| /* |
| * 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. |
| */ |
| |
| /* |
| * Copyright (c) 2013 by Delphix. All rights reserved. |
| */ |
| |
| #include <sys/types.h> |
| #include <sys/stat.h> |
| #include <fcntl.h> |
| #include <pthread.h> |
| #include <string.h> |
| #include <stdio.h> |
| #include <unistd.h> |
| #include <stdlib.h> |
| #include <errno.h> |
| |
| /* |
| * The size of the output file, "go.out", should be 80*8192*2 = 1310720 |
| * |
| * $ cd /tmp; go; ls -l go.out |
| * done. |
| * -rwxr-xr-x 1 jdm staff 1310720 Apr 13 19:45 go.out |
| * $ cd /zfs; go; ls -l go.out |
| * done. |
| * -rwxr-xr-x 1 jdm staff 663552 Apr 13 19:45 go.out |
| * |
| * The file on zfs is short as it does not appear that zfs is making the |
| * implicit seek to EOF and the actual write atomic. From the SUSv3 |
| * interface spec, behavior is undefined if concurrent writes are performed |
| * from multi-processes to a single file. So I don't know if this is a |
| * standards violation, but I cannot find any such disclaimers in our |
| * man pages. This issue came up at a customer site in another context, and |
| * the suggestion was to open the file with O_APPEND, but that wouldn't |
| * help with zfs(see 4977529). Also see bug# 5031301. |
| */ |
| |
| static int outfd = 0; |
| |
| static void * |
| go(void *data) |
| { |
| int ret, i = 0, n = *(int *)data; |
| char buf[8192] = {0}; |
| (void) memset(buf, n, sizeof (buf)); |
| |
| for (i = 0; i < 80; i++) { |
| ret = write(outfd, buf, sizeof (buf)); |
| if (ret != sizeof (buf)) |
| perror("write"); |
| } |
| return (NULL); |
| } |
| |
| static void |
| usage(void) |
| { |
| (void) fprintf(stderr, |
| "usage: zfs_threadsappend <file name>\n"); |
| exit(1); |
| } |
| |
| int |
| main(int argc, char **argv) |
| { |
| pthread_t tid; |
| int ret = 0; |
| long ncpus = 0; |
| int i; |
| |
| if (argc != 2) { |
| usage(); |
| } |
| |
| ncpus = sysconf(_SC_NPROCESSORS_ONLN); |
| if (ncpus < 0) { |
| (void) fprintf(stderr, |
| "Invalid return from sysconf(_SC_NPROCESSORS_ONLN)" |
| " : errno (decimal)=%d\n", errno); |
| exit(1); |
| } |
| if (ncpus < 2) { |
| (void) fprintf(stderr, |
| "Must execute this binary on a multi-processor system\n"); |
| exit(1); |
| } |
| |
| outfd = open(argv[optind++], O_RDWR|O_CREAT|O_APPEND|O_TRUNC, 0777); |
| if (outfd == -1) { |
| (void) fprintf(stderr, |
| "zfs_threadsappend: " |
| "open(%s, O_RDWR|O_CREAT|O_APPEND|O_TRUNC, 0777)" |
| " failed\n", argv[optind]); |
| perror("open"); |
| exit(1); |
| } |
| |
| for (i = 0; i < 2; i++) { |
| ret = pthread_create(&tid, NULL, go, (void *)&i); |
| if (ret != 0) { |
| (void) fprintf(stderr, |
| "zfs_threadsappend: thr_create(#%d) " |
| "failed error=%d\n", i+1, ret); |
| exit(1); |
| } |
| } |
| |
| while (pthread_join(tid, NULL) == 0) |
| continue; |
| |
| return (0); |
| } |