diff options
Diffstat (limited to 'tests/zfs-tests/cmd/mmapwrite/mmapwrite.c')
| -rw-r--r-- | tests/zfs-tests/cmd/mmapwrite/mmapwrite.c | 162 |
1 files changed, 162 insertions, 0 deletions
diff --git a/tests/zfs-tests/cmd/mmapwrite/mmapwrite.c b/tests/zfs-tests/cmd/mmapwrite/mmapwrite.c new file mode 100644 index 000000000000..458d6d8e402b --- /dev/null +++ b/tests/zfs-tests/cmd/mmapwrite/mmapwrite.c @@ -0,0 +1,162 @@ +/* + * CDDL HEADER START + * + * The contents of this file are subject to the terms of the + * Common Development and Distribution License (the "License"). + * You may not use this file except in compliance with the License. + * + * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE + * or http://www.opensolaris.org/os/licensing. + * See the License for the specific language governing permissions + * and limitations under the License. + * + * When distributing Covered Code, include this CDDL HEADER in each + * file and include the License file at usr/src/OPENSOLARIS.LICENSE. + * If applicable, add the following below this CDDL HEADER, with the + * fields enclosed by brackets "[]" replaced with your own identifying + * information: Portions Copyright [yyyy] [name of copyright owner] + * + * CDDL HEADER END + */ + +/* + * Copyright 2007 Sun Microsystems, Inc. All rights reserved. + * Use is subject to license terms. + */ + +#include <unistd.h> +#include <fcntl.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <sys/mman.h> +#include <pthread.h> +#include <errno.h> +#include <err.h> + +/* + * -------------------------------------------------------------------- + * Bug Issue Id: #7512 + * The bug time sequence: + * 1. context #1, zfs_write assign a txg "n". + * 2. In the same process, context #2, mmap page fault (which means the mm_sem + * is hold) occurred, zfs_dirty_inode open a txg failed, and wait previous + * txg "n" completed. + * 3. context #1 call uiomove to write, however page fault is occurred in + * uiomove, which means it needs mm_sem, but mm_sem is hold by + * context #2, so it stuck and can't complete, then txg "n" will not + * complete. + * + * So context #1 and context #2 trap into the "dead lock". + * -------------------------------------------------------------------- + */ + +#define NORMAL_WRITE_TH_NUM 2 + +static void * +normal_writer(void *filename) +{ + char *file_path = filename; + int fd = -1; + ssize_t write_num = 0; + int page_size = getpagesize(); + + fd = open(file_path, O_RDWR | O_CREAT, 0777); + if (fd == -1) { + err(1, "failed to open %s", file_path); + } + + char *buf = malloc(1); + while (1) { + write_num = write(fd, buf, 1); + if (write_num == 0) { + err(1, "write failed!"); + break; + } + lseek(fd, page_size, SEEK_CUR); + } + + if (buf) { + free(buf); + } +} + +static void * +map_writer(void *filename) +{ + int fd = -1; + int ret = 0; + char *buf = NULL; + int page_size = getpagesize(); + int op_errno = 0; + char *file_path = filename; + + while (1) { + ret = access(file_path, F_OK); + if (ret) { + op_errno = errno; + if (op_errno == ENOENT) { + fd = open(file_path, O_RDWR | O_CREAT, 0777); + if (fd == -1) { + err(1, "open file failed"); + } + + ret = ftruncate(fd, page_size); + if (ret == -1) { + err(1, "truncate file failed"); + } + } else { + err(1, "access file failed!"); + } + } else { + fd = open(file_path, O_RDWR, 0777); + if (fd == -1) { + err(1, "open file failed"); + } + } + + if ((buf = mmap(NULL, page_size, PROT_READ | PROT_WRITE, + MAP_SHARED, fd, 0)) == MAP_FAILED) { + err(1, "map file failed"); + } + + if (fd != -1) + close(fd); + + char s[10] = {0, }; + memcpy(buf, s, 10); + ret = munmap(buf, page_size); + if (ret != 0) { + err(1, "unmap file failed"); + } + } +} + +int +main(int argc, char **argv) +{ + pthread_t map_write_tid; + pthread_t normal_write_tid[NORMAL_WRITE_TH_NUM]; + int i = 0; + + if (argc != 3) { + (void) printf("usage: %s <normal write file name>" + "<map write file name>\n", argv[0]); + exit(1); + } + + for (i = 0; i < NORMAL_WRITE_TH_NUM; i++) { + if (pthread_create(&normal_write_tid[i], NULL, normal_writer, + argv[1])) { + err(1, "pthread_create normal_writer failed."); + } + } + + if (pthread_create(&map_write_tid, NULL, map_writer, argv[2])) { + err(1, "pthread_create map_writer failed."); + } + + /* NOTREACHED */ + pthread_join(map_write_tid, NULL); + return (0); +} |