Filesystem exfat is not supported
tst_supported_fs_types.c:83: INFO: Filesystem ntfs is not supported
tst_test.c:1179: INFO: Testing on ext2
tst_mkfs.c:90: INFO: Formatting /dev/loop0 with ext2 opts='' extra opts=''
mke2fs 1.43.5 (04-Aug-2017)
tst_test.c:1118: INFO: Timeout per run is 0h 05m 00s
sync_file_range02.c:71: PASS: Sync equals write
sync_file_range02.c:71: PASS: Sync inside of write
sync_file_range02.c:71: PASS: Sync overlaps with write
tst_test.c:1179: INFO: Testing on ext3
tst_mkfs.c:90: INFO: Formatting /dev/loop0 with ext3 opts='' extra opts=''
mke2fs 1.43.5 (04-Aug-2017)
tst_test.c:1118: INFO: Timeout per run is 0h 05m 00s
sync_file_range02.c:71: PASS: Sync equals write
sync_file_range02.c:71: PASS: Sync inside of write
sync_file_range02.c:71: PASS: Sync overlaps with write
tst_test.c:1179: INFO: Testing on ext4
tst_mkfs.c:90: INFO: Formatting /dev/loop0 with ext4 opts='' extra opts=''
mke2fs 1.43.5 (04-Aug-2017)
tst_test.c:1118: INFO: Timeout per run is 0h 05m 00s
sync_file_range02.c:71: PASS: Sync equals write
sync_file_range02.c:74: FAIL: Sync inside of write: Synced 19658752, expected 16777216
                        ^^^^
sync_file_range02.c:71: PASS: Sync overlaps with write
tst_test.c:1179: INFO: Testing on xfs
tst_mkfs.c:90: INFO: Formatting /dev/loop0 with xfs opts='' extra opts=''
tst_test.c:1118: INFO: Timeout per run is 0h 05m 00s
sync_file_range02.c:71: PASS: Sync equals write
sync_file_range02.c:71: PASS: Sync inside of write
sync_file_range02.c:71: PASS: Sync overlaps with write
tst_test.c:1179: INFO: Testing on btrfs
tst_mkfs.c:90: INFO: Formatting /dev/loop0 with btrfs opts='' extra opts=''
tst_test.c:1118: INFO: Timeout per run is 0h 05m 00s
sync_file_range02.c:71: PASS: Sync equals write
sync_file_range02.c:71: PASS: Sync inside of write
sync_file_range02.c:71: PASS: Sync overlaps with write
tst_test.c:1179: INFO: Testing on vfat
tst_mkfs.c:90: INFO: Formatting /dev/loop0 with vfat opts='' extra opts=''
tst_test.c:1118: INFO: Timeout per run is 0h 05m 00s
sync_file_range02.c:111: INFO: Pre-filling file
sync_file_range02.c:71: PASS: Sync equals write
sync_file_range02.c:71: PASS: Sync inside of write
sync_file_range02.c:71: PASS: Sync overlaps with write

Summary:
passed   17
failed   1
skipped  0
warnings 0

Any thoughts would be appreicated.

Thanks,
Caspar


>  		tst_res(TPASS, "Test file range synced to device");
>  	else
> -		tst_res(TFAIL, "Synced %li, expected %i", written, FILE_SIZE);
> +		tst_res(TFAIL, "Synced %li, expected %li", written,
> +			tc->exp_sync_size);
> +}
> +
> +static struct testcase testcases[] = {
> +	{ FNAME1, 0, FILE_SZ, FILE_SZ, 0, FILE_SZ_MB },
> +	{ FNAME2, FILE_SZ/4, FILE_SZ/2, FILE_SZ/2, 0, FILE_SZ_MB },
> +	{ FNAME3, FILE_SZ/4, FILE_SZ/2, FILE_SZ/4, FILE_SZ/2, FILE_SZ_MB/4 },
> +};
> +
> +static void run(unsigned int i)
> +{
> +	verify_sync_file_range(&testcases[i]);
>  }
>
>  static void setup(void)
>  {
>  	if (!check_sync_file_range())
>  		tst_brk(TCONF, "sync_file_range() not supported");
> +
> +	if (!strcmp(tst_device->fs_type, "vfat")) {
> +		tst_res(TINFO, "Pre-filling file");
> +		tst_fill_file(FNAME3, 0, TST_MB, FILE_SZ_MB);
> +		sync();
> +	}
>  }
>
>  static struct tst_test test = {
> +	.tcnt = ARRAY_SIZE(testcases),
>  	.needs_root = 1,
>  	.mount_device = 1,
>  	.all_filesystems = 1,
>  	.mntpoint = MNTPOINT,
>  	.setup = setup,
> -	.test_all = verify_sync_file_range,
> +	.test = run,
>  };
> --
> 2.7.4
>
>
> --
> Mailing list info: https://lists.linux.it/listinfo/ltp

--
        Thanks,
        Caspar