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#include "../config-host.h"
/* SPDX-License-Identifier: MIT */
/*
* Description: test many files being polled for and updated
*
*/
#include <errno.h>
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <signal.h>
#include <poll.h>
#include <sys/resource.h>
#include <fcntl.h>
#include <pthread.h>
#include "liburing.h"
#define NFILES 5000
#define BATCH 500
#define NLOOPS 1000
#define RING_SIZE 512
struct p {
int fd[2];
int triggered;
};
static struct p p[NFILES];
static int has_poll_update(void)
{
struct io_uring ring;
struct io_uring_cqe *cqe;
struct io_uring_sqe *sqe;
bool has_update = false;
int ret;
ret = io_uring_queue_init(8, &ring, 0);
if (ret)
return -1;
sqe = io_uring_get_sqe(&ring);
io_uring_prep_poll_update(sqe, 0, 0, POLLIN, IORING_TIMEOUT_UPDATE);
ret = io_uring_submit(&ring);
if (ret != 1)
return -1;
ret = io_uring_wait_cqe(&ring, &cqe);
if (!ret) {
if (cqe->res == -ENOENT)
has_update = true;
else if (cqe->res != -EINVAL)
return -1;
io_uring_cqe_seen(&ring, cqe);
}
io_uring_queue_exit(&ring);
return has_update;
}
static int arm_poll(struct io_uring *ring, int off)
{
struct io_uring_sqe *sqe;
sqe = io_uring_get_sqe(ring);
if (!sqe) {
fprintf(stderr, "failed getting sqe\n");
return 1;
}
io_uring_prep_poll_multishot(sqe, p[off].fd[0], POLLIN);
sqe->user_data = off;
return 0;
}
static int submit_arm_poll(struct io_uring *ring, int off)
{
int ret;
ret = arm_poll(ring, off);
if (ret)
return ret;
ret = io_uring_submit(ring);
if (ret < 0)
return ret;
return ret == 1 ? 0 : -1;
}
static int reap_polls(struct io_uring *ring)
{
struct io_uring_cqe *cqe;
int i, ret, off;
char c;
for (i = 0; i < BATCH; i++) {
struct io_uring_sqe *sqe;
sqe = io_uring_get_sqe(ring);
/* update event */
io_uring_prep_poll_update(sqe, i, 0, POLLIN,
IORING_POLL_UPDATE_EVENTS);
sqe->user_data = 0x12345678;
}
ret = io_uring_submit(ring);
if (ret != BATCH) {
fprintf(stderr, "submitted %d, %d\n", ret, BATCH);
return 1;
}
for (i = 0; i < 2 * BATCH; i++) {
ret = io_uring_wait_cqe(ring, &cqe);
if (ret) {
fprintf(stderr, "wait cqe %d\n", ret);
return ret;
}
off = cqe->user_data;
if (off == 0x12345678)
goto seen;
if (!(cqe->flags & IORING_CQE_F_MORE)) {
/* need to re-arm poll */
ret = submit_arm_poll(ring, off);
if (ret)
break;
if (cqe->res <= 0) {
/* retry this one */
i--;
goto seen;
}
}
ret = read(p[off].fd[0], &c, 1);
if (ret != 1) {
if (ret == -1 && errno == EAGAIN)
goto seen;
fprintf(stderr, "read got %d/%d\n", ret, errno);
break;
}
seen:
io_uring_cqe_seen(ring, cqe);
}
if (i != 2 * BATCH) {
fprintf(stderr, "gave up at %d\n", i);
return 1;
}
return 0;
}
static int trigger_polls(void)
{
char c = 89;
int i, ret;
for (i = 0; i < BATCH; i++) {
int off;
do {
off = rand() % NFILES;
if (!p[off].triggered)
break;
} while (1);
p[off].triggered = 1;
ret = write(p[off].fd[1], &c, 1);
if (ret != 1) {
fprintf(stderr, "write got %d/%d\n", ret, errno);
return 1;
}
}
return 0;
}
static void *trigger_polls_fn(void *data)
{
trigger_polls();
return NULL;
}
static int arm_polls(struct io_uring *ring)
{
int ret, to_arm = NFILES, i, off;
off = 0;
while (to_arm) {
int this_arm;
this_arm = to_arm;
if (this_arm > RING_SIZE)
this_arm = RING_SIZE;
for (i = 0; i < this_arm; i++) {
if (arm_poll(ring, off)) {
fprintf(stderr, "arm failed at %d\n", off);
return 1;
}
off++;
}
ret = io_uring_submit(ring);
if (ret != this_arm) {
fprintf(stderr, "submitted %d, %d\n", ret, this_arm);
return 1;
}
to_arm -= this_arm;
}
return 0;
}
static int run(int cqe)
{
struct io_uring ring;
struct io_uring_params params = { };
pthread_t thread;
int i, j, ret;
for (i = 0; i < NFILES; i++) {
if (pipe(p[i].fd) < 0) {
perror("pipe");
return 1;
}
fcntl(p[i].fd[0], F_SETFL, O_NONBLOCK);
}
params.flags = IORING_SETUP_CQSIZE;
params.cq_entries = cqe;
ret = io_uring_queue_init_params(RING_SIZE, &ring, ¶ms);
if (ret) {
if (ret == -EINVAL) {
fprintf(stdout, "No CQSIZE, trying without\n");
ret = io_uring_queue_init(RING_SIZE, &ring, 0);
if (ret) {
fprintf(stderr, "ring setup failed: %d\n", ret);
return 1;
}
}
}
if (arm_polls(&ring))
goto err;
for (i = 0; i < NLOOPS; i++) {
pthread_create(&thread, NULL, trigger_polls_fn, NULL);
ret = reap_polls(&ring);
if (ret)
goto err;
pthread_join(thread, NULL);
for (j = 0; j < NFILES; j++)
p[j].triggered = 0;
}
io_uring_queue_exit(&ring);
for (i = 0; i < NFILES; i++) {
close(p[i].fd[0]);
close(p[i].fd[1]);
}
return 0;
err:
io_uring_queue_exit(&ring);
return 1;
}
int main(int argc, char *argv[])
{
struct rlimit rlim;
int ret;
if (argc > 1)
return 0;
ret = has_poll_update();
if (ret < 0) {
fprintf(stderr, "poll update check failed %i\n", ret);
return -1;
} else if (!ret) {
fprintf(stderr, "no poll update, skip\n");
return 0;
}
if (getrlimit(RLIMIT_NOFILE, &rlim) < 0) {
perror("getrlimit");
goto err;
}
if (rlim.rlim_cur < (2 * NFILES + 5)) {
rlim.rlim_cur = (2 * NFILES + 5);
rlim.rlim_max = rlim.rlim_cur;
if (setrlimit(RLIMIT_NOFILE, &rlim) < 0) {
if (errno == EPERM)
goto err_nofail;
perror("setrlimit");
goto err;
}
}
ret = run(1024);
if (ret) {
fprintf(stderr, "run(1024) failed\n");
goto err;
}
ret = run(8192);
if (ret) {
fprintf(stderr, "run(8192) failed\n");
goto err;
}
return 0;
err:
fprintf(stderr, "poll-many failed\n");
return 1;
err_nofail:
fprintf(stderr, "poll-many: not enough files available (and not root), "
"skipped\n");
return 0;
}
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