1 /*
2 * QEMU throttling infrastructure
3 *
4 * Copyright (C) Nodalink, EURL. 2013-2014
5 * Copyright (C) Igalia, S.L. 2015
6 *
7 * Authors:
8 * Benoît Canet <benoit.canet@nodalink.com>
9 * Alberto Garcia <berto@igalia.com>
10 *
11 * This program is free software; you can redistribute it and/or
12 * modify it under the terms of the GNU General Public License as
13 * published by the Free Software Foundation; either version 2 or
14 * (at your option) version 3 of the License.
15 *
16 * This program is distributed in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 * GNU General Public License for more details.
20 *
21 * You should have received a copy of the GNU General Public License
22 * along with this program; if not, see <http://www.gnu.org/licenses/>.
23 */
24
25 #include "qemu/osdep.h"
26 #include "qapi/error.h"
27 #include "qemu/throttle.h"
28 #include "qemu/timer.h"
29 #include "block/aio.h"
30
31 /* This function make a bucket leak
32 *
33 * @bkt: the bucket to make leak
34 * @delta_ns: the time delta
35 */
throttle_leak_bucket(LeakyBucket * bkt,int64_t delta_ns)36 void throttle_leak_bucket(LeakyBucket *bkt, int64_t delta_ns)
37 {
38 double leak;
39
40 /* compute how much to leak */
41 leak = (bkt->avg * (double) delta_ns) / NANOSECONDS_PER_SECOND;
42
43 /* make the bucket leak */
44 bkt->level = MAX(bkt->level - leak, 0);
45
46 /* if we allow bursts for more than one second we also need to
47 * keep track of bkt->burst_level so the bkt->max goal per second
48 * is attained */
49 if (bkt->burst_length > 1) {
50 leak = (bkt->max * (double) delta_ns) / NANOSECONDS_PER_SECOND;
51 bkt->burst_level = MAX(bkt->burst_level - leak, 0);
52 }
53 }
54
55 /* Calculate the time delta since last leak and make proportionals leaks
56 *
57 * @now: the current timestamp in ns
58 */
throttle_do_leak(ThrottleState * ts,int64_t now)59 static void throttle_do_leak(ThrottleState *ts, int64_t now)
60 {
61 /* compute the time elapsed since the last leak */
62 int64_t delta_ns = now - ts->previous_leak;
63 int i;
64
65 ts->previous_leak = now;
66
67 if (delta_ns <= 0) {
68 return;
69 }
70
71 /* make each bucket leak */
72 for (i = 0; i < BUCKETS_COUNT; i++) {
73 throttle_leak_bucket(&ts->cfg.buckets[i], delta_ns);
74 }
75 }
76
77 /* do the real job of computing the time to wait
78 *
79 * @limit: the throttling limit
80 * @extra: the number of operation to delay
81 * @ret: the time to wait in ns
82 */
throttle_do_compute_wait(double limit,double extra)83 static int64_t throttle_do_compute_wait(double limit, double extra)
84 {
85 double wait = extra * NANOSECONDS_PER_SECOND;
86 wait /= limit;
87 return wait;
88 }
89
90 /* This function compute the wait time in ns that a leaky bucket should trigger
91 *
92 * @bkt: the leaky bucket we operate on
93 * @ret: the resulting wait time in ns or 0 if the operation can go through
94 */
throttle_compute_wait(LeakyBucket * bkt)95 int64_t throttle_compute_wait(LeakyBucket *bkt)
96 {
97 double extra; /* the number of extra units blocking the io */
98 double bucket_size; /* I/O before throttling to bkt->avg */
99 double burst_bucket_size; /* Before throttling to bkt->max */
100
101 if (!bkt->avg) {
102 return 0;
103 }
104
105 if (!bkt->max) {
106 /* If bkt->max is 0 we still want to allow short bursts of I/O
107 * from the guest, otherwise every other request will be throttled
108 * and performance will suffer considerably. */
109 bucket_size = (double) bkt->avg / 10;
110 burst_bucket_size = 0;
111 } else {
112 /* If we have a burst limit then we have to wait until all I/O
113 * at burst rate has finished before throttling to bkt->avg */
114 bucket_size = bkt->max * bkt->burst_length;
115 burst_bucket_size = (double) bkt->max / 10;
116 }
117
118 /* If the main bucket is full then we have to wait */
119 extra = bkt->level - bucket_size;
120 if (extra > 0) {
121 return throttle_do_compute_wait(bkt->avg, extra);
122 }
123
124 /* If the main bucket is not full yet we still have to check the
125 * burst bucket in order to enforce the burst limit */
126 if (bkt->burst_length > 1) {
127 assert(bkt->max > 0); /* see throttle_is_valid() */
128 extra = bkt->burst_level - burst_bucket_size;
129 if (extra > 0) {
130 return throttle_do_compute_wait(bkt->max, extra);
131 }
132 }
133
134 return 0;
135 }
136
137 /* This function compute the time that must be waited while this IO
138 *
139 * @direction: throttle direction
140 * @ret: time to wait
141 */
throttle_compute_wait_for(ThrottleState * ts,ThrottleDirection direction)142 static int64_t throttle_compute_wait_for(ThrottleState *ts,
143 ThrottleDirection direction)
144 {
145 static const BucketType to_check[THROTTLE_MAX][4] = {
146 {THROTTLE_BPS_TOTAL,
147 THROTTLE_OPS_TOTAL,
148 THROTTLE_BPS_READ,
149 THROTTLE_OPS_READ},
150 {THROTTLE_BPS_TOTAL,
151 THROTTLE_OPS_TOTAL,
152 THROTTLE_BPS_WRITE,
153 THROTTLE_OPS_WRITE}, };
154 int64_t wait, max_wait = 0;
155 int i;
156
157 for (i = 0; i < ARRAY_SIZE(to_check[THROTTLE_READ]); i++) {
158 BucketType index = to_check[direction][i];
159 wait = throttle_compute_wait(&ts->cfg.buckets[index]);
160 if (wait > max_wait) {
161 max_wait = wait;
162 }
163 }
164
165 return max_wait;
166 }
167
168 /* compute the timer for this type of operation
169 *
170 * @direction: throttle direction
171 * @now: the current clock timestamp
172 * @next_timestamp: the resulting timer
173 * @ret: true if a timer must be set
174 */
throttle_compute_timer(ThrottleState * ts,ThrottleDirection direction,int64_t now,int64_t * next_timestamp)175 static bool throttle_compute_timer(ThrottleState *ts,
176 ThrottleDirection direction,
177 int64_t now,
178 int64_t *next_timestamp)
179 {
180 int64_t wait;
181
182 /* leak proportionally to the time elapsed */
183 throttle_do_leak(ts, now);
184
185 /* compute the wait time if any */
186 wait = throttle_compute_wait_for(ts, direction);
187
188 /* if the code must wait compute when the next timer should fire */
189 if (wait) {
190 *next_timestamp = now + wait;
191 return true;
192 }
193
194 /* else no need to wait at all */
195 *next_timestamp = now;
196 return false;
197 }
198
199 /* Add timers to event loop */
throttle_timers_attach_aio_context(ThrottleTimers * tt,AioContext * new_context)200 void throttle_timers_attach_aio_context(ThrottleTimers *tt,
201 AioContext *new_context)
202 {
203 ThrottleDirection dir;
204
205 for (dir = THROTTLE_READ; dir < THROTTLE_MAX; dir++) {
206 if (tt->timer_cb[dir]) {
207 tt->timers[dir] =
208 aio_timer_new(new_context, tt->clock_type, SCALE_NS,
209 tt->timer_cb[dir], tt->timer_opaque);
210 }
211 }
212 }
213
214 /*
215 * Initialize the ThrottleConfig structure to a valid state
216 * @cfg: the config to initialize
217 */
throttle_config_init(ThrottleConfig * cfg)218 void throttle_config_init(ThrottleConfig *cfg)
219 {
220 unsigned i;
221 memset(cfg, 0, sizeof(*cfg));
222 for (i = 0; i < BUCKETS_COUNT; i++) {
223 cfg->buckets[i].burst_length = 1;
224 }
225 }
226
227 /* To be called first on the ThrottleState */
throttle_init(ThrottleState * ts)228 void throttle_init(ThrottleState *ts)
229 {
230 memset(ts, 0, sizeof(ThrottleState));
231 throttle_config_init(&ts->cfg);
232 }
233
234 /* To be called first on the ThrottleTimers */
throttle_timers_init(ThrottleTimers * tt,AioContext * aio_context,QEMUClockType clock_type,QEMUTimerCB * read_timer_cb,QEMUTimerCB * write_timer_cb,void * timer_opaque)235 void throttle_timers_init(ThrottleTimers *tt,
236 AioContext *aio_context,
237 QEMUClockType clock_type,
238 QEMUTimerCB *read_timer_cb,
239 QEMUTimerCB *write_timer_cb,
240 void *timer_opaque)
241 {
242 assert(read_timer_cb || write_timer_cb);
243 memset(tt, 0, sizeof(ThrottleTimers));
244
245 tt->clock_type = clock_type;
246 tt->timer_cb[THROTTLE_READ] = read_timer_cb;
247 tt->timer_cb[THROTTLE_WRITE] = write_timer_cb;
248 tt->timer_opaque = timer_opaque;
249 throttle_timers_attach_aio_context(tt, aio_context);
250 }
251
252 /* destroy a timer */
throttle_timer_destroy(QEMUTimer ** timer)253 static void throttle_timer_destroy(QEMUTimer **timer)
254 {
255 if (*timer == NULL) {
256 return;
257 }
258
259 timer_free(*timer);
260 *timer = NULL;
261 }
262
263 /* Remove timers from event loop */
throttle_timers_detach_aio_context(ThrottleTimers * tt)264 void throttle_timers_detach_aio_context(ThrottleTimers *tt)
265 {
266 ThrottleDirection dir;
267
268 for (dir = THROTTLE_READ; dir < THROTTLE_MAX; dir++) {
269 throttle_timer_destroy(&tt->timers[dir]);
270 }
271 }
272
273 /* To be called last on the ThrottleTimers */
throttle_timers_destroy(ThrottleTimers * tt)274 void throttle_timers_destroy(ThrottleTimers *tt)
275 {
276 throttle_timers_detach_aio_context(tt);
277 }
278
279 /* is any throttling timer configured */
throttle_timers_are_initialized(ThrottleTimers * tt)280 bool throttle_timers_are_initialized(ThrottleTimers *tt)
281 {
282 ThrottleDirection dir;
283
284 for (dir = THROTTLE_READ; dir < THROTTLE_MAX; dir++) {
285 if (tt->timers[dir]) {
286 return true;
287 }
288 }
289
290 return false;
291 }
292
293 /* Does any throttling must be done
294 *
295 * @cfg: the throttling configuration to inspect
296 * @ret: true if throttling must be done else false
297 */
throttle_enabled(ThrottleConfig * cfg)298 bool throttle_enabled(ThrottleConfig *cfg)
299 {
300 int i;
301
302 for (i = 0; i < BUCKETS_COUNT; i++) {
303 if (cfg->buckets[i].avg > 0) {
304 return true;
305 }
306 }
307
308 return false;
309 }
310
311 /* check if a throttling configuration is valid
312 * @cfg: the throttling configuration to inspect
313 * @ret: true if valid else false
314 * @errp: error object
315 */
throttle_is_valid(ThrottleConfig * cfg,Error ** errp)316 bool throttle_is_valid(ThrottleConfig *cfg, Error **errp)
317 {
318 int i;
319 bool bps_flag, ops_flag;
320 bool bps_max_flag, ops_max_flag;
321
322 bps_flag = cfg->buckets[THROTTLE_BPS_TOTAL].avg &&
323 (cfg->buckets[THROTTLE_BPS_READ].avg ||
324 cfg->buckets[THROTTLE_BPS_WRITE].avg);
325
326 ops_flag = cfg->buckets[THROTTLE_OPS_TOTAL].avg &&
327 (cfg->buckets[THROTTLE_OPS_READ].avg ||
328 cfg->buckets[THROTTLE_OPS_WRITE].avg);
329
330 bps_max_flag = cfg->buckets[THROTTLE_BPS_TOTAL].max &&
331 (cfg->buckets[THROTTLE_BPS_READ].max ||
332 cfg->buckets[THROTTLE_BPS_WRITE].max);
333
334 ops_max_flag = cfg->buckets[THROTTLE_OPS_TOTAL].max &&
335 (cfg->buckets[THROTTLE_OPS_READ].max ||
336 cfg->buckets[THROTTLE_OPS_WRITE].max);
337
338 if (bps_flag || ops_flag || bps_max_flag || ops_max_flag) {
339 error_setg(errp, "bps/iops/max total values and read/write values"
340 " cannot be used at the same time");
341 return false;
342 }
343
344 if (cfg->op_size &&
345 !cfg->buckets[THROTTLE_OPS_TOTAL].avg &&
346 !cfg->buckets[THROTTLE_OPS_READ].avg &&
347 !cfg->buckets[THROTTLE_OPS_WRITE].avg) {
348 error_setg(errp, "iops size requires an iops value to be set");
349 return false;
350 }
351
352 for (i = 0; i < BUCKETS_COUNT; i++) {
353 LeakyBucket *bkt = &cfg->buckets[i];
354 if (bkt->avg > THROTTLE_VALUE_MAX || bkt->max > THROTTLE_VALUE_MAX) {
355 error_setg(errp, "bps/iops/max values must be within [0, %lld]",
356 THROTTLE_VALUE_MAX);
357 return false;
358 }
359
360 if (!bkt->burst_length) {
361 error_setg(errp, "the burst length cannot be 0");
362 return false;
363 }
364
365 if (bkt->burst_length > 1 && !bkt->max) {
366 error_setg(errp, "burst length set without burst rate");
367 return false;
368 }
369
370 if (bkt->max && bkt->burst_length > THROTTLE_VALUE_MAX / bkt->max) {
371 error_setg(errp, "burst length too high for this burst rate");
372 return false;
373 }
374
375 if (bkt->max && !bkt->avg) {
376 error_setg(errp, "bps_max/iops_max require corresponding"
377 " bps/iops values");
378 return false;
379 }
380
381 if (bkt->max && bkt->max < bkt->avg) {
382 error_setg(errp, "bps_max/iops_max cannot be lower than bps/iops");
383 return false;
384 }
385 }
386
387 return true;
388 }
389
390 /* Used to configure the throttle
391 *
392 * @ts: the throttle state we are working on
393 * @clock_type: the group's clock_type
394 * @cfg: the config to set
395 */
throttle_config(ThrottleState * ts,QEMUClockType clock_type,ThrottleConfig * cfg)396 void throttle_config(ThrottleState *ts,
397 QEMUClockType clock_type,
398 ThrottleConfig *cfg)
399 {
400 int i;
401
402 ts->cfg = *cfg;
403
404 /* Zero bucket level */
405 for (i = 0; i < BUCKETS_COUNT; i++) {
406 ts->cfg.buckets[i].level = 0;
407 ts->cfg.buckets[i].burst_level = 0;
408 }
409
410 ts->previous_leak = qemu_clock_get_ns(clock_type);
411 }
412
413 /* used to get config
414 *
415 * @ts: the throttle state we are working on
416 * @cfg: the config to write
417 */
throttle_get_config(ThrottleState * ts,ThrottleConfig * cfg)418 void throttle_get_config(ThrottleState *ts, ThrottleConfig *cfg)
419 {
420 *cfg = ts->cfg;
421 }
422
423
424 /* Schedule the read or write timer if needed
425 *
426 * NOTE: this function is not unit tested due to it's usage of timer_mod
427 *
428 * @tt: the timers structure
429 * @direction: throttle direction
430 * @ret: true if the timer has been scheduled else false
431 */
throttle_schedule_timer(ThrottleState * ts,ThrottleTimers * tt,ThrottleDirection direction)432 bool throttle_schedule_timer(ThrottleState *ts,
433 ThrottleTimers *tt,
434 ThrottleDirection direction)
435 {
436 int64_t now = qemu_clock_get_ns(tt->clock_type);
437 int64_t next_timestamp;
438 QEMUTimer *timer;
439 bool must_wait;
440
441 assert(direction < THROTTLE_MAX);
442 timer = tt->timers[direction];
443 assert(timer);
444
445 must_wait = throttle_compute_timer(ts,
446 direction,
447 now,
448 &next_timestamp);
449
450 /* request not throttled */
451 if (!must_wait) {
452 return false;
453 }
454
455 /* request throttled and timer pending -> do nothing */
456 if (timer_pending(timer)) {
457 return true;
458 }
459
460 /* request throttled and timer not pending -> arm timer */
461 timer_mod(timer, next_timestamp);
462 return true;
463 }
464
465 /* do the accounting for this operation
466 *
467 * @direction: throttle direction
468 * @size: the size of the operation
469 */
throttle_account(ThrottleState * ts,ThrottleDirection direction,uint64_t size)470 void throttle_account(ThrottleState *ts, ThrottleDirection direction,
471 uint64_t size)
472 {
473 static const BucketType bucket_types_size[THROTTLE_MAX][2] = {
474 { THROTTLE_BPS_TOTAL, THROTTLE_BPS_READ },
475 { THROTTLE_BPS_TOTAL, THROTTLE_BPS_WRITE }
476 };
477 static const BucketType bucket_types_units[THROTTLE_MAX][2] = {
478 { THROTTLE_OPS_TOTAL, THROTTLE_OPS_READ },
479 { THROTTLE_OPS_TOTAL, THROTTLE_OPS_WRITE }
480 };
481 double units = 1.0;
482 unsigned i;
483
484 assert(direction < THROTTLE_MAX);
485 /* if cfg.op_size is defined and smaller than size we compute unit count */
486 if (ts->cfg.op_size && size > ts->cfg.op_size) {
487 units = (double) size / ts->cfg.op_size;
488 }
489
490 for (i = 0; i < ARRAY_SIZE(bucket_types_size[THROTTLE_READ]); i++) {
491 LeakyBucket *bkt;
492
493 bkt = &ts->cfg.buckets[bucket_types_size[direction][i]];
494 bkt->level += size;
495 if (bkt->burst_length > 1) {
496 bkt->burst_level += size;
497 }
498
499 bkt = &ts->cfg.buckets[bucket_types_units[direction][i]];
500 bkt->level += units;
501 if (bkt->burst_length > 1) {
502 bkt->burst_level += units;
503 }
504 }
505 }
506
507 /* return a ThrottleConfig based on the options in a ThrottleLimits
508 *
509 * @arg: the ThrottleLimits object to read from
510 * @cfg: the ThrottleConfig to edit
511 * @errp: error object
512 */
throttle_limits_to_config(ThrottleLimits * arg,ThrottleConfig * cfg,Error ** errp)513 void throttle_limits_to_config(ThrottleLimits *arg, ThrottleConfig *cfg,
514 Error **errp)
515 {
516 if (arg->has_bps_total) {
517 cfg->buckets[THROTTLE_BPS_TOTAL].avg = arg->bps_total;
518 }
519 if (arg->has_bps_read) {
520 cfg->buckets[THROTTLE_BPS_READ].avg = arg->bps_read;
521 }
522 if (arg->has_bps_write) {
523 cfg->buckets[THROTTLE_BPS_WRITE].avg = arg->bps_write;
524 }
525
526 if (arg->has_iops_total) {
527 cfg->buckets[THROTTLE_OPS_TOTAL].avg = arg->iops_total;
528 }
529 if (arg->has_iops_read) {
530 cfg->buckets[THROTTLE_OPS_READ].avg = arg->iops_read;
531 }
532 if (arg->has_iops_write) {
533 cfg->buckets[THROTTLE_OPS_WRITE].avg = arg->iops_write;
534 }
535
536 if (arg->has_bps_total_max) {
537 cfg->buckets[THROTTLE_BPS_TOTAL].max = arg->bps_total_max;
538 }
539 if (arg->has_bps_read_max) {
540 cfg->buckets[THROTTLE_BPS_READ].max = arg->bps_read_max;
541 }
542 if (arg->has_bps_write_max) {
543 cfg->buckets[THROTTLE_BPS_WRITE].max = arg->bps_write_max;
544 }
545 if (arg->has_iops_total_max) {
546 cfg->buckets[THROTTLE_OPS_TOTAL].max = arg->iops_total_max;
547 }
548 if (arg->has_iops_read_max) {
549 cfg->buckets[THROTTLE_OPS_READ].max = arg->iops_read_max;
550 }
551 if (arg->has_iops_write_max) {
552 cfg->buckets[THROTTLE_OPS_WRITE].max = arg->iops_write_max;
553 }
554
555 if (arg->has_bps_total_max_length) {
556 if (arg->bps_total_max_length > UINT_MAX) {
557 error_setg(errp, "bps-total-max-length value must be in"
558 " the range [0, %u]", UINT_MAX);
559 return;
560 }
561 cfg->buckets[THROTTLE_BPS_TOTAL].burst_length = arg->bps_total_max_length;
562 }
563 if (arg->has_bps_read_max_length) {
564 if (arg->bps_read_max_length > UINT_MAX) {
565 error_setg(errp, "bps-read-max-length value must be in"
566 " the range [0, %u]", UINT_MAX);
567 return;
568 }
569 cfg->buckets[THROTTLE_BPS_READ].burst_length = arg->bps_read_max_length;
570 }
571 if (arg->has_bps_write_max_length) {
572 if (arg->bps_write_max_length > UINT_MAX) {
573 error_setg(errp, "bps-write-max-length value must be in"
574 " the range [0, %u]", UINT_MAX);
575 return;
576 }
577 cfg->buckets[THROTTLE_BPS_WRITE].burst_length = arg->bps_write_max_length;
578 }
579 if (arg->has_iops_total_max_length) {
580 if (arg->iops_total_max_length > UINT_MAX) {
581 error_setg(errp, "iops-total-max-length value must be in"
582 " the range [0, %u]", UINT_MAX);
583 return;
584 }
585 cfg->buckets[THROTTLE_OPS_TOTAL].burst_length = arg->iops_total_max_length;
586 }
587 if (arg->has_iops_read_max_length) {
588 if (arg->iops_read_max_length > UINT_MAX) {
589 error_setg(errp, "iops-read-max-length value must be in"
590 " the range [0, %u]", UINT_MAX);
591 return;
592 }
593 cfg->buckets[THROTTLE_OPS_READ].burst_length = arg->iops_read_max_length;
594 }
595 if (arg->has_iops_write_max_length) {
596 if (arg->iops_write_max_length > UINT_MAX) {
597 error_setg(errp, "iops-write-max-length value must be in"
598 " the range [0, %u]", UINT_MAX);
599 return;
600 }
601 cfg->buckets[THROTTLE_OPS_WRITE].burst_length = arg->iops_write_max_length;
602 }
603
604 if (arg->has_iops_size) {
605 cfg->op_size = arg->iops_size;
606 }
607
608 throttle_is_valid(cfg, errp);
609 }
610
611 /* write the options of a ThrottleConfig to a ThrottleLimits
612 *
613 * @cfg: the ThrottleConfig to read from
614 * @var: the ThrottleLimits to write to
615 */
throttle_config_to_limits(ThrottleConfig * cfg,ThrottleLimits * var)616 void throttle_config_to_limits(ThrottleConfig *cfg, ThrottleLimits *var)
617 {
618 var->bps_total = cfg->buckets[THROTTLE_BPS_TOTAL].avg;
619 var->bps_read = cfg->buckets[THROTTLE_BPS_READ].avg;
620 var->bps_write = cfg->buckets[THROTTLE_BPS_WRITE].avg;
621 var->iops_total = cfg->buckets[THROTTLE_OPS_TOTAL].avg;
622 var->iops_read = cfg->buckets[THROTTLE_OPS_READ].avg;
623 var->iops_write = cfg->buckets[THROTTLE_OPS_WRITE].avg;
624 var->bps_total_max = cfg->buckets[THROTTLE_BPS_TOTAL].max;
625 var->bps_read_max = cfg->buckets[THROTTLE_BPS_READ].max;
626 var->bps_write_max = cfg->buckets[THROTTLE_BPS_WRITE].max;
627 var->iops_total_max = cfg->buckets[THROTTLE_OPS_TOTAL].max;
628 var->iops_read_max = cfg->buckets[THROTTLE_OPS_READ].max;
629 var->iops_write_max = cfg->buckets[THROTTLE_OPS_WRITE].max;
630 var->bps_total_max_length = cfg->buckets[THROTTLE_BPS_TOTAL].burst_length;
631 var->bps_read_max_length = cfg->buckets[THROTTLE_BPS_READ].burst_length;
632 var->bps_write_max_length = cfg->buckets[THROTTLE_BPS_WRITE].burst_length;
633 var->iops_total_max_length = cfg->buckets[THROTTLE_OPS_TOTAL].burst_length;
634 var->iops_read_max_length = cfg->buckets[THROTTLE_OPS_READ].burst_length;
635 var->iops_write_max_length = cfg->buckets[THROTTLE_OPS_WRITE].burst_length;
636 var->iops_size = cfg->op_size;
637
638 var->has_bps_total = true;
639 var->has_bps_read = true;
640 var->has_bps_write = true;
641 var->has_iops_total = true;
642 var->has_iops_read = true;
643 var->has_iops_write = true;
644 var->has_bps_total_max = true;
645 var->has_bps_read_max = true;
646 var->has_bps_write_max = true;
647 var->has_iops_total_max = true;
648 var->has_iops_read_max = true;
649 var->has_iops_write_max = true;
650 var->has_bps_read_max_length = true;
651 var->has_bps_total_max_length = true;
652 var->has_bps_write_max_length = true;
653 var->has_iops_total_max_length = true;
654 var->has_iops_read_max_length = true;
655 var->has_iops_write_max_length = true;
656 var->has_iops_size = true;
657 }
658