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/* SPDX-License-Identifier: MIT */
/*
* Description: basic fadvise test
*/
#include <errno.h>
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <fcntl.h>
#include <sys/types.h>
#include <sys/time.h>
#include "helpers.h"
#include "liburing.h"
#define FILE_SIZE (128 * 1024)
#define LOOPS 100
#define MIN_LOOPS 10
static unsigned long long utime_since(const struct timeval *s,
const struct timeval *e)
{
long long sec, usec;
sec = e->tv_sec - s->tv_sec;
usec = (e->tv_usec - s->tv_usec);
if (sec > 0 && usec < 0) {
sec--;
usec += 1000000;
}
sec *= 1000000;
return sec + usec;
}
static unsigned long long utime_since_now(struct timeval *tv)
{
struct timeval end;
gettimeofday(&end, NULL);
return utime_since(tv, &end);
}
static int do_fadvise(struct io_uring *ring, int fd, off_t offset, off_t len,
int advice)
{
struct io_uring_sqe *sqe;
struct io_uring_cqe *cqe;
int ret;
sqe = io_uring_get_sqe(ring);
if (!sqe) {
fprintf(stderr, "failed to get sqe\n");
return 1;
}
io_uring_prep_fadvise(sqe, fd, offset, len, advice);
sqe->user_data = advice;
ret = io_uring_submit_and_wait(ring, 1);
if (ret != 1) {
fprintf(stderr, "submit: %d\n", ret);
return 1;
}
ret = io_uring_wait_cqe(ring, &cqe);
if (ret) {
fprintf(stderr, "wait: %d\n", ret);
return 1;
}
ret = cqe->res;
if (ret == -EINVAL || ret == -EBADF) {
fprintf(stdout, "Fadvise not supported, skipping\n");
unlink(".fadvise.tmp");
exit(0);
} else if (ret) {
fprintf(stderr, "cqe->res=%d\n", cqe->res);
}
io_uring_cqe_seen(ring, cqe);
return ret;
}
static long do_read(int fd, char *buf)
{
struct timeval tv;
int ret;
long t;
ret = lseek(fd, 0, SEEK_SET);
if (ret) {
perror("lseek");
return -1;
}
gettimeofday(&tv, NULL);
ret = read(fd, buf, FILE_SIZE);
t = utime_since_now(&tv);
if (ret < 0) {
perror("read");
return -1;
} else if (ret != FILE_SIZE) {
fprintf(stderr, "short read1: %d\n", ret);
return -1;
}
return t;
}
static int test_fadvise(struct io_uring *ring, const char *filename)
{
unsigned long cached_read, uncached_read, cached_read2;
int fd, ret;
char *buf;
fd = open(filename, O_RDONLY);
if (fd < 0) {
perror("open");
return 1;
}
buf = t_malloc(FILE_SIZE);
cached_read = do_read(fd, buf);
if (cached_read == -1)
return 1;
ret = do_fadvise(ring, fd, 0, FILE_SIZE, POSIX_FADV_DONTNEED);
if (ret)
return 1;
uncached_read = do_read(fd, buf);
if (uncached_read == -1)
return 1;
ret = do_fadvise(ring, fd, 0, FILE_SIZE, POSIX_FADV_DONTNEED);
if (ret)
return 1;
ret = do_fadvise(ring, fd, 0, FILE_SIZE, POSIX_FADV_WILLNEED);
if (ret)
return 1;
fsync(fd);
cached_read2 = do_read(fd, buf);
if (cached_read2 == -1)
return 1;
if (cached_read < uncached_read &&
cached_read2 < uncached_read)
return 0;
return 2;
}
int main(int argc, char *argv[])
{
struct io_uring ring;
int ret, i, good, bad;
char *fname;
if (argc > 1) {
fname = argv[1];
} else {
fname = ".fadvise.tmp";
t_create_file(fname, FILE_SIZE);
}
if (io_uring_queue_init(8, &ring, 0)) {
fprintf(stderr, "ring creation failed\n");
goto err;
}
good = bad = 0;
for (i = 0; i < LOOPS; i++) {
ret = test_fadvise(&ring, fname);
if (ret == 1) {
fprintf(stderr, "read_fadvise failed\n");
goto err;
} else if (!ret)
good++;
else if (ret == 2)
bad++;
if (i >= MIN_LOOPS && !bad)
break;
}
/* too hard to reliably test, just ignore */
if (0 && bad > good) {
fprintf(stderr, "Suspicious timings\n");
goto err;
}
if (fname != argv[1])
unlink(fname);
io_uring_queue_exit(&ring);
return 0;
err:
if (fname != argv[1])
unlink(fname);
return 1;
}
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