[fio.git] / t / io_uring.c

#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 <sys/uio.h>
#include <linux/fs.h>
#include <fcntl.h>
#include <unistd.h>
#include <string.h>
#include <pthread.h>
#include <sched.h>

#include "../arch/arch.h"
#include "../lib/types.h"
#include "../os/linux/io_uring.h"

#define barrier()	__asm__ __volatile__("": : :"memory")

#define min(a, b)		((a < b) ? (a) : (b))

struct io_sq_ring {
	unsigned *head;
	unsigned *tail;
	unsigned *ring_mask;
	unsigned *ring_entries;
	unsigned *flags;
	unsigned *array;
};

struct io_cq_ring {
	unsigned *head;
	unsigned *tail;
	unsigned *ring_mask;
	unsigned *ring_entries;
	struct io_uring_cqe *cqes;
};

#define DEPTH			128

#define BATCH_SUBMIT		64
#define BATCH_COMPLETE		64

#define BS			4096

#define MAX_FDS			16

static unsigned sq_ring_mask, cq_ring_mask;

struct file {
	unsigned long max_blocks;
	unsigned pending_ios;
	int real_fd;
	int fixed_fd;
};

struct submitter {
	pthread_t thread;
	int ring_fd;
	struct drand48_data rand;
	struct io_sq_ring sq_ring;
	struct io_uring_sqe *sqes;
	struct iovec iovecs[DEPTH];
	struct io_cq_ring cq_ring;
	int inflight;
	unsigned long reaps;
	unsigned long done;
	unsigned long calls;
	unsigned long cachehit, cachemiss;
	volatile int finish;

	__s32 *fds;

	struct file files[MAX_FDS];
	unsigned nr_files;
	unsigned cur_file;
};

static struct submitter submitters[1];
static volatile int finish;

static int polled = 1;		/* use IO polling */
static int fixedbufs = 1;	/* use fixed user buffers */
static int register_files = 1;	/* use fixed files */
static int buffered = 0;	/* use buffered IO, not O_DIRECT */
static int sq_thread_poll = 0;	/* use kernel submission/poller thread */
static int sq_thread_cpu = -1;	/* pin above thread to this CPU */
static int do_nop = 0;		/* no-op SQ ring commands */

static int io_uring_register_buffers(struct submitter *s)
{
	struct io_uring_register_buffers reg = {
		.iovecs = s->iovecs,
		.nr_iovecs = DEPTH
	};

	if (do_nop)
		return 0;

	return syscall(__NR_sys_io_uring_register, s->ring_fd,
			IORING_REGISTER_BUFFERS, &reg);
}

static int io_uring_register_files(struct submitter *s)
{
	struct io_uring_register_files reg;
	int i;

	if (do_nop)
		return 0;

	s->fds = calloc(s->nr_files, sizeof(__s32));
	for (i = 0; i < s->nr_files; i++) {
		s->fds[i] = s->files[i].real_fd;
		s->files[i].fixed_fd = i;
	}
	reg.fds = s->fds;
	reg.nr_fds = s->nr_files;

	return syscall(__NR_sys_io_uring_register, s->ring_fd,
			IORING_REGISTER_FILES, &reg);
}

static int io_uring_setup(unsigned entries, struct io_uring_params *p)
{
	return syscall(__NR_sys_io_uring_setup, entries, 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 unsigned file_depth(struct submitter *s)
{
	return (DEPTH + s->nr_files - 1) / s->nr_files;
}

static void init_io(struct submitter *s, unsigned index)
{
	struct io_uring_sqe *sqe = &s->sqes[index];
	unsigned long offset;
	struct file *f;
	long r;

	if (do_nop) {
		sqe->opcode = IORING_OP_NOP;
		return;
	}

	if (s->nr_files == 1) {
		f = &s->files[0];
	} else {
		f = &s->files[s->cur_file];
		if (f->pending_ios >= file_depth(s)) {
			s->cur_file++;
			if (s->cur_file == s->nr_files)
				s->cur_file = 0;
		}
	}
	f->pending_ios++;

	lrand48_r(&s->rand, &r);
	offset = (r % (f->max_blocks - 1)) * BS;

	if (register_files) {
		sqe->flags = IOSQE_FIXED_FILE;
		sqe->fd = f->fixed_fd;
	} else {
		sqe->flags = 0;
		sqe->fd = f->real_fd;
	}
	if (fixedbufs) {
		sqe->opcode = IORING_OP_READ_FIXED;
		sqe->addr = s->iovecs[index].iov_base;
		sqe->len = BS;
		sqe->buf_index = index;
	} else {
		sqe->opcode = IORING_OP_READV;
		sqe->addr = &s->iovecs[index];
		sqe->len = 1;
		sqe->buf_index = 0;
	}
	sqe->ioprio = 0;
	sqe->off = offset;
	sqe->user_data = (unsigned long) f;
}

static int prep_more_ios(struct submitter *s, int max_ios)
{
	struct io_sq_ring *ring = &s->sq_ring;
	unsigned 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, index);
		ring->array[index] = index;
		prepped++;
		tail = next_tail;
	} while (prepped < max_ios);

	if (*ring->tail != tail) {
		/* order tail store with writes to sqes above */
		barrier();
		*ring->tail = tail;
		barrier();
	}
	return prepped;
}

static int get_file_size(struct file *f)
{
	struct stat st;

	if (fstat(f->real_fd, &st) < 0)
		return -1;
	if (S_ISBLK(st.st_mode)) {
		unsigned long long bytes;

		if (ioctl(f->real_fd, BLKGETSIZE64, &bytes) != 0)
			return -1;

		f->max_blocks = bytes / BS;
		return 0;
	} else if (S_ISREG(st.st_mode)) {
		f->max_blocks = st.st_size / BS;
		return 0;
	}

	return -1;
}

static int reap_events(struct submitter *s)
{
	struct io_cq_ring *ring = &s->cq_ring;
	struct io_uring_cqe *cqe;
	unsigned head, reaped = 0;

	head = *ring->head;
	do {
		struct file *f;

		barrier();
		if (head == *ring->tail)
			break;
		cqe = &ring->cqes[head & cq_ring_mask];
		if (!do_nop) {
			f = (struct file *) (uintptr_t) cqe->user_data;
			f->pending_ios--;
			if (cqe->res != BS) {
				printf("io: unexpected ret=%d\n", cqe->res);
				return -1;
			}
		}
		if (cqe->flags & IOCQE_FLAG_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;
	struct io_sq_ring *ring = &s->sq_ring;
	int ret, prepped;

	printf("submitter=%d\n", gettid());

	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, to_prep);
		}
		s->inflight += prepped;
submit_more:
		to_submit = prepped;
submit:
		if (to_submit && (s->inflight + to_submit < DEPTH))
			to_wait = 0;
		else
			to_wait = min(s->inflight + to_submit, BATCH_COMPLETE);

		/*
		 * Only need to call io_uring_enter if we're not using SQ thread
		 * poll, or if IORING_SQ_NEED_WAKEUP is set.
		 */
		if (!sq_thread_poll || (*ring->flags & IORING_SQ_NEED_WAKEUP)) {
			unsigned flags = 0;

			if (to_wait)
				flags = IORING_ENTER_GETEVENTS;
			ret = io_uring_enter(s, to_submit, to_wait, flags);
			s->calls++;
		}

		/*
		 * For non SQ thread poll, we already got the events we needed
		 * through the io_uring_enter() above. For SQ thread poll, we
		 * need to loop here until we find enough events.
		 */
		this_reap = 0;
		do {
			int r;
			r = reap_events(s);
			if (r == -1)
				break;
			else if (r > 0)
				this_reap += r;
		} while (sq_thread_poll && this_reap < to_wait);
		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);

	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 io_sq_ring *sring = &s->sq_ring;
	struct io_cq_ring *cring = &s->cq_ring;
	struct io_uring_params p;
	int ret, fd;
	void *ptr;

	memset(&p, 0, sizeof(p));

	if (polled)
		p.flags |= IORING_SETUP_IOPOLL;
	if (sq_thread_poll) {
		p.flags |= IORING_SETUP_SQPOLL;
		if (sq_thread_cpu != -1) {
			p.flags |= IORING_SETUP_SQ_AFF;
			p.sq_thread_cpu = sq_thread_cpu;
		}
	}

	fd = io_uring_setup(DEPTH, &p);
	if (fd < 0) {
		perror("io_uring_setup");
		return 1;
	}
	s->ring_fd = fd;

	if (fixedbufs) {
		ret = io_uring_register_buffers(s);
		if (ret < 0) {
			perror("io_uring_register_buffers");
			return 1;
		}
	}

	if (register_files) {
		ret = io_uring_register_files(s);
		if (ret < 0) {
			perror("io_uring_register_files");
			return 1;
		}
	}

	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->flags = ptr + p.sq_off.flags;
	sring->array = ptr + p.sq_off.array;
	sq_ring_mask = *sring->ring_mask;

	s->sqes = mmap(0, p.sq_entries * sizeof(struct io_uring_sqe),
			PROT_READ | PROT_WRITE, MAP_SHARED | MAP_POPULATE, fd,
			IORING_OFF_SQES);
	printf("sqes ptr    = 0x%p\n", s->sqes);

	ptr = mmap(0, p.cq_off.cqes + p.cq_entries * sizeof(struct io_uring_cqe),
			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->cqes = ptr + p.cq_off.cqes;
	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, flags, fd;
	void *ret;

	if (!do_nop && argc < 2) {
		printf("%s: filename\n", argv[0]);
		return 1;
	}

	flags = O_RDONLY | O_NOATIME;
	if (!buffered)
		flags |= O_DIRECT;

	i = 1;
	while (!do_nop && i < argc) {
		struct file *f = &s->files[s->nr_files];

		fd = open(argv[i], flags);
		if (fd < 0) {
			perror("open");
			return 1;
		}
		f->real_fd = fd;
		if (get_file_size(f)) {
			printf("failed getting size of device/file\n");
			return 1;
		}
		if (f->max_blocks <= 1) {
			printf("Zero file/device size?\n");
			return 1;
		}
		f->max_blocks--;

		printf("Added file %s\n", argv[i]);
		s->nr_files++;
		i++;
	}

	if (fixedbufs) {
		struct rlimit rlim;

		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);

	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);
		} else
			rpc = ipc = -1;
		printf("IOPS=%lu, IOS/call=%ld/%ld, 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);
	close(s->ring_fd);
	return 0;
}
Commit	Line	Data
	1	#include <stdio.h>
	2	#include <errno.h>
	3	#include <assert.h>
	4	#include <stdlib.h>
	5	#include <stddef.h>
	6	#include <signal.h>
	7	#include <inttypes.h>
	8
	9	#include <sys/types.h>
	10	#include <sys/stat.h>
	11	#include <sys/ioctl.h>
	12	#include <sys/syscall.h>
	13	#include <sys/resource.h>
	14	#include <sys/mman.h>
	15	#include <sys/uio.h>
	16	#include <linux/fs.h>
	17	#include <fcntl.h>
	18	#include <unistd.h>
	19	#include <string.h>
	20	#include <pthread.h>
	21	#include <sched.h>
	22
	23	#include "../arch/arch.h"
	24	#include "../lib/types.h"
	25	#include "../os/linux/io_uring.h"
	26
	27	#define barrier() __asm__ __volatile__("": : :"memory")
	28
	29	#define min(a, b) ((a < b) ? (a) : (b))
	30
	31	struct io_sq_ring {
	32	unsigned *head;
	33	unsigned *tail;
	34	unsigned *ring_mask;
	35	unsigned *ring_entries;
	36	unsigned *flags;
	37	unsigned *array;
	38	};
	39
	40	struct io_cq_ring {
	41	unsigned *head;
	42	unsigned *tail;
	43	unsigned *ring_mask;
	44	unsigned *ring_entries;
	45	struct io_uring_cqe *cqes;
	46	};
	47
	48	#define DEPTH 128
	49
	50	#define BATCH_SUBMIT 64
	51	#define BATCH_COMPLETE 64
	52
	53	#define BS 4096
	54
	55	#define MAX_FDS 16
	56
	57	static unsigned sq_ring_mask, cq_ring_mask;
	58
	59	struct file {
	60	unsigned long max_blocks;
	61	unsigned pending_ios;
	62	int real_fd;
	63	int fixed_fd;
	64	};
	65
	66	struct submitter {
	67	pthread_t thread;
	68	int ring_fd;
	69	struct drand48_data rand;
	70	struct io_sq_ring sq_ring;
	71	struct io_uring_sqe *sqes;
	72	struct iovec iovecs[DEPTH];
	73	struct io_cq_ring cq_ring;
	74	int inflight;
	75	unsigned long reaps;
	76	unsigned long done;
	77	unsigned long calls;
	78	unsigned long cachehit, cachemiss;
	79	volatile int finish;
	80
	81	__s32 *fds;
	82
	83	struct file files[MAX_FDS];
	84	unsigned nr_files;
	85	unsigned cur_file;
	86	};
	87
	88	static struct submitter submitters[1];
	89	static volatile int finish;
	90
	91	static int polled = 1; /* use IO polling */
	92	static int fixedbufs = 1; /* use fixed user buffers */
	93	static int register_files = 1; /* use fixed files */
	94	static int buffered = 0; /* use buffered IO, not O_DIRECT */
	95	static int sq_thread_poll = 0; /* use kernel submission/poller thread */
	96	static int sq_thread_cpu = -1; /* pin above thread to this CPU */
	97	static int do_nop = 0; /* no-op SQ ring commands */
	98
	99	static int io_uring_register_buffers(struct submitter *s)
	100	{
	101	struct io_uring_register_buffers reg = {
	102	.iovecs = s->iovecs,
	103	.nr_iovecs = DEPTH
	104	};
	105
	106	if (do_nop)
	107	return 0;
	108
	109	return syscall(__NR_sys_io_uring_register, s->ring_fd,
	110	IORING_REGISTER_BUFFERS, &reg);
	111	}
	112
	113	static int io_uring_register_files(struct submitter *s)
	114	{
	115	struct io_uring_register_files reg;
	116	int i;
	117
	118	if (do_nop)
	119	return 0;
	120
	121	s->fds = calloc(s->nr_files, sizeof(__s32));
	122	for (i = 0; i < s->nr_files; i++) {
	123	s->fds[i] = s->files[i].real_fd;
	124	s->files[i].fixed_fd = i;
	125	}
	126	reg.fds = s->fds;
	127	reg.nr_fds = s->nr_files;
	128
	129	return syscall(__NR_sys_io_uring_register, s->ring_fd,
	130	IORING_REGISTER_FILES, &reg);
	131	}
	132
	133	static int io_uring_setup(unsigned entries, struct io_uring_params *p)
	134	{
	135	return syscall(__NR_sys_io_uring_setup, entries, p);
	136	}
	137
	138	static int io_uring_enter(struct submitter *s, unsigned int to_submit,
	139	unsigned int min_complete, unsigned int flags)
	140	{
	141	return syscall(__NR_sys_io_uring_enter, s->ring_fd, to_submit,
	142	min_complete, flags);
	143	}
	144
	145	static int gettid(void)
	146	{
	147	return syscall(__NR_gettid);
	148	}
	149
	150	static unsigned file_depth(struct submitter *s)
	151	{
	152	return (DEPTH + s->nr_files - 1) / s->nr_files;
	153	}
	154
	155	static void init_io(struct submitter *s, unsigned index)
	156	{
	157	struct io_uring_sqe *sqe = &s->sqes[index];
	158	unsigned long offset;
	159	struct file *f;
	160	long r;
	161
	162	if (do_nop) {
	163	sqe->opcode = IORING_OP_NOP;
	164	return;
	165	}
	166
	167	if (s->nr_files == 1) {
	168	f = &s->files[0];
	169	} else {
	170	f = &s->files[s->cur_file];
	171	if (f->pending_ios >= file_depth(s)) {
	172	s->cur_file++;
	173	if (s->cur_file == s->nr_files)
	174	s->cur_file = 0;
	175	}
	176	}
	177	f->pending_ios++;
	178
	179	lrand48_r(&s->rand, &r);
	180	offset = (r % (f->max_blocks - 1)) * BS;
	181
	182	if (register_files) {
	183	sqe->flags = IOSQE_FIXED_FILE;
	184	sqe->fd = f->fixed_fd;
	185	} else {
	186	sqe->flags = 0;
	187	sqe->fd = f->real_fd;
	188	}
	189	if (fixedbufs) {
	190	sqe->opcode = IORING_OP_READ_FIXED;
	191	sqe->addr = s->iovecs[index].iov_base;
	192	sqe->len = BS;
	193	sqe->buf_index = index;
	194	} else {
	195	sqe->opcode = IORING_OP_READV;
	196	sqe->addr = &s->iovecs[index];
	197	sqe->len = 1;
	198	sqe->buf_index = 0;
	199	}
	200	sqe->ioprio = 0;
	201	sqe->off = offset;
	202	sqe->user_data = (unsigned long) f;
	203	}
	204
	205	static int prep_more_ios(struct submitter *s, int max_ios)
	206	{
	207	struct io_sq_ring *ring = &s->sq_ring;
	208	unsigned index, tail, next_tail, prepped = 0;
	209
	210	next_tail = tail = *ring->tail;
	211	do {
	212	next_tail++;
	213	barrier();
	214	if (next_tail == *ring->head)
	215	break;
	216
	217	index = tail & sq_ring_mask;
	218	init_io(s, index);
	219	ring->array[index] = index;
	220	prepped++;
	221	tail = next_tail;
	222	} while (prepped < max_ios);
	223
	224	if (*ring->tail != tail) {
	225	/* order tail store with writes to sqes above */
	226	barrier();
	227	*ring->tail = tail;
	228	barrier();
	229	}
	230	return prepped;
	231	}
	232
	233	static int get_file_size(struct file *f)
	234	{
	235	struct stat st;
	236
	237	if (fstat(f->real_fd, &st) < 0)
	238	return -1;
	239	if (S_ISBLK(st.st_mode)) {
	240	unsigned long long bytes;
	241
	242	if (ioctl(f->real_fd, BLKGETSIZE64, &bytes) != 0)
	243	return -1;
	244
	245	f->max_blocks = bytes / BS;
	246	return 0;
	247	} else if (S_ISREG(st.st_mode)) {
	248	f->max_blocks = st.st_size / BS;
	249	return 0;
	250	}
	251
	252	return -1;
	253	}
	254
	255	static int reap_events(struct submitter *s)
	256	{
	257	struct io_cq_ring *ring = &s->cq_ring;
	258	struct io_uring_cqe *cqe;
	259	unsigned head, reaped = 0;
	260
	261	head = *ring->head;
	262	do {
	263	struct file *f;
	264
	265	barrier();
	266	if (head == *ring->tail)
	267	break;
	268	cqe = &ring->cqes[head & cq_ring_mask];
	269	if (!do_nop) {
	270	f = (struct file *) (uintptr_t) cqe->user_data;
	271	f->pending_ios--;
	272	if (cqe->res != BS) {
	273	printf("io: unexpected ret=%d\n", cqe->res);
	274	return -1;
	275	}
	276	}
	277	if (cqe->flags & IOCQE_FLAG_CACHEHIT)
	278	s->cachehit++;
	279	else
	280	s->cachemiss++;
	281	reaped++;
	282	head++;
	283	} while (1);
	284
	285	s->inflight -= reaped;
	286	*ring->head = head;
	287	barrier();
	288	return reaped;
	289	}
	290
	291	static void submitter_fn(void data)
	292	{
	293	struct submitter *s = data;
	294	struct io_sq_ring *ring = &s->sq_ring;
	295	int ret, prepped;
	296
	297	printf("submitter=%d\n", gettid());
	298
	299	srand48_r(pthread_self(), &s->rand);
	300
	301	prepped = 0;
	302	do {
	303	int to_wait, to_submit, this_reap, to_prep;
	304
	305	if (!prepped && s->inflight < DEPTH) {
	306	to_prep = min(DEPTH - s->inflight, BATCH_SUBMIT);
	307	prepped = prep_more_ios(s, to_prep);
	308	}
	309	s->inflight += prepped;
	310	submit_more:
	311	to_submit = prepped;
	312	submit:
	313	if (to_submit && (s->inflight + to_submit < DEPTH))
	314	to_wait = 0;
	315	else
	316	to_wait = min(s->inflight + to_submit, BATCH_COMPLETE);
	317
	318	/*
	319	* Only need to call io_uring_enter if we're not using SQ thread
	320	* poll, or if IORING_SQ_NEED_WAKEUP is set.
	321	*/
	322	if (!sq_thread_poll \|\| (*ring->flags & IORING_SQ_NEED_WAKEUP)) {
	323	unsigned flags = 0;
	324
	325	if (to_wait)
	326	flags = IORING_ENTER_GETEVENTS;
	327	ret = io_uring_enter(s, to_submit, to_wait, flags);
	328	s->calls++;
	329	}
	330
	331	/*
	332	* For non SQ thread poll, we already got the events we needed
	333	* through the io_uring_enter() above. For SQ thread poll, we
	334	* need to loop here until we find enough events.
	335	*/
	336	this_reap = 0;
	337	do {
	338	int r;
	339	r = reap_events(s);
	340	if (r == -1)
	341	break;
	342	else if (r > 0)
	343	this_reap += r;
	344	} while (sq_thread_poll && this_reap < to_wait);
	345	s->reaps += this_reap;
	346
	347	if (ret >= 0) {
	348	if (!ret) {
	349	to_submit = 0;
	350	if (s->inflight)
	351	goto submit;
	352	continue;
	353	} else if (ret < to_submit) {
	354	int diff = to_submit - ret;
	355
	356	s->done += ret;
	357	prepped -= diff;
	358	goto submit_more;
	359	}
	360	s->done += ret;
	361	prepped = 0;
	362	continue;
	363	} else if (ret < 0) {
	364	if (errno == EAGAIN) {
	365	if (s->finish)
	366	break;
	367	if (this_reap)
	368	goto submit;
	369	to_submit = 0;
	370	goto submit;
	371	}
	372	printf("io_submit: %s\n", strerror(errno));
	373	break;
	374	}
	375	} while (!s->finish);
	376
	377	finish = 1;
	378	return NULL;
	379	}
	380
	381	static void sig_int(int sig)
	382	{
	383	printf("Exiting on signal %d\n", sig);
	384	submitters[0].finish = 1;
	385	finish = 1;
	386	}
	387
	388	static void arm_sig_int(void)
	389	{
	390	struct sigaction act;
	391
	392	memset(&act, 0, sizeof(act));
	393	act.sa_handler = sig_int;
	394	act.sa_flags = SA_RESTART;
	395	sigaction(SIGINT, &act, NULL);
	396	}
	397
	398	static int setup_ring(struct submitter *s)
	399	{
	400	struct io_sq_ring *sring = &s->sq_ring;
	401	struct io_cq_ring *cring = &s->cq_ring;
	402	struct io_uring_params p;
	403	int ret, fd;
	404	void *ptr;
	405
	406	memset(&p, 0, sizeof(p));
	407
	408	if (polled)
	409	p.flags \|= IORING_SETUP_IOPOLL;
	410	if (sq_thread_poll) {
	411	p.flags \|= IORING_SETUP_SQPOLL;
	412	if (sq_thread_cpu != -1) {
	413	p.flags \|= IORING_SETUP_SQ_AFF;
	414	p.sq_thread_cpu = sq_thread_cpu;
	415	}
	416	}
	417
	418	fd = io_uring_setup(DEPTH, &p);
	419	if (fd < 0) {
	420	perror("io_uring_setup");
	421	return 1;
	422	}
	423	s->ring_fd = fd;
	424
	425	if (fixedbufs) {
	426	ret = io_uring_register_buffers(s);
	427	if (ret < 0) {
	428	perror("io_uring_register_buffers");
	429	return 1;
	430	}
	431	}
	432
	433	if (register_files) {
	434	ret = io_uring_register_files(s);
	435	if (ret < 0) {
	436	perror("io_uring_register_files");
	437	return 1;
	438	}
	439	}
	440
	441	ptr = mmap(0, p.sq_off.array + p.sq_entries * sizeof(__u32),
	442	PROT_READ \| PROT_WRITE, MAP_SHARED \| MAP_POPULATE, fd,
	443	IORING_OFF_SQ_RING);
	444	printf("sq_ring ptr = 0x%p\n", ptr);
	445	sring->head = ptr + p.sq_off.head;
	446	sring->tail = ptr + p.sq_off.tail;
	447	sring->ring_mask = ptr + p.sq_off.ring_mask;
	448	sring->ring_entries = ptr + p.sq_off.ring_entries;
	449	sring->flags = ptr + p.sq_off.flags;
	450	sring->array = ptr + p.sq_off.array;
	451	sq_ring_mask = *sring->ring_mask;
	452
	453	s->sqes = mmap(0, p.sq_entries * sizeof(struct io_uring_sqe),
	454	PROT_READ \| PROT_WRITE, MAP_SHARED \| MAP_POPULATE, fd,
	455	IORING_OFF_SQES);
	456	printf("sqes ptr = 0x%p\n", s->sqes);
	457
	458	ptr = mmap(0, p.cq_off.cqes + p.cq_entries * sizeof(struct io_uring_cqe),
	459	PROT_READ \| PROT_WRITE, MAP_SHARED \| MAP_POPULATE, fd,
	460	IORING_OFF_CQ_RING);
	461	printf("cq_ring ptr = 0x%p\n", ptr);
	462	cring->head = ptr + p.cq_off.head;
	463	cring->tail = ptr + p.cq_off.tail;
	464	cring->ring_mask = ptr + p.cq_off.ring_mask;
	465	cring->ring_entries = ptr + p.cq_off.ring_entries;
	466	cring->cqes = ptr + p.cq_off.cqes;
	467	cq_ring_mask = *cring->ring_mask;
	468	return 0;
	469	}
	470
	471	int main(int argc, char *argv[])
	472	{
	473	struct submitter *s = &submitters[0];
	474	unsigned long done, calls, reap, cache_hit, cache_miss;
	475	int err, i, flags, fd;
	476	void *ret;
	477
	478	if (!do_nop && argc < 2) {
	479	printf("%s: filename\n", argv[0]);
	480	return 1;
	481	}
	482
	483	flags = O_RDONLY \| O_NOATIME;
	484	if (!buffered)
	485	flags \|= O_DIRECT;
	486
	487	i = 1;
	488	while (!do_nop && i < argc) {
	489	struct file *f = &s->files[s->nr_files];
	490
	491	fd = open(argv[i], flags);
	492	if (fd < 0) {
	493	perror("open");
	494	return 1;
	495	}
	496	f->real_fd = fd;
	497	if (get_file_size(f)) {
	498	printf("failed getting size of device/file\n");
	499	return 1;
	500	}
	501	if (f->max_blocks <= 1) {
	502	printf("Zero file/device size?\n");
	503	return 1;
	504	}
	505	f->max_blocks--;
	506
	507	printf("Added file %s\n", argv[i]);
	508	s->nr_files++;
	509	i++;
	510	}
	511
	512	if (fixedbufs) {
	513	struct rlimit rlim;
	514
	515	rlim.rlim_cur = RLIM_INFINITY;
	516	rlim.rlim_max = RLIM_INFINITY;
	517	if (setrlimit(RLIMIT_MEMLOCK, &rlim) < 0) {
	518	perror("setrlimit");
	519	return 1;
	520	}
	521	}
	522
	523	arm_sig_int();
	524
	525	for (i = 0; i < DEPTH; i++) {
	526	void *buf;
	527
	528	if (posix_memalign(&buf, BS, BS)) {
	529	printf("failed alloc\n");
	530	return 1;
	531	}
	532	s->iovecs[i].iov_base = buf;
	533	s->iovecs[i].iov_len = BS;
	534	}
	535
	536	err = setup_ring(s);
	537	if (err) {
	538	printf("ring setup failed: %s, %d\n", strerror(errno), err);
	539	return 1;
	540	}
	541	printf("polled=%d, fixedbufs=%d, buffered=%d", polled, fixedbufs, buffered);
	542	printf(" QD=%d, sq_ring=%d, cq_ring=%d\n", DEPTH, s->sq_ring.ring_entries, s->cq_ring.ring_entries);
	543
	544	pthread_create(&s->thread, NULL, submitter_fn, s);
	545
	546	cache_hit = cache_miss = reap = calls = done = 0;
	547	do {
	548	unsigned long this_done = 0;
	549	unsigned long this_reap = 0;
	550	unsigned long this_call = 0;
	551	unsigned long this_cache_hit = 0;
	552	unsigned long this_cache_miss = 0;
	553	unsigned long rpc = 0, ipc = 0;
	554	double hit = 0.0;
	555
	556	sleep(1);
	557	this_done += s->done;
	558	this_call += s->calls;
	559	this_reap += s->reaps;
	560	this_cache_hit += s->cachehit;
	561	this_cache_miss += s->cachemiss;
	562	if (this_cache_hit && this_cache_miss) {
	563	unsigned long hits, total;
	564
	565	hits = this_cache_hit - cache_hit;
	566	total = hits + this_cache_miss - cache_miss;
	567	hit = (double) hits / (double) total;
	568	hit *= 100.0;
	569	}
	570	if (this_call - calls) {
	571	rpc = (this_done - done) / (this_call - calls);
	572	ipc = (this_reap - reap) / (this_call - calls);
	573	} else
	574	rpc = ipc = -1;
	575	printf("IOPS=%lu, IOS/call=%ld/%ld, inflight=%u (head=%u tail=%u), Cachehit=%0.2f%%\n",
	576	this_done - done, rpc, ipc, s->inflight,
	577	s->cq_ring.head, s->cq_ring.tail, hit);
	578	done = this_done;
	579	calls = this_call;
	580	reap = this_reap;
	581	cache_hit = s->cachehit;
	582	cache_miss = s->cachemiss;
	583	} while (!finish);
	584
	585	pthread_join(s->thread, &ret);
	586	close(s->ring_fd);
	587	return 0;
	588	}