-/*
- * gcc -D_GNU_SOURCE -Wall -O2 -o aio-ring aio-ring.c -lpthread -laio
- */
-#include <stdio.h>
-#include <errno.h>
-#include <assert.h>
-#include <stdlib.h>
-#include <stddef.h>
-#include <signal.h>
-#include <inttypes.h>
-
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <sys/ioctl.h>
-#include <sys/syscall.h>
-#include <sys/resource.h>
-#include <sys/mman.h>
-#include <linux/fs.h>
-#include <fcntl.h>
-#include <unistd.h>
-#include <libaio.h>
-#include <string.h>
-#include <pthread.h>
-#include <sched.h>
-
-#include "../arch/arch.h"
-
-#define IOCTX_FLAG_SCQRING (1 << 0) /* Use SQ/CQ rings */
-#define IOCTX_FLAG_IOPOLL (1 << 1)
-#define IOCTX_FLAG_FIXEDBUFS (1 << 2)
-#define IOCTX_FLAG_SQTHREAD (1 << 3) /* Use SQ thread */
-#define IOCTX_FLAG_SQWQ (1 << 4) /* Use SQ wq */
-#define IOCTX_FLAG_SQPOLL (1 << 5)
-
-#define IOEV_RES2_CACHEHIT (1 << 0)
-
-#define barrier() __asm__ __volatile__("": : :"memory")
-
-#define min(a, b) ((a < b) ? (a) : (b))
-
-typedef uint64_t u64;
-typedef uint32_t u32;
-typedef uint16_t u16;
-
-#define IORING_OFF_SQ_RING 0ULL
-#define IORING_OFF_CQ_RING 0x8000000ULL
-#define IORING_OFF_IOCB 0x10000000ULL
-
-struct aio_sqring_offsets {
- u32 head;
- u32 tail;
- u32 ring_mask;
- u32 ring_entries;
- u32 flags;
- u32 dropped;
- u32 array;
- u32 resv[3];
-};
-
-struct aio_cqring_offsets {
- u32 head;
- u32 tail;
- u32 ring_mask;
- u32 ring_entries;
- u32 overflow;
- u32 events;
- u32 resv[4];
-};
-
-struct aio_uring_params {
- u32 sq_entries;
- u32 cq_entries;
- u32 flags;
- u16 sq_thread_cpu;
- u16 resv[9];
- struct aio_sqring_offsets sq_off;
- struct aio_cqring_offsets cq_off;
-};
-
-struct aio_sq_ring {
- u32 *head;
- u32 *tail;
- u32 *ring_mask;
- u32 *ring_entries;
- u32 *array;
-};
-
-struct aio_cq_ring {
- u32 *head;
- u32 *tail;
- u32 *ring_mask;
- u32 *ring_entries;
- struct io_event *events;
-};
-
-#define IORING_ENTER_GETEVENTS (1 << 0)
-
-#define DEPTH 32
-
-#define BATCH_SUBMIT 8
-#define BATCH_COMPLETE 8
-
-#define BS 4096
-
-static unsigned sq_ring_mask, cq_ring_mask;
-
-struct submitter {
- pthread_t thread;
- unsigned long max_blocks;
- int ring_fd;
- struct drand48_data rand;
- struct aio_sq_ring sq_ring;
- struct iocb *iocbs;
- struct iovec iovecs[DEPTH];
- struct aio_cq_ring cq_ring;
- int inflight;
- unsigned long reaps;
- unsigned long done;
- unsigned long calls;
- unsigned long cachehit, cachemiss;
- volatile int finish;
- char filename[128];
-};
-
-static struct submitter submitters[1];
-static volatile int finish;
-
-static int polled = 0; /* use IO polling */
-static int fixedbufs = 0; /* use fixed user buffers */
-static int buffered = 1; /* use buffered IO, not O_DIRECT */
-static int sq_thread = 0; /* use kernel submission thread */
-static int sq_thread_cpu = 0; /* pin above thread to this CPU */
-
-static int io_uring_setup(unsigned entries, struct iovec *iovecs,
- struct aio_uring_params *p)
-{
- return syscall(__NR_sys_io_uring_setup, entries, iovecs, p);
-}
-
-static int io_uring_enter(struct submitter *s, unsigned int to_submit,
- unsigned int min_complete, unsigned int flags)
-{
- return syscall(__NR_sys_io_uring_enter, s->ring_fd, to_submit,
- min_complete, flags);
-}
-
-static int gettid(void)
-{
- return syscall(__NR_gettid);
-}
-
-static void init_io(struct submitter *s, int fd, unsigned index)
-{
- struct iocb *iocb = &s->iocbs[index];
- unsigned long offset;
- long r;
-
- lrand48_r(&s->rand, &r);
- offset = (r % (s->max_blocks - 1)) * BS;
-
- iocb->aio_fildes = fd;
- iocb->aio_lio_opcode = IO_CMD_PREAD;
- iocb->u.c.buf = s->iovecs[index].iov_base;
- iocb->u.c.nbytes = BS;
- iocb->u.c.offset = offset;
-}
-
-static int prep_more_ios(struct submitter *s, int fd, int max_ios)
-{
- struct aio_sq_ring *ring = &s->sq_ring;
- u32 index, tail, next_tail, prepped = 0;
-
- next_tail = tail = *ring->tail;
- do {
- next_tail++;
- barrier();
- if (next_tail == *ring->head)
- break;
-
- index = tail & sq_ring_mask;
- init_io(s, fd, index);
- ring->array[index] = index;
- prepped++;
- tail = next_tail;
- } while (prepped < max_ios);
-
- if (*ring->tail != tail) {
- /* order tail store with writes to iocbs above */
- barrier();
- *ring->tail = tail;
- barrier();
- }
- return prepped;
-}
-
-static int get_file_size(int fd, unsigned long *blocks)
-{
- struct stat st;
-
- if (fstat(fd, &st) < 0)
- return -1;
- if (S_ISBLK(st.st_mode)) {
- unsigned long long bytes;
-
- if (ioctl(fd, BLKGETSIZE64, &bytes) != 0)
- return -1;
-
- *blocks = bytes / BS;
- return 0;
- } else if (S_ISREG(st.st_mode)) {
- *blocks = st.st_size / BS;
- return 0;
- }
-
- return -1;
-}
-
-static int reap_events(struct submitter *s)
-{
- struct aio_cq_ring *ring = &s->cq_ring;
- struct io_event *ev;
- u32 head, reaped = 0;
-
- head = *ring->head;
- do {
- barrier();
- if (head == *ring->tail)
- break;
- ev = &ring->events[head & cq_ring_mask];
- if (ev->res != BS) {
- struct iocb *iocb = ev->obj;
-
- printf("io: unexpected ret=%ld\n", ev->res);
- printf("offset=%lu, size=%lu\n",
- (unsigned long) iocb->u.c.offset,
- (unsigned long) iocb->u.c.nbytes);
- return -1;
- }
- if (ev->res2 & IOEV_RES2_CACHEHIT)
- s->cachehit++;
- else
- s->cachemiss++;
- reaped++;
- head++;
- } while (1);
-
- s->inflight -= reaped;
- *ring->head = head;
- barrier();
- return reaped;
-}
-
-static void *submitter_fn(void *data)
-{
- struct submitter *s = data;
- int fd, ret, prepped, flags;
-
- printf("submitter=%d\n", gettid());
-
- flags = O_RDONLY;
- if (!buffered)
- flags |= O_DIRECT;
- fd = open(s->filename, flags);
- if (fd < 0) {
- perror("open");
- goto done;
- }
-
- if (get_file_size(fd, &s->max_blocks)) {
- printf("failed getting size of device/file\n");
- goto err;
- }
- if (s->max_blocks <= 1) {
- printf("Zero file/device size?\n");
- goto err;
- }
- s->max_blocks--;
-
- srand48_r(pthread_self(), &s->rand);
-
- prepped = 0;
- do {
- int to_wait, to_submit, this_reap, to_prep;
-
- if (!prepped && s->inflight < DEPTH) {
- to_prep = min(DEPTH - s->inflight, BATCH_SUBMIT);
- prepped = prep_more_ios(s, fd, to_prep);
- }
- s->inflight += prepped;
-submit_more:
- to_submit = prepped;
-submit:
- if (s->inflight + BATCH_SUBMIT < DEPTH)
- to_wait = 0;
- else
- to_wait = min(s->inflight + to_submit, BATCH_COMPLETE);
-
- ret = io_uring_enter(s, to_submit, to_wait,
- IORING_ENTER_GETEVENTS);
- s->calls++;
-
- this_reap = reap_events(s);
- if (this_reap == -1)
- break;
- s->reaps += this_reap;
-
- if (ret >= 0) {
- if (!ret) {
- to_submit = 0;
- if (s->inflight)
- goto submit;
- continue;
- } else if (ret < to_submit) {
- int diff = to_submit - ret;
-
- s->done += ret;
- prepped -= diff;
- goto submit_more;
- }
- s->done += ret;
- prepped = 0;
- continue;
- } else if (ret < 0) {
- if (errno == EAGAIN) {
- if (s->finish)
- break;
- if (this_reap)
- goto submit;
- to_submit = 0;
- goto submit;
- }
- printf("io_submit: %s\n", strerror(errno));
- break;
- }
- } while (!s->finish);
-err:
- close(fd);
-done:
- finish = 1;
- return NULL;
-}
-
-static void sig_int(int sig)
-{
- printf("Exiting on signal %d\n", sig);
- submitters[0].finish = 1;
- finish = 1;
-}
-
-static void arm_sig_int(void)
-{
- struct sigaction act;
-
- memset(&act, 0, sizeof(act));
- act.sa_handler = sig_int;
- act.sa_flags = SA_RESTART;
- sigaction(SIGINT, &act, NULL);
-}
-
-static int setup_ring(struct submitter *s)
-{
- struct aio_sq_ring *sring = &s->sq_ring;
- struct aio_cq_ring *cring = &s->cq_ring;
- struct aio_uring_params p;
- void *ptr;
- int fd;
-
- memset(&p, 0, sizeof(p));
-
- p.flags = IOCTX_FLAG_SCQRING;
- if (polled)
- p.flags |= IOCTX_FLAG_IOPOLL;
- if (fixedbufs)
- p.flags |= IOCTX_FLAG_FIXEDBUFS;
- if (buffered)
- p.flags |= IOCTX_FLAG_SQWQ;
- else if (sq_thread) {
- p.flags |= IOCTX_FLAG_SQTHREAD;
- p.sq_thread_cpu = sq_thread_cpu;
- }
-
- if (fixedbufs)
- fd = io_uring_setup(DEPTH, s->iovecs, &p);
- else
- fd = io_uring_setup(DEPTH, NULL, &p);
- if (fd < 0) {
- perror("io_uring_setup");
- return 1;
- }
-
- s->ring_fd = fd;
- ptr = mmap(0, p.sq_off.array + p.sq_entries * sizeof(u32),
- PROT_READ | PROT_WRITE, MAP_SHARED | MAP_POPULATE, fd,
- IORING_OFF_SQ_RING);
- printf("sq_ring ptr = 0x%p\n", ptr);
- sring->head = ptr + p.sq_off.head;
- sring->tail = ptr + p.sq_off.tail;
- sring->ring_mask = ptr + p.sq_off.ring_mask;
- sring->ring_entries = ptr + p.sq_off.ring_entries;
- sring->array = ptr + p.sq_off.array;
- sq_ring_mask = *sring->ring_mask;
-
- s->iocbs = mmap(0, p.sq_entries * sizeof(struct iocb),
- PROT_READ | PROT_WRITE, MAP_SHARED | MAP_POPULATE, fd,
- IORING_OFF_IOCB);
- printf("iocbs ptr = 0x%p\n", s->iocbs);
-
- ptr = mmap(0, p.cq_off.events + p.cq_entries * sizeof(struct io_event),
- PROT_READ | PROT_WRITE, MAP_SHARED | MAP_POPULATE, fd,
- IORING_OFF_CQ_RING);
- printf("cq_ring ptr = 0x%p\n", ptr);
- cring->head = ptr + p.cq_off.head;
- cring->tail = ptr + p.cq_off.tail;
- cring->ring_mask = ptr + p.cq_off.ring_mask;
- cring->ring_entries = ptr + p.cq_off.ring_entries;
- cring->events = ptr + p.cq_off.events;
- cq_ring_mask = *cring->ring_mask;
- return 0;
-}
-
-int main(int argc, char *argv[])
-{
- struct submitter *s = &submitters[0];
- unsigned long done, calls, reap, cache_hit, cache_miss;
- int err, i;
- struct rlimit rlim;
- void *ret;
-
- if (argc < 2) {
- printf("%s: filename\n", argv[0]);
- return 1;
- }
-
- rlim.rlim_cur = RLIM_INFINITY;
- rlim.rlim_max = RLIM_INFINITY;
- if (setrlimit(RLIMIT_MEMLOCK, &rlim) < 0) {
- perror("setrlimit");
- return 1;
- }
-
- arm_sig_int();
-
- for (i = 0; i < DEPTH; i++) {
- void *buf;
-
- if (posix_memalign(&buf, BS, BS)) {
- printf("failed alloc\n");
- return 1;
- }
- s->iovecs[i].iov_base = buf;
- s->iovecs[i].iov_len = BS;
- }
-
- err = setup_ring(s);
- if (err) {
- printf("ring setup failed: %s, %d\n", strerror(errno), err);
- return 1;
- }
- printf("polled=%d, fixedbufs=%d, buffered=%d", polled, fixedbufs, buffered);
- printf(" QD=%d, sq_ring=%d, cq_ring=%d\n", DEPTH, *s->sq_ring.ring_entries, *s->cq_ring.ring_entries);
- strcpy(s->filename, argv[1]);
-
- pthread_create(&s->thread, NULL, submitter_fn, s);
-
- cache_hit = cache_miss = reap = calls = done = 0;
- do {
- unsigned long this_done = 0;
- unsigned long this_reap = 0;
- unsigned long this_call = 0;
- unsigned long this_cache_hit = 0;
- unsigned long this_cache_miss = 0;
- unsigned long rpc = 0, ipc = 0;
- double hit = 0.0;
-
- sleep(1);
- this_done += s->done;
- this_call += s->calls;
- this_reap += s->reaps;
- this_cache_hit += s->cachehit;
- this_cache_miss += s->cachemiss;
- if (this_cache_hit && this_cache_miss) {
- unsigned long hits, total;
-
- hits = this_cache_hit - cache_hit;
- total = hits + this_cache_miss - cache_miss;
- hit = (double) hits / (double) total;
- hit *= 100.0;
- }
- if (this_call - calls) {
- rpc = (this_done - done) / (this_call - calls);
- ipc = (this_reap - reap) / (this_call - calls);
- }
- printf("IOPS=%lu, IOS/call=%lu/%lu, inflight=%u (head=%u tail=%u), Cachehit=%0.2f%%\n",
- this_done - done, rpc, ipc, s->inflight,
- *s->cq_ring.head, *s->cq_ring.tail, hit);
- done = this_done;
- calls = this_call;
- reap = this_reap;
- cache_hit = s->cachehit;
- cache_miss = s->cachemiss;
- } while (!finish);
-
- pthread_join(s->thread, &ret);
- return 0;
-}
projects / fio.git / commitdiff