1 files changed, 303 insertions, 0 deletions
diff --git a/ctdb/utils/ping_pong/ping_pong.c b/ctdb/utils/ping_pong/ping_pong.c
new file mode 100644
index 0000000..3d28f34
--- /dev/null
+++ b/ctdb/utils/ping_pong/ping_pong.c
@@ -0,0 +1,303 @@
+/*
+   A ping-pong fcntl byte range lock test
+
+   Copyright (C) Andrew Tridgell 2002
+   Copyright (C) Michael Adam 2012
+
+   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 3 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, see <http://www.gnu.org/licenses/>.
+*/
+
+/*
+  This measures the ping-pong byte range lock latency. It is
+  especially useful on a cluster of nodes sharing a common lock
+  manager as it will give some indication of the lock managers
+  performance under stress.
+
+  tridge@samba.org, February 2002
+
+*/
+
+#define _XOPEN_SOURCE 500
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/time.h>
+#include <time.h>
+#include <errno.h>
+#include <string.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/mman.h>
+#include <stdbool.h>
+
+static struct timeval tp1,tp2;
+
+static int do_reads, do_writes, use_mmap, do_check, do_brl_test;
+
+static void start_timer(void)
+{
+	gettimeofday(&tp1,NULL);
+}
+
+static double end_timer(void)
+{
+	gettimeofday(&tp2,NULL);
+	return (tp2.tv_sec + (tp2.tv_usec*1.0e-6)) - 
+		(tp1.tv_sec + (tp1.tv_usec*1.0e-6));
+}
+
+/* lock a byte range in a open file */
+static int lock_range(int fd, int offset, int len, bool wait)
+{
+	struct flock lock;
+
+	lock.l_type = F_WRLCK;
+	lock.l_whence = SEEK_SET;
+	lock.l_start = offset;
+	lock.l_len = len;
+	lock.l_pid = 0;
+	
+	return fcntl(fd, wait ? F_SETLKW : F_SETLK, &lock);
+}
+
+/* check whether we could place a lock */
+static int check_lock(int fd, int offset, int len)
+{
+	struct flock lock;
+	int ret;
+
+	lock.l_type = F_WRLCK;
+	lock.l_whence = SEEK_SET;
+	lock.l_start = offset;
+	lock.l_len = len;
+	lock.l_pid = 0;
+
+	ret = fcntl(fd, F_GETLK, &lock);
+	if (ret != 0) {
+		printf("error calling fcntl F_GETLCK: %s\n", strerror(errno));
+		return -1;
+	}
+
+	if (lock.l_type == F_UNLCK) {
+		/* we would be able to place the lock */
+		return 0;
+	}
+
+	/* we would not be able to place lock */
+	printf("check_lock failed: lock held: "
+	       "pid='%d', type='%d', start='%d', len='%d'\n",
+	       (int)lock.l_pid, (int)lock.l_type, (int)lock.l_start, (int)lock.l_len);
+	return 1;
+}
+
+/* unlock a byte range in a open file */
+static int unlock_range(int fd, int offset, int len)
+{
+	struct flock lock;
+
+	lock.l_type = F_UNLCK;
+	lock.l_whence = SEEK_SET;
+	lock.l_start = offset;
+	lock.l_len = len;
+	lock.l_pid = 0;
+	
+	return fcntl(fd,F_SETLKW,&lock);
+}
+
+/* run the ping pong test on fd */
+static void ping_pong(int fd, int num_locks)
+{
+	unsigned count = 0;
+	int i=0, loops=0;
+	unsigned char *val;
+	unsigned char incr=0, last_incr=0;
+	unsigned char *p = NULL;
+	int ret;
+
+	ret = ftruncate(fd, num_locks+1);
+	if (ret == -1) {
+		printf("ftruncate failed: %s\n", strerror(errno));
+		return;
+	}
+
+	if (use_mmap) {
+		p = mmap(NULL, num_locks+1, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
+		if (p == MAP_FAILED) {
+			printf("mmap failed: %s\n", strerror(errno));
+			return;
+		}
+	}
+
+	val = (unsigned char *)calloc(num_locks+1, sizeof(unsigned char));
+	if (val == NULL) {
+		printf("calloc failed\n");
+		if (use_mmap) {
+			munmap(p, num_locks+1);
+		}
+		return;
+	}
+
+	start_timer();
+
+	ret = lock_range(fd, 0, 1, true);
+	if (ret != 0) {
+		printf("initial lock at 0 failed! - %s\n", strerror(errno));
+		goto done;
+	}
+
+	i = 0;
+
+	while (1) {
+		if (lock_range(fd, (i+1) % num_locks, 1, true) != 0) {
+			printf("lock at %d failed! - %s\n",
+			       (i+1) % num_locks, strerror(errno));
+		}
+		if (do_check) {
+			ret = check_lock(fd, i, 1);
+			if (ret != 0) {
+				goto done;
+			}
+		}
+		if (do_reads) {
+			unsigned char c;
+			if (use_mmap) {
+				c = p[i];
+			} else if (pread(fd, &c, 1, i) != 1) {
+				printf("read failed at %d\n", i);
+			}
+			incr = c - val[i];
+			val[i] = c;
+		}
+		if (do_writes) {
+			char c = val[i] + 1;
+			if (use_mmap) {
+				p[i] = c;
+			} else if (pwrite(fd, &c, 1, i) != 1) {
+				printf("write failed at %d\n", i);
+			}
+		}
+		if (unlock_range(fd, i, 1) != 0) {
+			printf("unlock at %d failed! - %s\n",
+			       i, strerror(errno));
+		}
+		i = (i+1) % num_locks;
+		count++;
+		if (loops > num_locks && incr != last_incr) {
+			last_incr = incr;
+			printf("data increment = %u\n", incr);
+			fflush(stdout);
+		}
+		if (end_timer() > 1.0) {
+			printf("%8u locks/sec\r", 
+			       (unsigned)(2*count/end_timer()));
+			fflush(stdout);
+			start_timer();
+			count=0;
+		}
+		loops++;
+	}
+
+done:
+	if (use_mmap) {
+		munmap(p, num_locks+1);
+	}
+	free(val);
+}
+
+static void usage(void)
+{
+	printf("ping_pong -rwmc <file> <num_locks>\n");
+	printf("ping_pong -l <file>\n\n");
+	printf("Options\n");
+	printf(" -r    do reads\n");
+	printf(" -w    do writes\n");
+	printf(" -m    use mmap\n");
+	printf(" -c    check locks\n");
+	printf(" -l    test for working byte range locks\n");
+}
+
+int main(int argc, char *argv[])
+{
+	char *fname;
+	int fd, num_locks;
+	int c;
+
+	while ((c = getopt(argc, argv, "rwmcl")) != -1) {
+		switch (c){
+		case 'w':
+			do_writes = 1;
+			break;
+		case 'r':
+			do_reads = 1;
+			break;
+		case 'm':
+			use_mmap = 1;
+			break;
+		case 'c':
+			do_check = 1;
+			break;
+		case 'l':
+			do_brl_test = 1;
+			break;
+		default:
+			fprintf(stderr, "Unknown option '%c'\n", c);
+			exit(1);
+		}
+	}
+
+	argv += optind;
+	argc -= optind;
+
+	if (argc < 1) {
+		usage();
+		exit(1);
+	}
+
+	fname = argv[0];
+
+	fd = open(fname, O_CREAT|O_RDWR, 0600);
+	if (fd == -1) {
+		exit(1);
+	}
+
+	if (do_brl_test) {
+		if (lock_range(fd, 0, 0, false) != 0) {
+			printf("file already locked, calling check_lock to tell us who has it locked:\n");
+			(void)check_lock(fd, 0, 0);
+			printf("Working POSIX byte range locks\n");
+			exit(0);
+		}
+
+		printf("Holding lock, press any key to continue...\n");
+		printf("You should run the same command on another node now.\n");
+		(void)getchar();
+		printf("Good bye.\n");
+		exit(0);
+	}
+
+	if (argc < 2) {
+		usage();
+		exit(1);
+	}
+
+	num_locks = atoi(argv[1]);
+	if (num_locks <= 0) {
+		printf("num_locks should be > 0\n");
+		exit(1);
+	}
+
+	ping_pong(fd, num_locks);
+
+	return 0;
+}