Fix potential divide-by-zero in calc_iops()
[fio.git] / workqueue.c
CommitLineData
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1/*
2 * Rated submission helpers
3 *
4 * Copyright (C) 2015 Jens Axboe <axboe@kernel.dk>
5 *
6 */
7#include <unistd.h>
8
9#include "fio.h"
10#include "ioengine.h"
11#include "flist.h"
12#include "workqueue.h"
13#include "lib/getrusage.h"
14
15struct submit_worker {
16 pthread_t thread;
17 pthread_mutex_t lock;
18 pthread_cond_t cond;
19 struct flist_head work_list;
20 unsigned int flags;
21 unsigned int index;
22 uint64_t seq;
23 struct workqueue *wq;
24 struct thread_data td;
25};
26
27enum {
28 SW_F_IDLE = 1 << 0,
29 SW_F_RUNNING = 1 << 1,
30 SW_F_EXIT = 1 << 2,
31 SW_F_EXITED = 1 << 3,
32 SW_F_ACCOUNTED = 1 << 4,
33 SW_F_ERROR = 1 << 5,
34};
35
36static struct submit_worker *__get_submit_worker(struct workqueue *wq,
37 unsigned int start,
38 unsigned int end,
39 struct submit_worker **best)
40{
41 struct submit_worker *sw = NULL;
42
43 while (start <= end) {
44 sw = &wq->workers[start];
45 if (sw->flags & SW_F_IDLE)
46 return sw;
47 if (!(*best) || sw->seq < (*best)->seq)
48 *best = sw;
49 start++;
50 }
51
52 return NULL;
53}
54
55static struct submit_worker *get_submit_worker(struct workqueue *wq)
56{
57 unsigned int next = wq->next_free_worker;
58 struct submit_worker *sw, *best = NULL;
59
60 assert(next < wq->max_workers);
61
62 sw = __get_submit_worker(wq, next, wq->max_workers - 1, &best);
63 if (!sw && next)
64 sw = __get_submit_worker(wq, 0, next - 1, &best);
65
66 /*
67 * No truly idle found, use best match
68 */
69 if (!sw)
70 sw = best;
71
72 if (sw->index == wq->next_free_worker) {
73 if (sw->index + 1 < wq->max_workers)
74 wq->next_free_worker = sw->index + 1;
75 else
76 wq->next_free_worker = 0;
77 }
78
79 return sw;
80}
81
82static int all_sw_idle(struct workqueue *wq)
83{
84 int i;
85
86 for (i = 0; i < wq->max_workers; i++) {
87 struct submit_worker *sw = &wq->workers[i];
88
89 if (!(sw->flags & SW_F_IDLE))
90 return 0;
91 }
92
93 return 1;
94}
95
96/*
97 * Must be serialized wrt workqueue_enqueue() by caller
98 */
99void workqueue_flush(struct workqueue *wq)
100{
101 wq->wake_idle = 1;
102
103 while (!all_sw_idle(wq)) {
104 pthread_mutex_lock(&wq->flush_lock);
105 pthread_cond_wait(&wq->flush_cond, &wq->flush_lock);
106 pthread_mutex_unlock(&wq->flush_lock);
107 }
108
109 wq->wake_idle = 0;
110}
111
112/*
113 * Must be serialized by caller.
114 */
115int workqueue_enqueue(struct workqueue *wq, struct io_u *io_u)
116{
117 struct submit_worker *sw;
118
119 sw = get_submit_worker(wq);
120 if (sw) {
121 const enum fio_ddir ddir = acct_ddir(io_u);
122 struct thread_data *parent = wq->td;
123
124 if (ddir_rw(ddir)) {
125 parent->io_issues[ddir]++;
126 parent->io_issue_bytes[ddir] += io_u->xfer_buflen;
127 }
128
129 pthread_mutex_lock(&sw->lock);
130 flist_add_tail(&io_u->verify_list, &sw->work_list);
131 sw->seq = ++wq->work_seq;
132 sw->flags &= ~SW_F_IDLE;
133 pthread_mutex_unlock(&sw->lock);
134
135 pthread_cond_signal(&sw->cond);
136 return FIO_Q_QUEUED;
137 }
138
139 return FIO_Q_BUSY;
140}
141
142static void handle_list(struct submit_worker *sw, struct flist_head *list)
143{
144 struct workqueue *wq = sw->wq;
145 struct io_u *io_u;
146
147 while (!flist_empty(list)) {
148 io_u = flist_first_entry(list, struct io_u, verify_list);
149 flist_del_init(&io_u->verify_list);
150 wq->fn(&sw->td, io_u);
151 }
152}
153
154static int init_submit_worker(struct submit_worker *sw)
155{
156 struct thread_data *parent = sw->wq->td;
157 struct thread_data *td = &sw->td;
158 int fio_unused ret;
159
160 memcpy(&td->o, &parent->o, sizeof(td->o));
161 memcpy(&td->ts, &parent->ts, sizeof(td->ts));
162 td->o.uid = td->o.gid = -1U;
163 dup_files(td, parent);
164 fio_options_mem_dupe(td);
165
166 if (ioengine_load(td))
167 goto err;
168
169 if (td->o.odirect)
170 td->io_ops->flags |= FIO_RAWIO;
171
172 td->pid = gettid();
173
174 INIT_FLIST_HEAD(&td->io_log_list);
175 INIT_FLIST_HEAD(&td->io_hist_list);
176 INIT_FLIST_HEAD(&td->verify_list);
177 INIT_FLIST_HEAD(&td->trim_list);
178 INIT_FLIST_HEAD(&td->next_rand_list);
179 td->io_hist_tree = RB_ROOT;
180
181 td->o.iodepth = 1;
182 if (td_io_init(td))
183 goto err_io_init;
184
185 fio_gettime(&td->epoch, NULL);
186 fio_getrusage(&td->ru_start);
187 clear_io_state(td);
188
189 td_set_runstate(td, TD_RUNNING);
190 td->flags |= TD_F_CHILD;
191 td->parent = parent;
192 return 0;
193
194err_io_init:
195 close_ioengine(td);
196err:
197 return 1;
198}
199
f5cd2907 200#ifdef CONFIG_SFAA
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201static void sum_val(uint64_t *dst, uint64_t *src)
202{
203 if (*src) {
204 __sync_fetch_and_add(dst, *src);
205 *src = 0;
206 }
207}
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208#else
209static void sum_val(uint64_t *dst, uint64_t *src)
210{
211 if (*src) {
212 *dst += *src;
213 *src = 0;
214 }
215}
216#endif
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217
218static void sum_ddir(struct thread_data *dst, struct thread_data *src,
219 enum fio_ddir ddir)
220{
f5cd2907 221#ifndef CONFIG_SFAA
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222 pthread_mutex_lock(&dst->io_wq.stat_lock);
223 pthread_mutex_lock(&src->io_wq.stat_lock);
224#endif
225
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226 sum_val(&dst->io_bytes[ddir], &src->io_bytes[ddir]);
227 sum_val(&dst->io_blocks[ddir], &src->io_blocks[ddir]);
228 sum_val(&dst->this_io_blocks[ddir], &src->this_io_blocks[ddir]);
229 sum_val(&dst->this_io_bytes[ddir], &src->this_io_bytes[ddir]);
230 sum_val(&dst->bytes_done[ddir], &src->bytes_done[ddir]);
2a274336 231
f5cd2907 232#ifndef CONFIG_SFAA
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233 pthread_mutex_unlock(&src->io_wq.stat_lock);
234 pthread_mutex_unlock(&dst->io_wq.stat_lock);
235#endif
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236}
237
238static void update_accounting(struct submit_worker *sw)
239{
240 struct thread_data *src = &sw->td;
241 struct thread_data *dst = sw->wq->td;
242
243 if (td_read(src))
244 sum_ddir(dst, src, DDIR_READ);
245 if (td_write(src))
246 sum_ddir(dst, src, DDIR_WRITE);
247 if (td_trim(src))
248 sum_ddir(dst, src, DDIR_TRIM);
249}
250
251static void *worker_thread(void *data)
252{
253 struct submit_worker *sw = data;
254 struct workqueue *wq = sw->wq;
255 struct thread_data *td = &sw->td;
256 unsigned int eflags = 0, ret;
257 FLIST_HEAD(local_list);
258
259 ret = init_submit_worker(sw);
260 pthread_mutex_lock(&sw->lock);
261 sw->flags |= SW_F_RUNNING;
262 if (ret)
263 sw->flags |= SW_F_ERROR;
264 pthread_mutex_unlock(&sw->lock);
265
266 pthread_mutex_lock(&wq->flush_lock);
267 pthread_cond_signal(&wq->flush_cond);
268 pthread_mutex_unlock(&wq->flush_lock);
269
270 if (sw->flags & SW_F_ERROR)
271 goto done;
272
273 while (1) {
274 pthread_mutex_lock(&sw->lock);
275
276 if (flist_empty(&sw->work_list)) {
277 if (sw->flags & SW_F_EXIT) {
278 pthread_mutex_unlock(&sw->lock);
279 break;
280 }
281
282 if (td->io_u_queued || td->cur_depth ||
283 td->io_u_in_flight) {
284 pthread_mutex_unlock(&sw->lock);
285 io_u_quiesce(td);
286 pthread_mutex_lock(&sw->lock);
287 }
288
289 /*
290 * We dropped and reaquired the lock, check
291 * state again.
292 */
293 if (!flist_empty(&sw->work_list))
294 goto handle_work;
295
296 if (sw->flags & SW_F_EXIT) {
297 pthread_mutex_unlock(&sw->lock);
298 break;
299 } else if (!(sw->flags & SW_F_IDLE)) {
300 sw->flags |= SW_F_IDLE;
301 wq->next_free_worker = sw->index;
302 if (wq->wake_idle)
303 pthread_cond_signal(&wq->flush_cond);
304 }
305 update_accounting(sw);
306 pthread_cond_wait(&sw->cond, &sw->lock);
307 } else {
308handle_work:
309 flist_splice_init(&sw->work_list, &local_list);
310 }
311 pthread_mutex_unlock(&sw->lock);
312 handle_list(sw, &local_list);
313 }
314
315 update_accounting(sw);
316
317done:
318 pthread_mutex_lock(&sw->lock);
319 sw->flags |= (SW_F_EXITED | eflags);
320 pthread_mutex_unlock(&sw->lock);
321 return NULL;
322}
323
324static void free_worker(struct submit_worker *sw)
325{
326 struct thread_data *td = &sw->td;
327
328 fio_options_free(td);
329 close_and_free_files(td);
330 if (td->io_ops)
331 close_ioengine(td);
332 td_set_runstate(td, TD_EXITED);
333
334 pthread_cond_destroy(&sw->cond);
335 pthread_mutex_destroy(&sw->lock);
336}
337
338static void shutdown_worker(struct submit_worker *sw, unsigned int *sum_cnt)
339{
340 struct thread_data *parent = sw->wq->td;
341
342 pthread_join(sw->thread, NULL);
343 (*sum_cnt)++;
344 sum_thread_stats(&parent->ts, &sw->td.ts, *sum_cnt);
345 free_worker(sw);
346}
347
348void workqueue_exit(struct workqueue *wq)
349{
350 unsigned int shutdown, sum_cnt = 0;
351 struct submit_worker *sw;
352 int i;
353
354 for (i = 0; i < wq->max_workers; i++) {
355 sw = &wq->workers[i];
356
357 pthread_mutex_lock(&sw->lock);
358 sw->flags |= SW_F_EXIT;
359 pthread_cond_signal(&sw->cond);
360 pthread_mutex_unlock(&sw->lock);
361 }
362
363 do {
364 shutdown = 0;
365 for (i = 0; i < wq->max_workers; i++) {
366 sw = &wq->workers[i];
367 if (sw->flags & SW_F_ACCOUNTED)
368 continue;
369 sw->flags |= SW_F_ACCOUNTED;
370 shutdown_worker(sw, &sum_cnt);
371 shutdown++;
372 }
373 } while (shutdown && shutdown != wq->max_workers);
374
375 free(wq->workers);
376 pthread_mutex_destroy(&wq->flush_lock);
377 pthread_cond_destroy(&wq->flush_cond);
2a274336 378 pthread_mutex_destroy(&wq->stat_lock);
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379}
380
381static int start_worker(struct workqueue *wq, unsigned int index)
382{
383 struct submit_worker *sw = &wq->workers[index];
384 int ret;
385
386 INIT_FLIST_HEAD(&sw->work_list);
387 pthread_cond_init(&sw->cond, NULL);
388 pthread_mutex_init(&sw->lock, NULL);
389 sw->wq = wq;
390 sw->index = index;
391
392 ret = pthread_create(&sw->thread, NULL, worker_thread, sw);
393 if (!ret) {
394 pthread_mutex_lock(&sw->lock);
395 sw->flags = SW_F_IDLE;
396 pthread_mutex_unlock(&sw->lock);
397 return 0;
398 }
399
400 free_worker(sw);
401 return 1;
402}
403
404int workqueue_init(struct thread_data *td, struct workqueue *wq,
405 workqueue_fn *fn, unsigned max_pending)
406{
407 unsigned int running;
408 int i, error;
409
410 wq->max_workers = max_pending;
411 wq->td = td;
412 wq->fn = fn;
413 wq->work_seq = 0;
414 wq->next_free_worker = 0;
415 pthread_cond_init(&wq->flush_cond, NULL);
416 pthread_mutex_init(&wq->flush_lock, NULL);
2a274336 417 pthread_mutex_init(&wq->stat_lock, NULL);
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418
419 wq->workers = calloc(wq->max_workers, sizeof(struct submit_worker));
420
421 for (i = 0; i < wq->max_workers; i++)
422 if (start_worker(wq, i))
423 break;
424
425 wq->max_workers = i;
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426 if (!wq->max_workers)
427 goto err;
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428
429 /*
430 * Wait for them all to be started and initialized
431 */
432 error = 0;
433 do {
434 struct submit_worker *sw;
435
436 running = 0;
437 pthread_mutex_lock(&wq->flush_lock);
438 for (i = 0; i < wq->max_workers; i++) {
439 sw = &wq->workers[i];
440 pthread_mutex_lock(&sw->lock);
441 if (sw->flags & SW_F_RUNNING)
442 running++;
443 if (sw->flags & SW_F_ERROR)
444 error++;
445 pthread_mutex_unlock(&sw->lock);
446 }
447
448 if (error || running == wq->max_workers) {
449 pthread_mutex_unlock(&wq->flush_lock);
450 break;
451 }
452
453 pthread_cond_wait(&wq->flush_cond, &wq->flush_lock);
454 pthread_mutex_unlock(&wq->flush_lock);
455 } while (1);
456
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457 if (!error)
458 return 0;
a9da8ab2 459
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460err:
461 log_err("Can't create rate workqueue\n");
462 td_verror(td, ESRCH, "workqueue_init");
463 workqueue_exit(wq);
464 return 1;
a9da8ab2 465}