[LTP] [PATCH 2/2] df01.sh: Use tst_fsfreeze for XFS on kernel >= 5.19

[Eric Sandeen]

On 3/13/23 9:38 AM, Cyril Hrubis wrote:
> Hi!
>> XFS since kernel 5.19 postpone certain operation.  Use LTP fsfreeze
>> implementation to force all the background garbage collection to run
>> to completion.
>>
>> Link: https://lore.kernel.org/linux-block/974cc110-d47e-5fae-af5f-e2e610720e2d@redhat.com/
>> Suggested-by: Eric Sandeen <sandeen@redhat.com>
>> Signed-off-by: Petr Vorel <pvorel@suse.cz>
>> ---
>>  testcases/commands/df/df01.sh | 7 ++++++-
>>  1 file changed, 6 insertions(+), 1 deletion(-)
>>
>> diff --git a/testcases/commands/df/df01.sh b/testcases/commands/df/df01.sh
>> index ae0449c3c..699d1538f 100755
>> --- a/testcases/commands/df/df01.sh
>> +++ b/testcases/commands/df/df01.sh
>> @@ -1,7 +1,7 @@
>>  #!/bin/sh
>>  # SPDX-License-Identifier: GPL-2.0-or-later
>>  # Copyright (c) 2015 Fujitsu Ltd.
>> -# Copyright (c) 2018-2022 Petr Vorel <pvorel@suse.cz>
>> +# Copyright (c) 2018-2023 Petr Vorel <pvorel@suse.cz>
>>  # Author: Zhang Jin <jy_zhangjin@cn.fujitsu.com>
>>  #
>>  # Test df command with some basic options.
>> @@ -46,6 +46,11 @@ df_test()
>>  
>>  	ROD_SILENT rm -rf $TST_MNTPOINT/testimg
>>  
>> +	# force all the background garbage collection to run to completion
>> +	if [ "$TST_FS_TYPE" = "xfs" ] && tst_kvcmp -ge "5.19"; then
>> +		tst_fsfreeze $TST_MNTPOINT
>> +	fi
> 
> This looks overly specific, can't we just freeze and unfreeze the FS
> without looking at kernel version? Or will we get errors on older XFS?
> 
> I suppose that this may still start to fail on distribution kernels if
> some of the newer functionality gets backported...

Yup, I agree. Freeze should be safe for any kernel, I wouldn't condition it either.

(You do want to be very sure that you're not freezing the root fs, tho,
if that is any possibility.)

-Eric

> Otherwise it looks good.
>