Commit | Line | Data |
---|---|---|
6d5a9bc2 JA |
1 | /* |
2 | * Read a file and write the contents to stdout. If a given read takes | |
3 | * longer than 'max_us' time, then we schedule a new thread to handle | |
4 | * the next read. This avoids the coordinated omission problem, where | |
5 | * one request appears to take a long time, but in reality a lot of | |
6 | * requests would have been slow, but we don't notice since new submissions | |
7 | * are not being issued if just 1 is held up. | |
8 | * | |
9 | * One test case: | |
10 | * | |
11 | * $ time (./read-to-pipe-async -f randfile.gz | gzip -dc > outfile; sync) | |
12 | * | |
13 | * This will read randfile.gz and log the latencies of doing so, while | |
14 | * piping the output to gzip to decompress it. Any latencies over max_us | |
15 | * are logged when they happen, and latency buckets are displayed at the | |
16 | * end of the run | |
17 | * | |
18 | * gcc -Wall -g -O2 -o read-to-pipe-async read-to-pipe-async.c -lpthread | |
19 | * | |
20 | * Copyright (C) 2016 Jens Axboe | |
21 | * | |
22 | */ | |
78b66d32 | 23 | |
6d5a9bc2 JA |
24 | #include <stdio.h> |
25 | #include <stdlib.h> | |
26 | #include <unistd.h> | |
27 | #include <fcntl.h> | |
28 | #include <sys/time.h> | |
29 | #include <sys/types.h> | |
30 | #include <sys/stat.h> | |
31 | #include <inttypes.h> | |
32 | #include <string.h> | |
33 | #include <pthread.h> | |
34 | #include <errno.h> | |
35 | #include <assert.h> | |
36 | ||
37 | #include "../flist.h" | |
38 | ||
1f081ec0 DP |
39 | #include "compiler/compiler.h" |
40 | ||
6d5a9bc2 JA |
41 | static int bs = 4096; |
42 | static int max_us = 10000; | |
43 | static char *file; | |
44 | static int separate_writer = 1; | |
45 | ||
46 | #define PLAT_BITS 8 | |
47 | #define PLAT_VAL (1 << PLAT_BITS) | |
48 | #define PLAT_GROUP_NR 19 | |
49 | #define PLAT_NR (PLAT_GROUP_NR * PLAT_VAL) | |
50 | #define PLAT_LIST_MAX 20 | |
51 | ||
1f081ec0 DP |
52 | #ifndef NDEBUG |
53 | #define CHECK_ZERO_OR_ABORT(code) assert(code) | |
54 | #else | |
55 | #define CHECK_ZERO_OR_ABORT(code) \ | |
56 | do { \ | |
57 | if (fio_unlikely((code) != 0)) { \ | |
58 | log_err("failed checking code %i != 0", (code)); \ | |
59 | abort(); \ | |
60 | } \ | |
61 | } while (0) | |
62 | #endif | |
63 | ||
6d5a9bc2 JA |
64 | struct stats { |
65 | unsigned int plat[PLAT_NR]; | |
66 | unsigned int nr_samples; | |
67 | unsigned int max; | |
68 | unsigned int min; | |
69 | unsigned int over; | |
70 | }; | |
71 | ||
72 | static double plist[PLAT_LIST_MAX] = { 50.0, 75.0, 90.0, 95.0, 99.0, 99.5, 99.9, 99.99, 99.999, 99.9999, }; | |
73 | ||
74 | struct thread_data { | |
75 | int exit; | |
76 | int done; | |
77 | pthread_mutex_t lock; | |
78 | pthread_cond_t cond; | |
79 | pthread_mutex_t done_lock; | |
80 | pthread_cond_t done_cond; | |
81 | pthread_t thread; | |
82 | }; | |
83 | ||
84 | struct writer_thread { | |
85 | struct flist_head list; | |
86 | struct flist_head done_list; | |
87 | struct stats s; | |
88 | struct thread_data thread; | |
89 | }; | |
90 | ||
91 | struct reader_thread { | |
92 | struct flist_head list; | |
93 | struct flist_head done_list; | |
94 | int started; | |
95 | int busy; | |
96 | int write_seq; | |
97 | struct stats s; | |
98 | struct thread_data thread; | |
99 | }; | |
100 | ||
101 | struct work_item { | |
102 | struct flist_head list; | |
103 | void *buf; | |
104 | size_t buf_size; | |
105 | off_t off; | |
106 | int fd; | |
107 | int seq; | |
108 | struct writer_thread *writer; | |
109 | struct reader_thread *reader; | |
110 | pthread_mutex_t lock; | |
111 | pthread_cond_t cond; | |
112 | pthread_t thread; | |
113 | }; | |
114 | ||
115 | static struct reader_thread reader_thread; | |
116 | static struct writer_thread writer_thread; | |
117 | ||
6a087e5a | 118 | uint64_t utime_since(const struct timespec *s, const struct timespec *e) |
6d5a9bc2 JA |
119 | { |
120 | long sec, usec; | |
121 | uint64_t ret; | |
122 | ||
123 | sec = e->tv_sec - s->tv_sec; | |
6a087e5a | 124 | usec = (e->tv_nsec - s->tv_nsec) / 1000; |
6d5a9bc2 JA |
125 | if (sec > 0 && usec < 0) { |
126 | sec--; | |
127 | usec += 1000000; | |
128 | } | |
129 | ||
130 | if (sec < 0 || (sec == 0 && usec < 0)) | |
131 | return 0; | |
132 | ||
133 | ret = sec * 1000000ULL + usec; | |
134 | ||
135 | return ret; | |
136 | } | |
137 | ||
1f081ec0 | 138 | static struct work_item *find_seq(struct writer_thread *w, int seq) |
6d5a9bc2 JA |
139 | { |
140 | struct work_item *work; | |
141 | struct flist_head *entry; | |
142 | ||
143 | if (flist_empty(&w->list)) | |
144 | return NULL; | |
145 | ||
146 | flist_for_each(entry, &w->list) { | |
147 | work = flist_entry(entry, struct work_item, list); | |
148 | if (work->seq == seq) | |
149 | return work; | |
150 | } | |
151 | ||
152 | return NULL; | |
153 | } | |
154 | ||
155 | static unsigned int plat_val_to_idx(unsigned int val) | |
156 | { | |
157 | unsigned int msb, error_bits, base, offset; | |
158 | ||
159 | /* Find MSB starting from bit 0 */ | |
160 | if (val == 0) | |
161 | msb = 0; | |
162 | else | |
163 | msb = sizeof(val)*8 - __builtin_clz(val) - 1; | |
164 | ||
165 | /* | |
166 | * MSB <= (PLAT_BITS-1), cannot be rounded off. Use | |
167 | * all bits of the sample as index | |
168 | */ | |
169 | if (msb <= PLAT_BITS) | |
170 | return val; | |
171 | ||
172 | /* Compute the number of error bits to discard*/ | |
173 | error_bits = msb - PLAT_BITS; | |
174 | ||
175 | /* Compute the number of buckets before the group */ | |
176 | base = (error_bits + 1) << PLAT_BITS; | |
177 | ||
178 | /* | |
179 | * Discard the error bits and apply the mask to find the | |
180 | * index for the buckets in the group | |
181 | */ | |
182 | offset = (PLAT_VAL - 1) & (val >> error_bits); | |
183 | ||
184 | /* Make sure the index does not exceed (array size - 1) */ | |
185 | return (base + offset) < (PLAT_NR - 1) ? | |
186 | (base + offset) : (PLAT_NR - 1); | |
187 | } | |
188 | ||
189 | /* | |
190 | * Convert the given index of the bucket array to the value | |
191 | * represented by the bucket | |
192 | */ | |
193 | static unsigned int plat_idx_to_val(unsigned int idx) | |
194 | { | |
195 | unsigned int error_bits, k, base; | |
196 | ||
197 | assert(idx < PLAT_NR); | |
198 | ||
199 | /* MSB <= (PLAT_BITS-1), cannot be rounded off. Use | |
200 | * all bits of the sample as index */ | |
201 | if (idx < (PLAT_VAL << 1)) | |
202 | return idx; | |
203 | ||
204 | /* Find the group and compute the minimum value of that group */ | |
205 | error_bits = (idx >> PLAT_BITS) - 1; | |
206 | base = 1 << (error_bits + PLAT_BITS); | |
207 | ||
208 | /* Find its bucket number of the group */ | |
209 | k = idx % PLAT_VAL; | |
210 | ||
211 | /* Return the mean of the range of the bucket */ | |
212 | return base + ((k + 0.5) * (1 << error_bits)); | |
213 | } | |
214 | ||
215 | static void add_lat(struct stats *s, unsigned int us, const char *name) | |
216 | { | |
217 | int lat_index = 0; | |
218 | ||
219 | if (us > s->max) | |
220 | s->max = us; | |
221 | if (us < s->min) | |
222 | s->min = us; | |
223 | ||
224 | if (us > max_us) { | |
225 | fprintf(stderr, "%s latency=%u usec\n", name, us); | |
226 | s->over++; | |
227 | } | |
228 | ||
229 | lat_index = plat_val_to_idx(us); | |
230 | __sync_fetch_and_add(&s->plat[lat_index], 1); | |
231 | __sync_fetch_and_add(&s->nr_samples, 1); | |
232 | } | |
233 | ||
234 | static int write_work(struct work_item *work) | |
235 | { | |
6a087e5a | 236 | struct timespec s, e; |
6d5a9bc2 JA |
237 | ssize_t ret; |
238 | ||
6a087e5a | 239 | clock_gettime(CLOCK_MONOTONIC, &s); |
6d5a9bc2 | 240 | ret = write(STDOUT_FILENO, work->buf, work->buf_size); |
1f081ec0 DP |
241 | if (ret < 0) |
242 | return (int)ret; | |
6a087e5a | 243 | clock_gettime(CLOCK_MONOTONIC, &e); |
6d5a9bc2 JA |
244 | assert(ret == work->buf_size); |
245 | ||
246 | add_lat(&work->writer->s, utime_since(&s, &e), "write"); | |
247 | return work->seq + 1; | |
248 | } | |
249 | ||
28cacec4 JA |
250 | static void thread_exiting(struct thread_data *thread) |
251 | { | |
252 | __sync_fetch_and_add(&thread->done, 1); | |
253 | pthread_cond_signal(&thread->done_cond); | |
254 | } | |
255 | ||
6d5a9bc2 JA |
256 | static void *writer_fn(void *data) |
257 | { | |
258 | struct writer_thread *wt = data; | |
259 | struct work_item *work; | |
1f081ec0 | 260 | int seq = 1; |
6d5a9bc2 JA |
261 | |
262 | work = NULL; | |
1f081ec0 | 263 | while (!(seq < 0) && (!wt->thread.exit || !flist_empty(&wt->list))) { |
6d5a9bc2 JA |
264 | pthread_mutex_lock(&wt->thread.lock); |
265 | ||
45bf2f40 | 266 | if (work) |
6d5a9bc2 | 267 | flist_add_tail(&work->list, &wt->done_list); |
6d5a9bc2 JA |
268 | |
269 | work = find_seq(wt, seq); | |
270 | if (work) | |
271 | flist_del_init(&work->list); | |
272 | else | |
273 | pthread_cond_wait(&wt->thread.cond, &wt->thread.lock); | |
274 | ||
275 | pthread_mutex_unlock(&wt->thread.lock); | |
276 | ||
277 | if (work) | |
278 | seq = write_work(work); | |
279 | } | |
280 | ||
28cacec4 | 281 | thread_exiting(&wt->thread); |
6d5a9bc2 JA |
282 | return NULL; |
283 | } | |
284 | ||
285 | static void reader_work(struct work_item *work) | |
286 | { | |
6a087e5a | 287 | struct timespec s, e; |
6d5a9bc2 JA |
288 | ssize_t ret; |
289 | size_t left; | |
290 | void *buf; | |
291 | off_t off; | |
292 | ||
6a087e5a | 293 | clock_gettime(CLOCK_MONOTONIC, &s); |
6d5a9bc2 JA |
294 | |
295 | left = work->buf_size; | |
296 | buf = work->buf; | |
297 | off = work->off; | |
298 | while (left) { | |
299 | ret = pread(work->fd, buf, left, off); | |
300 | if (!ret) { | |
301 | fprintf(stderr, "zero read\n"); | |
302 | break; | |
303 | } else if (ret < 0) { | |
304 | fprintf(stderr, "errno=%d\n", errno); | |
305 | break; | |
306 | } | |
307 | left -= ret; | |
308 | off += ret; | |
309 | buf += ret; | |
310 | } | |
311 | ||
6a087e5a | 312 | clock_gettime(CLOCK_MONOTONIC, &e); |
6d5a9bc2 JA |
313 | |
314 | add_lat(&work->reader->s, utime_since(&s, &e), "read"); | |
315 | ||
316 | pthread_cond_signal(&work->cond); | |
317 | ||
318 | if (separate_writer) { | |
319 | pthread_mutex_lock(&work->writer->thread.lock); | |
320 | flist_add_tail(&work->list, &work->writer->list); | |
321 | pthread_mutex_unlock(&work->writer->thread.lock); | |
322 | pthread_cond_signal(&work->writer->thread.cond); | |
323 | } else { | |
324 | struct reader_thread *rt = work->reader; | |
325 | struct work_item *next = NULL; | |
326 | struct flist_head *entry; | |
327 | ||
328 | /* | |
329 | * Write current work if it matches in sequence. | |
330 | */ | |
331 | if (work->seq == rt->write_seq) | |
332 | goto write_it; | |
333 | ||
334 | pthread_mutex_lock(&rt->thread.lock); | |
335 | ||
336 | flist_add_tail(&work->list, &rt->done_list); | |
337 | ||
338 | /* | |
339 | * See if the next work item is here, if so, write it | |
340 | */ | |
341 | work = NULL; | |
342 | flist_for_each(entry, &rt->done_list) { | |
343 | next = flist_entry(entry, struct work_item, list); | |
344 | if (next->seq == rt->write_seq) { | |
345 | work = next; | |
346 | flist_del(&work->list); | |
347 | break; | |
348 | } | |
349 | } | |
350 | ||
351 | pthread_mutex_unlock(&rt->thread.lock); | |
352 | ||
353 | if (work) { | |
354 | write_it: | |
355 | write_work(work); | |
356 | __sync_fetch_and_add(&rt->write_seq, 1); | |
357 | } | |
358 | } | |
359 | } | |
360 | ||
361 | static void *reader_one_off(void *data) | |
362 | { | |
363 | reader_work(data); | |
364 | return NULL; | |
365 | } | |
366 | ||
367 | static void *reader_fn(void *data) | |
368 | { | |
369 | struct reader_thread *rt = data; | |
370 | struct work_item *work; | |
371 | ||
372 | while (!rt->thread.exit || !flist_empty(&rt->list)) { | |
373 | work = NULL; | |
374 | pthread_mutex_lock(&rt->thread.lock); | |
375 | if (!flist_empty(&rt->list)) { | |
376 | work = flist_first_entry(&rt->list, struct work_item, list); | |
377 | flist_del_init(&work->list); | |
378 | } else | |
379 | pthread_cond_wait(&rt->thread.cond, &rt->thread.lock); | |
380 | pthread_mutex_unlock(&rt->thread.lock); | |
381 | ||
382 | if (work) { | |
28cacec4 | 383 | __sync_fetch_and_add(&rt->busy, 1); |
6d5a9bc2 | 384 | reader_work(work); |
28cacec4 | 385 | __sync_fetch_and_sub(&rt->busy, 1); |
6d5a9bc2 JA |
386 | } |
387 | } | |
388 | ||
28cacec4 | 389 | thread_exiting(&rt->thread); |
6d5a9bc2 JA |
390 | return NULL; |
391 | } | |
392 | ||
393 | static void queue_work(struct reader_thread *rt, struct work_item *work) | |
394 | { | |
395 | if (!rt->started) { | |
396 | pthread_mutex_lock(&rt->thread.lock); | |
397 | flist_add_tail(&work->list, &rt->list); | |
398 | pthread_mutex_unlock(&rt->thread.lock); | |
399 | ||
400 | rt->started = 1; | |
401 | pthread_create(&rt->thread.thread, NULL, reader_fn, rt); | |
402 | } else if (!rt->busy && !pthread_mutex_trylock(&rt->thread.lock)) { | |
403 | flist_add_tail(&work->list, &rt->list); | |
404 | pthread_mutex_unlock(&rt->thread.lock); | |
405 | ||
406 | pthread_cond_signal(&rt->thread.cond); | |
407 | } else { | |
408 | int ret = pthread_create(&work->thread, NULL, reader_one_off, work); | |
2c1520d7 | 409 | if (ret) { |
6d5a9bc2 | 410 | fprintf(stderr, "pthread_create=%d\n", ret); |
2c1520d7 BVA |
411 | } else { |
412 | ret = pthread_detach(work->thread); | |
413 | if (ret) | |
414 | fprintf(stderr, "pthread_detach=%d\n", ret); | |
415 | } | |
6d5a9bc2 JA |
416 | } |
417 | } | |
418 | ||
419 | static unsigned int calc_percentiles(unsigned int *io_u_plat, unsigned long nr, | |
420 | unsigned int **output) | |
421 | { | |
422 | unsigned long sum = 0; | |
423 | unsigned int len, i, j = 0; | |
424 | unsigned int oval_len = 0; | |
425 | unsigned int *ovals = NULL; | |
426 | int is_last; | |
427 | ||
428 | len = 0; | |
429 | while (len < PLAT_LIST_MAX && plist[len] != 0.0) | |
430 | len++; | |
431 | ||
432 | if (!len) | |
433 | return 0; | |
434 | ||
435 | /* | |
436 | * Calculate bucket values, note down max and min values | |
437 | */ | |
438 | is_last = 0; | |
439 | for (i = 0; i < PLAT_NR && !is_last; i++) { | |
440 | sum += io_u_plat[i]; | |
441 | while (sum >= (plist[j] / 100.0 * nr)) { | |
442 | assert(plist[j] <= 100.0); | |
443 | ||
444 | if (j == oval_len) { | |
445 | oval_len += 100; | |
446 | ovals = realloc(ovals, oval_len * sizeof(unsigned int)); | |
447 | } | |
448 | ||
449 | ovals[j] = plat_idx_to_val(i); | |
450 | is_last = (j == len - 1); | |
451 | if (is_last) | |
452 | break; | |
453 | ||
454 | j++; | |
455 | } | |
456 | } | |
457 | ||
458 | *output = ovals; | |
459 | return len; | |
460 | } | |
461 | ||
462 | static void show_latencies(struct stats *s, const char *msg) | |
463 | { | |
464 | unsigned int *ovals = NULL; | |
465 | unsigned int len, i; | |
466 | ||
467 | len = calc_percentiles(s->plat, s->nr_samples, &ovals); | |
468 | if (len) { | |
469 | fprintf(stderr, "Latency percentiles (usec) (%s)\n", msg); | |
470 | for (i = 0; i < len; i++) | |
471 | fprintf(stderr, "\t%2.4fth: %u\n", plist[i], ovals[i]); | |
472 | } | |
473 | ||
474 | if (ovals) | |
475 | free(ovals); | |
476 | ||
477 | fprintf(stderr, "\tOver=%u, min=%u, max=%u\n", s->over, s->min, s->max); | |
478 | } | |
479 | ||
480 | static void init_thread(struct thread_data *thread) | |
481 | { | |
78b66d32 BVA |
482 | pthread_condattr_t cattr; |
483 | int ret; | |
484 | ||
485 | ret = pthread_condattr_init(&cattr); | |
1f081ec0 | 486 | CHECK_ZERO_OR_ABORT(ret); |
78b66d32 BVA |
487 | #ifdef CONFIG_PTHREAD_CONDATTR_SETCLOCK |
488 | ret = pthread_condattr_setclock(&cattr, CLOCK_MONOTONIC); | |
1f081ec0 | 489 | CHECK_ZERO_OR_ABORT(ret); |
78b66d32 BVA |
490 | #endif |
491 | pthread_cond_init(&thread->cond, &cattr); | |
492 | pthread_cond_init(&thread->done_cond, &cattr); | |
6d5a9bc2 JA |
493 | pthread_mutex_init(&thread->lock, NULL); |
494 | pthread_mutex_init(&thread->done_lock, NULL); | |
495 | thread->exit = 0; | |
496 | } | |
497 | ||
498 | static void exit_thread(struct thread_data *thread, | |
499 | void fn(struct writer_thread *), | |
500 | struct writer_thread *wt) | |
501 | { | |
28cacec4 | 502 | __sync_fetch_and_add(&thread->exit, 1); |
6d5a9bc2 JA |
503 | pthread_cond_signal(&thread->cond); |
504 | ||
505 | while (!thread->done) { | |
506 | pthread_mutex_lock(&thread->done_lock); | |
507 | ||
508 | if (fn) { | |
53280a1d | 509 | struct timespec ts; |
6d5a9bc2 | 510 | |
78b66d32 BVA |
511 | #ifdef CONFIG_PTHREAD_CONDATTR_SETCLOCK |
512 | clock_gettime(CLOCK_MONOTONIC, &ts); | |
513 | #else | |
514 | clock_gettime(CLOCK_REALTIME, &ts); | |
515 | #endif | |
516 | ts.tv_sec++; | |
6d5a9bc2 | 517 | |
53280a1d | 518 | pthread_cond_timedwait(&thread->done_cond, &thread->done_lock, &ts); |
6d5a9bc2 JA |
519 | fn(wt); |
520 | } else | |
521 | pthread_cond_wait(&thread->done_cond, &thread->done_lock); | |
522 | ||
523 | pthread_mutex_unlock(&thread->done_lock); | |
524 | } | |
525 | } | |
526 | ||
527 | static int usage(char *argv[]) | |
528 | { | |
529 | fprintf(stderr, "%s: [-b blocksize] [-t max usec] [-w separate writer] -f file\n", argv[0]); | |
530 | return 1; | |
531 | } | |
532 | ||
533 | static int parse_options(int argc, char *argv[]) | |
534 | { | |
535 | int c; | |
536 | ||
537 | while ((c = getopt(argc, argv, "f:b:t:w:")) != -1) { | |
538 | switch (c) { | |
539 | case 'f': | |
a06aec04 BVA |
540 | if (file) |
541 | return usage(argv); | |
6d5a9bc2 JA |
542 | file = strdup(optarg); |
543 | break; | |
544 | case 'b': | |
545 | bs = atoi(optarg); | |
546 | break; | |
547 | case 't': | |
548 | max_us = atoi(optarg); | |
549 | break; | |
550 | case 'w': | |
551 | separate_writer = atoi(optarg); | |
552 | if (!separate_writer) | |
553 | fprintf(stderr, "inline writing is broken\n"); | |
554 | break; | |
555 | case '?': | |
556 | default: | |
557 | return usage(argv); | |
558 | } | |
559 | } | |
560 | ||
561 | if (!file) | |
562 | return usage(argv); | |
563 | ||
564 | return 0; | |
565 | } | |
566 | ||
567 | static void prune_done_entries(struct writer_thread *wt) | |
568 | { | |
569 | FLIST_HEAD(list); | |
570 | ||
571 | if (flist_empty(&wt->done_list)) | |
572 | return; | |
573 | ||
574 | if (pthread_mutex_trylock(&wt->thread.lock)) | |
575 | return; | |
576 | ||
577 | if (!flist_empty(&wt->done_list)) | |
578 | flist_splice_init(&wt->done_list, &list); | |
579 | pthread_mutex_unlock(&wt->thread.lock); | |
580 | ||
581 | while (!flist_empty(&list)) { | |
582 | struct work_item *work; | |
583 | ||
584 | work = flist_first_entry(&list, struct work_item, list); | |
585 | flist_del(&work->list); | |
586 | ||
587 | pthread_cond_destroy(&work->cond); | |
588 | pthread_mutex_destroy(&work->lock); | |
589 | free(work->buf); | |
590 | free(work); | |
591 | } | |
592 | } | |
593 | ||
594 | int main(int argc, char *argv[]) | |
595 | { | |
78b66d32 | 596 | pthread_condattr_t cattr; |
6a087e5a | 597 | struct timespec s, re, we; |
6d5a9bc2 JA |
598 | struct reader_thread *rt; |
599 | struct writer_thread *wt; | |
600 | unsigned long rate; | |
b38cc6cb | 601 | uint64_t elapsed; |
6d5a9bc2 JA |
602 | struct stat sb; |
603 | size_t bytes; | |
604 | off_t off; | |
605 | int fd, seq; | |
78b66d32 | 606 | int ret; |
6d5a9bc2 JA |
607 | |
608 | if (parse_options(argc, argv)) | |
609 | return 1; | |
610 | ||
611 | fd = open(file, O_RDONLY); | |
612 | if (fd < 0) { | |
613 | perror("open"); | |
614 | return 2; | |
615 | } | |
616 | ||
617 | if (fstat(fd, &sb) < 0) { | |
618 | perror("stat"); | |
619 | return 3; | |
620 | } | |
621 | ||
622 | wt = &writer_thread; | |
623 | init_thread(&wt->thread); | |
624 | INIT_FLIST_HEAD(&wt->list); | |
625 | INIT_FLIST_HEAD(&wt->done_list); | |
626 | wt->s.max = 0; | |
627 | wt->s.min = -1U; | |
628 | pthread_create(&wt->thread.thread, NULL, writer_fn, wt); | |
629 | ||
630 | rt = &reader_thread; | |
631 | init_thread(&rt->thread); | |
632 | INIT_FLIST_HEAD(&rt->list); | |
633 | INIT_FLIST_HEAD(&rt->done_list); | |
634 | rt->s.max = 0; | |
635 | rt->s.min = -1U; | |
636 | rt->write_seq = 1; | |
637 | ||
638 | off = 0; | |
639 | seq = 0; | |
640 | bytes = 0; | |
641 | ||
78b66d32 | 642 | ret = pthread_condattr_init(&cattr); |
1f081ec0 | 643 | CHECK_ZERO_OR_ABORT(ret); |
78b66d32 BVA |
644 | #ifdef CONFIG_PTHREAD_CONDATTR_SETCLOCK |
645 | ret = pthread_condattr_setclock(&cattr, CLOCK_MONOTONIC); | |
1f081ec0 | 646 | CHECK_ZERO_OR_ABORT(ret); |
78b66d32 BVA |
647 | #endif |
648 | ||
6a087e5a | 649 | clock_gettime(CLOCK_MONOTONIC, &s); |
6d5a9bc2 JA |
650 | |
651 | while (sb.st_size) { | |
652 | struct work_item *work; | |
653 | size_t this_len; | |
53280a1d | 654 | struct timespec ts; |
6d5a9bc2 JA |
655 | |
656 | prune_done_entries(wt); | |
657 | ||
658 | this_len = sb.st_size; | |
659 | if (this_len > bs) | |
660 | this_len = bs; | |
661 | ||
662 | work = calloc(1, sizeof(*work)); | |
663 | work->buf = malloc(this_len); | |
664 | work->buf_size = this_len; | |
665 | work->off = off; | |
666 | work->fd = fd; | |
667 | work->seq = ++seq; | |
668 | work->writer = wt; | |
669 | work->reader = rt; | |
78b66d32 | 670 | pthread_cond_init(&work->cond, &cattr); |
6d5a9bc2 JA |
671 | pthread_mutex_init(&work->lock, NULL); |
672 | ||
673 | queue_work(rt, work); | |
674 | ||
78b66d32 BVA |
675 | #ifdef CONFIG_PTHREAD_CONDATTR_SETCLOCK |
676 | clock_gettime(CLOCK_MONOTONIC, &ts); | |
677 | #else | |
678 | clock_gettime(CLOCK_REALTIME, &ts); | |
679 | #endif | |
53280a1d JA |
680 | ts.tv_nsec += max_us * 1000ULL; |
681 | if (ts.tv_nsec >= 1000000000ULL) { | |
682 | ts.tv_nsec -= 1000000000ULL; | |
683 | ts.tv_sec++; | |
6d5a9bc2 JA |
684 | } |
685 | ||
686 | pthread_mutex_lock(&work->lock); | |
53280a1d | 687 | pthread_cond_timedwait(&work->cond, &work->lock, &ts); |
6d5a9bc2 JA |
688 | pthread_mutex_unlock(&work->lock); |
689 | ||
690 | off += this_len; | |
691 | sb.st_size -= this_len; | |
692 | bytes += this_len; | |
693 | } | |
694 | ||
695 | exit_thread(&rt->thread, NULL, NULL); | |
6a087e5a | 696 | clock_gettime(CLOCK_MONOTONIC, &re); |
6d5a9bc2 JA |
697 | |
698 | exit_thread(&wt->thread, prune_done_entries, wt); | |
6a087e5a | 699 | clock_gettime(CLOCK_MONOTONIC, &we); |
6d5a9bc2 JA |
700 | |
701 | show_latencies(&rt->s, "READERS"); | |
702 | show_latencies(&wt->s, "WRITERS"); | |
703 | ||
704 | bytes /= 1024; | |
b38cc6cb BVA |
705 | elapsed = utime_since(&s, &re); |
706 | rate = elapsed ? (bytes * 1000UL * 1000UL) / elapsed : 0; | |
4870138d | 707 | fprintf(stderr, "Read rate (KiB/sec) : %lu\n", rate); |
b38cc6cb BVA |
708 | elapsed = utime_since(&s, &we); |
709 | rate = elapsed ? (bytes * 1000UL * 1000UL) / elapsed : 0; | |
4870138d | 710 | fprintf(stderr, "Write rate (KiB/sec): %lu\n", rate); |
6d5a9bc2 JA |
711 | |
712 | close(fd); | |
713 | return 0; | |
714 | } |