[fio.git] / engines / aioring.c

#ifdef ARCH_HAVE_AIORING
/*
 * aioring engine
 *
 * IO engine using the new native Linux libaio ring interface
 *
 */
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <libaio.h>
#include <sys/time.h>
#include <sys/resource.h>

#include "../fio.h"
#include "../lib/pow2.h"
#include "../optgroup.h"
#include "../lib/memalign.h"

#ifndef IOCB_FLAG_HIPRI
#define IOCB_FLAG_HIPRI	(1 << 2)
#endif

/*
 * io_setup2(2) flags
 */
#ifndef IOCTX_FLAG_IOPOLL
#define IOCTX_FLAG_IOPOLL	(1 << 0)
#endif
#ifndef IOCTX_FLAG_SCQRING
#define IOCTX_FLAG_SCQRING	(1 << 1)
#endif
#ifndef IOCTX_FLAG_FIXEDBUFS
#define IOCTX_FLAG_FIXEDBUFS	(1 << 2)
#endif
#ifndef IOCTX_FLAG_SQTHREAD
#define IOCTX_FLAG_SQTHREAD	(1 << 3)
#endif
#ifndef IOCTX_FLAG_SQWQ
#define IOCTX_FLAG_SQWQ		(1 << 4)
#endif

/*
 * io_ring_enter(2) flags
 */
#ifndef IORING_FLAG_SUBMIT
#define IORING_FLAG_SUBMIT	(1 << 0)
#endif
#ifndef IORING_FLAG_GETEVENTS
#define IORING_FLAG_GETEVENTS	(1 << 1)
#endif

typedef uint64_t u64;
typedef uint32_t u32;
typedef uint16_t u16;

struct aio_sq_ring {
	union {
		struct {
			u32 head;
			u32 tail;
			u32 nr_events;
			u16 sq_thread_cpu;
			u64 iocbs;
		};
		u32 pad[16];
	};
	u32 array[0];
};

struct aio_cq_ring {
	union {
		struct {
			u32 head;
			u32 tail;
			u32 nr_events;
		};
		struct io_event pad;
	};
	struct io_event events[0];
};

struct aioring_data {
	io_context_t aio_ctx;
	struct io_u **io_us;
	struct io_u **io_u_index;

	struct aio_sq_ring *sq_ring;
	struct iocb *iocbs;

	struct aio_cq_ring *cq_ring;
	struct io_event *events;

	int queued;
	int cq_ring_off;
};

struct aioring_options {
	void *pad;
	unsigned int hipri;
	unsigned int fixedbufs;
};

static struct fio_option options[] = {
	{
		.name	= "hipri",
		.lname	= "High Priority",
		.type	= FIO_OPT_STR_SET,
		.off1	= offsetof(struct aioring_options, hipri),
		.help	= "Use polled IO completions",
		.category = FIO_OPT_C_ENGINE,
		.group	= FIO_OPT_G_LIBAIO,
	},
	{
		.name	= "fixedbufs",
		.lname	= "Fixed (pre-mapped) IO buffers",
		.type	= FIO_OPT_STR_SET,
		.off1	= offsetof(struct aioring_options, fixedbufs),
		.help	= "Pre map IO buffers",
		.category = FIO_OPT_C_ENGINE,
		.group	= FIO_OPT_G_LIBAIO,
	},
	{
		.name	= NULL,
	},
};

static int fio_aioring_commit(struct thread_data *td);

static int io_ring_enter(io_context_t ctx, unsigned int to_submit,
			 unsigned int min_complete, unsigned int flags)
{
#ifdef __NR_sys_io_ring_enter
	return syscall(__NR_sys_io_ring_enter, ctx, to_submit, min_complete,
			flags);
#else
	return -1;
#endif
}

static int fio_aioring_prep(struct thread_data *td, struct io_u *io_u)
{
	struct aioring_data *ld = td->io_ops_data;
	struct fio_file *f = io_u->file;
	struct aioring_options *o = td->eo;
	struct iocb *iocb;

	iocb = &ld->iocbs[io_u->index];

	if (io_u->ddir == DDIR_READ) {
		if (o->fixedbufs) {
			iocb->aio_fildes = f->fd;
			iocb->aio_lio_opcode = IO_CMD_PREAD;
			iocb->u.c.offset = io_u->offset;
		} else {
			io_prep_pread(iocb, f->fd, io_u->xfer_buf, io_u->xfer_buflen, io_u->offset);
			if (o->hipri)
				iocb->u.c.flags |= IOCB_FLAG_HIPRI;
		}
	} else if (io_u->ddir == DDIR_WRITE) {
		if (o->fixedbufs) {
			iocb->aio_fildes = f->fd;
			iocb->aio_lio_opcode = IO_CMD_PWRITE;
			iocb->u.c.offset = io_u->offset;
		} else {
			io_prep_pwrite(iocb, f->fd, io_u->xfer_buf, io_u->xfer_buflen, io_u->offset);
			if (o->hipri)
				iocb->u.c.flags |= IOCB_FLAG_HIPRI;
		}
	} else if (ddir_sync(io_u->ddir))
		io_prep_fsync(iocb, f->fd);

	iocb->data = io_u;
	return 0;
}

static struct io_u *fio_aioring_event(struct thread_data *td, int event)
{
	struct aioring_data *ld = td->io_ops_data;
	struct io_event *ev;
	struct io_u *io_u;
	int index;

	index = event + ld->cq_ring_off;
	if (index >= ld->cq_ring->nr_events)
		index -= ld->cq_ring->nr_events;

	ev = &ld->cq_ring->events[index];
	io_u = ev->data;

	if (ev->res != io_u->xfer_buflen) {
		if (ev->res > io_u->xfer_buflen)
			io_u->error = -ev->res;
		else
			io_u->resid = io_u->xfer_buflen - ev->res;
	} else
		io_u->error = 0;

	return io_u;
}

static int fio_aioring_cqring_reap(struct thread_data *td, unsigned int events,
				   unsigned int max)
{
	struct aioring_data *ld = td->io_ops_data;
	struct aio_cq_ring *ring = ld->cq_ring;
	u32 head, reaped = 0;

	head = ring->head;
	do {
		read_barrier();
		if (head == ring->tail)
			break;
		reaped++;
		head++;
		if (head == ring->nr_events)
			head = 0;
	} while (reaped + events < max);

	ring->head = head;
	write_barrier();
	return reaped;
}

static int fio_aioring_getevents(struct thread_data *td, unsigned int min,
				 unsigned int max, const struct timespec *t)
{
	struct aioring_data *ld = td->io_ops_data;
	unsigned actual_min = td->o.iodepth_batch_complete_min == 0 ? 0 : min;
	struct aio_cq_ring *ring = ld->cq_ring;
	int r, events = 0;

	ld->cq_ring_off = ring->head;
	do {
		r = fio_aioring_cqring_reap(td, events, max);
		if (r) {
			events += r;
			continue;
		}

		r = io_ring_enter(ld->aio_ctx, 0, actual_min,
					IORING_FLAG_GETEVENTS);
		if (r < 0) {
			if (errno == EAGAIN)
				continue;
			perror("ring enter");
			break;
		}
	} while (events < min);

	return r < 0 ? r : events;
}

static enum fio_q_status fio_aioring_queue(struct thread_data *td,
					   struct io_u *io_u)
{
	struct aioring_data *ld = td->io_ops_data;
	struct aio_sq_ring *ring = ld->sq_ring;
	unsigned tail, next_tail;

	fio_ro_check(td, io_u);

	if (ld->queued == td->o.iodepth)
		return FIO_Q_BUSY;

	/*
	 * fsync is tricky, since it can fail and we need to do it
	 * serialized with other io. the reason is that linux doesn't
	 * support aio fsync yet. So return busy for the case where we
	 * have pending io, to let fio complete those first.
	 */
	if (ddir_sync(io_u->ddir)) {
		if (ld->queued)
			return FIO_Q_BUSY;

		do_io_u_sync(td, io_u);
		return FIO_Q_COMPLETED;
	}

	if (io_u->ddir == DDIR_TRIM) {
		if (ld->queued)
			return FIO_Q_BUSY;

		do_io_u_trim(td, io_u);
		io_u_mark_submit(td, 1);
		io_u_mark_complete(td, 1);
		return FIO_Q_COMPLETED;
	}

	tail = ring->tail;
	next_tail = tail + 1;
	if (next_tail == ring->nr_events)
		next_tail = 0;
	read_barrier();
	if (next_tail == ring->head)
		return FIO_Q_BUSY;

	ring->array[tail] = io_u->index;
	ring->tail = next_tail;
	write_barrier();

	ld->queued++;
	return FIO_Q_QUEUED;
}

static void fio_aioring_queued(struct thread_data *td, int start, int nr)
{
	struct aioring_data *ld = td->io_ops_data;
	struct timespec now;

	if (!fio_fill_issue_time(td))
		return;

	fio_gettime(&now, NULL);

	while (nr--) {
		int index = ld->sq_ring->array[start];
		struct io_u *io_u = io_u = ld->io_u_index[index];

		memcpy(&io_u->issue_time, &now, sizeof(now));
		io_u_queued(td, io_u);

		start++;
		if (start == ld->sq_ring->nr_events)
			start = 0;
	}
}

static int fio_aioring_commit(struct thread_data *td)
{
	struct aioring_data *ld = td->io_ops_data;
	int ret;

	if (!ld->queued)
		return 0;

	do {
		int start = ld->sq_ring->head;
		long nr = ld->queued;

		ret = io_ring_enter(ld->aio_ctx, nr, 0, IORING_FLAG_SUBMIT |
						IORING_FLAG_GETEVENTS);
		if (ret == -1)
			perror("io_ring_enter");
		if (ret > 0) {
			fio_aioring_queued(td, start, ret);
			io_u_mark_submit(td, ret);

			ld->queued -= ret;
			ret = 0;
		} else if (ret == -EINTR || !ret) {
			if (!ret)
				io_u_mark_submit(td, ret);
			continue;
		} else if (ret == -EAGAIN) {
			/*
			 * If we get EAGAIN, we should break out without
			 * error and let the upper layer reap some
			 * events for us. If we have no queued IO, we
			 * must loop here. If we loop for more than 30s,
			 * just error out, something must be buggy in the
			 * IO path.
			 */
			if (ld->queued) {
				ret = 0;
				break;
			}
			usleep(1);
			continue;
		} else if (ret == -ENOMEM) {
			/*
			 * If we get -ENOMEM, reap events if we can. If
			 * we cannot, treat it as a fatal event since there's
			 * nothing we can do about it.
			 */
			if (ld->queued)
				ret = 0;
			break;
		} else
			break;
	} while (ld->queued);

	return ret;
}

static size_t aioring_cq_size(struct thread_data *td)
{
	return sizeof(struct aio_cq_ring) + 2 * td->o.iodepth * sizeof(struct io_event);
}

static size_t aioring_sq_iocb(struct thread_data *td)
{
	return sizeof(struct iocb) * td->o.iodepth;
}

static size_t aioring_sq_size(struct thread_data *td)
{
	return sizeof(struct aio_sq_ring) + td->o.iodepth * sizeof(u32);
}

static void fio_aioring_cleanup(struct thread_data *td)
{
	struct aioring_data *ld = td->io_ops_data;

	if (ld) {
		/*
		 * Work-around to avoid huge RCU stalls at exit time. If we
		 * don't do this here, then it'll be torn down by exit_aio().
		 * But for that case we can parallellize the freeing, thus
		 * speeding it up a lot.
		 */
		if (!(td->flags & TD_F_CHILD))
			io_destroy(ld->aio_ctx);
		free(ld->io_u_index);
		free(ld->io_us);
		fio_memfree(ld->sq_ring, aioring_sq_size(td), false);
		fio_memfree(ld->iocbs, aioring_sq_iocb(td), false);
		fio_memfree(ld->cq_ring, aioring_cq_size(td), false);
		free(ld);
	}
}

static int fio_aioring_queue_init(struct thread_data *td)
{
#ifdef __NR_sys_io_setup2
	struct aioring_data *ld = td->io_ops_data;
	struct aioring_options *o = td->eo;
	int flags = IOCTX_FLAG_SCQRING;
	int depth = td->o.iodepth;

	if (o->hipri)
		flags |= IOCTX_FLAG_IOPOLL;
	if (o->fixedbufs) {
		struct rlimit rlim = {
			.rlim_cur = RLIM_INFINITY,
			.rlim_max = RLIM_INFINITY,
		};

		setrlimit(RLIMIT_MEMLOCK, &rlim);
		flags |= IOCTX_FLAG_FIXEDBUFS;
	}

	return syscall(__NR_sys_io_setup2, depth, flags,
			ld->sq_ring, ld->cq_ring, &ld->aio_ctx);
#else
	return -1;
#endif
}

static int fio_aioring_post_init(struct thread_data *td)
{
	struct aioring_data *ld = td->io_ops_data;
	struct aioring_options *o = td->eo;
	struct io_u *io_u;
	struct iocb *iocb;
	int err = 0;

	if (o->fixedbufs) {
		int i;

		for (i = 0; i < td->o.iodepth; i++) {
			io_u = ld->io_u_index[i];
			iocb = &ld->iocbs[i];
			iocb->u.c.buf = io_u->buf;
			iocb->u.c.nbytes = td_max_bs(td);

			if (o->hipri)
				iocb->u.c.flags |= IOCB_FLAG_HIPRI;
		}
	}

	err = fio_aioring_queue_init(td);
	if (err) {
		td_verror(td, -err, "io_queue_init");
		return 1;
	}

	return 0;
}

static int fio_aioring_init(struct thread_data *td)
{
	struct aioring_data *ld;

	if (td->o.iodepth <= 1) {
		printf("aio-ring: needs a minimum QD of 2\n");
		return 1;
	}

	ld = calloc(1, sizeof(*ld));

	/* io_u index */
	ld->io_u_index = calloc(td->o.iodepth, sizeof(struct io_u *));
	ld->io_us = calloc(td->o.iodepth, sizeof(struct io_u *));

	ld->iocbs = fio_memalign(page_size, aioring_sq_iocb(td), false);
	memset(ld->iocbs, 0, aioring_sq_iocb(td));

	ld->sq_ring = fio_memalign(page_size, aioring_sq_size(td), false);
	memset(ld->sq_ring, 0, aioring_sq_size(td));
	ld->sq_ring->nr_events = td->o.iodepth;
	ld->sq_ring->iocbs = (u64) (uintptr_t) ld->iocbs;

	ld->cq_ring = fio_memalign(page_size, aioring_cq_size(td), false);
	memset(ld->cq_ring, 0, aioring_cq_size(td));
	ld->cq_ring->nr_events = td->o.iodepth * 2;

	td->io_ops_data = ld;
	return 0;
}

static int fio_aioring_io_u_init(struct thread_data *td, struct io_u *io_u)
{
	struct aioring_data *ld = td->io_ops_data;

	ld->io_u_index[io_u->index] = io_u;
	return 0;
}

static struct ioengine_ops ioengine = {
	.name			= "aio-ring",
	.version		= FIO_IOOPS_VERSION,
	.init			= fio_aioring_init,
	.post_init		= fio_aioring_post_init,
	.io_u_init		= fio_aioring_io_u_init,
	.prep			= fio_aioring_prep,
	.queue			= fio_aioring_queue,
	.commit			= fio_aioring_commit,
	.getevents		= fio_aioring_getevents,
	.event			= fio_aioring_event,
	.cleanup		= fio_aioring_cleanup,
	.open_file		= generic_open_file,
	.close_file		= generic_close_file,
	.get_file_size		= generic_get_file_size,
	.options		= options,
	.option_struct_size	= sizeof(struct aioring_options),
};

static void fio_init fio_aioring_register(void)
{
	register_ioengine(&ioengine);
}

static void fio_exit fio_aioring_unregister(void)
{
	unregister_ioengine(&ioengine);
}
#endif
Commit	Line	Data
1f90e9bb	1	#ifdef ARCH_HAVE_AIORING
52885fa2 JA	2	/*
	3	* aioring engine
	4	*
	5	* IO engine using the new native Linux libaio ring interface
	6	*
	7	*/
	8	#include <stdlib.h>
	9	#include <unistd.h>
	10	#include <errno.h>
	11	#include <libaio.h>
	12	#include <sys/time.h>
	13	#include <sys/resource.h>
	14
	15	#include "../fio.h"
	16	#include "../lib/pow2.h"
	17	#include "../optgroup.h"
	18	#include "../lib/memalign.h"
	19
	20	#ifndef IOCB_FLAG_HIPRI
	21	#define IOCB_FLAG_HIPRI (1 << 2)
	22	#endif
	23
	24	/*
	25	* io_setup2(2) flags
	26	*/
	27	#ifndef IOCTX_FLAG_IOPOLL
	28	#define IOCTX_FLAG_IOPOLL (1 << 0)
	29	#endif
	30	#ifndef IOCTX_FLAG_SCQRING
	31	#define IOCTX_FLAG_SCQRING (1 << 1)
	32	#endif
	33	#ifndef IOCTX_FLAG_FIXEDBUFS
	34	#define IOCTX_FLAG_FIXEDBUFS (1 << 2)
	35	#endif
	36	#ifndef IOCTX_FLAG_SQTHREAD
	37	#define IOCTX_FLAG_SQTHREAD (1 << 3)
	38	#endif
	39	#ifndef IOCTX_FLAG_SQWQ
	40	#define IOCTX_FLAG_SQWQ (1 << 4)
	41	#endif
	42
	43	/*
	44	* io_ring_enter(2) flags
	45	*/
	46	#ifndef IORING_FLAG_SUBMIT
	47	#define IORING_FLAG_SUBMIT (1 << 0)
	48	#endif
	49	#ifndef IORING_FLAG_GETEVENTS
	50	#define IORING_FLAG_GETEVENTS (1 << 1)
	51	#endif
	52
	53	typedef uint64_t u64;
	54	typedef uint32_t u32;
	55	typedef uint16_t u16;
	56
	57	struct aio_sq_ring {
	58	union {
	59	struct {
	60	u32 head;
	61	u32 tail;
	62	u32 nr_events;
	63	u16 sq_thread_cpu;
	64	u64 iocbs;
	65	};
66	u32 pad[16];
67	};
68	u32 array[0];
69	};
70
71	struct aio_cq_ring {
72	union {
73	struct {
74	u32 head;
75	u32 tail;
76	u32 nr_events;
77	};
78	struct io_event pad;
79	};
80	struct io_event events[0];
81	};
82
83	struct aioring_data {
84	io_context_t aio_ctx;
85	struct io_u **io_us;
86	struct io_u **io_u_index;
87
88	struct aio_sq_ring *sq_ring;
89	struct iocb *iocbs;
90
91	struct aio_cq_ring *cq_ring;
92	struct io_event *events;
93
94	int queued;
95	int cq_ring_off;
96	};
97
98	struct aioring_options {
99	void *pad;
100	unsigned int hipri;
101	unsigned int fixedbufs;
102	};
103
104	static struct fio_option options[] = {
105	{
106	.name = "hipri",
107	.lname = "High Priority",
108	.type = FIO_OPT_STR_SET,
109	.off1 = offsetof(struct aioring_options, hipri),
110	.help = "Use polled IO completions",
111	.category = FIO_OPT_C_ENGINE,
112	.group = FIO_OPT_G_LIBAIO,
113	},
114	{
115	.name = "fixedbufs",
116	.lname = "Fixed (pre-mapped) IO buffers",
117	.type = FIO_OPT_STR_SET,
118	.off1 = offsetof(struct aioring_options, fixedbufs),
119	.help = "Pre map IO buffers",
120	.category = FIO_OPT_C_ENGINE,
121	.group = FIO_OPT_G_LIBAIO,
122	},
123	{
124	.name = NULL,
125	},
126	};
127
128	static int fio_aioring_commit(struct thread_data *td);
129
130	static int io_ring_enter(io_context_t ctx, unsigned int to_submit,
131	unsigned int min_complete, unsigned int flags)
132	{
133	#ifdef __NR_sys_io_ring_enter
134	return syscall(__NR_sys_io_ring_enter, ctx, to_submit, min_complete,
135	flags);
136	#else
137	return -1;
138	#endif
139	}
140
141	static int fio_aioring_prep(struct thread_data td, struct io_u io_u)
142	{
143	struct aioring_data *ld = td->io_ops_data;
144	struct fio_file *f = io_u->file;
145	struct aioring_options *o = td->eo;
146	struct iocb *iocb;
147
148	iocb = &ld->iocbs[io_u->index];
149
150	if (io_u->ddir == DDIR_READ) {
151	if (o->fixedbufs) {
152	iocb->aio_fildes = f->fd;
153	iocb->aio_lio_opcode = IO_CMD_PREAD;
154	iocb->u.c.offset = io_u->offset;
155	} else {
156	io_prep_pread(iocb, f->fd, io_u->xfer_buf, io_u->xfer_buflen, io_u->offset);
157	if (o->hipri)
158	iocb->u.c.flags \|= IOCB_FLAG_HIPRI;
159	}
160	} else if (io_u->ddir == DDIR_WRITE) {
161	if (o->fixedbufs) {
162	iocb->aio_fildes = f->fd;
163	iocb->aio_lio_opcode = IO_CMD_PWRITE;
164	iocb->u.c.offset = io_u->offset;
165	} else {
166	io_prep_pwrite(iocb, f->fd, io_u->xfer_buf, io_u->xfer_buflen, io_u->offset);
167	if (o->hipri)
168	iocb->u.c.flags \|= IOCB_FLAG_HIPRI;
169	}
170	} else if (ddir_sync(io_u->ddir))
171	io_prep_fsync(iocb, f->fd);
172
173	iocb->data = io_u;
174	return 0;
175	}
176
177	static struct io_u fio_aioring_event(struct thread_data td, int event)
178	{
179	struct aioring_data *ld = td->io_ops_data;
180	struct io_event *ev;
181	struct io_u *io_u;
182	int index;
183
184	index = event + ld->cq_ring_off;
185	if (index >= ld->cq_ring->nr_events)
186	index -= ld->cq_ring->nr_events;
187
188	ev = &ld->cq_ring->events[index];
189	io_u = ev->data;
190
191	if (ev->res != io_u->xfer_buflen) {
192	if (ev->res > io_u->xfer_buflen)
193	io_u->error = -ev->res;
194	else
195	io_u->resid = io_u->xfer_buflen - ev->res;
196	} else
197	io_u->error = 0;
198
199	return io_u;
200	}
201
202	static int fio_aioring_cqring_reap(struct thread_data *td, unsigned int events,
203	unsigned int max)
204	{
205	struct aioring_data *ld = td->io_ops_data;
206	struct aio_cq_ring *ring = ld->cq_ring;
207	u32 head, reaped = 0;
208
209	head = ring->head;
210	do {
211	read_barrier();
212	if (head == ring->tail)
213	break;
214	reaped++;
215	head++;
216	if (head == ring->nr_events)
217	head = 0;
218	} while (reaped + events < max);
219
220	ring->head = head;
221	write_barrier();
222	return reaped;
223	}
224
225	static int fio_aioring_getevents(struct thread_data *td, unsigned int min,
226	unsigned int max, const struct timespec *t)
227	{
228	struct aioring_data *ld = td->io_ops_data;
229	unsigned actual_min = td->o.iodepth_batch_complete_min == 0 ? 0 : min;
230	struct aio_cq_ring *ring = ld->cq_ring;
231	int r, events = 0;
232
233	ld->cq_ring_off = ring->head;
234	do {
235	r = fio_aioring_cqring_reap(td, events, max);
236	if (r) {
237	events += r;
238	continue;
239	}
240
241	r = io_ring_enter(ld->aio_ctx, 0, actual_min,
242	IORING_FLAG_GETEVENTS);
243	if (r < 0) {
244	if (errno == EAGAIN)
245	continue;
246	perror("ring enter");
247	break;
248	}
249	} while (events < min);
250
251	return r < 0 ? r : events;
252	}
253
254	static enum fio_q_status fio_aioring_queue(struct thread_data *td,
255	struct io_u *io_u)
256	{
257	struct aioring_data *ld = td->io_ops_data;
258	struct aio_sq_ring *ring = ld->sq_ring;
259	unsigned tail, next_tail;
260
261	fio_ro_check(td, io_u);
262
263	if (ld->queued == td->o.iodepth)
264	return FIO_Q_BUSY;
265
266	/*
267	* fsync is tricky, since it can fail and we need to do it
268	* serialized with other io. the reason is that linux doesn't
269	* support aio fsync yet. So return busy for the case where we
270	* have pending io, to let fio complete those first.
271	*/
272	if (ddir_sync(io_u->ddir)) {
273	if (ld->queued)
274	return FIO_Q_BUSY;
275
276	do_io_u_sync(td, io_u);
277	return FIO_Q_COMPLETED;
278	}
279
280	if (io_u->ddir == DDIR_TRIM) {
281	if (ld->queued)
282	return FIO_Q_BUSY;
283
284	do_io_u_trim(td, io_u);
285	io_u_mark_submit(td, 1);
286	io_u_mark_complete(td, 1);
287	return FIO_Q_COMPLETED;
288	}
289
290	tail = ring->tail;
291	next_tail = tail + 1;
292	if (next_tail == ring->nr_events)
293	next_tail = 0;
294	read_barrier();
295	if (next_tail == ring->head)
296	return FIO_Q_BUSY;
297
298	ring->array[tail] = io_u->index;
299	ring->tail = next_tail;
300	write_barrier();
301
302	ld->queued++;
303	return FIO_Q_QUEUED;
304	}
305
306	static void fio_aioring_queued(struct thread_data *td, int start, int nr)
307	{
308	struct aioring_data *ld = td->io_ops_data;
309	struct timespec now;
310
311	if (!fio_fill_issue_time(td))
312	return;
313
314	fio_gettime(&now, NULL);
315
316	while (nr--) {
317	int index = ld->sq_ring->array[start];
318	struct io_u *io_u = io_u = ld->io_u_index[index];
319
320	memcpy(&io_u->issue_time, &now, sizeof(now));
321	io_u_queued(td, io_u);
322
323	start++;
324	if (start == ld->sq_ring->nr_events)
325	start = 0;
326	}
327	}
328
329	static int fio_aioring_commit(struct thread_data *td)
330	{
331	struct aioring_data *ld = td->io_ops_data;
332	int ret;
333
334	if (!ld->queued)
335	return 0;
336
337	do {
338	int start = ld->sq_ring->head;
339	long nr = ld->queued;
340
341	ret = io_ring_enter(ld->aio_ctx, nr, 0, IORING_FLAG_SUBMIT \|
342	IORING_FLAG_GETEVENTS);
343	if (ret == -1)
344	perror("io_ring_enter");
345	if (ret > 0) {
346	fio_aioring_queued(td, start, ret);
347	io_u_mark_submit(td, ret);
348
349	ld->queued -= ret;
350	ret = 0;
351	} else if (ret == -EINTR \|\| !ret) {
352	if (!ret)
353	io_u_mark_submit(td, ret);
354	continue;
355	} else if (ret == -EAGAIN) {
356	/*
357	* If we get EAGAIN, we should break out without
358	* error and let the upper layer reap some
359	* events for us. If we have no queued IO, we
360	* must loop here. If we loop for more than 30s,
361	* just error out, something must be buggy in the
362	* IO path.
363	*/
364	if (ld->queued) {
365	ret = 0;
366	break;
367	}
368	usleep(1);
369	continue;
370	} else if (ret == -ENOMEM) {
371	/*
372	* If we get -ENOMEM, reap events if we can. If
373	* we cannot, treat it as a fatal event since there's
374	* nothing we can do about it.
375	*/
376	if (ld->queued)
377	ret = 0;
378	break;
379	} else
380	break;
381	} while (ld->queued);
382
383	return ret;
384	}
385
386	static size_t aioring_cq_size(struct thread_data *td)
387	{
388	return sizeof(struct aio_cq_ring) + 2 * td->o.iodepth * sizeof(struct io_event);
389	}
390
391	static size_t aioring_sq_iocb(struct thread_data *td)
392	{
393	return sizeof(struct iocb) * td->o.iodepth;
394	}
395
396	static size_t aioring_sq_size(struct thread_data *td)
397	{
398	return sizeof(struct aio_sq_ring) + td->o.iodepth * sizeof(u32);
399	}
400
401	static void fio_aioring_cleanup(struct thread_data *td)
402	{
403	struct aioring_data *ld = td->io_ops_data;
404
405	if (ld) {
406	/*
407	* Work-around to avoid huge RCU stalls at exit time. If we
408	* don't do this here, then it'll be torn down by exit_aio().
409	* But for that case we can parallellize the freeing, thus
410	* speeding it up a lot.
411	*/
412	if (!(td->flags & TD_F_CHILD))
413	io_destroy(ld->aio_ctx);
414	free(ld->io_u_index);
415	free(ld->io_us);
416	fio_memfree(ld->sq_ring, aioring_sq_size(td), false);
417	fio_memfree(ld->iocbs, aioring_sq_iocb(td), false);
418	fio_memfree(ld->cq_ring, aioring_cq_size(td), false);
419	free(ld);
420	}
421	}
422
423	static int fio_aioring_queue_init(struct thread_data *td)
424	{
425	#ifdef __NR_sys_io_setup2
426	struct aioring_data *ld = td->io_ops_data;
427	struct aioring_options *o = td->eo;
428	int flags = IOCTX_FLAG_SCQRING;
429	int depth = td->o.iodepth;
430
431	if (o->hipri)
432	flags \|= IOCTX_FLAG_IOPOLL;
433	if (o->fixedbufs) {
434	struct rlimit rlim = {
435	.rlim_cur = RLIM_INFINITY,
436	.rlim_max = RLIM_INFINITY,
437	};
438
439	setrlimit(RLIMIT_MEMLOCK, &rlim);
440	flags \|= IOCTX_FLAG_FIXEDBUFS;
441	}
442
443	return syscall(__NR_sys_io_setup2, depth, flags,
444	ld->sq_ring, ld->cq_ring, &ld->aio_ctx);
445	#else
446	return -1;
447	#endif
448	}
449
450	static int fio_aioring_post_init(struct thread_data *td)
451	{
452	struct aioring_data *ld = td->io_ops_data;
453	struct aioring_options *o = td->eo;
454	struct io_u *io_u;
455	struct iocb *iocb;
456	int err = 0;
457
458	if (o->fixedbufs) {
459	int i;
460
461	for (i = 0; i < td->o.iodepth; i++) {
462	io_u = ld->io_u_index[i];
463	iocb = &ld->iocbs[i];
464	iocb->u.c.buf = io_u->buf;
465	iocb->u.c.nbytes = td_max_bs(td);
466
467	if (o->hipri)
468	iocb->u.c.flags \|= IOCB_FLAG_HIPRI;
469	}
470	}
471
472	err = fio_aioring_queue_init(td);
473	if (err) {
474	td_verror(td, -err, "io_queue_init");
475	return 1;
476	}
477
478	return 0;
479	}
480
481	static int fio_aioring_init(struct thread_data *td)
482	{
483	struct aioring_data *ld;
484
485	if (td->o.iodepth <= 1) {
486	printf("aio-ring: needs a minimum QD of 2\n");
487	return 1;
488	}
489
490	ld = calloc(1, sizeof(*ld));
491
492	/* io_u index */
493	ld->io_u_index = calloc(td->o.iodepth, sizeof(struct io_u *));
494	ld->io_us = calloc(td->o.iodepth, sizeof(struct io_u *));
495
496	ld->iocbs = fio_memalign(page_size, aioring_sq_iocb(td), false);
497	memset(ld->iocbs, 0, aioring_sq_iocb(td));
498
499	ld->sq_ring = fio_memalign(page_size, aioring_sq_size(td), false);
500	memset(ld->sq_ring, 0, aioring_sq_size(td));
501	ld->sq_ring->nr_events = td->o.iodepth;
1f90e9bb	502	ld->sq_ring->iocbs = (u64) (uintptr_t) ld->iocbs;
52885fa2 JA	503
	504	ld->cq_ring = fio_memalign(page_size, aioring_cq_size(td), false);
	505	memset(ld->cq_ring, 0, aioring_cq_size(td));
	506	ld->cq_ring->nr_events = td->o.iodepth * 2;
	507
	508	td->io_ops_data = ld;
	509	return 0;
	510	}
	511
	512	static int fio_aioring_io_u_init(struct thread_data td, struct io_u io_u)
	513	{
	514	struct aioring_data *ld = td->io_ops_data;
	515
	516	ld->io_u_index[io_u->index] = io_u;
	517	return 0;
	518	}
	519
	520	static struct ioengine_ops ioengine = {
	521	.name = "aio-ring",
	522	.version = FIO_IOOPS_VERSION,
	523	.init = fio_aioring_init,
	524	.post_init = fio_aioring_post_init,
	525	.io_u_init = fio_aioring_io_u_init,
	526	.prep = fio_aioring_prep,
	527	.queue = fio_aioring_queue,
	528	.commit = fio_aioring_commit,
	529	.getevents = fio_aioring_getevents,
	530	.event = fio_aioring_event,
	531	.cleanup = fio_aioring_cleanup,
	532	.open_file = generic_open_file,
	533	.close_file = generic_close_file,
	534	.get_file_size = generic_get_file_size,
	535	.options = options,
	536	.option_struct_size = sizeof(struct aioring_options),
	537	};
	538
	539	static void fio_init fio_aioring_register(void)
	540	{
52885fa2	541	register_ioengine(&ioengine);
52885fa2 JA	542	}
	543
	544	static void fio_exit fio_aioring_unregister(void)
	545	{
52885fa2	546	unregister_ioengine(&ioengine);
52885fa2	547	}
1f90e9bb	548	#endif