Add test which spawns two threads racing to write to file via mmap and
checks the result. This is mainly interesting to uncover races in DAX
fault handling.
Signed-off-by: Jan Kara <jack@xxxxxxx>
---
src/Makefile | 5 +-
src/holetest.c | 342 ++++++++++++++++++++++++++++++++++++++++++++++++++
tests/generic/338 | 57 +++++++++
tests/generic/338.out | 73 +++++++++++
tests/generic/group | 1 +
5 files changed, 476 insertions(+), 2 deletions(-)
create mode 100644 src/holetest.c
create mode 100755 tests/generic/338
create mode 100644 tests/generic/338.out
diff --git a/src/Makefile b/src/Makefile
index 31102086a5f6..1bf318bd068b 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -11,7 +11,8 @@ TARGETS = dirstress fill fill2 getpagesize holes lstat64 \
devzero feature alloc fault fstest t_access_root \
godown resvtest writemod makeextents itrash rename \
multi_open_unlink dmiperf unwritten_sync genhashnames t_holes \
- t_mmap_writev t_truncate_cmtime dirhash_collide t_rename_overwrite
+ t_mmap_writev t_truncate_cmtime dirhash_collide t_rename_overwrite \
+ holetest
LINUX_TARGETS = xfsctl bstat t_mtab getdevicesize preallo_rw_pattern_reader \
preallo_rw_pattern_writer ftrunc trunc fs_perms testx looptest \
@@ -23,7 +24,7 @@ LINUX_TARGETS = xfsctl bstat t_mtab getdevicesize preallo_rw_pattern_reader \
SUBDIRS =
-LLDLIBS = $(LIBATTR) $(LIBHANDLE) $(LIBACL)
+LLDLIBS = $(LIBATTR) $(LIBHANDLE) $(LIBACL) -lpthread
ifeq ($(HAVE_XLOG_ASSIGN_LSN), true)
LINUX_TARGETS += loggen
diff --git a/src/holetest.c b/src/holetest.c
new file mode 100644
index 000000000000..c0a2c67798a3
--- /dev/null
+++ b/src/holetest.c
@@ -0,0 +1,342 @@
+/*
+ * holetest -- test simultaneous page faults on hole-backed pages
+ * Copyright (C) 2015 Hewlett Packard Enterprise Development LP
+ *
+ * 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; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will 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 to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+
+/*
+ * holetest
+ *
+ * gcc -Wall -pthread -o holetest holetest.c
+ *
+ * This test tool exercises page faults on hole-y portions of an mmapped
+ * file. The file is created, sized using various methods, mmapped, and
+ * then two threads race to write a marker to different offsets within
+ * each mapped page. Once the threads have finished marking each page,
+ * the pages are checked for the presence of the markers.
+ *
+ * The file is sized four different ways: explicitly zero-filled by the
+ * test, posix_fallocate(), fallocate(), and ftruncate(). The explicit
+ * zero-fill does not really test simultaneous page faults on hole-backed
+ * pages, but rather serves as control of sorts.
+ *
+ * Usage:
+ *
+ * holetest [-f] FILENAME FILESIZEinMB
+ *
+ * Where:
+ *
+ * FILENAME is the name of a non-existent test file to create
+ *
+ * FILESIZEinMB is the desired size of the test file in MiB
+ *
+ * If the test is successful, FILENAME will be unlinked. By default,
+ * if the test detects an error in the page markers, then the test exits
+ * immediately and FILENAME is left. If -f is given, then the test
+ * continues after a marker error and FILENAME is unlinked, but will
+ * still exit with a non-0 status.
+ */
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <errno.h>
+#include <inttypes.h>
+#include <sys/mman.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <pthread.h>
+#include <string.h>
+
+#define THREADS 2
+
+long page_size;
+long page_offs[THREADS];
+
+void *pt_page_marker(void *args)
+{
+ void **a = args;
+ char *va = (char *)a[0];
+ long npages = (long)a[1];
+ long pgoff = (long)a[2];
+ uint64_t tid = (uint64_t)pthread_self();
+
+ va += pgoff;
+
+ /* mark pages */
+ for (; npages > 0; va += page_size, npages--)
+ *(uint64_t *)(va) = tid;
+
+ return NULL;
+} /* pt_page_marker() */
+
+
+int test_this(int fd, loff_t sz)
+{
+ long npages;
+ char *vastart;
+ char *va;
+ void *targs[THREADS][3];
+ pthread_t t[THREADS];
+ uint64_t tid[THREADS];
+ int errcnt;
+ int i;
+
+ npages = sz / page_size;
+ printf("INFO: sz = %llu\n", (unsigned long long)sz);
+
+ /* mmap it */
+ vastart = mmap(NULL, sz, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
+ if (MAP_FAILED == vastart) {
+ perror("mmap()");
+ exit(20);
+ }
+
+ /* prepare the thread args */
+ for (i = 0; i < THREADS; i++) {
+ targs[i][0] = vastart;
+ targs[i][1] = (void *)npages;
+ targs[i][2] = (void *)page_offs[i];
+ }
+
+ for (i = 0; i < THREADS; i++) {
+ /* start two threads */
+ if (pthread_create(&t[i], NULL, pt_page_marker, &targs[i])) {
+ perror("pthread_create");
+ exit(21);
+ }
+ tid[i] = (uint64_t)t[i];
+ printf("INFO: thread %d created\n", i);
+ }
+
+ /* wait for them to finish */
+ for (i = 0; i < THREADS; i++)
+ pthread_join(t[i], NULL);
+
+ /* check markers on each page */
+ errcnt = 0;
+ for (va = vastart; npages > 0; va += page_size, npages--) {
+ for (i = 0; i < THREADS; i++) {
+ if (*(uint64_t*)(va + page_offs[i]) != tid[i]) {
+ printf("ERROR: thread %d, "
+ "offset %08lx, %08lx != %08lx\n", i,
+ (va + page_offs[i] - vastart),
+ *(uint64_t*)(va + page_offs[i]), tid[i]);
+ errcnt += 1;
+ }
+ }
+ }
+
+ printf("INFO: %d error(s) detected\n", errcnt);
+
+ munmap(vastart, sz);
+
+ return errcnt;
+}
+
+int main(int argc, char **argv)
+{
+ int stoponerror = 1;
+ char *path;
+ loff_t sz;
+ int fd;
+ int errcnt;
+ int toterr = 0;
+ int i, step;
+ char *endch;
+
+ page_size = getpagesize();
+ step = page_size / THREADS;
+ page_offs[0] = step / 2;
+ for (i = 1; i < THREADS; i++)
+ page_offs[i] = page_offs[i-1] + step;
+
+ /* process command line */
+ argc--; argv++;
+ /* ignore errors? */
+ if ((argc == 3) && !strcmp(argv[0], "-f")) {
+ stoponerror = 0;
+ argc--;
+ argv++;
+ }
+ /* file name and size */
+ if (argc != 2 || argv[0][0] == '-') {
+ fprintf(stderr, "ERROR: usage: holetest [-f] "
+ "FILENAME FILESIZEinMB\n");
+ exit(1);
+ }
+ path = argv[0];
+ sz = strtol(argv[1], &endch, 10);
+ if (*endch || sz < 1) {
+ fprintf(stderr, "ERROR: bad FILESIZEinMB\n");
+ exit(1);
+ }
+ sz <<= 20;
+
+ /*
+ * we're going to run our test in several different ways:
+ *
+ * 1. explictly zero-filled
+ * 2. posix_fallocated
+ * 3. fallocated
+ * 4. ftruncated
+ */
+
+
+ /*
+ * explicitly zero-filled
+ */
+ printf("\nINFO: zero-filled test...\n");
+
+ /* create the file */
+ fd = open(path, O_RDWR | O_EXCL | O_CREAT, 0644);
+ if (fd < 0) {
+ perror(path);
+ exit(2);
+ }
+
+ /* truncate it to size */
+ if (ftruncate(fd, sz)) {
+ perror("ftruncate()");
+ exit(3);
+ }
+
+ /* explicitly zero-fill */
+ {
+ char* va = mmap(NULL, sz, PROT_READ | PROT_WRITE,
+ MAP_SHARED, fd, 0);
+ if (MAP_FAILED == va) {
+ perror("mmap()");
+ exit(4);
+ }
+ memset(va, 0, sz);
+ munmap(va, sz);
+ }
+
+ /* test it */
+ errcnt = test_this(fd, sz);
+ toterr += errcnt;
+ close(fd);
+ if (stoponerror && errcnt > 0)
+ exit(5);
+
+ /* cleanup */
+ if (unlink(path)) {
+ perror("unlink()");
+ exit(6);
+ }
+
+
+ /*
+ * posix_fallocated
+ */
+ printf("\nINFO: posix_fallocate test...\n");
+
+ /* create the file */
+ fd = open(path, O_RDWR | O_EXCL | O_CREAT, 0644);
+ if (fd < 0) {
+ perror(path);
+ exit(7);
+ }
+
+ /* fill it to size */
+ if (posix_fallocate(fd, 0, sz)) {
+ perror("posix_fallocate()");
+ exit(8);
+ }
+
+ /* test it */
+ errcnt = test_this(fd, sz);
+ toterr += errcnt;
+ close(fd);
+ if (stoponerror && errcnt > 0)
+ exit(9);
+
+ /* cleanup */
+ if (unlink(path)) {
+ perror("unlink()");
+ exit(10);
+ }
+
+ /*
+ * fallocated
+ */
+ printf("\nINFO: fallocate test...\n");
+
+#ifdef HAVE_FALLOCATE
+ /* create the file */
+ fd = open(path, O_RDWR | O_EXCL | O_CREAT, 0644);
+ if (fd < 0) {
+ perror(path);
+ exit(11);
+ }
+
+ /* fill it to size */
+ if (fallocate(fd, 0, 0, sz)) {
+ perror("fallocate()");
+ exit(12);
+ }
+
+ /* test it */
+ errcnt = test_this(fd, sz);
+ toterr += errcnt;
+ close(fd);
+ if (stoponerror && errcnt > 0)
+ exit(13);
+
+ /* cleanup */
+ if (unlink(path)) {
+ perror("unlink()");
+ exit(14);
+ }
+#endif
+
+ /*
+ * ftruncated
+ */
+ printf("\nINFO: ftruncate test...\n");
+
+ /* create the file */
+ fd = open(path, O_RDWR | O_EXCL | O_CREAT, 0644);
+ if (fd < 0) {
+ perror(path);
+ exit(15);
+ }
+
+ /* truncate it to size */
+ if (ftruncate(fd, sz)) {
+ perror("ftruncate()");
+ exit(16);
+ }
+
+ /* test it */
+ errcnt = test_this(fd, sz);
+ toterr += errcnt;
+ close(fd);
+ if (stoponerror && errcnt > 0)
+ exit(17);
+
+ /* cleanup */
+ if (unlink(path)) {
+ perror("unlink()");
+ exit(18);
+ }
+
+ /* done */
+ if (toterr > 0)
+ exit(19);
+ return 0;
+}
diff --git a/tests/generic/338 b/tests/generic/338
new file mode 100755
index 000000000000..06d787773015
--- /dev/null
+++ b/tests/generic/338
@@ -0,0 +1,57 @@
+#! /bin/bash
+# FSQA Test No. 338
+#
+# Test mmap writing races from racing threads
+#
+#-----------------------------------------------------------------------
+#
+# Copyright (C) 2016 SUSE Linux Products GmbH. All Rights Reserved.
+# Author: Jan Kara <jack@xxxxxxx>
+#
+# 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
+
+rm -f $seqres.full
+
+_scratch_mkfs >>$seqres.full 2>&1
+_scratch_mount
+
+src/holetest -f $SCRATCH_MNT/testfile 1
+src/holetest -f $SCRATCH_MNT/testfile 16
+src/holetest -f $SCRATCH_MNT/testfile 256
+
+status=0
+exit
diff --git a/tests/generic/338.out b/tests/generic/338.out
new file mode 100644
index 000000000000..110203e33d01
--- /dev/null
+++ b/tests/generic/338.out
@@ -0,0 +1,73 @@
+QA output created by 338
+
+INFO: zero-filled test...
+INFO: sz = 1048576
+INFO: thread 0 created
+INFO: thread 1 created
+INFO: 0 error(s) detected
+
+INFO: posix_fallocate test...
+INFO: sz = 1048576
+INFO: thread 0 created
+INFO: thread 1 created
+INFO: 0 error(s) detected
+
+INFO: fallocate test...
+INFO: sz = 1048576
+INFO: thread 0 created
+INFO: thread 1 created
+INFO: 0 error(s) detected
+
+INFO: ftruncate test...
+INFO: sz = 1048576
+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: 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: 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
diff --git a/tests/generic/group b/tests/generic/group
index 727648c68785..4f41631f8adc 100644
--- a/tests/generic/group
+++ b/tests/generic/group
@@ -340,3 +340,4 @@
335 auto quick metadata
336 auto quick metadata
337 auto quick metadata
+338 auto
--
2.6.2
--
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