diff --git a/blockjob.c b/blockjob.c index 715c2c2680..6173e4728c 100644 --- a/blockjob.c +++ b/blockjob.c @@ -59,6 +59,7 @@ static void __attribute__((__constructor__)) block_job_init(void) static void block_job_event_cancelled(BlockJob *job); static void block_job_event_completed(BlockJob *job, const char *msg); +static void block_job_enter_cond(BlockJob *job, bool(*fn)(BlockJob *job)); /* Transactional group of block jobs */ struct BlockJobTxn { @@ -480,9 +481,16 @@ static void block_job_completed_txn_success(BlockJob *job) } } +/* Assumes the block_job_mutex is held */ +static bool block_job_timer_pending(BlockJob *job) +{ + return timer_pending(&job->sleep_timer); +} + void block_job_set_speed(BlockJob *job, int64_t speed, Error **errp) { Error *local_err = NULL; + int64_t old_speed = job->speed; if (!job->driver->set_speed) { error_setg(errp, QERR_UNSUPPORTED); @@ -495,6 +503,12 @@ void block_job_set_speed(BlockJob *job, int64_t speed, Error **errp) } job->speed = speed; + if (speed <= old_speed) { + return; + } + + /* kick only if a timer is pending */ + block_job_enter_cond(job, block_job_timer_pending); } void block_job_complete(BlockJob *job, Error **errp) @@ -821,7 +835,11 @@ void block_job_resume_all(void) } } -void block_job_enter(BlockJob *job) +/* + * Conditionally enter a block_job pending a call to fn() while + * under the block_job_lock critical section. + */ +static void block_job_enter_cond(BlockJob *job, bool(*fn)(BlockJob *job)) { if (!block_job_started(job)) { return; @@ -836,6 +854,11 @@ void block_job_enter(BlockJob *job) return; } + if (fn && !fn(job)) { + block_job_unlock(); + return; + } + assert(!job->deferred_to_main_loop); timer_del(&job->sleep_timer); job->busy = true; @@ -843,6 +866,11 @@ void block_job_enter(BlockJob *job) aio_co_wake(job->co); } +void block_job_enter(BlockJob *job) +{ + block_job_enter_cond(job, NULL); +} + bool block_job_is_cancelled(BlockJob *job) { return job->cancelled;