/*
* Copyright (c) 2017 Red Hat Inc. All Rights Reserved.
*
* 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 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, see <http://www.gnu.org/licenses/>.
*
* Author: Xiong Zhou <xzhou@redhat.com>
*
* This is testing OFD locks racing with POSIX locks:
*
* OFD read lock vs OFD write lock
* OFD read lock vs POSIX write lock
* OFD write lock vs POSIX write lock
* OFD write lock vs POSIX read lock
* OFD write lock vs OFD write lock
*
* OFD r/w locks vs POSIX write locks
* OFD r/w locks vs POSIX read locks
*
* For example:
*
* Init an file with preset values.
*
* Threads acquire OFD READ locks to read a 4k section start from 0;
* checking data read back, there should not be any surprise
* values and data should be consistent in a 1k block.
*
* Threads acquire OFD WRITE locks to write a 4k section start from 1k,
* writing different values in different threads.
*
* Check file data after racing, there should not be any surprise values
* and data should be consistent in a 1k block.
*
*
*/
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <pthread.h>
#include <sched.h>
#include <errno.h>
#include "lapi/fcntl.h"
#include "tst_safe_pthread.h"
#include "tst_test.h"
static int thread_cnt;
static int fail_flag = 0;
static volatile int loop_flag = 1;
static const int max_thread_cnt = 32;
static const char fname[] = "tst_ofd_posix_locks";
static const long write_size = 4096;
static pthread_barrier_t barrier;
struct param {
long offset;
long length;
long cnt;
};
static void setup(void)
{
thread_cnt = tst_ncpus_conf() * 3;
if (thread_cnt > max_thread_cnt)
thread_cnt = max_thread_cnt;
}
/* OFD write lock writing data*/
static void *fn_ofd_w(void *arg)
{
struct param *pa = arg;
unsigned char buf[pa->length];
int fd = SAFE_OPEN(fname, O_RDWR);
long wt = pa->cnt;
struct flock64 lck = {
.l_whence = SEEK_SET,
.l_start = pa->offset,
.l_len = pa->length,
.l_pid = 0,
};
while (loop_flag) {
memset(buf, wt, pa->length);
lck.l_type = F_WRLCK;
SAFE_FCNTL(fd, F_OFD_SETLKW, &lck);
SAFE_LSEEK(fd, pa->offset, SEEK_SET);
SAFE_WRITE(1, fd, buf, pa->length);
lck.l_type = F_UNLCK;
SAFE_FCNTL(fd, F_OFD_SETLKW, &lck);
wt++;
if (wt >= 255)
wt = pa->cnt;
sched_yield();
}
pthread_barrier_wait(&barrier);
SAFE_CLOSE(fd);
return NULL;
}
/* POSIX write lock writing data*/
static void *fn_posix_w(void *arg)
{
struct param *pa = arg;
unsigned char buf[pa->length];
int fd = SAFE_OPEN(fname, O_RDWR);
long wt = pa->cnt;
struct flock64 lck = {
.l_whence = SEEK_SET,
.l_start = pa->offset,
.l_len = pa->length,
};
while (loop_flag) {
memset(buf, wt, pa->length);
lck.l_type = F_WRLCK;
SAFE_FCNTL(fd, F_SETLKW, &lck);
SAFE_LSEEK(fd, pa->offset, SEEK_SET);
SAFE_WRITE(1, fd, buf, pa->length);
lck.l_type = F_UNLCK;
SAFE_FCNTL(fd, F_SETLKW, &lck);
wt++;
if (wt >= 255)
wt = pa->cnt;
sched_yield();
}
pthread_barrier_wait(&barrier);
SAFE_CLOSE(fd);
return NULL;
}
/* OFD read lock reading data*/
static void *fn_ofd_r(void *arg)
{
struct param *pa = arg;
unsigned char buf[pa->length];
int i;
int fd = SAFE_OPEN(fname, O_RDWR);
struct flock64 lck = {
.l_whence = SEEK_SET,
.l_start = pa->offset,
.l_len = pa->length,
.l_pid = 0,
};
while (loop_flag) {
memset(buf, 0, pa->length);
lck.l_type = F_RDLCK;
SAFE_FCNTL(fd, F_OFD_SETLKW, &lck);
/* rlock acquired */
SAFE_LSEEK(fd, pa->offset, SEEK_SET);
SAFE_READ(1, fd, buf, pa->length);
/* Verifying data read */
for (i = 0; i < pa->length; i++) {
if (buf[i] < 1 || buf[i] > 254) {
tst_res(TFAIL, "Unexpected data "
"offset %ld value %d",
pa->offset + i, buf[i]);
fail_flag = 1;
break;
}
int j = (i / (pa->length/4)) * pa->length/4;
if (buf[i] != buf[j]) {
tst_res(TFAIL, "Unexpected data "
"offset %ld value %d",
pa->offset + i, buf[i]);
fail_flag = 1;
break;
}
}
lck.l_type = F_UNLCK;
SAFE_FCNTL(fd, F_OFD_SETLK, &lck);
sched_yield();
}
pthread_barrier_wait(&barrier);
SAFE_CLOSE(fd);
return NULL;
}
/* POSIX read lock reading data */
static void *fn_posix_r(void *arg)
{
struct param *pa = arg;
unsigned char buf[pa->length];
int i;
int fd = SAFE_OPEN(fname, O_RDWR);
struct flock64 lck = {
.l_whence = SEEK_SET,
.l_start = pa->offset,
.l_len = pa->length,
};
while (loop_flag) {
memset(buf, 0, pa->length);
lck.l_type = F_RDLCK;
SAFE_FCNTL(fd, F_SETLKW, &lck);
/* rlock acquired */
SAFE_LSEEK(fd, pa->offset, SEEK_SET);
SAFE_READ(1, fd, buf, pa->length);
/* Verifying data read */
for (i = 0; i < pa->length; i++) {
if (buf[i] < 1 || buf[i] > 254) {
tst_res(TFAIL, "Unexpected data "
"offset %ld value %d",
pa->offset + i, buf[i]);
fail_flag = 1;
break;
}
int j = (i / (pa->length/4)) * pa->length/4;
if (buf[i] != buf[j]) {
tst_res(TFAIL, "Unexpected data "
"offset %ld value %d",
pa->offset + i, buf[i]);
fail_flag = 1;
break;
}
}
lck.l_type = F_UNLCK;
SAFE_FCNTL(fd, F_SETLK, &lck);
sched_yield();
}
pthread_barrier_wait(&barrier);
SAFE_CLOSE(fd);
return NULL;
}
static void *fn_dummy(void *arg)
{
arg = NULL;
pthread_barrier_wait(&barrier);
return arg;
}
/* Test different functions and verify data */
static void test_fn(void *f0(void *), void *f1(void *),
void *f2(void *), const char *msg)
{
int i, k, fd;
pthread_t id0[thread_cnt];
pthread_t id1[thread_cnt];
pthread_t id2[thread_cnt];
struct param p0[thread_cnt];
struct param p1[thread_cnt];
struct param p2[thread_cnt];
unsigned char buf[write_size];
tst_res(TINFO, "%s", msg);
if (tst_fill_file(fname, 1, write_size, thread_cnt + 1))
tst_brk(TBROK, "Failed to create tst file");
if (pthread_barrier_init(&barrier, NULL, thread_cnt*3) != 0)
tst_brk(TBROK, "Failed to init pthread barrier");
for (i = 0; i < thread_cnt; i++) {
p0[i].offset = i * write_size;
p0[i].length = write_size;
p0[i].cnt = i + 2;
p1[i].offset = i * write_size + write_size / 4;
p1[i].length = write_size;
p1[i].cnt = i + 2;
p2[i].offset = i * write_size + write_size / 2;
p2[i].length = write_size;
p2[i].cnt = i + 2;
}
fail_flag = 0;
loop_flag = 1;
for (i = 0; i < thread_cnt; i++) {
SAFE_PTHREAD_CREATE(id0 + i, NULL, f0, (void *)&p0[i]);
SAFE_PTHREAD_CREATE(id1 + i, NULL, f1, (void *)&p1[i]);
SAFE_PTHREAD_CREATE(id2 + i, NULL, f2, (void *)&p2[i]);
}
sleep(1);
loop_flag = 0;
for (i = 0; i < thread_cnt; i++) {
SAFE_PTHREAD_JOIN(id0[i], NULL);
SAFE_PTHREAD_JOIN(id1[i], NULL);
SAFE_PTHREAD_JOIN(id2[i], NULL);
}
fd = SAFE_OPEN(fname, O_RDONLY);
for (i = 0; i < thread_cnt * 4; i++) {
SAFE_READ(1, fd, buf, write_size/4);
for (k = 0; k < write_size/4; k++) {
if (buf[k] < 2 || buf[k] > 254) {
if (i < 3 && buf[k] == 1)
continue;
tst_res(TFAIL, "Unexpected data "
"offset %ld value %d",
i * write_size / 4 + k, buf[k]);
SAFE_CLOSE(fd);
return;
}
}
for (k = 1; k < write_size/4; k++) {
if (buf[k] != buf[0]) {
tst_res(TFAIL, "Unexpected block read");
SAFE_CLOSE(fd);
return;
}
}
}
if (pthread_barrier_destroy(&barrier) != 0)
tst_brk(TBROK, "Failed to destroy pthread barrier");
SAFE_CLOSE(fd);
if (fail_flag == 0)
tst_res(TPASS, "Access between threads synchronized");
}
static struct tcase {
void *(*fn0)(void *);
void *(*fn1)(void *);
void *(*fn2)(void *);
const char *desc;
} tcases[] = {
{fn_ofd_r, fn_ofd_w, fn_dummy, "OFD read lock vs OFD write lock"},
{fn_ofd_w, fn_posix_w, fn_dummy, "OFD write lock vs POSIX write lock"},
{fn_ofd_r, fn_posix_w, fn_dummy, "OFD read lock vs POSIX write lock"},
{fn_ofd_w, fn_posix_r, fn_dummy, "OFD write lock vs POSIX read lock"},
{fn_ofd_w, fn_ofd_w, fn_dummy, "OFD write lock vs OFD write lock"},
{fn_ofd_r, fn_ofd_w, fn_posix_w, "OFD r/w lock vs POSIX write lock"},
{fn_ofd_r, fn_ofd_w, fn_posix_r, "OFD r/w lock vs POSIX read lock"},
};
static void tests(unsigned int i)
{
test_fn(tcases[i].fn0, tcases[i].fn1, tcases[i].fn2, tcases[i].desc);
}
static struct tst_test test = {
.min_kver = "3.15",
.needs_tmpdir = 1,
.test = tests,
.tcnt = ARRAY_SIZE(tcases),
.setup = setup
};