@@ -37,7 +37,7 @@ typedef struct ThrottleGroupMember {
AioContext *aio_context;
/* throttled_reqs_lock protects the CoQueues for throttled requests. */
CoMutex throttled_reqs_lock;
- CoQueue throttled_reqs[2];
+ CoQueue throttled_reqs[THROTTLE_MAX];
/* Nonzero if the I/O limits are currently being ignored; generally
* it is zero. Accessed with atomic operations.
@@ -54,7 +54,7 @@ typedef struct ThrottleGroupMember {
* throttle_state tells us if I/O limits are configured. */
ThrottleState *throttle_state;
ThrottleTimers throttle_timers;
- unsigned pending_reqs[2];
+ unsigned pending_reqs[THROTTLE_MAX];
QLIST_ENTRY(ThrottleGroupMember) round_robin;
} ThrottleGroupMember;
@@ -78,7 +78,7 @@ void throttle_group_restart_tgm(ThrottleGroupMember *tgm);
void coroutine_fn throttle_group_co_io_limits_intercept(ThrottleGroupMember *tgm,
int64_t bytes,
- bool is_write);
+ ThrottleDirection direction);
void throttle_group_attach_aio_context(ThrottleGroupMember *tgm,
AioContext *new_context);
void throttle_group_detach_aio_context(ThrottleGroupMember *tgm);
@@ -1341,7 +1341,7 @@ blk_co_do_preadv_part(BlockBackend *blk, int64_t offset, int64_t bytes,
/* throttling disk I/O */
if (blk->public.throttle_group_member.throttle_state) {
throttle_group_co_io_limits_intercept(&blk->public.throttle_group_member,
- bytes, false);
+ bytes, THROTTLE_READ);
}
ret = bdrv_co_preadv_part(blk->root, offset, bytes, qiov, qiov_offset,
@@ -1415,7 +1415,7 @@ blk_co_do_pwritev_part(BlockBackend *blk, int64_t offset, int64_t bytes,
/* throttling disk I/O */
if (blk->public.throttle_group_member.throttle_state) {
throttle_group_co_io_limits_intercept(&blk->public.throttle_group_member,
- bytes, true);
+ bytes, THROTTLE_WRITE);
}
if (!blk->enable_write_cache) {
@@ -37,7 +37,7 @@
static void throttle_group_obj_init(Object *obj);
static void throttle_group_obj_complete(UserCreatable *obj, Error **errp);
-static void timer_cb(ThrottleGroupMember *tgm, bool is_write);
+static void timer_cb(ThrottleGroupMember *tgm, ThrottleDirection direction);
/* The ThrottleGroup structure (with its ThrottleState) is shared
* among different ThrottleGroupMembers and it's independent from
@@ -73,8 +73,8 @@ struct ThrottleGroup {
QemuMutex lock; /* This lock protects the following four fields */
ThrottleState ts;
QLIST_HEAD(, ThrottleGroupMember) head;
- ThrottleGroupMember *tokens[2];
- bool any_timer_armed[2];
+ ThrottleGroupMember *tokens[THROTTLE_MAX];
+ bool any_timer_armed[THROTTLE_MAX];
QEMUClockType clock_type;
/* This field is protected by the global QEMU mutex */
@@ -197,13 +197,13 @@ static ThrottleGroupMember *throttle_group_next_tgm(ThrottleGroupMember *tgm)
* This assumes that tg->lock is held.
*
* @tgm: the ThrottleGroupMember
- * @is_write: the type of operation (read/write)
+ * @direction: the ThrottleDirection
* @ret: whether the ThrottleGroupMember has pending requests.
*/
static inline bool tgm_has_pending_reqs(ThrottleGroupMember *tgm,
- bool is_write)
+ ThrottleDirection direction)
{
- return tgm->pending_reqs[is_write];
+ return tgm->pending_reqs[direction];
}
/* Return the next ThrottleGroupMember in the round-robin sequence with pending
@@ -212,12 +212,12 @@ static inline bool tgm_has_pending_reqs(ThrottleGroupMember *tgm,
* This assumes that tg->lock is held.
*
* @tgm: the current ThrottleGroupMember
- * @is_write: the type of operation (read/write)
+ * @direction: the ThrottleDirection
* @ret: the next ThrottleGroupMember with pending requests, or tgm if
* there is none.
*/
static ThrottleGroupMember *next_throttle_token(ThrottleGroupMember *tgm,
- bool is_write)
+ ThrottleDirection direction)
{
ThrottleState *ts = tgm->throttle_state;
ThrottleGroup *tg = container_of(ts, ThrottleGroup, ts);
@@ -227,16 +227,16 @@ static ThrottleGroupMember *next_throttle_token(ThrottleGroupMember *tgm,
* 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, is_write) &&
+ if (tgm_has_pending_reqs(tgm, direction) &&
qatomic_read(&tgm->io_limits_disabled)) {
return tgm;
}
- start = token = tg->tokens[is_write];
+ 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, is_write)) {
+ while (token != start && !tgm_has_pending_reqs(token, direction)) {
token = throttle_group_next_tgm(token);
}
@@ -244,12 +244,12 @@ static ThrottleGroupMember *next_throttle_token(ThrottleGroupMember *tgm,
* 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, is_write)) {
+ 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, is_write));
+ assert(token == tgm || tgm_has_pending_reqs(token, direction));
return token;
}
@@ -261,16 +261,15 @@ static ThrottleGroupMember *next_throttle_token(ThrottleGroupMember *tgm,
* This assumes that tg->lock is held.
*
* @tgm: the current ThrottleGroupMember
- * @is_write: the type of operation (read/write)
+ * @direction: the ThrottleDirection
* @ret: whether the I/O request needs to be throttled or not
*/
static bool throttle_group_schedule_timer(ThrottleGroupMember *tgm,
- bool is_write)
+ ThrottleDirection direction)
{
ThrottleState *ts = tgm->throttle_state;
ThrottleGroup *tg = container_of(ts, ThrottleGroup, ts);
ThrottleTimers *tt = &tgm->throttle_timers;
- ThrottleDirection direction = is_write ? THROTTLE_WRITE : THROTTLE_READ;
bool must_wait;
if (qatomic_read(&tgm->io_limits_disabled)) {
@@ -278,7 +277,7 @@ static bool throttle_group_schedule_timer(ThrottleGroupMember *tgm,
}
/* Check if any of the timers in this group is already armed */
- if (tg->any_timer_armed[is_write]) {
+ if (tg->any_timer_armed[direction]) {
return true;
}
@@ -286,8 +285,8 @@ static bool throttle_group_schedule_timer(ThrottleGroupMember *tgm,
/* If a timer just got armed, set tgm as the current token */
if (must_wait) {
- tg->tokens[is_write] = tgm;
- tg->any_timer_armed[is_write] = true;
+ tg->tokens[direction] = tgm;
+ tg->any_timer_armed[direction] = true;
}
return must_wait;
@@ -297,15 +296,15 @@ static bool throttle_group_schedule_timer(ThrottleGroupMember *tgm,
* any request was actually pending.
*
* @tgm: the current ThrottleGroupMember
- * @is_write: the type of operation (read/write)
+ * @direction: the ThrottleDirection
*/
static bool coroutine_fn throttle_group_co_restart_queue(ThrottleGroupMember *tgm,
- bool is_write)
+ ThrottleDirection direction)
{
bool ret;
qemu_co_mutex_lock(&tgm->throttled_reqs_lock);
- ret = qemu_co_queue_next(&tgm->throttled_reqs[is_write]);
+ ret = qemu_co_queue_next(&tgm->throttled_reqs[direction]);
qemu_co_mutex_unlock(&tgm->throttled_reqs_lock);
return ret;
@@ -316,9 +315,10 @@ static bool coroutine_fn throttle_group_co_restart_queue(ThrottleGroupMember *tg
* This assumes that tg->lock is held.
*
* @tgm: the current ThrottleGroupMember
- * @is_write: the type of operation (read/write)
+ * @direction: the ThrottleDirection
*/
-static void schedule_next_request(ThrottleGroupMember *tgm, bool is_write)
+static void schedule_next_request(ThrottleGroupMember *tgm,
+ ThrottleDirection direction)
{
ThrottleState *ts = tgm->throttle_state;
ThrottleGroup *tg = container_of(ts, ThrottleGroup, ts);
@@ -326,27 +326,27 @@ static void schedule_next_request(ThrottleGroupMember *tgm, bool is_write)
ThrottleGroupMember *token;
/* Check if there's any pending request to schedule next */
- token = next_throttle_token(tgm, is_write);
- if (!tgm_has_pending_reqs(token, is_write)) {
+ 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, is_write);
+ 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, is_write)) {
+ 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[is_write], now);
- tg->any_timer_armed[is_write] = true;
+ timer_mod(tt->timers[direction], now);
+ tg->any_timer_armed[direction] = true;
}
- tg->tokens[is_write] = token;
+ tg->tokens[direction] = token;
}
}
@@ -356,49 +356,49 @@ static void schedule_next_request(ThrottleGroupMember *tgm, bool is_write)
*
* @tgm: the current ThrottleGroupMember
* @bytes: the number of bytes for this I/O
- * @is_write: the type of operation (read/write)
+ * @direction: the ThrottleDirection
*/
void coroutine_fn throttle_group_co_io_limits_intercept(ThrottleGroupMember *tgm,
int64_t bytes,
- bool is_write)
+ ThrottleDirection direction)
{
bool must_wait;
ThrottleGroupMember *token;
ThrottleGroup *tg = container_of(tgm->throttle_state, ThrottleGroup, ts);
- ThrottleDirection direction = is_write ? THROTTLE_WRITE : THROTTLE_READ;
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, is_write);
- must_wait = throttle_group_schedule_timer(token, is_write);
+ 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[is_write]) {
- tgm->pending_reqs[is_write]++;
+ 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[is_write],
+ 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[is_write]--;
+ 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, is_write);
+ schedule_next_request(tgm, direction);
qemu_mutex_unlock(&tg->lock);
}
typedef struct {
ThrottleGroupMember *tgm;
- bool is_write;
+ ThrottleDirection direction;
} RestartData;
static void coroutine_fn throttle_group_restart_queue_entry(void *opaque)
@@ -407,16 +407,16 @@ static void coroutine_fn throttle_group_restart_queue_entry(void *opaque)
ThrottleGroupMember *tgm = data->tgm;
ThrottleState *ts = tgm->throttle_state;
ThrottleGroup *tg = container_of(ts, ThrottleGroup, ts);
- bool is_write = data->is_write;
+ ThrottleDirection direction = data->direction;
bool empty_queue;
- empty_queue = !throttle_group_co_restart_queue(tgm, is_write);
+ 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, is_write);
+ schedule_next_request(tgm, direction);
qemu_mutex_unlock(&tg->lock);
}
@@ -426,18 +426,19 @@ static void coroutine_fn throttle_group_restart_queue_entry(void *opaque)
aio_wait_kick();
}
-static void throttle_group_restart_queue(ThrottleGroupMember *tgm, bool is_write)
+static void throttle_group_restart_queue(ThrottleGroupMember *tgm,
+ ThrottleDirection direction)
{
Coroutine *co;
RestartData *rd = g_new0(RestartData, 1);
rd->tgm = tgm;
- rd->is_write = is_write;
+ 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[is_write]));
+ assert(!timer_pending(tgm->throttle_timers.timers[direction]));
qatomic_inc(&tgm->restart_pending);
@@ -447,18 +448,18 @@ static void throttle_group_restart_queue(ThrottleGroupMember *tgm, bool is_write
void throttle_group_restart_tgm(ThrottleGroupMember *tgm)
{
- int i;
+ ThrottleDirection dir;
if (tgm->throttle_state) {
- for (i = 0; i < 2; i++) {
- QEMUTimer *t = tgm->throttle_timers.timers[i];
+ 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, i);
+ timer_cb(tgm, dir);
} else {
/* Else run the next request from the queue manually */
- throttle_group_restart_queue(tgm, i);
+ throttle_group_restart_queue(tgm, dir);
}
}
}
@@ -502,30 +503,30 @@ void throttle_group_get_config(ThrottleGroupMember *tgm, ThrottleConfig *cfg)
* because it had been throttled.
*
* @tgm: the ThrottleGroupMember whose request had been throttled
- * @is_write: the type of operation (read/write)
+ * @direction: the ThrottleDirection
*/
-static void timer_cb(ThrottleGroupMember *tgm, bool is_write)
+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[is_write] = false;
+ 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, is_write);
+ throttle_group_restart_queue(tgm, direction);
}
static void read_timer_cb(void *opaque)
{
- timer_cb(opaque, false);
+ timer_cb(opaque, THROTTLE_READ);
}
static void write_timer_cb(void *opaque)
{
- timer_cb(opaque, true);
+ timer_cb(opaque, THROTTLE_WRITE);
}
/* Register a ThrottleGroupMember from the throttling group, also initializing
@@ -543,7 +544,7 @@ void throttle_group_register_tgm(ThrottleGroupMember *tgm,
const char *groupname,
AioContext *ctx)
{
- int i;
+ ThrottleDirection dir;
ThrottleState *ts = throttle_group_incref(groupname);
ThrottleGroup *tg = container_of(ts, ThrottleGroup, ts);
@@ -553,10 +554,11 @@ void throttle_group_register_tgm(ThrottleGroupMember *tgm,
QEMU_LOCK_GUARD(&tg->lock);
/* If the ThrottleGroup is new set this ThrottleGroupMember as the token */
- for (i = 0; i < 2; i++) {
- if (!tg->tokens[i]) {
- tg->tokens[i] = tgm;
+ 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);
@@ -568,8 +570,6 @@ void throttle_group_register_tgm(ThrottleGroupMember *tgm,
write_timer_cb,
tgm);
qemu_co_mutex_init(&tgm->throttled_reqs_lock);
- qemu_co_queue_init(&tgm->throttled_reqs[0]);
- qemu_co_queue_init(&tgm->throttled_reqs[1]);
}
/* Unregister a ThrottleGroupMember from its group, removing it from the list,
@@ -587,7 +587,7 @@ void throttle_group_unregister_tgm(ThrottleGroupMember *tgm)
ThrottleState *ts = tgm->throttle_state;
ThrottleGroup *tg = container_of(ts, ThrottleGroup, ts);
ThrottleGroupMember *token;
- int i;
+ ThrottleDirection dir;
if (!ts) {
/* Discard already unregistered tgm */
@@ -598,17 +598,17 @@ void throttle_group_unregister_tgm(ThrottleGroupMember *tgm)
AIO_WAIT_WHILE(tgm->aio_context, qatomic_read(&tgm->restart_pending) > 0);
WITH_QEMU_LOCK_GUARD(&tg->lock) {
- for (i = 0; i < 2; i++) {
- assert(tgm->pending_reqs[i] == 0);
- assert(qemu_co_queue_empty(&tgm->throttled_reqs[i]));
- assert(!timer_pending(tgm->throttle_timers.timers[i]));
- if (tg->tokens[i] == tgm) {
+ 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[i] = token;
+ tg->tokens[dir] = token;
}
}
@@ -633,19 +633,20 @@ void throttle_group_detach_aio_context(ThrottleGroupMember *tgm)
{
ThrottleGroup *tg = container_of(tgm->throttle_state, ThrottleGroup, ts);
ThrottleTimers *tt = &tgm->throttle_timers;
- int i;
+ ThrottleDirection dir;
/* Requests must have been drained */
- assert(tgm->pending_reqs[0] == 0 && tgm->pending_reqs[1] == 0);
- assert(qemu_co_queue_empty(&tgm->throttled_reqs[0]));
- assert(qemu_co_queue_empty(&tgm->throttled_reqs[1]));
+ 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 (i = 0; i < 2; i++) {
- if (timer_pending(tt->timers[i])) {
- tg->any_timer_armed[i] = false;
- schedule_next_request(tgm, i);
+ 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);
}
}
}
@@ -118,7 +118,7 @@ throttle_co_preadv(BlockDriverState *bs, int64_t offset, int64_t bytes,
{
ThrottleGroupMember *tgm = bs->opaque;
- throttle_group_co_io_limits_intercept(tgm, bytes, false);
+ throttle_group_co_io_limits_intercept(tgm, bytes, THROTTLE_READ);
return bdrv_co_preadv(bs->file, offset, bytes, qiov, flags);
}
@@ -128,7 +128,7 @@ throttle_co_pwritev(BlockDriverState *bs, int64_t offset, int64_t bytes,
QEMUIOVector *qiov, BdrvRequestFlags flags)
{
ThrottleGroupMember *tgm = bs->opaque;
- throttle_group_co_io_limits_intercept(tgm, bytes, true);
+ throttle_group_co_io_limits_intercept(tgm, bytes, THROTTLE_WRITE);
return bdrv_co_pwritev(bs->file, offset, bytes, qiov, flags);
}
@@ -138,7 +138,7 @@ throttle_co_pwrite_zeroes(BlockDriverState *bs, int64_t offset, int64_t bytes,
BdrvRequestFlags flags)
{
ThrottleGroupMember *tgm = bs->opaque;
- throttle_group_co_io_limits_intercept(tgm, bytes, true);
+ throttle_group_co_io_limits_intercept(tgm, bytes, THROTTLE_WRITE);
return bdrv_co_pwrite_zeroes(bs->file, offset, bytes, flags);
}
@@ -147,7 +147,7 @@ static int coroutine_fn GRAPH_RDLOCK
throttle_co_pdiscard(BlockDriverState *bs, int64_t offset, int64_t bytes)
{
ThrottleGroupMember *tgm = bs->opaque;
- throttle_group_co_io_limits_intercept(tgm, bytes, true);
+ throttle_group_co_io_limits_intercept(tgm, bytes, THROTTLE_WRITE);
return bdrv_co_pdiscard(bs->file, offset, bytes);
}