generic: test race when checking i_size on direct i/o read

In this commit a new test case is added to test that i_size races
don't occur under dio reads/writes.  We add a program in /src dir,
which has a writer to issue some append dio writes.  Meanwhile it
has a reader in this test to do some dio reads.  As we expect,
reader should read nothing or data with 'a'. But it might read some
data with '0'.

The bug can be reproduced by this test case [1].

1.  http://patchwork.ozlabs.org/patch/311761/

This ostensibly tests commit:
9fe55eea7 Fix race when checking i_size on direct i/o read

Update by Eric Sandeen:
- update to recent xfstests
- update commit log

Update by Eryu Guan:
- add aio-dio support to the test and add 'aio' group
- add ability to test different alignments
- move test from src/ to src/aio-dio-regress/
- add .gitignore entry
- rebase against latest xfstests with various minor fixes & cleanups
- update commit log

Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Zheng Liu <wenqing.lz@taobao.com>
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Eryu Guan <eguan@redhat.com>
This commit is contained in:
Zheng Liu
2017-08-18 15:35:02 -05:00
committed by Eryu Guan
parent a6479f7646
commit 21db51dd98
5 changed files with 310 additions and 0 deletions
+1
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@@ -142,6 +142,7 @@
/src/writemod
/src/writev_on_pagefault
/src/xfsctl
/src/aio-dio-regress/aio-dio-append-write-read-race
/src/aio-dio-regress/aio-dio-cow-race
/src/aio-dio-regress/aio-dio-cycle-write
/src/aio-dio-regress/aio-dio-eof-race
@@ -0,0 +1,230 @@
/*
* Copyright (c) 2013 Alibaba Group.
* 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
*/
/*
* This is a normal case that we do some append dio writes and meanwhile
* we do some dio reads. Currently in vfs we don't ensure that i_size
* is updated properly. Hence the reader will read some data with '0'.
* But we expect that the reader should read nothing or data with 'a'.
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <errno.h>
#include <libaio.h>
#include <pthread.h>
struct io_data {
int fd;
size_t blksize;
off_t offset;
char *buf;
int use_aio;
};
int reader_ready = 0;
static void usage(const char *prog)
{
fprintf(stderr, "usage: %s [-a] <file>\n", prog);
fprintf(stderr, "\t-a\tuse aio-dio\n");
exit(EXIT_FAILURE);
}
static void *reader(void *arg)
{
struct io_data *data = (struct io_data *)arg;
int ret;
memset(data->buf, 'b', data->blksize);
reader_ready = 1;
do {
ret = pread(data->fd, data->buf, data->blksize, data->offset);
if (ret < 0)
perror("read file");
} while (ret <= 0);
return NULL;
}
static void *writer(struct io_data *data)
{
int ret;
while (!reader_ready)
usleep(1);
if (data->use_aio) {
struct io_context *ctx = NULL;
struct io_event evs[1];
struct iocb iocb;
struct iocb *iocbs[] = { &iocb };
ret = io_setup(1, &ctx);
if (ret) {
fprintf(stderr, "error %s during io_setup\n",
strerror(ret));
return NULL;
}
io_prep_pwrite(&iocb, data->fd, data->buf, data->blksize, data->offset);
ret = io_submit(ctx, 1, iocbs);
if (ret != 1) {
fprintf(stderr, "error %s during io_submit\n",
strerror(ret));
return NULL;
}
ret = io_getevents(ctx, 1, 1, evs, NULL);
if (ret != 1) {
fprintf(stderr, "error %s during io_getevents\n",
strerror(ret));
return NULL;
}
} else {
ret = pwrite(data->fd, data->buf, data->blksize, data->offset);
if (ret < 0)
perror("write file failed");
}
return NULL;
}
int main(int argc, char *argv[])
{
pthread_t tid;
struct io_data wdata;
struct io_data rdata;
size_t max_blocks = 128; /* 128 */
size_t blksize = 1 * 1024 * 1024; /* 1M */
char *rbuf = NULL, *wbuf = NULL;
int rfd = 0, wfd = 0;
int i, j, c;
int use_aio = 1;
int ret = 0;
int io_align = 4096;
char *prog;
char *testfile;
prog = basename(argv[0]);
while ((c = getopt(argc, argv, "a:d")) != -1) {
switch (c) {
case 'a':
io_align = strtol(optarg, NULL, 0);
break;
case 'd':
use_aio = 0;
break;
default:
usage(prog);
}
}
if (optind != argc - 1)
usage(prog);
testfile = argv[optind];
wfd = open(testfile, O_CREAT|O_DIRECT|O_WRONLY|O_TRUNC, 0644);
if (wfd < 0) {
perror("open for write");
exit(1);
}
rfd = open(testfile, O_DIRECT|O_RDONLY, 0644);
if (rfd < 0) {
perror("open for read");
ret = 1;
goto err;
}
ret = posix_memalign((void **)&wbuf, io_align, blksize);
if (ret) {
fprintf(stderr, "failed to alloc memory: %s\n", strerror(ret));
ret = 1;
goto err;
}
ret = posix_memalign((void **)&rbuf, io_align, blksize);
if (ret) {
fprintf(stderr, "failed to alloc memory: %s\n", strerror(ret));
ret = 1;
goto err;
}
memset(wbuf, 'a', blksize);
wdata.fd = wfd;
wdata.blksize = blksize;
wdata.buf = wbuf;
wdata.use_aio = use_aio;
rdata.fd = rfd;
rdata.blksize = blksize;
rdata.buf = rbuf;
for (i = 0; i < max_blocks; i++) {
wdata.offset = rdata.offset = i * blksize;
/* reset reader_ready, it will be set in reader thread */
reader_ready = 0;
ret = pthread_create(&tid, NULL, reader, &rdata);
if (ret) {
fprintf(stderr, "create reader thread failed: %s\n",
strerror(ret));
ret = 1;
goto err;
}
writer(&wdata);
ret = pthread_join(tid, NULL);
if (ret) {
fprintf(stderr, "pthread join reader failed: %s\n",
strerror(ret));
ret = 1;
goto err;
}
for (j = 0; j < blksize; j++) {
if (rdata.buf[j] != 'a') {
fprintf(stderr, "encounter an error: "
"block %d offset %d, content %x\n",
i, j, rbuf[j]);
ret = 1;
goto err;
}
}
}
err:
if (rfd)
close(rfd);
if (wfd)
close(wfd);
if (rbuf)
free(rbuf);
if (wbuf)
free(wbuf);
exit(ret);
}
+75
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@@ -0,0 +1,75 @@
#! /bin/bash
# FS QA Test No. 465
#
# Test i_size is updated properly under dio read/write
#
#-----------------------------------------------------------------------
# Copyright (c) 2013 Alibaba Group. All Rights Reserved.
# 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/$$
status=1 # failure is the default!
trap "_cleanup; exit \$status" 0 1 2 3 15
_cleanup()
{
cd /
rm -f $tmp.* $testfile.*
}
# get standard environment, filters and checks
. ./common/rc
. ./common/filter
# real QA test starts here
_supported_fs generic
_supported_os Linux
_require_aiodio aio-dio-append-write-read-race
_require_test_program "feature"
testfile=$TEST_DIR/$seq.$$
min_dio_align=`_min_dio_alignment $TEST_DEV`
page_size=`$here/src/feature -s`
rm -f $seqres.full
echo "non-aio dio test"
align=$min_dio_align
while [ $align -le $page_size ]; do
echo "$AIO_TEST -a $align -d $testfile.$align" >> $seqres.full
$AIO_TEST -a $align -d $testfile.$align 2>&1 | tee -a $seqres.full
align=$((align * 2))
done
echo "aio-dio test"
align=$min_dio_align
while [ $align -le $page_size ]; do
echo "$AIO_TEST -a $align $testfile.$align" >> $seqres.full
$AIO_TEST -a $align $testfile.$align 2>&1 | tee -a $seqres.full
align=$((align * 2))
done
# success, all done
status=0
exit
+3
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@@ -0,0 +1,3 @@
QA output created by 465
non-aio dio test
aio-dio test
+1
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@@ -467,3 +467,4 @@
462 auto quick dax
463 auto quick clone dangerous
464 auto rw
465 auto rw quick aio