Add a "threads" parameter too openclose, so you can easily launch lots of

threads.

lustre/tests/openclose.c

@@ -6,6 +6,7 @@
 #include <fcntl.h>
 #include <errno.h>
 #include <string.h>
+#include <sys/wait.h>
 
 #ifndef O_DIRECT
 #define O_DIRECT         040000 /* direct disk access hint */
@@ -13,45 +14,117 @@
 
 int main(int argc, char *argv[])
 {
-        char *filename;
+        char filename[1024];
         unsigned long count, i;
+	int thread = 0;
+	int threads = 0;
+	int rc;
         int fd;
 
-        if (argc != 3) {
-                fprintf(stderr, "usage: %s <filename> <iterations>\n", argv[0]);
+        if (argc < 3 || argc > 4) {
+                fprintf(stderr, "usage: %s <filename> <iterations> [threads]\n",
+			argv[0]);
                 exit(1);
         }
 
-        filename = argv[1];
         count = strtoul(argv[2], NULL, 0);
+	if (argc == 4)
+		threads = strtoul(argv[3], NULL, 0);
 
-        fd = open(filename, O_RDWR|O_CREAT, 0644);
-        if (fd < 0) {
-                fprintf(stderr, "open(%s, O_CREAT): %s\n", filename,
-                        strerror(errno));
-                exit(1);
-        }
-        if (close(fd) < 0) {
-                fprintf(stderr, "close(): %s\n", strerror(errno));
-                exit(1);
+        for (i = 1; i <= threads; i++) {
+                rc = fork();
+                if (rc < 0) {
+                        fprintf(stderr, "error: %s: #%ld - %s\n", argv[0], i,
+                                strerror(rc = errno));
+                        break;
+                } else if (rc == 0) {
+                        thread = i;
+                        argv[2] = "--device";
+                        break;
+                } else
+                        printf("%s: thread #%ld (PID %d) started\n",
+                               argv[0], i, rc);
+                rc = 0;
         }
 
-        for (i = 0; i < count; i++) {
-                fd = open(filename, O_RDONLY|O_LARGEFILE|O_DIRECT);
-                if (fd < 0) {
-                        fprintf(stderr, "open(%s, O_RDONLY): %s\n", filename,
-                                strerror(errno));
-                        exit(1);
-                }
-                if (close(fd) < 0) {
-                        fprintf(stderr, "close(): %s\n", strerror(errno));
-                        exit(1);
+        if (threads && thread == 0) {	/* parent process */
+                int live_threads = threads;
+
+                while (live_threads > 0) {
+                        int status;
+                        pid_t ret;
+
+                        ret = waitpid(0, &status, 0);
+                        if (ret == 0) {
+                                continue;
+                        }
+
+                        if (ret < 0) {
+                                fprintf(stderr, "error: %s: wait - %s\n",
+                                        argv[0], strerror(errno));
+                                if (!rc)
+                                        rc = errno;
+                        } else {
+                                /*
+                                 * This is a hack.  We _should_ be able to use
+                                 * WIFEXITED(status) to see if there was an
+                                 * error, but it appears to be broken and it
+                                 * always returns 1 (OK).  See wait(2).
+                                 */
+                                int err = WEXITSTATUS(status);
+                                if (err || WIFSIGNALED(status))
+                                        fprintf(stderr,
+                                                "%s: PID %d had rc=%d\n",
+                                                argv[0], ret, err);
+                                if (!rc)
+                                        rc = err;
+
+                                live_threads--;
+                        }
                 }
-        }
-        if (unlink(filename) < 0) {
-                fprintf(stderr, "unlink(%s): %s\n", filename, strerror(errno));
-                exit(1);
-        }
-        printf("Done.\n");
-        return 0;
+	} else {
+		if (threads)
+			sprintf(filename, "%s-%d", argv[1], thread);
+		else
+			strcpy(filename, argv[1]);
+
+		fd = open(filename, O_RDWR|O_CREAT, 0644);
+		if (fd < 0) {
+			fprintf(stderr, "open(%s, O_CREAT): %s\n", filename,
+				strerror(errno));
+			exit(errno);
+		}
+		if (close(fd) < 0) {
+			fprintf(stderr, "close(): %s\n", strerror(errno));
+			rc = errno;
+			goto unlink;
+		}
+
+		for (i = 0; i < count; i++) {
+			fd = open(filename, O_RDWR|O_LARGEFILE|O_DIRECT);
+			if (fd < 0) {
+				fprintf(stderr, "open(%s, O_RDWR): %s\n",
+					filename, strerror(errno));
+				rc = errno;
+				break;
+			}
+			if (close(fd) < 0) {
+				fprintf(stderr, "close(): %s\n",
+					strerror(errno));
+				rc = errno;
+				break;
+			}
+		}
+	unlink:
+		if (unlink(filename) < 0) {
+			fprintf(stderr, "unlink(%s): %s\n", filename,
+				strerror(errno));
+			rc = errno;
+		}
+		if (threads)
+			printf("Thread %d done: rc = %d\n", thread, rc);
+		else
+			printf("Done: rc = %d\n", rc);
+	}
+        return rc;
 }