[PATCH v3 10/13] ext4/061: Atomic writes stress test for bigalloc using fio crc verifier

Ojaswin Mujoo
2025-07-12T14:14:04Z

From: "Ritesh Harjani (IBM)" <ritesh.list@gmail.com>

We brute force all possible blocksize & clustersize combinations on
a bigalloc filesystem for stressing atomic write using fio data crc
verifier. We run nproc * $LOAD_FACTOR threads in parallel writing to
a single $SCRATCH_MNT/test-file. With atomic writes this test ensures
that we never see the mix of data contents from different threads on
a given bsrange.

Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Signed-off-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
---
tests/ext4/061 | 130 +++++++++++++++++++++++++++++++++++++++++++++
tests/ext4/061.out | 2 +
2 files changed, 132 insertions(+)
create mode 100755 tests/ext4/061
create mode 100644 tests/ext4/061.out

diff --git a/tests/ext4/061 b/tests/ext4/061
new file mode 100755
index 00000000..a0e49249
--- /dev/null
+++ b/tests/ext4/061
@@ -0,0 +1,130 @@
+#! /bin/bash
+# SPDX-License-Identifier: GPL-2.0
+# Copyright (c) 2025 IBM Corporation. All Rights Reserved.
+#
+# FS QA Test 061
+#
+# Brute force all possible blocksize clustersize combination on a bigalloc
+# filesystem for stressing atomic write using fio data crc verifier. We run
+# nproc * 2 * $LOAD_FACTOR threads in parallel writing to a single
+# $SCRATCH_MNT/test-file. With fio aio-dio atomic write this test ensures that
+# we should never see the mix of data contents from different threads for any
+# given fio blocksize.
+#
+
+. ./common/preamble
+. ./common/atomicwrites
+
+_begin_fstest auto rw stress atomicwrites
+
+_require_scratch_write_atomic
+_require_aiodio
+
+FIO_LOAD=$(($(nproc) * 2 * LOAD_FACTOR))
+SIZE=$((100*1024*1024))
+fiobsize=4096
+
+# Calculate fsblocksize as per bdev atomic write units.
+bdev_awu_min=$(_get_atomic_write_unit_min $SCRATCH_DEV)
+bdev_awu_max=$(_get_atomic_write_unit_max $SCRATCH_DEV)
+fsblocksize=$(_max 4096 "$bdev_awu_min")
+
+function create_fio_configs()
+{
+ create_fio_aw_config
+ create_fio_verify_config
+}
+
+function create_fio_verify_config()
+{
+cat >$fio_verify_config <<EOF
+ [aio-dio-aw-verify]
+ direct=1
+ ioengine=libaio
+ rw=randwrite
+ bs=$fiobsize
+ fallocate=native
+ filename=$SCRATCH_MNT/test-file
+ size=$SIZE
+ iodepth=$FIO_LOAD
+ numjobs=$FIO_LOAD
+ atomic=1
+ group_reporting=1
+
+ verify_only=1
+ verify_state_save=0
+ verify=crc32c
+ verify_fatal=1
+ verify_write_sequence=0
+EOF
+}
+
+function create_fio_aw_config()
+{
+cat >$fio_aw_config <<EOF
+ [aio-dio-aw]
+ direct=1
+ ioengine=libaio
+ rw=randwrite
+ bs=$fiobsize
+ fallocate=native
+ filename=$SCRATCH_MNT/test-file
+ size=$SIZE
+ iodepth=$FIO_LOAD
+ numjobs=$FIO_LOAD
+ group_reporting=1
+ atomic=1
+
+ verify_state_save=0
+ verify=crc32c
+ do_verify=0
+
+EOF
+}
+
+# Let's create a sample fio config to check whether fio supports all options.
+fio_aw_config=$tmp.aw.fio
+fio_verify_config=$tmp.verify.fio
+fio_out=$tmp.fio.out
+
+create_fio_configs
+_require_fio $fio_aw_config
+
+for ((fsblocksize=$fsblocksize; fsblocksize <= $(_get_page_size); fsblocksize = $fsblocksize << 1)); do
+ # cluster sizes above 16 x blocksize are experimental so avoid them
+ # Also, cap cluster size at 128kb to keep it reasonable for large
+ # blocks size
+ fs_max_clustersize=$(_min $((16 * fsblocksize)) "$bdev_awu_max" $((128 * 1024)))
+
+ for ((fsclustersize=$fsblocksize; fsclustersize <= $fs_max_clustersize; fsclustersize = $fsclustersize << 1)); do
+ for ((fiobsize = $fsblocksize; fiobsize <= $fsclustersize; fiobsize = $fiobsize << 1)); do
+ MKFS_OPTIONS="-O bigalloc -b $fsblocksize -C $fsclustersize"
+ _scratch_mkfs_ext4 >> $seqres.full 2>&1 || continue
+ if _try_scratch_mount >> $seqres.full 2>&1; then
+ echo "== FIO test for fsblocksize=$fsblocksize fsclustersize=$fsclustersize fiobsize=$fiobsize ==" >> $seqres.full
+
+ touch $SCRATCH_MNT/f1
+ create_fio_configs
+
+ cat $fio_aw_config >> $seqres.full
+ echo >> $seqres.full
+ cat $fio_verify_config >> $seqres.full
+
+ $FIO_PROG $fio_aw_config >> $seqres.full
+ ret1=$?
+
+ $FIO_PROG $fio_verify_config >> $seqres.full
+ ret2=$?
+
+ _scratch_unmount
+
+ [[ $ret1 -eq 0 && $ret2 -eq 0 ]] || _fail "fio with atomic write failed"
+ fi
+ done
+ done
+done
+
+# success, all done
+echo Silence is golden
+status=0
+exit
diff --git a/tests/ext4/061.out b/tests/ext4/061.out
new file mode 100644
index 00000000..273be9e0
--- /dev/null
+++ b/tests/ext4/061.out
@@ -0,0 +1,2 @@
+QA output created by 061
+Silence is golden
--
2.49.0