[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/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 *array;
};

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

#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 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;
	char filename[128];
};

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

static int polled = 1;		/* use IO polling */
static int fixedbufs = 0;	/* use fixed user buffers */
static int buffered = 0;	/* 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 io_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 io_uring_sqe *sqe = &s->sqes[index];
	unsigned long offset;
	long r;

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

	if (fixedbufs) {
		sqe->opcode = IORING_OP_READ_FIXED;
		sqe->addr = s->iovecs[index].iov_base;
		sqe->len = BS;
	} else {
		sqe->opcode = IORING_OP_READV;
		sqe->addr = &s->iovecs[index];
		sqe->len = 1;
	}
	sqe->flags = 0;
	sqe->ioprio = 0;
	sqe->fd = fd;
	sqe->off = offset;
}

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

	head = *ring->head;
	do {
		barrier();
		if (head == *ring->tail)
			break;
		cqe = &ring->cqes[head & cq_ring_mask];
		if (cqe->res != BS) {
			struct io_uring_sqe *sqe = &s->sqes[cqe->index];

			printf("io: unexpected ret=%d\n", cqe->res);
			printf("offset=%lu, size=%lu\n",
					(unsigned long) sqe->off,
					(unsigned long) sqe->len);
			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;
	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 io_sq_ring *sring = &s->sq_ring;
	struct io_cq_ring *cring = &s->cq_ring;
	struct io_uring_params p;
	void *ptr;
	int fd;

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

	if (polled)
		p.flags |= IORING_SETUP_IOPOLL;
	if (buffered)
		p.flags |= IORING_SETUP_SQWQ;
	else if (sq_thread) {
		p.flags |= IORING_SETUP_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->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;
	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);
	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/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 *array;
	37	};
	38
	39	struct io_cq_ring {
	40	unsigned *head;
	41	unsigned *tail;
	42	unsigned *ring_mask;
	43	unsigned *ring_entries;
	44	struct io_uring_cqe *cqes;
	45	};
	46
	47	#define DEPTH 32
	48
	49	#define BATCH_SUBMIT 8
	50	#define BATCH_COMPLETE 8
	51
	52	#define BS 4096
	53
	54	static unsigned sq_ring_mask, cq_ring_mask;
	55
	56	struct submitter {
	57	pthread_t thread;
	58	unsigned long max_blocks;
	59	int ring_fd;
	60	struct drand48_data rand;
	61	struct io_sq_ring sq_ring;
	62	struct io_uring_sqe *sqes;
	63	struct iovec iovecs[DEPTH];
	64	struct io_cq_ring cq_ring;
	65	int inflight;
	66	unsigned long reaps;
	67	unsigned long done;
	68	unsigned long calls;
	69	unsigned long cachehit, cachemiss;
	70	volatile int finish;
	71	char filename[128];
	72	};
	73
	74	static struct submitter submitters[1];
	75	static volatile int finish;
	76
	77	static int polled = 1; /* use IO polling */
	78	static int fixedbufs = 0; /* use fixed user buffers */
	79	static int buffered = 0; /* use buffered IO, not O_DIRECT */
	80	static int sq_thread = 0; /* use kernel submission thread */
	81	static int sq_thread_cpu = 0; /* pin above thread to this CPU */
	82
	83	static int io_uring_setup(unsigned entries, struct iovec *iovecs,
	84	struct io_uring_params *p)
	85	{
	86	return syscall(__NR_sys_io_uring_setup, entries, iovecs, p);
	87	}
	88
	89	static int io_uring_enter(struct submitter *s, unsigned int to_submit,
	90	unsigned int min_complete, unsigned int flags)
	91	{
	92	return syscall(__NR_sys_io_uring_enter, s->ring_fd, to_submit,
	93	min_complete, flags);
	94	}
	95
	96	static int gettid(void)
	97	{
	98	return syscall(__NR_gettid);
	99	}
	100
	101	static void init_io(struct submitter *s, int fd, unsigned index)
	102	{
	103	struct io_uring_sqe *sqe = &s->sqes[index];
	104	unsigned long offset;
	105	long r;
	106
	107	lrand48_r(&s->rand, &r);
	108	offset = (r % (s->max_blocks - 1)) * BS;
	109
	110	if (fixedbufs) {
	111	sqe->opcode = IORING_OP_READ_FIXED;
	112	sqe->addr = s->iovecs[index].iov_base;
	113	sqe->len = BS;
	114	} else {
	115	sqe->opcode = IORING_OP_READV;
	116	sqe->addr = &s->iovecs[index];
	117	sqe->len = 1;
	118	}
	119	sqe->flags = 0;
	120	sqe->ioprio = 0;
	121	sqe->fd = fd;
	122	sqe->off = offset;
	123	}
	124
	125	static int prep_more_ios(struct submitter *s, int fd, int max_ios)
	126	{
	127	struct io_sq_ring *ring = &s->sq_ring;
	128	unsigned index, tail, next_tail, prepped = 0;
	129
	130	next_tail = tail = *ring->tail;
	131	do {
	132	next_tail++;
	133	barrier();
	134	if (next_tail == *ring->head)
	135	break;
	136
	137	index = tail & sq_ring_mask;
	138	init_io(s, fd, index);
	139	ring->array[index] = index;
	140	prepped++;
	141	tail = next_tail;
	142	} while (prepped < max_ios);
	143
	144	if (*ring->tail != tail) {
	145	/* order tail store with writes to sqes above */
	146	barrier();
	147	*ring->tail = tail;
	148	barrier();
	149	}
	150	return prepped;
	151	}
	152
	153	static int get_file_size(int fd, unsigned long *blocks)
	154	{
	155	struct stat st;
	156
	157	if (fstat(fd, &st) < 0)
	158	return -1;
	159	if (S_ISBLK(st.st_mode)) {
	160	unsigned long long bytes;
	161
	162	if (ioctl(fd, BLKGETSIZE64, &bytes) != 0)
	163	return -1;
	164
	165	*blocks = bytes / BS;
	166	return 0;
	167	} else if (S_ISREG(st.st_mode)) {
	168	*blocks = st.st_size / BS;
	169	return 0;
	170	}
	171
	172	return -1;
	173	}
	174
	175	static int reap_events(struct submitter *s)
	176	{
	177	struct io_cq_ring *ring = &s->cq_ring;
	178	struct io_uring_cqe *cqe;
	179	unsigned head, reaped = 0;
	180
	181	head = *ring->head;
	182	do {
	183	barrier();
	184	if (head == *ring->tail)
	185	break;
	186	cqe = &ring->cqes[head & cq_ring_mask];
	187	if (cqe->res != BS) {
	188	struct io_uring_sqe *sqe = &s->sqes[cqe->index];
	189
	190	printf("io: unexpected ret=%d\n", cqe->res);
	191	printf("offset=%lu, size=%lu\n",
	192	(unsigned long) sqe->off,
	193	(unsigned long) sqe->len);
	194	return -1;
	195	}
	196	if (cqe->flags & IOCQE_FLAG_CACHEHIT)
	197	s->cachehit++;
	198	else
	199	s->cachemiss++;
	200	reaped++;
	201	head++;
	202	} while (1);
	203
	204	s->inflight -= reaped;
	205	*ring->head = head;
	206	barrier();
	207	return reaped;
	208	}
	209
	210	static void submitter_fn(void data)
	211	{
	212	struct submitter *s = data;
	213	int fd, ret, prepped, flags;
	214
	215	printf("submitter=%d\n", gettid());
	216
	217	flags = O_RDONLY;
	218	if (!buffered)
	219	flags \|= O_DIRECT;
	220	fd = open(s->filename, flags);
	221	if (fd < 0) {
	222	perror("open");
	223	goto done;
	224	}
	225
	226	if (get_file_size(fd, &s->max_blocks)) {
	227	printf("failed getting size of device/file\n");
	228	goto err;
	229	}
	230	if (s->max_blocks <= 1) {
	231	printf("Zero file/device size?\n");
	232	goto err;
	233	}
	234	s->max_blocks--;
	235
	236	srand48_r(pthread_self(), &s->rand);
	237
	238	prepped = 0;
	239	do {
	240	int to_wait, to_submit, this_reap, to_prep;
	241
	242	if (!prepped && s->inflight < DEPTH) {
	243	to_prep = min(DEPTH - s->inflight, BATCH_SUBMIT);
	244	prepped = prep_more_ios(s, fd, to_prep);
	245	}
	246	s->inflight += prepped;
	247	submit_more:
	248	to_submit = prepped;
	249	submit:
	250	if (s->inflight + BATCH_SUBMIT < DEPTH)
	251	to_wait = 0;
	252	else
	253	to_wait = min(s->inflight + to_submit, BATCH_COMPLETE);
	254
	255	ret = io_uring_enter(s, to_submit, to_wait,
	256	IORING_ENTER_GETEVENTS);
	257	s->calls++;
	258
	259	this_reap = reap_events(s);
	260	if (this_reap == -1)
	261	break;
	262	s->reaps += this_reap;
	263
	264	if (ret >= 0) {
	265	if (!ret) {
	266	to_submit = 0;
	267	if (s->inflight)
	268	goto submit;
	269	continue;
	270	} else if (ret < to_submit) {
	271	int diff = to_submit - ret;
	272
	273	s->done += ret;
	274	prepped -= diff;
	275	goto submit_more;
	276	}
	277	s->done += ret;
	278	prepped = 0;
	279	continue;
	280	} else if (ret < 0) {
	281	if (errno == EAGAIN) {
	282	if (s->finish)
	283	break;
	284	if (this_reap)
	285	goto submit;
	286	to_submit = 0;
	287	goto submit;
	288	}
	289	printf("io_submit: %s\n", strerror(errno));
	290	break;
	291	}
	292	} while (!s->finish);
	293	err:
	294	close(fd);
	295	done:
	296	finish = 1;
	297	return NULL;
	298	}
	299
	300	static void sig_int(int sig)
	301	{
	302	printf("Exiting on signal %d\n", sig);
	303	submitters[0].finish = 1;
	304	finish = 1;
	305	}
	306
	307	static void arm_sig_int(void)
	308	{
	309	struct sigaction act;
	310
	311	memset(&act, 0, sizeof(act));
	312	act.sa_handler = sig_int;
	313	act.sa_flags = SA_RESTART;
	314	sigaction(SIGINT, &act, NULL);
	315	}
	316
	317	static int setup_ring(struct submitter *s)
	318	{
	319	struct io_sq_ring *sring = &s->sq_ring;
	320	struct io_cq_ring *cring = &s->cq_ring;
	321	struct io_uring_params p;
	322	void *ptr;
	323	int fd;
	324
	325	memset(&p, 0, sizeof(p));
	326
	327	if (polled)
	328	p.flags \|= IORING_SETUP_IOPOLL;
	329	if (buffered)
	330	p.flags \|= IORING_SETUP_SQWQ;
	331	else if (sq_thread) {
	332	p.flags \|= IORING_SETUP_SQTHREAD;
	333	p.sq_thread_cpu = sq_thread_cpu;
	334	}
	335
	336	if (fixedbufs)
	337	fd = io_uring_setup(DEPTH, s->iovecs, &p);
	338	else
	339	fd = io_uring_setup(DEPTH, NULL, &p);
	340	if (fd < 0) {
	341	perror("io_uring_setup");
	342	return 1;
	343	}
	344
	345	s->ring_fd = fd;
	346	ptr = mmap(0, p.sq_off.array + p.sq_entries * sizeof(__u32),
	347	PROT_READ \| PROT_WRITE, MAP_SHARED \| MAP_POPULATE, fd,
	348	IORING_OFF_SQ_RING);
	349	printf("sq_ring ptr = 0x%p\n", ptr);
	350	sring->head = ptr + p.sq_off.head;
	351	sring->tail = ptr + p.sq_off.tail;
	352	sring->ring_mask = ptr + p.sq_off.ring_mask;
	353	sring->ring_entries = ptr + p.sq_off.ring_entries;
	354	sring->array = ptr + p.sq_off.array;
	355	sq_ring_mask = *sring->ring_mask;
	356
	357	s->sqes = mmap(0, p.sq_entries * sizeof(struct io_uring_sqe),
	358	PROT_READ \| PROT_WRITE, MAP_SHARED \| MAP_POPULATE, fd,
	359	IORING_OFF_SQES);
	360	printf("sqes ptr = 0x%p\n", s->sqes);
	361
	362	ptr = mmap(0, p.cq_off.cqes + p.cq_entries * sizeof(struct io_uring_cqe),
	363	PROT_READ \| PROT_WRITE, MAP_SHARED \| MAP_POPULATE, fd,
	364	IORING_OFF_CQ_RING);
	365	printf("cq_ring ptr = 0x%p\n", ptr);
	366	cring->head = ptr + p.cq_off.head;
	367	cring->tail = ptr + p.cq_off.tail;
	368	cring->ring_mask = ptr + p.cq_off.ring_mask;
	369	cring->ring_entries = ptr + p.cq_off.ring_entries;
	370	cring->cqes = ptr + p.cq_off.cqes;
	371	cq_ring_mask = *cring->ring_mask;
	372	return 0;
	373	}
	374
	375	int main(int argc, char *argv[])
	376	{
	377	struct submitter *s = &submitters[0];
	378	unsigned long done, calls, reap, cache_hit, cache_miss;
	379	int err, i;
	380	struct rlimit rlim;
	381	void *ret;
	382
	383	if (argc < 2) {
	384	printf("%s: filename\n", argv[0]);
	385	return 1;
	386	}
	387
	388	rlim.rlim_cur = RLIM_INFINITY;
	389	rlim.rlim_max = RLIM_INFINITY;
	390	if (setrlimit(RLIMIT_MEMLOCK, &rlim) < 0) {
	391	perror("setrlimit");
	392	return 1;
	393	}
	394
	395	arm_sig_int();
	396
	397	for (i = 0; i < DEPTH; i++) {
	398	void *buf;
	399
	400	if (posix_memalign(&buf, BS, BS)) {
	401	printf("failed alloc\n");
	402	return 1;
	403	}
	404	s->iovecs[i].iov_base = buf;
	405	s->iovecs[i].iov_len = BS;
	406	}
	407
	408	err = setup_ring(s);
	409	if (err) {
	410	printf("ring setup failed: %s, %d\n", strerror(errno), err);
	411	return 1;
	412	}
	413	printf("polled=%d, fixedbufs=%d, buffered=%d", polled, fixedbufs, buffered);
	414	printf(" QD=%d, sq_ring=%d, cq_ring=%d\n", DEPTH, s->sq_ring.ring_entries, s->cq_ring.ring_entries);
	415	strcpy(s->filename, argv[1]);
	416
	417	pthread_create(&s->thread, NULL, submitter_fn, s);
	418
	419	cache_hit = cache_miss = reap = calls = done = 0;
	420	do {
	421	unsigned long this_done = 0;
	422	unsigned long this_reap = 0;
	423	unsigned long this_call = 0;
	424	unsigned long this_cache_hit = 0;
	425	unsigned long this_cache_miss = 0;
	426	unsigned long rpc = 0, ipc = 0;
	427	double hit = 0.0;
	428
	429	sleep(1);
	430	this_done += s->done;
	431	this_call += s->calls;
	432	this_reap += s->reaps;
	433	this_cache_hit += s->cachehit;
	434	this_cache_miss += s->cachemiss;
	435	if (this_cache_hit && this_cache_miss) {
	436	unsigned long hits, total;
	437
	438	hits = this_cache_hit - cache_hit;
	439	total = hits + this_cache_miss - cache_miss;
	440	hit = (double) hits / (double) total;
	441	hit *= 100.0;
	442	}
	443	if (this_call - calls) {
	444	rpc = (this_done - done) / (this_call - calls);
	445	ipc = (this_reap - reap) / (this_call - calls);
	446	}
	447	printf("IOPS=%lu, IOS/call=%lu/%lu, inflight=%u (head=%u tail=%u), Cachehit=%0.2f%%\n",
	448	this_done - done, rpc, ipc, s->inflight,
	449	s->cq_ring.head, s->cq_ring.tail, hit);
	450	done = this_done;
	451	calls = this_call;
	452	reap = this_reap;
	453	cache_hit = s->cachehit;
	454	cache_miss = s->cachemiss;
	455	} while (!finish);
	456
	457	pthread_join(s->thread, &ret);
	458	close(s->ring_fd);
	459	return 0;
	460	}