On Wed, Oct 11, 2017 at 02:52:02PM +0800, Eryu Guan wrote: > From: Zheng Liu <wenqing.lz@xxxxxxxxxx> > > 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 > > Signed-off-by: Zheng Liu <wenqing.lz@xxxxxxxxxx> > Signed-off-by: Eric Sandeen <sandeen@xxxxxxxxxx> > Signed-off-by: Eryu Guan <eguan@xxxxxxxxxx> > --- Looks good, thanks Eryu: Reviewed-by: Brian Foster <bfoster@xxxxxxxxxx> > v3: > - fix reader/writer synchronization race > > v2: > - start background reader in a thread first then start writer only after > reader starts issuing reads > > .gitignore | 1 + > .../aio-dio-append-write-read-race.c | 230 +++++++++++++++++++++ > tests/generic/464 | 75 +++++++ > tests/generic/464.out | 3 + > tests/generic/group | 1 + > 5 files changed, 310 insertions(+) > create mode 100644 src/aio-dio-regress/aio-dio-append-write-read-race.c > create mode 100755 tests/generic/464 > create mode 100644 tests/generic/464.out > > diff --git a/.gitignore b/.gitignore > index ae7ef87ab384..2dface41d485 100644 > --- a/.gitignore > +++ b/.gitignore > @@ -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-cycle-write > /src/aio-dio-regress/aio-dio-eof-race > /src/aio-dio-regress/aio-dio-extend-stat > diff --git a/src/aio-dio-regress/aio-dio-append-write-read-race.c b/src/aio-dio-regress/aio-dio-append-write-read-race.c > new file mode 100644 > index 000000000000..1a78009eb18a > --- /dev/null > +++ b/src/aio-dio-regress/aio-dio-append-write-read-race.c > @@ -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); > +} > diff --git a/tests/generic/464 b/tests/generic/464 > new file mode 100755 > index 000000000000..b0423c91a7cf > --- /dev/null > +++ b/tests/generic/464 > @@ -0,0 +1,75 @@ > +#! /bin/bash > +# FS QA Test No. 464 > +# > +# 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 > diff --git a/tests/generic/464.out b/tests/generic/464.out > new file mode 100644 > index 000000000000..14e66fe7d778 > --- /dev/null > +++ b/tests/generic/464.out > @@ -0,0 +1,3 @@ > +QA output created by 464 > +non-aio dio test > +aio-dio test > diff --git a/tests/generic/group b/tests/generic/group > index 9f173e7a63c9..556add16286b 100644 > --- a/tests/generic/group > +++ b/tests/generic/group > @@ -466,3 +466,4 @@ > 461 auto shutdown stress > 462 auto quick dax > 463 auto rw > +464 auto rw quick aio > -- > 2.13.6 > > -- > To unsubscribe from this list: send the line "unsubscribe fstests" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- 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
