engines/libaio: remove remnants of abandoned aio features
[fio.git] / engines / libaio.c
CommitLineData
2866c82d 1/*
da751ca9
JA
2 * libaio engine
3 *
4 * IO engine using the Linux native aio interface.
2866c82d
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5 *
6 */
2866c82d
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7#include <stdlib.h>
8#include <unistd.h>
9#include <errno.h>
67bf9823 10#include <libaio.h>
46961748
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11#include <sys/time.h>
12#include <sys/resource.h>
5f350952
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13
14#include "../fio.h"
0f38bbef 15#include "../lib/pow2.h"
d220c761 16#include "../optgroup.h"
90a8c9b2 17#include "../lib/memalign.h"
2866c82d 18
0fc2e103
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19static int fio_libaio_commit(struct thread_data *td);
20
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21struct libaio_data {
22 io_context_t aio_ctx;
23 struct io_event *aio_events;
755200a3 24 struct iocb **iocbs;
7e77dd02 25 struct io_u **io_us;
acd45e02 26
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27 struct io_u **io_u_index;
28
acd45e02
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29 /*
30 * Basic ring buffer. 'head' is incremented in _queue(), and
31 * 'tail' is incremented in _commit(). We keep 'queued' so
32 * that we know if the ring is full or empty, when
33 * 'head' == 'tail'. 'entries' is the ring size, and
34 * 'is_pow2' is just an optimization to use AND instead of
35 * modulus to get the remainder on ring increment.
36 */
37 int is_pow2;
38 unsigned int entries;
39 unsigned int queued;
40 unsigned int head;
41 unsigned int tail;
2866c82d
JA
42};
43
de890a1e 44struct libaio_options {
a1f871c7 45 void *pad;
de890a1e 46 unsigned int userspace_reap;
a391d73d 47 unsigned int hipri;
de890a1e
SL
48};
49
50static struct fio_option options[] = {
51 {
52 .name = "userspace_reap",
e8b0e958 53 .lname = "Libaio userspace reaping",
de890a1e
SL
54 .type = FIO_OPT_STR_SET,
55 .off1 = offsetof(struct libaio_options, userspace_reap),
56 .help = "Use alternative user-space reap implementation",
e90a0adf 57 .category = FIO_OPT_C_ENGINE,
5a3cd5f3 58 .group = FIO_OPT_G_LIBAIO,
de890a1e
SL
59 },
60 {
61 .name = NULL,
62 },
63};
64
acd45e02
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65static inline void ring_inc(struct libaio_data *ld, unsigned int *val,
66 unsigned int add)
67{
68 if (ld->is_pow2)
69 *val = (*val + add) & (ld->entries - 1);
70 else
71 *val = (*val + add) % ld->entries;
72}
73
7a16dd02 74static int fio_libaio_prep(struct thread_data fio_unused *td, struct io_u *io_u)
2866c82d 75{
53cdc686 76 struct fio_file *f = io_u->file;
ad4e9298 77 struct iocb *iocb = &io_u->iocb;
53cdc686 78
a391d73d 79 if (io_u->ddir == DDIR_READ) {
702906e9 80 io_prep_pread(iocb, f->fd, io_u->xfer_buf, io_u->xfer_buflen, io_u->offset);
a391d73d 81 } else if (io_u->ddir == DDIR_WRITE) {
702906e9 82 io_prep_pwrite(iocb, f->fd, io_u->xfer_buf, io_u->xfer_buflen, io_u->offset);
a391d73d 83 } else if (ddir_sync(io_u->ddir))
3c3168e9 84 io_prep_fsync(iocb, f->fd);
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85
86 return 0;
87}
88
89static struct io_u *fio_libaio_event(struct thread_data *td, int event)
90{
565e784d 91 struct libaio_data *ld = td->io_ops_data;
f423479d
JA
92 struct io_event *ev;
93 struct io_u *io_u;
2866c82d 94
f423479d 95 ev = ld->aio_events + event;
702906e9 96 io_u = container_of(ev->obj, struct io_u, iocb);
f423479d
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97
98 if (ev->res != io_u->xfer_buflen) {
99 if (ev->res > io_u->xfer_buflen)
100 io_u->error = -ev->res;
101 else
102 io_u->resid = io_u->xfer_buflen - ev->res;
103 } else
104 io_u->error = 0;
105
106 return io_u;
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107}
108
675012f0
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109struct aio_ring {
110 unsigned id; /** kernel internal index number */
111 unsigned nr; /** number of io_events */
112 unsigned head;
113 unsigned tail;
c44b1ff5 114
675012f0
DE
115 unsigned magic;
116 unsigned compat_features;
117 unsigned incompat_features;
118 unsigned header_length; /** size of aio_ring */
119
120 struct io_event events[0];
121};
122
123#define AIO_RING_MAGIC 0xa10a10a1
124
125static int user_io_getevents(io_context_t aio_ctx, unsigned int max,
c44b1ff5 126 struct io_event *events)
675012f0
DE
127{
128 long i = 0;
129 unsigned head;
c44b1ff5 130 struct aio_ring *ring = (struct aio_ring*) aio_ctx;
675012f0
DE
131
132 while (i < max) {
133 head = ring->head;
134
135 if (head == ring->tail) {
136 /* There are no more completions */
137 break;
138 } else {
139 /* There is another completion to reap */
140 events[i] = ring->events[head];
141 read_barrier();
c44b1ff5 142 ring->head = (head + 1) % ring->nr;
675012f0
DE
143 i++;
144 }
145 }
146
147 return i;
148}
149
e7d2e616 150static int fio_libaio_getevents(struct thread_data *td, unsigned int min,
1f440ece 151 unsigned int max, const struct timespec *t)
2866c82d 152{
565e784d 153 struct libaio_data *ld = td->io_ops_data;
de890a1e 154 struct libaio_options *o = td->eo;
82407585 155 unsigned actual_min = td->o.iodepth_batch_complete_min == 0 ? 0 : min;
1f440ece 156 struct timespec __lt, *lt = NULL;
0b7fdba7 157 int r, events = 0;
2866c82d 158
1f440ece
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159 if (t) {
160 __lt = *t;
161 lt = &__lt;
162 }
163
2866c82d 164 do {
de890a1e 165 if (o->userspace_reap == 1
675012f0
DE
166 && actual_min == 0
167 && ((struct aio_ring *)(ld->aio_ctx))->magic
168 == AIO_RING_MAGIC) {
169 r = user_io_getevents(ld->aio_ctx, max,
170 ld->aio_events + events);
171 } else {
172 r = io_getevents(ld->aio_ctx, actual_min,
1f440ece 173 max, ld->aio_events + events, lt);
675012f0 174 }
3441a52d 175 if (r > 0)
0b7fdba7 176 events += r;
3441a52d 177 else if ((min && r == 0) || r == -EAGAIN) {
0fc2e103 178 fio_libaio_commit(td);
6347e43d
JA
179 if (actual_min)
180 usleep(10);
0fc2e103 181 } else if (r != -EINTR)
a31dc2dd 182 break;
0b7fdba7
DE
183 } while (events < min);
184
185 return r < 0 ? r : events;
2866c82d
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186}
187
2e4ef4fb
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188static enum fio_q_status fio_libaio_queue(struct thread_data *td,
189 struct io_u *io_u)
2866c82d 190{
565e784d 191 struct libaio_data *ld = td->io_ops_data;
2866c82d 192
7101d9c2
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193 fio_ro_check(td, io_u);
194
acd45e02 195 if (ld->queued == td->o.iodepth)
755200a3
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196 return FIO_Q_BUSY;
197
198 /*
199 * fsync is tricky, since it can fail and we need to do it
200 * serialized with other io. the reason is that linux doesn't
201 * support aio fsync yet. So return busy for the case where we
202 * have pending io, to let fio complete those first.
203 */
f011531e 204 if (ddir_sync(io_u->ddir)) {
acd45e02 205 if (ld->queued)
755200a3 206 return FIO_Q_BUSY;
5f9099ea 207
f011531e 208 do_io_u_sync(td, io_u);
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209 return FIO_Q_COMPLETED;
210 }
211
a5f3027c 212 if (io_u->ddir == DDIR_TRIM) {
acd45e02 213 if (ld->queued)
a5f3027c
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214 return FIO_Q_BUSY;
215
216 do_io_u_trim(td, io_u);
c0681c9d
VF
217 io_u_mark_submit(td, 1);
218 io_u_mark_complete(td, 1);
a5f3027c
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219 return FIO_Q_COMPLETED;
220 }
221
702906e9 222 ld->iocbs[ld->head] = &io_u->iocb;
acd45e02
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223 ld->io_us[ld->head] = io_u;
224 ring_inc(ld, &ld->head, 1);
225 ld->queued++;
755200a3
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226 return FIO_Q_QUEUED;
227}
228
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229static void fio_libaio_queued(struct thread_data *td, struct io_u **io_us,
230 unsigned int nr)
231{
8b6a404c 232 struct timespec now;
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233 unsigned int i;
234
12d9d841
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235 if (!fio_fill_issue_time(td))
236 return;
237
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238 fio_gettime(&now, NULL);
239
240 for (i = 0; i < nr; i++) {
241 struct io_u *io_u = io_us[i];
242
243 memcpy(&io_u->issue_time, &now, sizeof(now));
244 io_u_queued(td, io_u);
245 }
246}
247
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248static int fio_libaio_commit(struct thread_data *td)
249{
565e784d 250 struct libaio_data *ld = td->io_ops_data;
755200a3 251 struct iocb **iocbs;
7e77dd02 252 struct io_u **io_us;
8b6a404c 253 struct timespec ts;
a120ca7f 254 int ret, wait_start = 0;
755200a3 255
acd45e02 256 if (!ld->queued)
755200a3
JA
257 return 0;
258
2866c82d 259 do {
acd45e02
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260 long nr = ld->queued;
261
262 nr = min((unsigned int) nr, ld->entries - ld->tail);
263 io_us = ld->io_us + ld->tail;
264 iocbs = ld->iocbs + ld->tail;
265
266 ret = io_submit(ld->aio_ctx, nr, iocbs);
5e00c2c4 267 if (ret > 0) {
7e77dd02 268 fio_libaio_queued(td, io_us, ret);
838bc709 269 io_u_mark_submit(td, ret);
acd45e02
JA
270
271 ld->queued -= ret;
272 ring_inc(ld, &ld->tail, ret);
5e00c2c4 273 ret = 0;
e3b4e568 274 wait_start = 0;
acd45e02 275 } else if (ret == -EINTR || !ret) {
838bc709
JA
276 if (!ret)
277 io_u_mark_submit(td, ret);
e3b4e568 278 wait_start = 0;
2866c82d 279 continue;
acd45e02
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280 } else if (ret == -EAGAIN) {
281 /*
282 * If we get EAGAIN, we should break out without
283 * error and let the upper layer reap some
a120ca7f
JA
284 * events for us. If we have no queued IO, we
285 * must loop here. If we loop for more than 30s,
286 * just error out, something must be buggy in the
287 * IO path.
acd45e02 288 */
a120ca7f
JA
289 if (ld->queued) {
290 ret = 0;
291 break;
292 }
293 if (!wait_start) {
8b6a404c 294 fio_gettime(&ts, NULL);
d36b072d 295 wait_start = 1;
8b6a404c 296 } else if (mtime_since_now(&ts) > 30000) {
a120ca7f
JA
297 log_err("fio: aio appears to be stalled, giving up\n");
298 break;
299 }
300 usleep(1);
301 continue;
a31dc2dd
JA
302 } else if (ret == -ENOMEM) {
303 /*
304 * If we get -ENOMEM, reap events if we can. If
305 * we cannot, treat it as a fatal event since there's
306 * nothing we can do about it.
307 */
308 if (ld->queued)
309 ret = 0;
310 break;
838bc709 311 } else
2866c82d 312 break;
2c3a4ae9 313 } while (ld->queued);
2866c82d 314
36167d82 315 return ret;
2866c82d
JA
316}
317
318static int fio_libaio_cancel(struct thread_data *td, struct io_u *io_u)
319{
565e784d 320 struct libaio_data *ld = td->io_ops_data;
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JA
321
322 return io_cancel(ld->aio_ctx, &io_u->iocb, ld->aio_events);
323}
324
325static void fio_libaio_cleanup(struct thread_data *td)
326{
565e784d 327 struct libaio_data *ld = td->io_ops_data;
2866c82d
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328
329 if (ld) {
f24c2649
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330 /*
331 * Work-around to avoid huge RCU stalls at exit time. If we
332 * don't do this here, then it'll be torn down by exit_aio().
333 * But for that case we can parallellize the freeing, thus
334 * speeding it up a lot.
335 */
336 if (!(td->flags & TD_F_CHILD))
337 io_destroy(ld->aio_ctx);
7e77dd02
JA
338 free(ld->aio_events);
339 free(ld->iocbs);
340 free(ld->io_us);
2866c82d 341 free(ld);
2866c82d
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342 }
343}
344
2041bd34
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345static int fio_libaio_post_init(struct thread_data *td)
346{
347 struct libaio_data *ld = td->io_ops_data;
ad4e9298 348 int err;
2041bd34 349
ad4e9298 350 err = io_queue_init(td->o.iodepth, &ld->aio_ctx);
2041bd34
JA
351 if (err) {
352 td_verror(td, -err, "io_queue_init");
353 return 1;
354 }
355
356 return 0;
ebec344d
JA
357}
358
2866c82d
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359static int fio_libaio_init(struct thread_data *td)
360{
acd45e02 361 struct libaio_data *ld;
2866c82d 362
acd45e02 363 ld = calloc(1, sizeof(*ld));
c1db2dce 364
acd45e02
JA
365 ld->entries = td->o.iodepth;
366 ld->is_pow2 = is_power_of_2(ld->entries);
367 ld->aio_events = calloc(ld->entries, sizeof(struct io_event));
368 ld->iocbs = calloc(ld->entries, sizeof(struct iocb *));
369 ld->io_us = calloc(ld->entries, sizeof(struct io_u *));
755200a3 370
565e784d 371 td->io_ops_data = ld;
2866c82d
JA
372 return 0;
373}
374
5f350952 375static struct ioengine_ops ioengine = {
de890a1e
SL
376 .name = "libaio",
377 .version = FIO_IOOPS_VERSION,
04ba61df 378 .flags = FIO_ASYNCIO_SYNC_TRIM,
de890a1e 379 .init = fio_libaio_init,
2041bd34 380 .post_init = fio_libaio_post_init,
de890a1e
SL
381 .prep = fio_libaio_prep,
382 .queue = fio_libaio_queue,
383 .commit = fio_libaio_commit,
384 .cancel = fio_libaio_cancel,
385 .getevents = fio_libaio_getevents,
386 .event = fio_libaio_event,
387 .cleanup = fio_libaio_cleanup,
388 .open_file = generic_open_file,
389 .close_file = generic_close_file,
390 .get_file_size = generic_get_file_size,
391 .options = options,
392 .option_struct_size = sizeof(struct libaio_options),
2866c82d 393};
34cfcdaf 394
5f350952
JA
395static void fio_init fio_libaio_register(void)
396{
397 register_ioengine(&ioengine);
398}
399
400static void fio_exit fio_libaio_unregister(void)
401{
402 unregister_ioengine(&ioengine);
403}