net: hub: suppress warnings of no host network for qtest
[qemu/kevin.git] / block / throttle-groups.c
blob5d8213a443c585eb195cb7270d9b9372a6aaddbd
1 /*
2 * QEMU block throttling group infrastructure
4 * Copyright (C) Nodalink, EURL. 2014
5 * Copyright (C) Igalia, S.L. 2015
7 * Authors:
8 * BenoƮt Canet <benoit.canet@nodalink.com>
9 * Alberto Garcia <berto@igalia.com>
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.
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.
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/>.
25 #include "qemu/osdep.h"
26 #include "sysemu/block-backend.h"
27 #include "block/throttle-groups.h"
28 #include "qemu/throttle-options.h"
29 #include "qemu/queue.h"
30 #include "qemu/thread.h"
31 #include "sysemu/qtest.h"
32 #include "qapi/error.h"
33 #include "qapi/qapi-visit-block-core.h"
34 #include "qom/object.h"
35 #include "qom/object_interfaces.h"
37 static void throttle_group_obj_init(Object *obj);
38 static void throttle_group_obj_complete(UserCreatable *obj, Error **errp);
39 static void timer_cb(ThrottleGroupMember *tgm, bool is_write);
41 /* The ThrottleGroup structure (with its ThrottleState) is shared
42 * among different ThrottleGroupMembers and it's independent from
43 * AioContext, so in order to use it from different threads it needs
44 * its own locking.
46 * This locking is however handled internally in this file, so it's
47 * transparent to outside users.
49 * The whole ThrottleGroup structure is private and invisible to
50 * outside users, that only use it through its ThrottleState.
52 * In addition to the ThrottleGroup structure, ThrottleGroupMember has
53 * fields that need to be accessed by other members of the group and
54 * therefore also need to be protected by this lock. Once a
55 * ThrottleGroupMember is registered in a group those fields can be accessed
56 * by other threads any time.
58 * Again, all this is handled internally and is mostly transparent to
59 * the outside. The 'throttle_timers' field however has an additional
60 * constraint because it may be temporarily invalid (see for example
61 * blk_set_aio_context()). Therefore in this file a thread will
62 * access some other ThrottleGroupMember's timers only after verifying that
63 * that ThrottleGroupMember has throttled requests in the queue.
65 typedef struct ThrottleGroup {
66 Object parent_obj;
68 /* refuse individual property change if initialization is complete */
69 bool is_initialized;
70 char *name; /* This is constant during the lifetime of the group */
72 QemuMutex lock; /* This lock protects the following four fields */
73 ThrottleState ts;
74 QLIST_HEAD(, ThrottleGroupMember) head;
75 ThrottleGroupMember *tokens[2];
76 bool any_timer_armed[2];
77 QEMUClockType clock_type;
79 /* This field is protected by the global QEMU mutex */
80 QTAILQ_ENTRY(ThrottleGroup) list;
81 } ThrottleGroup;
83 /* This is protected by the global QEMU mutex */
84 static QTAILQ_HEAD(, ThrottleGroup) throttle_groups =
85 QTAILQ_HEAD_INITIALIZER(throttle_groups);
88 /* This function reads throttle_groups and must be called under the global
89 * mutex.
91 static ThrottleGroup *throttle_group_by_name(const char *name)
93 ThrottleGroup *iter;
95 /* Look for an existing group with that name */
96 QTAILQ_FOREACH(iter, &throttle_groups, list) {
97 if (!g_strcmp0(name, iter->name)) {
98 return iter;
102 return NULL;
105 /* This function reads throttle_groups and must be called under the global
106 * mutex.
108 bool throttle_group_exists(const char *name)
110 return throttle_group_by_name(name) != NULL;
113 /* Increments the reference count of a ThrottleGroup given its name.
115 * If no ThrottleGroup is found with the given name a new one is
116 * created.
118 * This function edits throttle_groups and must be called under the global
119 * mutex.
121 * @name: the name of the ThrottleGroup
122 * @ret: the ThrottleState member of the ThrottleGroup
124 ThrottleState *throttle_group_incref(const char *name)
126 ThrottleGroup *tg = NULL;
128 /* Look for an existing group with that name */
129 tg = throttle_group_by_name(name);
131 if (tg) {
132 object_ref(OBJECT(tg));
133 } else {
134 /* Create a new one if not found */
135 /* new ThrottleGroup obj will have a refcnt = 1 */
136 tg = THROTTLE_GROUP(object_new(TYPE_THROTTLE_GROUP));
137 tg->name = g_strdup(name);
138 throttle_group_obj_complete(USER_CREATABLE(tg), &error_abort);
141 return &tg->ts;
144 /* Decrease the reference count of a ThrottleGroup.
146 * When the reference count reaches zero the ThrottleGroup is
147 * destroyed.
149 * This function edits throttle_groups and must be called under the global
150 * mutex.
152 * @ts: The ThrottleGroup to unref, given by its ThrottleState member
154 void throttle_group_unref(ThrottleState *ts)
156 ThrottleGroup *tg = container_of(ts, ThrottleGroup, ts);
157 object_unref(OBJECT(tg));
160 /* Get the name from a ThrottleGroupMember's group. The name (and the pointer)
161 * is guaranteed to remain constant during the lifetime of the group.
163 * @tgm: a ThrottleGroupMember
164 * @ret: the name of the group.
166 const char *throttle_group_get_name(ThrottleGroupMember *tgm)
168 ThrottleGroup *tg = container_of(tgm->throttle_state, ThrottleGroup, ts);
169 return tg->name;
172 /* Return the next ThrottleGroupMember in the round-robin sequence, simulating
173 * a circular list.
175 * This assumes that tg->lock is held.
177 * @tgm: the current ThrottleGroupMember
178 * @ret: the next ThrottleGroupMember in the sequence
180 static ThrottleGroupMember *throttle_group_next_tgm(ThrottleGroupMember *tgm)
182 ThrottleState *ts = tgm->throttle_state;
183 ThrottleGroup *tg = container_of(ts, ThrottleGroup, ts);
184 ThrottleGroupMember *next = QLIST_NEXT(tgm, round_robin);
186 if (!next) {
187 next = QLIST_FIRST(&tg->head);
190 return next;
194 * Return whether a ThrottleGroupMember has pending requests.
196 * This assumes that tg->lock is held.
198 * @tgm: the ThrottleGroupMember
199 * @is_write: the type of operation (read/write)
200 * @ret: whether the ThrottleGroupMember has pending requests.
202 static inline bool tgm_has_pending_reqs(ThrottleGroupMember *tgm,
203 bool is_write)
205 return tgm->pending_reqs[is_write];
208 /* Return the next ThrottleGroupMember in the round-robin sequence with pending
209 * I/O requests.
211 * This assumes that tg->lock is held.
213 * @tgm: the current ThrottleGroupMember
214 * @is_write: the type of operation (read/write)
215 * @ret: the next ThrottleGroupMember with pending requests, or tgm if
216 * there is none.
218 static ThrottleGroupMember *next_throttle_token(ThrottleGroupMember *tgm,
219 bool is_write)
221 ThrottleState *ts = tgm->throttle_state;
222 ThrottleGroup *tg = container_of(ts, ThrottleGroup, ts);
223 ThrottleGroupMember *token, *start;
225 /* If this member has its I/O limits disabled then it means that
226 * it's being drained. Skip the round-robin search and return tgm
227 * immediately if it has pending requests. Otherwise we could be
228 * forcing it to wait for other member's throttled requests. */
229 if (tgm_has_pending_reqs(tgm, is_write) &&
230 atomic_read(&tgm->io_limits_disabled)) {
231 return tgm;
234 start = token = tg->tokens[is_write];
236 /* get next bs round in round robin style */
237 token = throttle_group_next_tgm(token);
238 while (token != start && !tgm_has_pending_reqs(token, is_write)) {
239 token = throttle_group_next_tgm(token);
242 /* If no IO are queued for scheduling on the next round robin token
243 * then decide the token is the current tgm because chances are
244 * the current tgm got the current request queued.
246 if (token == start && !tgm_has_pending_reqs(token, is_write)) {
247 token = tgm;
250 /* Either we return the original TGM, or one with pending requests */
251 assert(token == tgm || tgm_has_pending_reqs(token, is_write));
253 return token;
256 /* Check if the next I/O request for a ThrottleGroupMember needs to be
257 * throttled or not. If there's no timer set in this group, set one and update
258 * the token accordingly.
260 * This assumes that tg->lock is held.
262 * @tgm: the current ThrottleGroupMember
263 * @is_write: the type of operation (read/write)
264 * @ret: whether the I/O request needs to be throttled or not
266 static bool throttle_group_schedule_timer(ThrottleGroupMember *tgm,
267 bool is_write)
269 ThrottleState *ts = tgm->throttle_state;
270 ThrottleGroup *tg = container_of(ts, ThrottleGroup, ts);
271 ThrottleTimers *tt = &tgm->throttle_timers;
272 bool must_wait;
274 if (atomic_read(&tgm->io_limits_disabled)) {
275 return false;
278 /* Check if any of the timers in this group is already armed */
279 if (tg->any_timer_armed[is_write]) {
280 return true;
283 must_wait = throttle_schedule_timer(ts, tt, is_write);
285 /* If a timer just got armed, set tgm as the current token */
286 if (must_wait) {
287 tg->tokens[is_write] = tgm;
288 tg->any_timer_armed[is_write] = true;
291 return must_wait;
294 /* Start the next pending I/O request for a ThrottleGroupMember. Return whether
295 * any request was actually pending.
297 * @tgm: the current ThrottleGroupMember
298 * @is_write: the type of operation (read/write)
300 static bool coroutine_fn throttle_group_co_restart_queue(ThrottleGroupMember *tgm,
301 bool is_write)
303 bool ret;
305 qemu_co_mutex_lock(&tgm->throttled_reqs_lock);
306 ret = qemu_co_queue_next(&tgm->throttled_reqs[is_write]);
307 qemu_co_mutex_unlock(&tgm->throttled_reqs_lock);
309 return ret;
312 /* Look for the next pending I/O request and schedule it.
314 * This assumes that tg->lock is held.
316 * @tgm: the current ThrottleGroupMember
317 * @is_write: the type of operation (read/write)
319 static void schedule_next_request(ThrottleGroupMember *tgm, bool is_write)
321 ThrottleState *ts = tgm->throttle_state;
322 ThrottleGroup *tg = container_of(ts, ThrottleGroup, ts);
323 bool must_wait;
324 ThrottleGroupMember *token;
326 /* Check if there's any pending request to schedule next */
327 token = next_throttle_token(tgm, is_write);
328 if (!tgm_has_pending_reqs(token, is_write)) {
329 return;
332 /* Set a timer for the request if it needs to be throttled */
333 must_wait = throttle_group_schedule_timer(token, is_write);
335 /* If it doesn't have to wait, queue it for immediate execution */
336 if (!must_wait) {
337 /* Give preference to requests from the current tgm */
338 if (qemu_in_coroutine() &&
339 throttle_group_co_restart_queue(tgm, is_write)) {
340 token = tgm;
341 } else {
342 ThrottleTimers *tt = &token->throttle_timers;
343 int64_t now = qemu_clock_get_ns(tg->clock_type);
344 timer_mod(tt->timers[is_write], now);
345 tg->any_timer_armed[is_write] = true;
347 tg->tokens[is_write] = token;
351 /* Check if an I/O request needs to be throttled, wait and set a timer
352 * if necessary, and schedule the next request using a round robin
353 * algorithm.
355 * @tgm: the current ThrottleGroupMember
356 * @bytes: the number of bytes for this I/O
357 * @is_write: the type of operation (read/write)
359 void coroutine_fn throttle_group_co_io_limits_intercept(ThrottleGroupMember *tgm,
360 unsigned int bytes,
361 bool is_write)
363 bool must_wait;
364 ThrottleGroupMember *token;
365 ThrottleGroup *tg = container_of(tgm->throttle_state, ThrottleGroup, ts);
366 qemu_mutex_lock(&tg->lock);
368 /* First we check if this I/O has to be throttled. */
369 token = next_throttle_token(tgm, is_write);
370 must_wait = throttle_group_schedule_timer(token, is_write);
372 /* Wait if there's a timer set or queued requests of this type */
373 if (must_wait || tgm->pending_reqs[is_write]) {
374 tgm->pending_reqs[is_write]++;
375 qemu_mutex_unlock(&tg->lock);
376 qemu_co_mutex_lock(&tgm->throttled_reqs_lock);
377 qemu_co_queue_wait(&tgm->throttled_reqs[is_write],
378 &tgm->throttled_reqs_lock);
379 qemu_co_mutex_unlock(&tgm->throttled_reqs_lock);
380 qemu_mutex_lock(&tg->lock);
381 tgm->pending_reqs[is_write]--;
384 /* The I/O will be executed, so do the accounting */
385 throttle_account(tgm->throttle_state, is_write, bytes);
387 /* Schedule the next request */
388 schedule_next_request(tgm, is_write);
390 qemu_mutex_unlock(&tg->lock);
393 typedef struct {
394 ThrottleGroupMember *tgm;
395 bool is_write;
396 } RestartData;
398 static void coroutine_fn throttle_group_restart_queue_entry(void *opaque)
400 RestartData *data = opaque;
401 ThrottleGroupMember *tgm = data->tgm;
402 ThrottleState *ts = tgm->throttle_state;
403 ThrottleGroup *tg = container_of(ts, ThrottleGroup, ts);
404 bool is_write = data->is_write;
405 bool empty_queue;
407 empty_queue = !throttle_group_co_restart_queue(tgm, is_write);
409 /* If the request queue was empty then we have to take care of
410 * scheduling the next one */
411 if (empty_queue) {
412 qemu_mutex_lock(&tg->lock);
413 schedule_next_request(tgm, is_write);
414 qemu_mutex_unlock(&tg->lock);
417 g_free(data);
420 static void throttle_group_restart_queue(ThrottleGroupMember *tgm, bool is_write)
422 Coroutine *co;
423 RestartData *rd = g_new0(RestartData, 1);
425 rd->tgm = tgm;
426 rd->is_write = is_write;
428 /* This function is called when a timer is fired or when
429 * throttle_group_restart_tgm() is called. Either way, there can
430 * be no timer pending on this tgm at this point */
431 assert(!timer_pending(tgm->throttle_timers.timers[is_write]));
433 co = qemu_coroutine_create(throttle_group_restart_queue_entry, rd);
434 aio_co_enter(tgm->aio_context, co);
437 void throttle_group_restart_tgm(ThrottleGroupMember *tgm)
439 int i;
441 if (tgm->throttle_state) {
442 for (i = 0; i < 2; i++) {
443 QEMUTimer *t = tgm->throttle_timers.timers[i];
444 if (timer_pending(t)) {
445 /* If there's a pending timer on this tgm, fire it now */
446 timer_del(t);
447 timer_cb(tgm, i);
448 } else {
449 /* Else run the next request from the queue manually */
450 throttle_group_restart_queue(tgm, i);
456 /* Update the throttle configuration for a particular group. Similar
457 * to throttle_config(), but guarantees atomicity within the
458 * throttling group.
460 * @tgm: a ThrottleGroupMember that is a member of the group
461 * @cfg: the configuration to set
463 void throttle_group_config(ThrottleGroupMember *tgm, ThrottleConfig *cfg)
465 ThrottleState *ts = tgm->throttle_state;
466 ThrottleGroup *tg = container_of(ts, ThrottleGroup, ts);
467 qemu_mutex_lock(&tg->lock);
468 throttle_config(ts, tg->clock_type, cfg);
469 qemu_mutex_unlock(&tg->lock);
471 throttle_group_restart_tgm(tgm);
474 /* Get the throttle configuration from a particular group. Similar to
475 * throttle_get_config(), but guarantees atomicity within the
476 * throttling group.
478 * @tgm: a ThrottleGroupMember that is a member of the group
479 * @cfg: the configuration will be written here
481 void throttle_group_get_config(ThrottleGroupMember *tgm, ThrottleConfig *cfg)
483 ThrottleState *ts = tgm->throttle_state;
484 ThrottleGroup *tg = container_of(ts, ThrottleGroup, ts);
485 qemu_mutex_lock(&tg->lock);
486 throttle_get_config(ts, cfg);
487 qemu_mutex_unlock(&tg->lock);
490 /* ThrottleTimers callback. This wakes up a request that was waiting
491 * because it had been throttled.
493 * @tgm: the ThrottleGroupMember whose request had been throttled
494 * @is_write: the type of operation (read/write)
496 static void timer_cb(ThrottleGroupMember *tgm, bool is_write)
498 ThrottleState *ts = tgm->throttle_state;
499 ThrottleGroup *tg = container_of(ts, ThrottleGroup, ts);
501 /* The timer has just been fired, so we can update the flag */
502 qemu_mutex_lock(&tg->lock);
503 tg->any_timer_armed[is_write] = false;
504 qemu_mutex_unlock(&tg->lock);
506 /* Run the request that was waiting for this timer */
507 throttle_group_restart_queue(tgm, is_write);
510 static void read_timer_cb(void *opaque)
512 timer_cb(opaque, false);
515 static void write_timer_cb(void *opaque)
517 timer_cb(opaque, true);
520 /* Register a ThrottleGroupMember from the throttling group, also initializing
521 * its timers and updating its throttle_state pointer to point to it. If a
522 * throttling group with that name does not exist yet, it will be created.
524 * This function edits throttle_groups and must be called under the global
525 * mutex.
527 * @tgm: the ThrottleGroupMember to insert
528 * @groupname: the name of the group
529 * @ctx: the AioContext to use
531 void throttle_group_register_tgm(ThrottleGroupMember *tgm,
532 const char *groupname,
533 AioContext *ctx)
535 int i;
536 ThrottleState *ts = throttle_group_incref(groupname);
537 ThrottleGroup *tg = container_of(ts, ThrottleGroup, ts);
539 tgm->throttle_state = ts;
540 tgm->aio_context = ctx;
542 qemu_mutex_lock(&tg->lock);
543 /* If the ThrottleGroup is new set this ThrottleGroupMember as the token */
544 for (i = 0; i < 2; i++) {
545 if (!tg->tokens[i]) {
546 tg->tokens[i] = tgm;
550 QLIST_INSERT_HEAD(&tg->head, tgm, round_robin);
552 throttle_timers_init(&tgm->throttle_timers,
553 tgm->aio_context,
554 tg->clock_type,
555 read_timer_cb,
556 write_timer_cb,
557 tgm);
558 qemu_co_mutex_init(&tgm->throttled_reqs_lock);
559 qemu_co_queue_init(&tgm->throttled_reqs[0]);
560 qemu_co_queue_init(&tgm->throttled_reqs[1]);
562 qemu_mutex_unlock(&tg->lock);
565 /* Unregister a ThrottleGroupMember from its group, removing it from the list,
566 * destroying the timers and setting the throttle_state pointer to NULL.
568 * The ThrottleGroupMember must not have pending throttled requests, so the
569 * caller has to drain them first.
571 * The group will be destroyed if it's empty after this operation.
573 * @tgm the ThrottleGroupMember to remove
575 void throttle_group_unregister_tgm(ThrottleGroupMember *tgm)
577 ThrottleState *ts = tgm->throttle_state;
578 ThrottleGroup *tg = container_of(ts, ThrottleGroup, ts);
579 ThrottleGroupMember *token;
580 int i;
582 if (!ts) {
583 /* Discard already unregistered tgm */
584 return;
587 qemu_mutex_lock(&tg->lock);
588 for (i = 0; i < 2; i++) {
589 assert(tgm->pending_reqs[i] == 0);
590 assert(qemu_co_queue_empty(&tgm->throttled_reqs[i]));
591 assert(!timer_pending(tgm->throttle_timers.timers[i]));
592 if (tg->tokens[i] == tgm) {
593 token = throttle_group_next_tgm(tgm);
594 /* Take care of the case where this is the last tgm in the group */
595 if (token == tgm) {
596 token = NULL;
598 tg->tokens[i] = token;
602 /* remove the current tgm from the list */
603 QLIST_REMOVE(tgm, round_robin);
604 throttle_timers_destroy(&tgm->throttle_timers);
605 qemu_mutex_unlock(&tg->lock);
607 throttle_group_unref(&tg->ts);
608 tgm->throttle_state = NULL;
611 void throttle_group_attach_aio_context(ThrottleGroupMember *tgm,
612 AioContext *new_context)
614 ThrottleTimers *tt = &tgm->throttle_timers;
615 throttle_timers_attach_aio_context(tt, new_context);
616 tgm->aio_context = new_context;
619 void throttle_group_detach_aio_context(ThrottleGroupMember *tgm)
621 ThrottleGroup *tg = container_of(tgm->throttle_state, ThrottleGroup, ts);
622 ThrottleTimers *tt = &tgm->throttle_timers;
623 int i;
625 /* Requests must have been drained */
626 assert(tgm->pending_reqs[0] == 0 && tgm->pending_reqs[1] == 0);
627 assert(qemu_co_queue_empty(&tgm->throttled_reqs[0]));
628 assert(qemu_co_queue_empty(&tgm->throttled_reqs[1]));
630 /* Kick off next ThrottleGroupMember, if necessary */
631 qemu_mutex_lock(&tg->lock);
632 for (i = 0; i < 2; i++) {
633 if (timer_pending(tt->timers[i])) {
634 tg->any_timer_armed[i] = false;
635 schedule_next_request(tgm, i);
638 qemu_mutex_unlock(&tg->lock);
640 throttle_timers_detach_aio_context(tt);
641 tgm->aio_context = NULL;
644 #undef THROTTLE_OPT_PREFIX
645 #define THROTTLE_OPT_PREFIX "x-"
647 /* Helper struct and array for QOM property setter/getter */
648 typedef struct {
649 const char *name;
650 BucketType type;
651 enum {
652 AVG,
653 MAX,
654 BURST_LENGTH,
655 IOPS_SIZE,
656 } category;
657 } ThrottleParamInfo;
659 static ThrottleParamInfo properties[] = {
661 THROTTLE_OPT_PREFIX QEMU_OPT_IOPS_TOTAL,
662 THROTTLE_OPS_TOTAL, AVG,
665 THROTTLE_OPT_PREFIX QEMU_OPT_IOPS_TOTAL_MAX,
666 THROTTLE_OPS_TOTAL, MAX,
669 THROTTLE_OPT_PREFIX QEMU_OPT_IOPS_TOTAL_MAX_LENGTH,
670 THROTTLE_OPS_TOTAL, BURST_LENGTH,
673 THROTTLE_OPT_PREFIX QEMU_OPT_IOPS_READ,
674 THROTTLE_OPS_READ, AVG,
677 THROTTLE_OPT_PREFIX QEMU_OPT_IOPS_READ_MAX,
678 THROTTLE_OPS_READ, MAX,
681 THROTTLE_OPT_PREFIX QEMU_OPT_IOPS_READ_MAX_LENGTH,
682 THROTTLE_OPS_READ, BURST_LENGTH,
685 THROTTLE_OPT_PREFIX QEMU_OPT_IOPS_WRITE,
686 THROTTLE_OPS_WRITE, AVG,
689 THROTTLE_OPT_PREFIX QEMU_OPT_IOPS_WRITE_MAX,
690 THROTTLE_OPS_WRITE, MAX,
693 THROTTLE_OPT_PREFIX QEMU_OPT_IOPS_WRITE_MAX_LENGTH,
694 THROTTLE_OPS_WRITE, BURST_LENGTH,
697 THROTTLE_OPT_PREFIX QEMU_OPT_BPS_TOTAL,
698 THROTTLE_BPS_TOTAL, AVG,
701 THROTTLE_OPT_PREFIX QEMU_OPT_BPS_TOTAL_MAX,
702 THROTTLE_BPS_TOTAL, MAX,
705 THROTTLE_OPT_PREFIX QEMU_OPT_BPS_TOTAL_MAX_LENGTH,
706 THROTTLE_BPS_TOTAL, BURST_LENGTH,
709 THROTTLE_OPT_PREFIX QEMU_OPT_BPS_READ,
710 THROTTLE_BPS_READ, AVG,
713 THROTTLE_OPT_PREFIX QEMU_OPT_BPS_READ_MAX,
714 THROTTLE_BPS_READ, MAX,
717 THROTTLE_OPT_PREFIX QEMU_OPT_BPS_READ_MAX_LENGTH,
718 THROTTLE_BPS_READ, BURST_LENGTH,
721 THROTTLE_OPT_PREFIX QEMU_OPT_BPS_WRITE,
722 THROTTLE_BPS_WRITE, AVG,
725 THROTTLE_OPT_PREFIX QEMU_OPT_BPS_WRITE_MAX,
726 THROTTLE_BPS_WRITE, MAX,
729 THROTTLE_OPT_PREFIX QEMU_OPT_BPS_WRITE_MAX_LENGTH,
730 THROTTLE_BPS_WRITE, BURST_LENGTH,
733 THROTTLE_OPT_PREFIX QEMU_OPT_IOPS_SIZE,
734 0, IOPS_SIZE,
738 /* This function edits throttle_groups and must be called under the global
739 * mutex */
740 static void throttle_group_obj_init(Object *obj)
742 ThrottleGroup *tg = THROTTLE_GROUP(obj);
744 tg->clock_type = QEMU_CLOCK_REALTIME;
745 if (qtest_enabled()) {
746 /* For testing block IO throttling only */
747 tg->clock_type = QEMU_CLOCK_VIRTUAL;
749 tg->is_initialized = false;
750 qemu_mutex_init(&tg->lock);
751 throttle_init(&tg->ts);
752 QLIST_INIT(&tg->head);
755 /* This function edits throttle_groups and must be called under the global
756 * mutex */
757 static void throttle_group_obj_complete(UserCreatable *obj, Error **errp)
759 ThrottleGroup *tg = THROTTLE_GROUP(obj);
760 ThrottleConfig cfg;
762 /* set group name to object id if it exists */
763 if (!tg->name && tg->parent_obj.parent) {
764 tg->name = object_get_canonical_path_component(OBJECT(obj));
766 /* We must have a group name at this point */
767 assert(tg->name);
769 /* error if name is duplicate */
770 if (throttle_group_exists(tg->name)) {
771 error_setg(errp, "A group with this name already exists");
772 return;
775 /* check validity */
776 throttle_get_config(&tg->ts, &cfg);
777 if (!throttle_is_valid(&cfg, errp)) {
778 return;
780 throttle_config(&tg->ts, tg->clock_type, &cfg);
781 QTAILQ_INSERT_TAIL(&throttle_groups, tg, list);
782 tg->is_initialized = true;
785 /* This function edits throttle_groups and must be called under the global
786 * mutex */
787 static void throttle_group_obj_finalize(Object *obj)
789 ThrottleGroup *tg = THROTTLE_GROUP(obj);
790 if (tg->is_initialized) {
791 QTAILQ_REMOVE(&throttle_groups, tg, list);
793 qemu_mutex_destroy(&tg->lock);
794 g_free(tg->name);
797 static void throttle_group_set(Object *obj, Visitor *v, const char * name,
798 void *opaque, Error **errp)
801 ThrottleGroup *tg = THROTTLE_GROUP(obj);
802 ThrottleConfig *cfg;
803 ThrottleParamInfo *info = opaque;
804 Error *local_err = NULL;
805 int64_t value;
807 /* If we have finished initialization, don't accept individual property
808 * changes through QOM. Throttle configuration limits must be set in one
809 * transaction, as certain combinations are invalid.
811 if (tg->is_initialized) {
812 error_setg(&local_err, "Property cannot be set after initialization");
813 goto ret;
816 visit_type_int64(v, name, &value, &local_err);
817 if (local_err) {
818 goto ret;
820 if (value < 0) {
821 error_setg(&local_err, "Property values cannot be negative");
822 goto ret;
825 cfg = &tg->ts.cfg;
826 switch (info->category) {
827 case AVG:
828 cfg->buckets[info->type].avg = value;
829 break;
830 case MAX:
831 cfg->buckets[info->type].max = value;
832 break;
833 case BURST_LENGTH:
834 if (value > UINT_MAX) {
835 error_setg(&local_err, "%s value must be in the"
836 "range [0, %u]", info->name, UINT_MAX);
837 goto ret;
839 cfg->buckets[info->type].burst_length = value;
840 break;
841 case IOPS_SIZE:
842 cfg->op_size = value;
843 break;
846 ret:
847 error_propagate(errp, local_err);
848 return;
852 static void throttle_group_get(Object *obj, Visitor *v, const char *name,
853 void *opaque, Error **errp)
855 ThrottleGroup *tg = THROTTLE_GROUP(obj);
856 ThrottleConfig cfg;
857 ThrottleParamInfo *info = opaque;
858 int64_t value;
860 throttle_get_config(&tg->ts, &cfg);
861 switch (info->category) {
862 case AVG:
863 value = cfg.buckets[info->type].avg;
864 break;
865 case MAX:
866 value = cfg.buckets[info->type].max;
867 break;
868 case BURST_LENGTH:
869 value = cfg.buckets[info->type].burst_length;
870 break;
871 case IOPS_SIZE:
872 value = cfg.op_size;
873 break;
876 visit_type_int64(v, name, &value, errp);
879 static void throttle_group_set_limits(Object *obj, Visitor *v,
880 const char *name, void *opaque,
881 Error **errp)
884 ThrottleGroup *tg = THROTTLE_GROUP(obj);
885 ThrottleConfig cfg;
886 ThrottleLimits arg = { 0 };
887 ThrottleLimits *argp = &arg;
888 Error *local_err = NULL;
890 visit_type_ThrottleLimits(v, name, &argp, &local_err);
891 if (local_err) {
892 goto ret;
894 qemu_mutex_lock(&tg->lock);
895 throttle_get_config(&tg->ts, &cfg);
896 throttle_limits_to_config(argp, &cfg, &local_err);
897 if (local_err) {
898 goto unlock;
900 throttle_config(&tg->ts, tg->clock_type, &cfg);
902 unlock:
903 qemu_mutex_unlock(&tg->lock);
904 ret:
905 error_propagate(errp, local_err);
906 return;
909 static void throttle_group_get_limits(Object *obj, Visitor *v,
910 const char *name, void *opaque,
911 Error **errp)
913 ThrottleGroup *tg = THROTTLE_GROUP(obj);
914 ThrottleConfig cfg;
915 ThrottleLimits arg = { 0 };
916 ThrottleLimits *argp = &arg;
918 qemu_mutex_lock(&tg->lock);
919 throttle_get_config(&tg->ts, &cfg);
920 qemu_mutex_unlock(&tg->lock);
922 throttle_config_to_limits(&cfg, argp);
924 visit_type_ThrottleLimits(v, name, &argp, errp);
927 static bool throttle_group_can_be_deleted(UserCreatable *uc)
929 return OBJECT(uc)->ref == 1;
932 static void throttle_group_obj_class_init(ObjectClass *klass, void *class_data)
934 size_t i = 0;
935 UserCreatableClass *ucc = USER_CREATABLE_CLASS(klass);
937 ucc->complete = throttle_group_obj_complete;
938 ucc->can_be_deleted = throttle_group_can_be_deleted;
940 /* individual properties */
941 for (i = 0; i < sizeof(properties) / sizeof(ThrottleParamInfo); i++) {
942 object_class_property_add(klass,
943 properties[i].name,
944 "int",
945 throttle_group_get,
946 throttle_group_set,
947 NULL, &properties[i],
948 &error_abort);
951 /* ThrottleLimits */
952 object_class_property_add(klass,
953 "limits", "ThrottleLimits",
954 throttle_group_get_limits,
955 throttle_group_set_limits,
956 NULL, NULL,
957 &error_abort);
960 static const TypeInfo throttle_group_info = {
961 .name = TYPE_THROTTLE_GROUP,
962 .parent = TYPE_OBJECT,
963 .class_init = throttle_group_obj_class_init,
964 .instance_size = sizeof(ThrottleGroup),
965 .instance_init = throttle_group_obj_init,
966 .instance_finalize = throttle_group_obj_finalize,
967 .interfaces = (InterfaceInfo[]) {
968 { TYPE_USER_CREATABLE },
973 static void throttle_groups_init(void)
975 type_register_static(&throttle_group_info);
978 type_init(throttle_groups_init);