This test is based on generic/033, which originally used zero range operations to reproduce indlen reservation problems. Zero range now includes a pagecache flush before it updates extents, which means generic/033 is no longer able to reproduce the problem it was originally written to test. Create a new test that uses an XFS-specific mechanism (in DEBUG mode) to induce delalloc extent splits and reproduce the problem originally reproduced by generic/033. In addition, update the test to include a larger buffered write pattern that is known to reproduce premature indlen exhaustion on delalloc extents. Signed-off-by: Brian Foster <bfoster@xxxxxxxxxx> --- v2: - Copy original generic/033 rather than move. - Squash series into single patch. v1: http://www.spinics.net/lists/fstests/msg05187.html tests/xfs/289 | 109 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ tests/xfs/289.out | 2 + tests/xfs/group | 1 + 3 files changed, 112 insertions(+) create mode 100755 tests/xfs/289 create mode 100644 tests/xfs/289.out diff --git a/tests/xfs/289 b/tests/xfs/289 new file mode 100755 index 0000000..11844cf --- /dev/null +++ b/tests/xfs/289 @@ -0,0 +1,109 @@ +#! /bin/bash +# FS QA Test No. 289 +# +# This test stresses indirect block reservation for delayed allocation extents. +# XFS reserves extra blocks for deferred allocation of delalloc extents. These +# reserved blocks can be divided among more extents than anticipated if the +# original extent for which the blocks were reserved is split into multiple +# delalloc extents. If this scenario repeats, eventually some extents are left +# without any indirect block reservation whatsoever. This leads to assert +# failures and possibly other problems in XFS. +# +#----------------------------------------------------------------------- +# Copyright (c) 2017 Red Hat, Inc. All Rights Reserved. +# +# This program is free software; you can redistribute it and/or +# modify it under the terms of the GNU General Public License as +# published by the Free Software Foundation. +# +# This program is distributed in the hope that it would be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with this program; if not, write the Free Software Foundation, +# Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA +#----------------------------------------------------------------------- +# + +seq=`basename $0` +seqres=$RESULT_DIR/$seq +echo "QA output created by $seq" + +here=`pwd` +tmp=/tmp/$$ +status=1 # failure is the default! +trap "_cleanup; exit \$status" 0 1 2 3 15 + +_cleanup() +{ + cd / + rm -f $tmp.* +} + +# get standard environment, filters and checks +. ./common/rc +. ./common/punch + +# real QA test starts here +rm -f $seqres.full + +# Modify as appropriate. +_supported_fs generic +_supported_os Linux +_require_scratch +_require_xfs_sysfs $(_short_dev $TEST_DEV)/drop_writes + +_scratch_mkfs >/dev/null 2>&1 +_scratch_mount + +sdev=$(_short_dev $SCRATCH_DEV) +file=$SCRATCH_MNT/file.$seq +bytes=$((64 * 1024)) + +# create sequential delayed allocation +$XFS_IO_PROG -f -c "pwrite 0 $bytes" $file >> $seqres.full 2>&1 + +# Enable write drops. All buffered writes are dropped from this point on. +echo 1 > /sys/fs/xfs/$sdev/drop_writes + +# Write every other 4k range to split the larger delalloc extent into many more +# smaller extents. Use pwrite because with write failures enabled, all +# preexisting delalloc blocks in the range of the I/O are tossed without +# discretion. This allows manipulation of the delalloc extent without conversion +# to real blocks (and thus releasing the indirect reservation). +endoff=$((bytes - 4096)) +for i in $(seq 0 8192 $endoff); do + $XFS_IO_PROG -c "pwrite $i 4k" $file >> $seqres.full 2>&1 +done + +# now pwrite the opposite set to remove remaining delalloc extents +for i in $(seq 4096 8192 $endoff); do + $XFS_IO_PROG -c "pwrite $i 4k" $file >> $seqres.full 2>&1 +done + +echo 0 > /sys/fs/xfs/$sdev/drop_writes + +_scratch_cycle_mount +$XFS_IO_PROG -c 'bmap -vp' $file | _filter_bmap + +# Now test a buffered write workload with larger extents. Write a 100m extent, +# split it at the 3/4 mark, then write another 100m extent that is contiguous +# with the 1/4 portion of the split extent. Repeat several times. This pattern +# is known to prematurely exhaust indirect reservations and cause warnings and +# assert failures. +rm -f $file +for offset in $(seq 0 100 500); do + $XFS_IO_PROG -fc "pwrite ${offset}m 100m" $file >> $seqres.full 2>&1 + + punchoffset=$((offset + 75)) + echo 1 > /sys/fs/xfs/$sdev/drop_writes + $XFS_IO_PROG -c "pwrite ${punchoffset}m 4k" $file >> $seqres.full 2>&1 + echo 0 > /sys/fs/xfs/$sdev/drop_writes +done + +echo "Silence is golden." + +status=0 +exit diff --git a/tests/xfs/289.out b/tests/xfs/289.out new file mode 100644 index 0000000..72e60f9 --- /dev/null +++ b/tests/xfs/289.out @@ -0,0 +1,2 @@ +QA output created by 289 +Silence is golden. diff --git a/tests/xfs/group b/tests/xfs/group index e2dfae2..7c188fe 100644 --- a/tests/xfs/group +++ b/tests/xfs/group @@ -280,6 +280,7 @@ 283 dump ioctl auto quick 284 auto quick dump copy db mkfs repair 287 auto dump quota quick +289 auto quick rw 290 auto rw prealloc quick ioctl zero 291 auto repair 292 auto mkfs quick -- 2.7.4 -- To unsubscribe from this list: send the line "unsubscribe linux-xfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
