Re: [PATCHv3 4/4] generic/679: Add a test to check unwritten extents tracking

[Dave Chinner <david@fromorbit.com>]

On Thu, Mar 31, 2022 at 06:24:23PM +0530, Ritesh Harjani wrote:
> From: Ritesh Harjani <riteshh@linux.ibm.com>
> 
> With these sequence of operation (in certain cases like with ext4 fast_commit)
> could miss to track unwritten extents during replay phase
> (after sudden FS shutdown).
> 
> This fstest adds a test case to test this.
> 
> 5e4d0eba1ccaf19f
> ext4: fix fast commit may miss tracking range for FALLOC_FL_ZERO_RANGE
> 
> Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com>
> ---
>  tests/generic/679     | 65 +++++++++++++++++++++++++++++++++++++++++++
>  tests/generic/679.out |  6 ++++
>  2 files changed, 71 insertions(+)
>  create mode 100755 tests/generic/679
>  create mode 100644 tests/generic/679.out
> 
> diff --git a/tests/generic/679 b/tests/generic/679
> new file mode 100755
> index 00000000..4f35a9cd
> --- /dev/null
> +++ b/tests/generic/679
> @@ -0,0 +1,65 @@
> +#! /bin/bash
> +# SPDX-License-Identifier: GPL-2.0
> +# Copyright (c) 2022 IBM Corporation.  All Rights Reserved.
> +#
> +# FS QA Test 679
> +#
> +# Test below sequence of operation which (w/o below kernel patch) in case of
> +# ext4 with fast_commit may misss to track unwritten extents.
> +# commit 5e4d0eba1ccaf19f
> +# ext4: fix fast commit may miss tracking range for FALLOC_FL_ZERO_RANGE
> +#
> +. ./common/preamble
> +_begin_fstest auto quick log shutdown recoveryloop
> +
> +# Override the default cleanup function.
> +_cleanup()
> +{
> +	cd /
> +	rm -r -f $tmp.*
> +}

Same as default.

> +
> +# Import common functions.
> +. ./common/filter
> +. ./common/punch
> +
> +# real QA test starts here
> +
> +# Modify as appropriate.
> +_supported_fs generic
> +_require_scratch
> +_require_xfs_io_command "fzero"
> +_require_xfs_io_command "fiemap"
> +_require_scratch_shutdown
> +
> +t1=$SCRATCH_MNT/t1
> +
> +_scratch_mkfs > $seqres.full 2>&1
> +
> +_scratch_mount >> $seqres.full 2>&1
> +
> +bs=$(_get_file_block_size $SCRATCH_MNT)
> +
> +# create and write data to t1
> +$XFS_IO_PROG -f -c "pwrite 0 $((100*$bs))" $t1 | _filter_xfs_io_numbers
> +
> +# fsync t1
> +$XFS_IO_PROG -c "fsync" $t1
> +
> +# fzero certain range in between
> +$XFS_IO_PROG -c "fzero -k  $((40*$bs)) $((20*$bs))" $t1
> +
> +# fsync t1
> +$XFS_IO_PROG -c "fsync" $t1
> +
> +# shutdown FS now for replay of journal to kick during next mount
> +_scratch_shutdown -v >> $seqres.full 2>&1
> +
> +_scratch_cycle_mount
> +
> +# check fiemap reported is valid or not
> +$XFS_IO_PROG -c "fiemap -v" $t1 | _filter_fiemap_flags $bs
> +
> +# success, all done
> +status=0
> +exit
> diff --git a/tests/generic/679.out b/tests/generic/679.out
> new file mode 100644
> index 00000000..4d3c3377
> --- /dev/null
> +++ b/tests/generic/679.out
> @@ -0,0 +1,6 @@
> +QA output created by 679
> +wrote XXXX/XXXX bytes at offset XXXX
> +XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
> +0: [0..39]: none
> +1: [40..59]: unwritten
> +2: [60..99]: nonelast

This is a subset of the the previous test, and looks like it should
be tested first before adding the second file and punch operation
the previous test adds to this write/zero operations. IOWs, they
look like they could easily be combined into a single test without
losing anything except having an extra test that has to be run...

Cheers,

Dave.
-- 
Dave Chinner
david@fromorbit.com