zbd: Declare local functions 'static'
[fio.git] / ioengines.c
CommitLineData
ebac4655
JA
1/*
2 * The io parts of the fio tool, includes workers for sync and mmap'ed
3 * io, as well as both posix and linux libaio support.
4 *
5 * sync io is implemented on top of aio.
6 *
7 * This is not really specific to fio, if the get_io_u/put_io_u and
8 * structures was pulled into this as well it would be a perfectly
9 * generic io engine that could be used for other projects.
10 *
11 */
ebac4655
JA
12#include <stdlib.h>
13#include <unistd.h>
5c4e1dbc 14#include <string.h>
2866c82d 15#include <dlfcn.h>
ecc314ba 16#include <fcntl.h>
0c6e7517 17#include <assert.h>
8c16d840 18
ebac4655 19#include "fio.h"
7c9b1bce 20#include "diskutil.h"
bfbdd35b 21#include "zbd.h"
ebac4655 22
01743ee1 23static FLIST_HEAD(engine_list);
5f350952 24
1cc954ba 25static bool check_engine_ops(struct ioengine_ops *ops)
8c16d840 26{
5f350952 27 if (ops->version != FIO_IOOPS_VERSION) {
5ec10eaa
JA
28 log_err("bad ioops version %d (want %d)\n", ops->version,
29 FIO_IOOPS_VERSION);
1cc954ba 30 return true;
5f350952
JA
31 }
32
36167d82
JA
33 if (!ops->queue) {
34 log_err("%s: no queue handler\n", ops->name);
1cc954ba 35 return true;
36167d82
JA
36 }
37
38 /*
39 * sync engines only need a ->queue()
40 */
41 if (ops->flags & FIO_SYNCIO)
1cc954ba 42 return false;
5ec10eaa 43
1cc954ba
JA
44 if (!ops->event || !ops->getevents) {
45 log_err("%s: no event/getevents handler\n", ops->name);
46 return true;
8c16d840 47 }
5ec10eaa 48
1cc954ba 49 return false;
8c16d840
JA
50}
51
5f350952 52void unregister_ioengine(struct ioengine_ops *ops)
ebac4655 53{
ee56ad50 54 dprint(FD_IO, "ioengine %s unregistered\n", ops->name);
adf075fa 55 flist_del_init(&ops->list);
5f350952
JA
56}
57
b2fdda43 58void register_ioengine(struct ioengine_ops *ops)
5f350952 59{
ee56ad50 60 dprint(FD_IO, "ioengine %s registered\n", ops->name);
01743ee1 61 flist_add_tail(&ops->list, &engine_list);
5f350952
JA
62}
63
64static struct ioengine_ops *find_ioengine(const char *name)
65{
66 struct ioengine_ops *ops;
01743ee1 67 struct flist_head *entry;
ebac4655 68
01743ee1
JA
69 flist_for_each(entry, &engine_list) {
70 ops = flist_entry(entry, struct ioengine_ops, list);
bc5b77a8 71 if (!strcmp(name, ops->name))
5f350952
JA
72 return ops;
73 }
74
75 return NULL;
76}
77
78static struct ioengine_ops *dlopen_ioengine(struct thread_data *td,
79 const char *engine_lib)
80{
81 struct ioengine_ops *ops;
82 void *dlhandle;
83
ee56ad50
JA
84 dprint(FD_IO, "dload engine %s\n", engine_lib);
85
2866c82d
JA
86 dlerror();
87 dlhandle = dlopen(engine_lib, RTLD_LAZY);
d4dbaaa8 88 if (!dlhandle) {
e1161c32 89 td_vmsg(td, -1, dlerror(), "dlopen");
d4dbaaa8
JA
90 return NULL;
91 }
8756e4d4 92
da51c050
JA
93 /*
94 * Unlike the included modules, external engines should have a
95 * non-static ioengine structure that we can reference.
96 */
0abea0b7
DM
97 ops = dlsym(dlhandle, engine_lib);
98 if (!ops)
99 ops = dlsym(dlhandle, "ioengine");
a8075704
DG
100
101 /*
102 * For some external engines (like C++ ones) it is not that trivial
103 * to provide a non-static ionengine structure that we can reference.
104 * Instead we call a method which allocates the required ioengine
105 * structure.
106 */
107 if (!ops) {
108 get_ioengine_t get_ioengine = dlsym(dlhandle, "get_ioengine");
109
110 if (get_ioengine)
111 get_ioengine(&ops);
112 }
113
d4dbaaa8 114 if (!ops) {
e1161c32 115 td_vmsg(td, -1, dlerror(), "dlsym");
d4dbaaa8
JA
116 dlclose(dlhandle);
117 return NULL;
118 }
8756e4d4 119
565e784d 120 td->io_ops_dlhandle = dlhandle;
5f350952
JA
121 return ops;
122}
123
97bb54c9
TK
124static struct ioengine_ops *__load_ioengine(const char *name)
125{
126 char engine[64];
127
128 engine[sizeof(engine) - 1] = '\0';
129 strncpy(engine, name, sizeof(engine) - 1);
130
131 /*
132 * linux libaio has alias names, so convert to what we want
133 */
59cd9313 134 if (!strncmp(engine, "linuxaio", 8)) {
966fcbd4 135 dprint(FD_IO, "converting ioengine name: %s -> libaio\n", name);
97bb54c9 136 strcpy(engine, "libaio");
966fcbd4 137 }
97bb54c9
TK
138
139 dprint(FD_IO, "load ioengine %s\n", engine);
140 return find_ioengine(engine);
141}
142
4fedf59a 143struct ioengine_ops *load_ioengine(struct thread_data *td)
5f350952 144{
81647a9a 145 struct ioengine_ops *ops = NULL;
ba872a0b 146 const char *name;
81647a9a 147
ba872a0b
TK
148 /*
149 * Use ->ioengine_so_path if an external ioengine path is specified.
150 * In this case, ->ioengine is "external" which also means the prefix
151 * for external ioengines "external:" is properly used.
152 */
153 name = td->o.ioengine_so_path ?: td->o.ioengine;
154
155 /*
156 * Try to load ->ioengine first, and if failed try to dlopen(3) either
157 * ->ioengine or ->ioengine_so_path. This is redundant for an external
158 * ioengine with prefix, and also leaves the possibility of unexpected
159 * behavior (e.g. if the "external" ioengine exists), but we do this
160 * so as not to break job files not using the prefix.
161 */
162 ops = __load_ioengine(td->o.ioengine);
163 if (!ops)
5f350952
JA
164 ops = dlopen_ioengine(td, name);
165
ba872a0b
TK
166 /*
167 * If ops is NULL, we failed to load ->ioengine, and also failed to
168 * dlopen(3) either ->ioengine or ->ioengine_so_path as a path.
169 */
5f350952
JA
170 if (!ops) {
171 log_err("fio: engine %s not loadable\n", name);
b902ceb5
JA
172 return NULL;
173 }
174
8c16d840
JA
175 /*
176 * Check that the required methods are there.
177 */
5f350952 178 if (check_engine_ops(ops))
8c16d840 179 return NULL;
8c16d840 180
565e784d 181 return ops;
8756e4d4
JA
182}
183
de890a1e
SL
184/*
185 * For cleaning up an ioengine which never made it to init().
186 */
187void free_ioengine(struct thread_data *td)
8756e4d4 188{
de890a1e 189 dprint(FD_IO, "free ioengine %s\n", td->io_ops->name);
ee56ad50 190
de890a1e
SL
191 if (td->eo && td->io_ops->options) {
192 options_free(td->io_ops->options, td->eo);
193 free(td->eo);
194 td->eo = NULL;
2992b059 195 }
b990b5c0 196
9b50942e 197 if (td->io_ops_dlhandle) {
565e784d 198 dlclose(td->io_ops_dlhandle);
9b50942e
JA
199 td->io_ops_dlhandle = NULL;
200 }
5f350952 201
84585003 202 td->io_ops = NULL;
b990b5c0 203}
10ba535a 204
de890a1e
SL
205void close_ioengine(struct thread_data *td)
206{
207 dprint(FD_IO, "close ioengine %s\n", td->io_ops->name);
208
209 if (td->io_ops->cleanup) {
210 td->io_ops->cleanup(td);
565e784d 211 td->io_ops_data = NULL;
de890a1e
SL
212 }
213
214 free_ioengine(td);
215}
216
10ba535a
JA
217int td_io_prep(struct thread_data *td, struct io_u *io_u)
218{
ee56ad50 219 dprint_io_u(io_u, "prep");
7101d9c2
JA
220 fio_ro_check(td, io_u);
221
4d4e80f2 222 lock_file(td, io_u->file, io_u->ddir);
b2bd2bd9 223
2ba1c290
JA
224 if (td->io_ops->prep) {
225 int ret = td->io_ops->prep(td, io_u);
226
e5f9a813
RE
227 dprint(FD_IO, "prep: io_u %p: ret=%d\n", io_u, ret);
228
b2bd2bd9 229 if (ret)
4d4e80f2 230 unlock_file(td, io_u->file);
2ba1c290
JA
231 return ret;
232 }
10ba535a
JA
233
234 return 0;
235}
236
e7d2e616 237int td_io_getevents(struct thread_data *td, unsigned int min, unsigned int max,
1f440ece 238 const struct timespec *t)
10ba535a 239{
ee56ad50 240 int r = 0;
face81b2 241
a05d62b2
YR
242 /*
243 * For ioengine=rdma one side operation RDMA_WRITE or RDMA_READ,
244 * server side gets a message from the client
245 * side that the task is finished, and
246 * td->done is set to 1 after td_io_commit(). In this case,
247 * there is no need to reap complete event in server side.
248 */
249 if (td->done)
250 return 0;
251
ee56ad50
JA
252 if (min > 0 && td->io_ops->commit) {
253 r = td->io_ops->commit(td);
face81b2 254 if (r < 0)
ee56ad50 255 goto out;
face81b2 256 }
4950421a
JA
257 if (max > td->cur_depth)
258 max = td->cur_depth;
259 if (min > max)
260 max = min;
36167d82 261
ee56ad50 262 r = 0;
4950421a 263 if (max && td->io_ops->getevents)
ee56ad50
JA
264 r = td->io_ops->getevents(td, min, max, t);
265out:
422f9e4b
RM
266 if (r >= 0) {
267 /*
3fd9efbc 268 * Reflect that our submitted requests were retrieved with
422f9e4b
RM
269 * whatever OS async calls are in the underlying engine.
270 */
271 td->io_u_in_flight -= r;
838bc709 272 io_u_mark_complete(td, r);
422f9e4b 273 } else
7c639b14 274 td_verror(td, r, "get_events");
f3e11d05 275
ee56ad50
JA
276 dprint(FD_IO, "getevents: %d\n", r);
277 return r;
10ba535a
JA
278}
279
d3b07186 280enum fio_q_status td_io_queue(struct thread_data *td, struct io_u *io_u)
10ba535a 281{
a9da8ab2 282 const enum fio_ddir ddir = acct_ddir(io_u);
5fff9543 283 unsigned long long buflen = io_u->xfer_buflen;
d3b07186 284 enum fio_q_status ret;
7e77dd02 285
ee56ad50 286 dprint_io_u(io_u, "queue");
7101d9c2
JA
287 fio_ro_check(td, io_u);
288
0c6e7517 289 assert((io_u->flags & IO_U_F_FLIGHT) == 0);
1651e431 290 io_u_set(td, io_u, IO_U_F_FLIGHT);
817ae977
VF
291
292 /*
293 * If overlap checking was enabled in offload mode we
294 * can release this lock that was acquired when we
295 * started the overlap check because the IO_U_F_FLIGHT
296 * flag is now set
297 */
1368d95b 298 if (td_offload_overlap(td))
c06379a6 299 pthread_mutex_unlock(&overlap_check);
0c6e7517 300
d6aed795 301 assert(fio_file_open(io_u->file));
3d7b485f 302
bcd5abfa
JA
303 /*
304 * If using a write iolog, store this entry.
305 */
306 log_io_u(td, io_u);
307
11786802
JA
308 io_u->error = 0;
309 io_u->resid = 0;
310
04ba61df
VF
311 if (td_ioengine_flagged(td, FIO_SYNCIO) ||
312 (td_ioengine_flagged(td, FIO_ASYNCIO_SYNC_TRIM) &&
313 io_u->ddir == DDIR_TRIM)) {
12d9d841 314 if (fio_fill_issue_time(td))
9520ebb9 315 fio_gettime(&io_u->issue_time, NULL);
d0c15328
JA
316
317 /*
318 * only used for iolog
319 */
320 if (td->o.read_iolog_file)
321 memcpy(&td->last_issue, &io_u->issue_time,
8b6a404c 322 sizeof(io_u->issue_time));
433afcb4
JA
323 }
324
a9da8ab2 325 if (ddir_rw(ddir)) {
a7d01f02
JA
326 if (!(io_u->flags & IO_U_F_VER_LIST)) {
327 td->io_issues[ddir]++;
328 td->io_issue_bytes[ddir] += buflen;
329 }
50a8ce86 330 td->rate_io_issue_bytes[ddir] += buflen;
74d6277f 331 }
755200a3 332
7e77dd02 333 ret = td->io_ops->queue(td, io_u);
d9ed3e63 334 zbd_queue_io_u(io_u, ret);
5aeb77df 335
4d4e80f2 336 unlock_file(td, io_u->file);
b2bd2bd9 337
a9da8ab2
JA
338 if (ret == FIO_Q_BUSY && ddir_rw(ddir)) {
339 td->io_issues[ddir]--;
340 td->io_issue_bytes[ddir] -= buflen;
50a8ce86 341 td->rate_io_issue_bytes[ddir] -= buflen;
871467d9 342 io_u_clear(td, io_u, IO_U_F_FLIGHT);
cd8a19e6
JA
343 }
344
39a43d34
JA
345 /*
346 * If an error was seen and the io engine didn't propagate it
347 * back to 'td', do so.
348 */
349 if (io_u->error && !td->error)
350 td_verror(td, io_u->error, "td_io_queue");
351
cb211682
JA
352 /*
353 * Add warning for O_DIRECT so that users have an easier time
354 * spotting potentially bad alignment. If this triggers for the first
355 * IO, then it's likely an alignment problem or because the host fs
356 * does not support O_DIRECT
357 */
ff58fced 358 if (io_u->error == EINVAL && td->io_issues[io_u->ddir & 1] == 1 &&
cb211682 359 td->o.odirect) {
214ac7e0 360
cb211682 361 log_info("fio: first direct IO errored. File system may not "
78d4a262
TK
362 "support direct IO, or iomem_align= is bad, or "
363 "invalid block size. Try setting direct=0.\n");
cb211682
JA
364 }
365
bfbdd35b
BVA
366 if (zbd_unaligned_write(io_u->error) &&
367 td->io_issues[io_u->ddir & 1] == 1 &&
368 td->o.zone_mode != ZONE_MODE_ZBD) {
369 log_info("fio: first I/O failed. If %s is a zoned block device, consider --zonemode=zbd\n",
370 io_u->file->file_name);
371 }
372
c0681c9d 373 if (!td->io_ops->commit) {
838bc709
JA
374 io_u_mark_submit(td, 1);
375 io_u_mark_complete(td, 1);
d9ed3e63 376 zbd_put_io_u(io_u);
838bc709
JA
377 }
378
d8005759 379 if (ret == FIO_Q_COMPLETED) {
7f3ecee2 380 if (ddir_rw(io_u->ddir) || ddir_sync(io_u->ddir)) {
d8005759
JA
381 io_u_mark_depth(td, 1);
382 td->ts.total_io_u[io_u->ddir]++;
6eaf09d6 383 }
d8005759 384 } else if (ret == FIO_Q_QUEUED) {
e6727cbd
JA
385 td->io_u_queued++;
386
7f3ecee2 387 if (ddir_rw(io_u->ddir) || ddir_sync(io_u->ddir))
d8005759 388 td->ts.total_io_u[io_u->ddir]++;
d8005759 389
a80cb54b
BVA
390 if (td->io_u_queued >= td->o.iodepth_batch)
391 td_io_commit(td);
eb7c8ae2 392 }
cb5ab512 393
04ba61df
VF
394 if (!td_ioengine_flagged(td, FIO_SYNCIO) &&
395 (!td_ioengine_flagged(td, FIO_ASYNCIO_SYNC_TRIM) ||
396 io_u->ddir != DDIR_TRIM)) {
12d9d841 397 if (fio_fill_issue_time(td))
9520ebb9 398 fio_gettime(&io_u->issue_time, NULL);
d0c15328
JA
399
400 /*
401 * only used for iolog
402 */
403 if (td->o.read_iolog_file)
404 memcpy(&td->last_issue, &io_u->issue_time,
8b6a404c 405 sizeof(io_u->issue_time));
433afcb4
JA
406 }
407
7e77dd02 408 return ret;
10ba535a 409}
8c16d840
JA
410
411int td_io_init(struct thread_data *td)
412{
eeb12160 413 int ret = 0;
8c16d840 414
eeb12160
JA
415 if (td->io_ops->init) {
416 ret = td->io_ops->init(td);
356ef1a1
TK
417 if (ret)
418 log_err("fio: io engine %s init failed.%s\n",
419 td->io_ops->name,
420 td->o.iodepth > 1 ?
421 " Perhaps try reducing io depth?" : "");
422 else
423 td->io_ops_init = 1;
7c973896
JA
424 if (!td->error)
425 td->error = ret;
eeb12160
JA
426 }
427
428 return ret;
8c16d840 429}
755200a3 430
a80cb54b 431void td_io_commit(struct thread_data *td)
755200a3 432{
f3e11d05
JA
433 int ret;
434
ee56ad50
JA
435 dprint(FD_IO, "calling ->commit(), depth %d\n", td->cur_depth);
436
d8005759 437 if (!td->cur_depth || !td->io_u_queued)
a80cb54b 438 return;
cb5ab512 439
3fd9efbc 440 io_u_mark_depth(td, td->io_u_queued);
d8005759 441
f3e11d05
JA
442 if (td->io_ops->commit) {
443 ret = td->io_ops->commit(td);
444 if (ret)
445 td_verror(td, -ret, "io commit");
446 }
3fd9efbc 447
422f9e4b
RM
448 /*
449 * Reflect that events were submitted as async IO requests.
450 */
451 td->io_u_in_flight += td->io_u_queued;
452 td->io_u_queued = 0;
755200a3 453}
b5af8293
JA
454
455int td_io_open_file(struct thread_data *td, struct fio_file *f)
456{
230f33fb
AK
457 if (fio_file_closing(f)) {
458 /*
459 * Open translates to undo closing.
460 */
461 fio_file_clear_closing(f);
462 get_file(f);
463 return 0;
464 }
22a57ba8
JA
465 assert(!fio_file_open(f));
466 assert(f->fd == -1);
966fcbd4 467 assert(td->io_ops->open_file);
22a57ba8 468
413d6693
JA
469 if (td->io_ops->open_file(td, f)) {
470 if (td->error == EINVAL && td->o.odirect)
471 log_err("fio: destination does not support O_DIRECT\n");
5ec10eaa
JA
472 if (td->error == EMFILE) {
473 log_err("fio: try reducing/setting openfiles (failed"
474 " at %u of %u)\n", td->nr_open_files,
475 td->o.nr_files);
476 }
413d6693 477
22a57ba8
JA
478 assert(f->fd == -1);
479 assert(!fio_file_open(f));
413d6693
JA
480 return 1;
481 }
482
33c48814 483 fio_file_reset(td, f);
d6aed795
JA
484 fio_file_set_open(f);
485 fio_file_clear_closing(f);
c97bd0fa 486 disk_util_inc(f->du);
d5707a35
JA
487
488 td->nr_open_files++;
489 get_file(f);
490
66159828
JA
491 if (f->filetype == FIO_TYPE_PIPE) {
492 if (td_random(td)) {
493 log_err("fio: can't seek on pipes (no random io)\n");
494 goto err;
495 }
496 }
497
9b87f09b 498 if (td_ioengine_flagged(td, FIO_DISKLESSIO))
413d6693
JA
499 goto done;
500
501 if (td->o.invalidate_cache && file_invalidate_cache(td, f))
502 goto err;
503
ecb2083d 504 if (td->o.fadvise_hint != F_ADV_NONE &&
686fbd31 505 (f->filetype == FIO_TYPE_BLOCK || f->filetype == FIO_TYPE_FILE)) {
413d6693
JA
506 int flags;
507
ecb2083d
JA
508 if (td->o.fadvise_hint == F_ADV_TYPE) {
509 if (td_random(td))
510 flags = POSIX_FADV_RANDOM;
511 else
512 flags = POSIX_FADV_SEQUENTIAL;
513 } else if (td->o.fadvise_hint == F_ADV_RANDOM)
413d6693 514 flags = POSIX_FADV_RANDOM;
ecb2083d 515 else if (td->o.fadvise_hint == F_ADV_SEQUENTIAL)
413d6693 516 flags = POSIX_FADV_SEQUENTIAL;
ecb2083d
JA
517 else {
518 log_err("fio: unknown fadvise type %d\n",
519 td->o.fadvise_hint);
520 flags = POSIX_FADV_NORMAL;
521 }
413d6693 522
ecc314ba 523 if (posix_fadvise(f->fd, f->file_offset, f->io_size, flags) < 0) {
825b0a75
JA
524 if (!fio_did_warn(FIO_WARN_FADVISE))
525 log_err("fio: fadvise hint failed\n");
413d6693 526 }
7bb48f84 527 }
ae8e559e
JA
528#ifdef FIO_HAVE_WRITE_HINT
529 if (fio_option_is_set(&td->o, write_hint) &&
686fbd31 530 (f->filetype == FIO_TYPE_BLOCK || f->filetype == FIO_TYPE_FILE)) {
ae8e559e 531 uint64_t hint = td->o.write_hint;
bd553af6 532 int cmd;
37659335 533
bd553af6
JA
534 /*
535 * For direct IO, we just need/want to set the hint on
536 * the file descriptor. For buffered IO, we need to set
537 * it on the inode.
538 */
539 if (td->o.odirect)
540 cmd = F_SET_FILE_RW_HINT;
541 else
542 cmd = F_SET_RW_HINT;
543
544 if (fcntl(f->fd, cmd, &hint) < 0) {
ae8e559e 545 td_verror(td, errno, "fcntl write hint");
37659335
JA
546 goto err;
547 }
548 }
549#endif
a978ba68 550
47534cda
TK
551 if (td->o.odirect && !OS_O_DIRECT && fio_set_directio(td, f))
552 goto err;
e116f2b9 553
413d6693 554done:
f29b25a3 555 log_file(td, f, FIO_LOG_OPEN_FILE);
413d6693
JA
556 return 0;
557err:
c97bd0fa 558 disk_util_dec(f->du);
b284075a
JA
559 if (td->io_ops->close_file)
560 td->io_ops->close_file(td, f);
7bb48f84 561 return 1;
b5af8293
JA
562}
563
6977bcd0 564int td_io_close_file(struct thread_data *td, struct fio_file *f)
b5af8293 565{
d6aed795 566 if (!fio_file_closing(f))
f29b25a3
JA
567 log_file(td, f, FIO_LOG_CLOSE_FILE);
568
0ad920e7
JA
569 /*
570 * mark as closing, do real close when last io on it has completed
571 */
d6aed795 572 fio_file_set_closing(f);
0ad920e7 573
6977bcd0 574 return put_file(td, f);
b5af8293 575}
df9c26b1 576
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CF
577int td_io_unlink_file(struct thread_data *td, struct fio_file *f)
578{
579 if (td->io_ops->unlink_file)
580 return td->io_ops->unlink_file(td, f);
2442c935
JA
581 else {
582 int ret;
583
584 ret = unlink(f->file_name);
585 if (ret < 0)
586 return errno;
587
588 return 0;
589 }
38ef9c90
CF
590}
591
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592int td_io_get_file_size(struct thread_data *td, struct fio_file *f)
593{
594 if (!td->io_ops->get_file_size)
595 return 0;
596
597 return td->io_ops->get_file_size(td, f);
598}
44f29692 599
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600int fio_show_ioengine_help(const char *engine)
601{
602 struct flist_head *entry;
d04f1d5b 603 struct thread_data td;
755dcbbd 604 struct ioengine_ops *io_ops;
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605 char *sep;
606 int ret = 1;
607
608 if (!engine || !*engine) {
609 log_info("Available IO engines:\n");
610 flist_for_each(entry, &engine_list) {
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611 io_ops = flist_entry(entry, struct ioengine_ops, list);
612 log_info("\t%s\n", io_ops->name);
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613 }
614 return 0;
615 }
616 sep = strchr(engine, ',');
617 if (sep) {
618 *sep = 0;
619 sep++;
620 }
621
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622 memset(&td, 0, sizeof(struct thread_data));
623 td.o.ioengine = (char *)engine;
624 io_ops = load_ioengine(&td);
625
755dcbbd 626 if (!io_ops) {
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627 log_info("IO engine %s not found\n", engine);
628 return 1;
629 }
630
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TK
631 if (io_ops->options)
632 ret = show_cmd_help(io_ops->options, sep);
de890a1e 633 else
755dcbbd 634 log_info("IO engine %s has no options\n", io_ops->name);
de890a1e 635
d04f1d5b 636 free_ioengine(&td);
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637 return ret;
638}