generic: Test races between mmap and normal write for prefaulted ranges

Add test which spawns two threads both writing one file via mmap which
has been previously prefaulted by reading. Do the same test when one
thread accesses the file via mmap and the other one via normal write.
This is mainly interesting to uncover races in DAX fault handling and
between DAX fault handling and write path.

Signed-off-by: Jan Kara <jack@suse.cz>
Acked-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
This commit is contained in:
Jan Kara
2016-05-09 10:54:25 +10:00
committed by Dave Chinner
parent 96a3ad1630
commit 9e8b4e2755
4 changed files with 151 additions and 2 deletions
+17 -2
View File
@@ -67,6 +67,7 @@
long page_size;
long page_offs[THREADS];
int use_wr[THREADS];
int prefault = 0;
void *pt_page_marker(void *args)
{
@@ -122,6 +123,16 @@ int test_this(int fd, loff_t sz)
exit(20);
}
if (prefault) {
for (i = 0; i < npages; i++) {
if (vastart[i * page_size] != 0) {
fprintf(stderr, "Prefaulting found non-zero "
"value in page %d: %d\n", i,
vastart[i * page_size]);
}
}
}
/* prepare the thread args */
for (i = 0; i < THREADS; i++) {
targs[i][0] = (void *)(long)fd;
@@ -185,7 +196,7 @@ int main(int argc, char **argv)
for (i = 1; i < THREADS; i++)
page_offs[i] = page_offs[i-1] + step;
while ((opt = getopt(argc, argv, "fw")) > 0) {
while ((opt = getopt(argc, argv, "fwr")) > 0) {
switch (opt) {
case 'f':
/* ignore errors */
@@ -195,6 +206,10 @@ int main(int argc, char **argv)
/* use writes instead of mmap for one thread */
use_wr[0] = 1;
break;
case 'r':
/* prefault mmapped area by reading it */
prefault = 1;
break;
default:
fprintf(stderr, "ERROR: Unknown option character.\n");
exit(1);
@@ -202,7 +217,7 @@ int main(int argc, char **argv)
}
if (optind != argc - 2) {
fprintf(stderr, "ERROR: usage: holetest [-fw] "
fprintf(stderr, "ERROR: usage: holetest [-fwr] "
"FILENAME FILESIZEinMB\n");
exit(1);
}
+60
View File
@@ -0,0 +1,60 @@
#! /bin/bash
# FSQA Test No. 344
#
# Test races between mmap from racing threads when pages are prefaulted,
# Test races between mmap and buffered writes when pages are prefaulted.
#
#-----------------------------------------------------------------------
#
# Copyright (C) 2016 SUSE Linux Products GmbH. All Rights Reserved.
# Author: Jan Kara <jack@suse.cz>
#
# 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"
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 and checks
. ./common/rc
# real QA test starts here
_supported_fs generic
_supported_os Linux
_require_scratch
_require_test_program "holetest"
rm -f $seqres.full
_scratch_mkfs >>$seqres.full 2>&1
_scratch_mount
src/holetest -f -r $SCRATCH_MNT/testfile 16
src/holetest -f -r $SCRATCH_MNT/testfile 256
src/holetest -f -r -w $SCRATCH_MNT/testfile 16
src/holetest -f -r -w $SCRATCH_MNT/testfile 256
status=0
exit
+73
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@@ -0,0 +1,73 @@
QA output created by 344
INFO: zero-filled test...
INFO: sz = 16777216
INFO: thread 0 created
INFO: thread 1 created
INFO: 0 error(s) detected
INFO: posix_fallocate test...
INFO: sz = 16777216
INFO: thread 0 created
INFO: thread 1 created
INFO: 0 error(s) detected
INFO: ftruncate test...
INFO: sz = 16777216
INFO: thread 0 created
INFO: thread 1 created
INFO: 0 error(s) detected
INFO: zero-filled test...
INFO: sz = 268435456
INFO: thread 0 created
INFO: thread 1 created
INFO: 0 error(s) detected
INFO: posix_fallocate test...
INFO: sz = 268435456
INFO: thread 0 created
INFO: thread 1 created
INFO: 0 error(s) detected
INFO: ftruncate test...
INFO: sz = 268435456
INFO: thread 0 created
INFO: thread 1 created
INFO: 0 error(s) detected
INFO: zero-filled test...
INFO: sz = 16777216
INFO: thread 0 created
INFO: thread 1 created
INFO: 0 error(s) detected
INFO: posix_fallocate test...
INFO: sz = 16777216
INFO: thread 0 created
INFO: thread 1 created
INFO: 0 error(s) detected
INFO: ftruncate test...
INFO: sz = 16777216
INFO: thread 0 created
INFO: thread 1 created
INFO: 0 error(s) detected
INFO: zero-filled test...
INFO: sz = 268435456
INFO: thread 0 created
INFO: thread 1 created
INFO: 0 error(s) detected
INFO: posix_fallocate test...
INFO: sz = 268435456
INFO: thread 0 created
INFO: thread 1 created
INFO: 0 error(s) detected
INFO: ftruncate test...
INFO: sz = 268435456
INFO: thread 0 created
INFO: thread 1 created
INFO: 0 error(s) detected
+1
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@@ -346,6 +346,7 @@
341 auto quick metadata
342 auto quick metadata
343 auto quick metadata
344 auto
346 auto
705 blockdev quick rw
706 blockdev quick rw