| /* |
| * QEMU block throttling group infrastructure |
| * |
| * Copyright (C) Nodalink, EURL. 2014 |
| * Copyright (C) Igalia, S.L. 2015 |
| * |
| * Authors: |
| * Benoît Canet <benoit.canet@nodalink.com> |
| * Alberto Garcia <berto@igalia.com> |
| * |
| * This program is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU General Public License as |
| * published by the Free Software Foundation; either version 2 or |
| * (at your option) version 3 of the License. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program; if not, see <http://www.gnu.org/licenses/>. |
| */ |
| |
| #include "qemu/osdep.h" |
| #include "sysemu/block-backend.h" |
| #include "block/throttle-groups.h" |
| #include "qemu/throttle-options.h" |
| #include "qemu/main-loop.h" |
| #include "qemu/queue.h" |
| #include "qemu/thread.h" |
| #include "sysemu/qtest.h" |
| #include "qapi/error.h" |
| #include "qapi/qapi-visit-block-core.h" |
| #include "qom/object.h" |
| #include "qom/object_interfaces.h" |
| |
| static void throttle_group_obj_init(Object *obj); |
| static void throttle_group_obj_complete(UserCreatable *obj, Error **errp); |
| static void timer_cb(ThrottleGroupMember *tgm, ThrottleDirection direction); |
| |
| /* The ThrottleGroup structure (with its ThrottleState) is shared |
| * among different ThrottleGroupMembers and it's independent from |
| * AioContext, so in order to use it from different threads it needs |
| * its own locking. |
| * |
| * This locking is however handled internally in this file, so it's |
| * transparent to outside users. |
| * |
| * The whole ThrottleGroup structure is private and invisible to |
| * outside users, that only use it through its ThrottleState. |
| * |
| * In addition to the ThrottleGroup structure, ThrottleGroupMember has |
| * fields that need to be accessed by other members of the group and |
| * therefore also need to be protected by this lock. Once a |
| * ThrottleGroupMember is registered in a group those fields can be accessed |
| * by other threads any time. |
| * |
| * Again, all this is handled internally and is mostly transparent to |
| * the outside. The 'throttle_timers' field however has an additional |
| * constraint because it may be temporarily invalid (see for example |
| * blk_set_aio_context()). Therefore in this file a thread will |
| * access some other ThrottleGroupMember's timers only after verifying that |
| * that ThrottleGroupMember has throttled requests in the queue. |
| */ |
| struct ThrottleGroup { |
| Object parent_obj; |
| |
| /* refuse individual property change if initialization is complete */ |
| bool is_initialized; |
| char *name; /* This is constant during the lifetime of the group */ |
| |
| QemuMutex lock; /* This lock protects the following four fields */ |
| ThrottleState ts; |
| QLIST_HEAD(, ThrottleGroupMember) head; |
| ThrottleGroupMember *tokens[THROTTLE_MAX]; |
| bool any_timer_armed[THROTTLE_MAX]; |
| QEMUClockType clock_type; |
| |
| /* This field is protected by the global QEMU mutex */ |
| QTAILQ_ENTRY(ThrottleGroup) list; |
| }; |
| |
| /* This is protected by the global QEMU mutex */ |
| static QTAILQ_HEAD(, ThrottleGroup) throttle_groups = |
| QTAILQ_HEAD_INITIALIZER(throttle_groups); |
| |
| |
| /* This function reads throttle_groups and must be called under the global |
| * mutex. |
| */ |
| static ThrottleGroup *throttle_group_by_name(const char *name) |
| { |
| ThrottleGroup *iter; |
| |
| /* Look for an existing group with that name */ |
| QTAILQ_FOREACH(iter, &throttle_groups, list) { |
| if (!g_strcmp0(name, iter->name)) { |
| return iter; |
| } |
| } |
| |
| return NULL; |
| } |
| |
| /* This function reads throttle_groups and must be called under the global |
| * mutex. |
| */ |
| bool throttle_group_exists(const char *name) |
| { |
| return throttle_group_by_name(name) != NULL; |
| } |
| |
| /* Increments the reference count of a ThrottleGroup given its name. |
| * |
| * If no ThrottleGroup is found with the given name a new one is |
| * created. |
| * |
| * This function edits throttle_groups and must be called under the global |
| * mutex. |
| * |
| * @name: the name of the ThrottleGroup |
| * @ret: the ThrottleState member of the ThrottleGroup |
| */ |
| ThrottleState *throttle_group_incref(const char *name) |
| { |
| ThrottleGroup *tg = NULL; |
| |
| /* Look for an existing group with that name */ |
| tg = throttle_group_by_name(name); |
| |
| if (tg) { |
| object_ref(OBJECT(tg)); |
| } else { |
| /* Create a new one if not found */ |
| /* new ThrottleGroup obj will have a refcnt = 1 */ |
| tg = THROTTLE_GROUP(object_new(TYPE_THROTTLE_GROUP)); |
| tg->name = g_strdup(name); |
| throttle_group_obj_complete(USER_CREATABLE(tg), &error_abort); |
| } |
| |
| return &tg->ts; |
| } |
| |
| /* Decrease the reference count of a ThrottleGroup. |
| * |
| * When the reference count reaches zero the ThrottleGroup is |
| * destroyed. |
| * |
| * This function edits throttle_groups and must be called under the global |
| * mutex. |
| * |
| * @ts: The ThrottleGroup to unref, given by its ThrottleState member |
| */ |
| void throttle_group_unref(ThrottleState *ts) |
| { |
| ThrottleGroup *tg = container_of(ts, ThrottleGroup, ts); |
| object_unref(OBJECT(tg)); |
| } |
| |
| /* Get the name from a ThrottleGroupMember's group. The name (and the pointer) |
| * is guaranteed to remain constant during the lifetime of the group. |
| * |
| * @tgm: a ThrottleGroupMember |
| * @ret: the name of the group. |
| */ |
| const char *throttle_group_get_name(ThrottleGroupMember *tgm) |
| { |
| ThrottleGroup *tg = container_of(tgm->throttle_state, ThrottleGroup, ts); |
| return tg->name; |
| } |
| |
| /* Return the next ThrottleGroupMember in the round-robin sequence, simulating |
| * a circular list. |
| * |
| * This assumes that tg->lock is held. |
| * |
| * @tgm: the current ThrottleGroupMember |
| * @ret: the next ThrottleGroupMember in the sequence |
| */ |
| static ThrottleGroupMember *throttle_group_next_tgm(ThrottleGroupMember *tgm) |
| { |
| ThrottleState *ts = tgm->throttle_state; |
| ThrottleGroup *tg = container_of(ts, ThrottleGroup, ts); |
| ThrottleGroupMember *next = QLIST_NEXT(tgm, round_robin); |
| |
| if (!next) { |
| next = QLIST_FIRST(&tg->head); |
| } |
| |
| return next; |
| } |
| |
| /* |
| * Return whether a ThrottleGroupMember has pending requests. |
| * |
| * This assumes that tg->lock is held. |
| * |
| * @tgm: the ThrottleGroupMember |
| * @direction: the ThrottleDirection |
| * @ret: whether the ThrottleGroupMember has pending requests. |
| */ |
| static inline bool tgm_has_pending_reqs(ThrottleGroupMember *tgm, |
| ThrottleDirection direction) |
| { |
| return tgm->pending_reqs[direction]; |
| } |
| |
| /* Return the next ThrottleGroupMember in the round-robin sequence with pending |
| * I/O requests. |
| * |
| * This assumes that tg->lock is held. |
| * |
| * @tgm: the current ThrottleGroupMember |
| * @direction: the ThrottleDirection |
| * @ret: the next ThrottleGroupMember with pending requests, or tgm if |
| * there is none. |
| */ |
| static ThrottleGroupMember *next_throttle_token(ThrottleGroupMember *tgm, |
| ThrottleDirection direction) |
| { |
| ThrottleState *ts = tgm->throttle_state; |
| ThrottleGroup *tg = container_of(ts, ThrottleGroup, ts); |
| ThrottleGroupMember *token, *start; |
| |
| /* If this member has its I/O limits disabled then it means that |
| * it's being drained. Skip the round-robin search and return tgm |
| * immediately if it has pending requests. Otherwise we could be |
| * forcing it to wait for other member's throttled requests. */ |
| if (tgm_has_pending_reqs(tgm, direction) && |
| qatomic_read(&tgm->io_limits_disabled)) { |
| return tgm; |
| } |
| |
| start = token = tg->tokens[direction]; |
| |
| /* get next bs round in round robin style */ |
| token = throttle_group_next_tgm(token); |
| while (token != start && !tgm_has_pending_reqs(token, direction)) { |
| token = throttle_group_next_tgm(token); |
| } |
| |
| /* If no IO are queued for scheduling on the next round robin token |
| * then decide the token is the current tgm because chances are |
| * the current tgm got the current request queued. |
| */ |
| if (token == start && !tgm_has_pending_reqs(token, direction)) { |
| token = tgm; |
| } |
| |
| /* Either we return the original TGM, or one with pending requests */ |
| assert(token == tgm || tgm_has_pending_reqs(token, direction)); |
| |
| return token; |
| } |
| |
| /* Check if the next I/O request for a ThrottleGroupMember needs to be |
| * throttled or not. If there's no timer set in this group, set one and update |
| * the token accordingly. |
| * |
| * This assumes that tg->lock is held. |
| * |
| * @tgm: the current ThrottleGroupMember |
| * @direction: the ThrottleDirection |
| * @ret: whether the I/O request needs to be throttled or not |
| */ |
| static bool throttle_group_schedule_timer(ThrottleGroupMember *tgm, |
| ThrottleDirection direction) |
| { |
| ThrottleState *ts = tgm->throttle_state; |
| ThrottleGroup *tg = container_of(ts, ThrottleGroup, ts); |
| ThrottleTimers *tt = &tgm->throttle_timers; |
| bool must_wait; |
| |
| if (qatomic_read(&tgm->io_limits_disabled)) { |
| return false; |
| } |
| |
| /* Check if any of the timers in this group is already armed */ |
| if (tg->any_timer_armed[direction]) { |
| return true; |
| } |
| |
| must_wait = throttle_schedule_timer(ts, tt, direction); |
| |
| /* If a timer just got armed, set tgm as the current token */ |
| if (must_wait) { |
| tg->tokens[direction] = tgm; |
| tg->any_timer_armed[direction] = true; |
| } |
| |
| return must_wait; |
| } |
| |
| /* Start the next pending I/O request for a ThrottleGroupMember. Return whether |
| * any request was actually pending. |
| * |
| * @tgm: the current ThrottleGroupMember |
| * @direction: the ThrottleDirection |
| */ |
| static bool coroutine_fn throttle_group_co_restart_queue(ThrottleGroupMember *tgm, |
| ThrottleDirection direction) |
| { |
| bool ret; |
| |
| qemu_co_mutex_lock(&tgm->throttled_reqs_lock); |
| ret = qemu_co_queue_next(&tgm->throttled_reqs[direction]); |
| qemu_co_mutex_unlock(&tgm->throttled_reqs_lock); |
| |
| return ret; |
| } |
| |
| /* Look for the next pending I/O request and schedule it. |
| * |
| * This assumes that tg->lock is held. |
| * |
| * @tgm: the current ThrottleGroupMember |
| * @direction: the ThrottleDirection |
| */ |
| static void schedule_next_request(ThrottleGroupMember *tgm, |
| ThrottleDirection direction) |
| { |
| ThrottleState *ts = tgm->throttle_state; |
| ThrottleGroup *tg = container_of(ts, ThrottleGroup, ts); |
| bool must_wait; |
| ThrottleGroupMember *token; |
| |
| /* Check if there's any pending request to schedule next */ |
| token = next_throttle_token(tgm, direction); |
| if (!tgm_has_pending_reqs(token, direction)) { |
| return; |
| } |
| |
| /* Set a timer for the request if it needs to be throttled */ |
| must_wait = throttle_group_schedule_timer(token, direction); |
| |
| /* If it doesn't have to wait, queue it for immediate execution */ |
| if (!must_wait) { |
| /* Give preference to requests from the current tgm */ |
| if (qemu_in_coroutine() && |
| throttle_group_co_restart_queue(tgm, direction)) { |
| token = tgm; |
| } else { |
| ThrottleTimers *tt = &token->throttle_timers; |
| int64_t now = qemu_clock_get_ns(tg->clock_type); |
| timer_mod(tt->timers[direction], now); |
| tg->any_timer_armed[direction] = true; |
| } |
| tg->tokens[direction] = token; |
| } |
| } |
| |
| /* Check if an I/O request needs to be throttled, wait and set a timer |
| * if necessary, and schedule the next request using a round robin |
| * algorithm. |
| * |
| * @tgm: the current ThrottleGroupMember |
| * @bytes: the number of bytes for this I/O |
| * @direction: the ThrottleDirection |
| */ |
| void coroutine_fn throttle_group_co_io_limits_intercept(ThrottleGroupMember *tgm, |
| int64_t bytes, |
| ThrottleDirection direction) |
| { |
| bool must_wait; |
| ThrottleGroupMember *token; |
| ThrottleGroup *tg = container_of(tgm->throttle_state, ThrottleGroup, ts); |
| |
| assert(bytes >= 0); |
| assert(direction < THROTTLE_MAX); |
| |
| qemu_mutex_lock(&tg->lock); |
| |
| /* First we check if this I/O has to be throttled. */ |
| token = next_throttle_token(tgm, direction); |
| must_wait = throttle_group_schedule_timer(token, direction); |
| |
| /* Wait if there's a timer set or queued requests of this type */ |
| if (must_wait || tgm->pending_reqs[direction]) { |
| tgm->pending_reqs[direction]++; |
| qemu_mutex_unlock(&tg->lock); |
| qemu_co_mutex_lock(&tgm->throttled_reqs_lock); |
| qemu_co_queue_wait(&tgm->throttled_reqs[direction], |
| &tgm->throttled_reqs_lock); |
| qemu_co_mutex_unlock(&tgm->throttled_reqs_lock); |
| qemu_mutex_lock(&tg->lock); |
| tgm->pending_reqs[direction]--; |
| } |
| |
| /* The I/O will be executed, so do the accounting */ |
| throttle_account(tgm->throttle_state, direction, bytes); |
| |
| /* Schedule the next request */ |
| schedule_next_request(tgm, direction); |
| |
| qemu_mutex_unlock(&tg->lock); |
| } |
| |
| typedef struct { |
| ThrottleGroupMember *tgm; |
| ThrottleDirection direction; |
| } RestartData; |
| |
| static void coroutine_fn throttle_group_restart_queue_entry(void *opaque) |
| { |
| RestartData *data = opaque; |
| ThrottleGroupMember *tgm = data->tgm; |
| ThrottleState *ts = tgm->throttle_state; |
| ThrottleGroup *tg = container_of(ts, ThrottleGroup, ts); |
| ThrottleDirection direction = data->direction; |
| bool empty_queue; |
| |
| empty_queue = !throttle_group_co_restart_queue(tgm, direction); |
| |
| /* If the request queue was empty then we have to take care of |
| * scheduling the next one */ |
| if (empty_queue) { |
| qemu_mutex_lock(&tg->lock); |
| schedule_next_request(tgm, direction); |
| qemu_mutex_unlock(&tg->lock); |
| } |
| |
| g_free(data); |
| |
| qatomic_dec(&tgm->restart_pending); |
| aio_wait_kick(); |
| } |
| |
| static void throttle_group_restart_queue(ThrottleGroupMember *tgm, |
| ThrottleDirection direction) |
| { |
| Coroutine *co; |
| RestartData *rd = g_new0(RestartData, 1); |
| |
| rd->tgm = tgm; |
| rd->direction = direction; |
| |
| /* This function is called when a timer is fired or when |
| * throttle_group_restart_tgm() is called. Either way, there can |
| * be no timer pending on this tgm at this point */ |
| assert(!timer_pending(tgm->throttle_timers.timers[direction])); |
| |
| qatomic_inc(&tgm->restart_pending); |
| |
| co = qemu_coroutine_create(throttle_group_restart_queue_entry, rd); |
| aio_co_enter(tgm->aio_context, co); |
| } |
| |
| void throttle_group_restart_tgm(ThrottleGroupMember *tgm) |
| { |
| ThrottleDirection dir; |
| |
| if (tgm->throttle_state) { |
| for (dir = THROTTLE_READ; dir < THROTTLE_MAX; dir++) { |
| QEMUTimer *t = tgm->throttle_timers.timers[dir]; |
| if (timer_pending(t)) { |
| /* If there's a pending timer on this tgm, fire it now */ |
| timer_del(t); |
| timer_cb(tgm, dir); |
| } else { |
| /* Else run the next request from the queue manually */ |
| throttle_group_restart_queue(tgm, dir); |
| } |
| } |
| } |
| } |
| |
| /* Update the throttle configuration for a particular group. Similar |
| * to throttle_config(), but guarantees atomicity within the |
| * throttling group. |
| * |
| * @tgm: a ThrottleGroupMember that is a member of the group |
| * @cfg: the configuration to set |
| */ |
| void throttle_group_config(ThrottleGroupMember *tgm, ThrottleConfig *cfg) |
| { |
| ThrottleState *ts = tgm->throttle_state; |
| ThrottleGroup *tg = container_of(ts, ThrottleGroup, ts); |
| qemu_mutex_lock(&tg->lock); |
| throttle_config(ts, tg->clock_type, cfg); |
| qemu_mutex_unlock(&tg->lock); |
| |
| throttle_group_restart_tgm(tgm); |
| } |
| |
| /* Get the throttle configuration from a particular group. Similar to |
| * throttle_get_config(), but guarantees atomicity within the |
| * throttling group. |
| * |
| * @tgm: a ThrottleGroupMember that is a member of the group |
| * @cfg: the configuration will be written here |
| */ |
| void throttle_group_get_config(ThrottleGroupMember *tgm, ThrottleConfig *cfg) |
| { |
| ThrottleState *ts = tgm->throttle_state; |
| ThrottleGroup *tg = container_of(ts, ThrottleGroup, ts); |
| qemu_mutex_lock(&tg->lock); |
| throttle_get_config(ts, cfg); |
| qemu_mutex_unlock(&tg->lock); |
| } |
| |
| /* ThrottleTimers callback. This wakes up a request that was waiting |
| * because it had been throttled. |
| * |
| * @tgm: the ThrottleGroupMember whose request had been throttled |
| * @direction: the ThrottleDirection |
| */ |
| static void timer_cb(ThrottleGroupMember *tgm, ThrottleDirection direction) |
| { |
| ThrottleState *ts = tgm->throttle_state; |
| ThrottleGroup *tg = container_of(ts, ThrottleGroup, ts); |
| |
| /* The timer has just been fired, so we can update the flag */ |
| qemu_mutex_lock(&tg->lock); |
| tg->any_timer_armed[direction] = false; |
| qemu_mutex_unlock(&tg->lock); |
| |
| /* Run the request that was waiting for this timer */ |
| throttle_group_restart_queue(tgm, direction); |
| } |
| |
| static void read_timer_cb(void *opaque) |
| { |
| timer_cb(opaque, THROTTLE_READ); |
| } |
| |
| static void write_timer_cb(void *opaque) |
| { |
| timer_cb(opaque, THROTTLE_WRITE); |
| } |
| |
| /* Register a ThrottleGroupMember from the throttling group, also initializing |
| * its timers and updating its throttle_state pointer to point to it. If a |
| * throttling group with that name does not exist yet, it will be created. |
| * |
| * This function edits throttle_groups and must be called under the global |
| * mutex. |
| * |
| * @tgm: the ThrottleGroupMember to insert |
| * @groupname: the name of the group |
| * @ctx: the AioContext to use |
| */ |
| void throttle_group_register_tgm(ThrottleGroupMember *tgm, |
| const char *groupname, |
| AioContext *ctx) |
| { |
| ThrottleDirection dir; |
| ThrottleState *ts = throttle_group_incref(groupname); |
| ThrottleGroup *tg = container_of(ts, ThrottleGroup, ts); |
| |
| tgm->throttle_state = ts; |
| tgm->aio_context = ctx; |
| qatomic_set(&tgm->restart_pending, 0); |
| |
| QEMU_LOCK_GUARD(&tg->lock); |
| /* If the ThrottleGroup is new set this ThrottleGroupMember as the token */ |
| for (dir = THROTTLE_READ; dir < THROTTLE_MAX; dir++) { |
| if (!tg->tokens[dir]) { |
| tg->tokens[dir] = tgm; |
| } |
| qemu_co_queue_init(&tgm->throttled_reqs[dir]); |
| } |
| |
| QLIST_INSERT_HEAD(&tg->head, tgm, round_robin); |
| |
| throttle_timers_init(&tgm->throttle_timers, |
| tgm->aio_context, |
| tg->clock_type, |
| read_timer_cb, |
| write_timer_cb, |
| tgm); |
| qemu_co_mutex_init(&tgm->throttled_reqs_lock); |
| } |
| |
| /* Unregister a ThrottleGroupMember from its group, removing it from the list, |
| * destroying the timers and setting the throttle_state pointer to NULL. |
| * |
| * The ThrottleGroupMember must not have pending throttled requests, so the |
| * caller has to drain them first. |
| * |
| * The group will be destroyed if it's empty after this operation. |
| * |
| * @tgm the ThrottleGroupMember to remove |
| */ |
| void throttle_group_unregister_tgm(ThrottleGroupMember *tgm) |
| { |
| ThrottleState *ts = tgm->throttle_state; |
| ThrottleGroup *tg = container_of(ts, ThrottleGroup, ts); |
| ThrottleGroupMember *token; |
| ThrottleDirection dir; |
| |
| if (!ts) { |
| /* Discard already unregistered tgm */ |
| return; |
| } |
| |
| /* Wait for throttle_group_restart_queue_entry() coroutines to finish */ |
| AIO_WAIT_WHILE(tgm->aio_context, qatomic_read(&tgm->restart_pending) > 0); |
| |
| WITH_QEMU_LOCK_GUARD(&tg->lock) { |
| for (dir = THROTTLE_READ; dir < THROTTLE_MAX; dir++) { |
| assert(tgm->pending_reqs[dir] == 0); |
| assert(qemu_co_queue_empty(&tgm->throttled_reqs[dir])); |
| assert(!timer_pending(tgm->throttle_timers.timers[dir])); |
| if (tg->tokens[dir] == tgm) { |
| token = throttle_group_next_tgm(tgm); |
| /* Take care of the case where this is the last tgm in the group */ |
| if (token == tgm) { |
| token = NULL; |
| } |
| tg->tokens[dir] = token; |
| } |
| } |
| |
| /* remove the current tgm from the list */ |
| QLIST_REMOVE(tgm, round_robin); |
| throttle_timers_destroy(&tgm->throttle_timers); |
| } |
| |
| throttle_group_unref(&tg->ts); |
| tgm->throttle_state = NULL; |
| } |
| |
| void throttle_group_attach_aio_context(ThrottleGroupMember *tgm, |
| AioContext *new_context) |
| { |
| ThrottleTimers *tt = &tgm->throttle_timers; |
| throttle_timers_attach_aio_context(tt, new_context); |
| tgm->aio_context = new_context; |
| } |
| |
| void throttle_group_detach_aio_context(ThrottleGroupMember *tgm) |
| { |
| ThrottleGroup *tg = container_of(tgm->throttle_state, ThrottleGroup, ts); |
| ThrottleTimers *tt = &tgm->throttle_timers; |
| ThrottleDirection dir; |
| |
| /* Requests must have been drained */ |
| for (dir = THROTTLE_READ; dir < THROTTLE_MAX; dir++) { |
| assert(tgm->pending_reqs[dir] == 0); |
| assert(qemu_co_queue_empty(&tgm->throttled_reqs[dir])); |
| } |
| |
| /* Kick off next ThrottleGroupMember, if necessary */ |
| WITH_QEMU_LOCK_GUARD(&tg->lock) { |
| for (dir = THROTTLE_READ; dir < THROTTLE_MAX; dir++) { |
| if (timer_pending(tt->timers[dir])) { |
| tg->any_timer_armed[dir] = false; |
| schedule_next_request(tgm, dir); |
| } |
| } |
| } |
| |
| throttle_timers_detach_aio_context(tt); |
| tgm->aio_context = NULL; |
| } |
| |
| #undef THROTTLE_OPT_PREFIX |
| #define THROTTLE_OPT_PREFIX "x-" |
| |
| /* Helper struct and array for QOM property setter/getter */ |
| typedef struct { |
| const char *name; |
| BucketType type; |
| enum { |
| AVG, |
| MAX, |
| BURST_LENGTH, |
| IOPS_SIZE, |
| } category; |
| } ThrottleParamInfo; |
| |
| static ThrottleParamInfo properties[] = { |
| { |
| THROTTLE_OPT_PREFIX QEMU_OPT_IOPS_TOTAL, |
| THROTTLE_OPS_TOTAL, AVG, |
| }, |
| { |
| THROTTLE_OPT_PREFIX QEMU_OPT_IOPS_TOTAL_MAX, |
| THROTTLE_OPS_TOTAL, MAX, |
| }, |
| { |
| THROTTLE_OPT_PREFIX QEMU_OPT_IOPS_TOTAL_MAX_LENGTH, |
| THROTTLE_OPS_TOTAL, BURST_LENGTH, |
| }, |
| { |
| THROTTLE_OPT_PREFIX QEMU_OPT_IOPS_READ, |
| THROTTLE_OPS_READ, AVG, |
| }, |
| { |
| THROTTLE_OPT_PREFIX QEMU_OPT_IOPS_READ_MAX, |
| THROTTLE_OPS_READ, MAX, |
| }, |
| { |
| THROTTLE_OPT_PREFIX QEMU_OPT_IOPS_READ_MAX_LENGTH, |
| THROTTLE_OPS_READ, BURST_LENGTH, |
| }, |
| { |
| THROTTLE_OPT_PREFIX QEMU_OPT_IOPS_WRITE, |
| THROTTLE_OPS_WRITE, AVG, |
| }, |
| { |
| THROTTLE_OPT_PREFIX QEMU_OPT_IOPS_WRITE_MAX, |
| THROTTLE_OPS_WRITE, MAX, |
| }, |
| { |
| THROTTLE_OPT_PREFIX QEMU_OPT_IOPS_WRITE_MAX_LENGTH, |
| THROTTLE_OPS_WRITE, BURST_LENGTH, |
| }, |
| { |
| THROTTLE_OPT_PREFIX QEMU_OPT_BPS_TOTAL, |
| THROTTLE_BPS_TOTAL, AVG, |
| }, |
| { |
| THROTTLE_OPT_PREFIX QEMU_OPT_BPS_TOTAL_MAX, |
| THROTTLE_BPS_TOTAL, MAX, |
| }, |
| { |
| THROTTLE_OPT_PREFIX QEMU_OPT_BPS_TOTAL_MAX_LENGTH, |
| THROTTLE_BPS_TOTAL, BURST_LENGTH, |
| }, |
| { |
| THROTTLE_OPT_PREFIX QEMU_OPT_BPS_READ, |
| THROTTLE_BPS_READ, AVG, |
| }, |
| { |
| THROTTLE_OPT_PREFIX QEMU_OPT_BPS_READ_MAX, |
| THROTTLE_BPS_READ, MAX, |
| }, |
| { |
| THROTTLE_OPT_PREFIX QEMU_OPT_BPS_READ_MAX_LENGTH, |
| THROTTLE_BPS_READ, BURST_LENGTH, |
| }, |
| { |
| THROTTLE_OPT_PREFIX QEMU_OPT_BPS_WRITE, |
| THROTTLE_BPS_WRITE, AVG, |
| }, |
| { |
| THROTTLE_OPT_PREFIX QEMU_OPT_BPS_WRITE_MAX, |
| THROTTLE_BPS_WRITE, MAX, |
| }, |
| { |
| THROTTLE_OPT_PREFIX QEMU_OPT_BPS_WRITE_MAX_LENGTH, |
| THROTTLE_BPS_WRITE, BURST_LENGTH, |
| }, |
| { |
| THROTTLE_OPT_PREFIX QEMU_OPT_IOPS_SIZE, |
| 0, IOPS_SIZE, |
| } |
| }; |
| |
| /* This function edits throttle_groups and must be called under the global |
| * mutex */ |
| static void throttle_group_obj_init(Object *obj) |
| { |
| ThrottleGroup *tg = THROTTLE_GROUP(obj); |
| |
| tg->clock_type = QEMU_CLOCK_REALTIME; |
| if (qtest_enabled()) { |
| /* For testing block IO throttling only */ |
| tg->clock_type = QEMU_CLOCK_VIRTUAL; |
| } |
| tg->is_initialized = false; |
| qemu_mutex_init(&tg->lock); |
| throttle_init(&tg->ts); |
| QLIST_INIT(&tg->head); |
| } |
| |
| /* This function edits throttle_groups and must be called under the global |
| * mutex */ |
| static void throttle_group_obj_complete(UserCreatable *obj, Error **errp) |
| { |
| ThrottleGroup *tg = THROTTLE_GROUP(obj); |
| ThrottleConfig cfg; |
| |
| /* set group name to object id if it exists */ |
| if (!tg->name && tg->parent_obj.parent) { |
| tg->name = g_strdup(object_get_canonical_path_component(OBJECT(obj))); |
| } |
| /* We must have a group name at this point */ |
| assert(tg->name); |
| |
| /* error if name is duplicate */ |
| if (throttle_group_exists(tg->name)) { |
| error_setg(errp, "A group with this name already exists"); |
| return; |
| } |
| |
| /* check validity */ |
| throttle_get_config(&tg->ts, &cfg); |
| if (!throttle_is_valid(&cfg, errp)) { |
| return; |
| } |
| throttle_config(&tg->ts, tg->clock_type, &cfg); |
| QTAILQ_INSERT_TAIL(&throttle_groups, tg, list); |
| tg->is_initialized = true; |
| } |
| |
| /* This function edits throttle_groups and must be called under the global |
| * mutex */ |
| static void throttle_group_obj_finalize(Object *obj) |
| { |
| ThrottleGroup *tg = THROTTLE_GROUP(obj); |
| if (tg->is_initialized) { |
| QTAILQ_REMOVE(&throttle_groups, tg, list); |
| } |
| qemu_mutex_destroy(&tg->lock); |
| g_free(tg->name); |
| } |
| |
| static void throttle_group_set(Object *obj, Visitor *v, const char * name, |
| void *opaque, Error **errp) |
| |
| { |
| ThrottleGroup *tg = THROTTLE_GROUP(obj); |
| ThrottleConfig *cfg; |
| ThrottleParamInfo *info = opaque; |
| int64_t value; |
| |
| /* If we have finished initialization, don't accept individual property |
| * changes through QOM. Throttle configuration limits must be set in one |
| * transaction, as certain combinations are invalid. |
| */ |
| if (tg->is_initialized) { |
| error_setg(errp, "Property cannot be set after initialization"); |
| return; |
| } |
| |
| if (!visit_type_int64(v, name, &value, errp)) { |
| return; |
| } |
| if (value < 0) { |
| error_setg(errp, "Property values cannot be negative"); |
| return; |
| } |
| |
| cfg = &tg->ts.cfg; |
| switch (info->category) { |
| case AVG: |
| cfg->buckets[info->type].avg = value; |
| break; |
| case MAX: |
| cfg->buckets[info->type].max = value; |
| break; |
| case BURST_LENGTH: |
| if (value > UINT_MAX) { |
| error_setg(errp, "%s value must be in the" "range [0, %u]", |
| info->name, UINT_MAX); |
| return; |
| } |
| cfg->buckets[info->type].burst_length = value; |
| break; |
| case IOPS_SIZE: |
| cfg->op_size = value; |
| break; |
| } |
| } |
| |
| static void throttle_group_get(Object *obj, Visitor *v, const char *name, |
| void *opaque, Error **errp) |
| { |
| ThrottleGroup *tg = THROTTLE_GROUP(obj); |
| ThrottleConfig cfg; |
| ThrottleParamInfo *info = opaque; |
| int64_t value; |
| |
| throttle_get_config(&tg->ts, &cfg); |
| switch (info->category) { |
| case AVG: |
| value = cfg.buckets[info->type].avg; |
| break; |
| case MAX: |
| value = cfg.buckets[info->type].max; |
| break; |
| case BURST_LENGTH: |
| value = cfg.buckets[info->type].burst_length; |
| break; |
| case IOPS_SIZE: |
| value = cfg.op_size; |
| break; |
| } |
| |
| visit_type_int64(v, name, &value, errp); |
| } |
| |
| static void throttle_group_set_limits(Object *obj, Visitor *v, |
| const char *name, void *opaque, |
| Error **errp) |
| |
| { |
| ThrottleGroup *tg = THROTTLE_GROUP(obj); |
| ThrottleConfig cfg; |
| ThrottleLimits *argp; |
| Error *local_err = NULL; |
| |
| if (!visit_type_ThrottleLimits(v, name, &argp, errp)) { |
| return; |
| } |
| qemu_mutex_lock(&tg->lock); |
| throttle_get_config(&tg->ts, &cfg); |
| throttle_limits_to_config(argp, &cfg, &local_err); |
| if (local_err) { |
| goto unlock; |
| } |
| throttle_config(&tg->ts, tg->clock_type, &cfg); |
| |
| unlock: |
| qemu_mutex_unlock(&tg->lock); |
| qapi_free_ThrottleLimits(argp); |
| error_propagate(errp, local_err); |
| return; |
| } |
| |
| static void throttle_group_get_limits(Object *obj, Visitor *v, |
| const char *name, void *opaque, |
| Error **errp) |
| { |
| ThrottleGroup *tg = THROTTLE_GROUP(obj); |
| ThrottleConfig cfg; |
| ThrottleLimits arg = { 0 }; |
| ThrottleLimits *argp = &arg; |
| |
| qemu_mutex_lock(&tg->lock); |
| throttle_get_config(&tg->ts, &cfg); |
| qemu_mutex_unlock(&tg->lock); |
| |
| throttle_config_to_limits(&cfg, argp); |
| |
| visit_type_ThrottleLimits(v, name, &argp, errp); |
| } |
| |
| static bool throttle_group_can_be_deleted(UserCreatable *uc) |
| { |
| return OBJECT(uc)->ref == 1; |
| } |
| |
| static void throttle_group_obj_class_init(ObjectClass *klass, void *class_data) |
| { |
| size_t i = 0; |
| UserCreatableClass *ucc = USER_CREATABLE_CLASS(klass); |
| |
| ucc->complete = throttle_group_obj_complete; |
| ucc->can_be_deleted = throttle_group_can_be_deleted; |
| |
| /* individual properties */ |
| for (i = 0; i < sizeof(properties) / sizeof(ThrottleParamInfo); i++) { |
| object_class_property_add(klass, |
| properties[i].name, |
| "int", |
| throttle_group_get, |
| throttle_group_set, |
| NULL, &properties[i]); |
| } |
| |
| /* ThrottleLimits */ |
| object_class_property_add(klass, |
| "limits", "ThrottleLimits", |
| throttle_group_get_limits, |
| throttle_group_set_limits, |
| NULL, NULL); |
| } |
| |
| static const TypeInfo throttle_group_info = { |
| .name = TYPE_THROTTLE_GROUP, |
| .parent = TYPE_OBJECT, |
| .class_init = throttle_group_obj_class_init, |
| .instance_size = sizeof(ThrottleGroup), |
| .instance_init = throttle_group_obj_init, |
| .instance_finalize = throttle_group_obj_finalize, |
| .interfaces = (InterfaceInfo[]) { |
| { TYPE_USER_CREATABLE }, |
| { } |
| }, |
| }; |
| |
| static void throttle_groups_init(void) |
| { |
| type_register_static(&throttle_group_info); |
| } |
| |
| type_init(throttle_groups_init); |
