diff --git a/block/blk-core.c b/block/blk-core.c index 2f4002f79a24..518dd423a5fe 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -352,7 +352,7 @@ void blk_start_queue(struct request_queue *q) WARN_ON(!irqs_disabled()); queue_flag_clear(QUEUE_FLAG_STOPPED, q); - __blk_run_queue(q); + __blk_run_queue(q, false); } EXPORT_SYMBOL(blk_start_queue); @@ -403,13 +403,14 @@ EXPORT_SYMBOL(blk_sync_queue); /** * __blk_run_queue - run a single device queue * @q: The queue to run + * @force_kblockd: Don't run @q->request_fn directly. Use kblockd. * * Description: * See @blk_run_queue. This variant must be called with the queue lock * held and interrupts disabled. * */ -void __blk_run_queue(struct request_queue *q) +void __blk_run_queue(struct request_queue *q, bool force_kblockd) { blk_remove_plug(q); @@ -423,7 +424,7 @@ void __blk_run_queue(struct request_queue *q) * Only recurse once to avoid overrunning the stack, let the unplug * handling reinvoke the handler shortly if we already got there. */ - if (!queue_flag_test_and_set(QUEUE_FLAG_REENTER, q)) { + if (!force_kblockd && !queue_flag_test_and_set(QUEUE_FLAG_REENTER, q)) { q->request_fn(q); queue_flag_clear(QUEUE_FLAG_REENTER, q); } else { @@ -446,7 +447,7 @@ void blk_run_queue(struct request_queue *q) unsigned long flags; spin_lock_irqsave(q->queue_lock, flags); - __blk_run_queue(q); + __blk_run_queue(q, false); spin_unlock_irqrestore(q->queue_lock, flags); } EXPORT_SYMBOL(blk_run_queue); @@ -1053,7 +1054,7 @@ void blk_insert_request(struct request_queue *q, struct request *rq, drive_stat_acct(rq, 1); __elv_add_request(q, rq, where, 0); - __blk_run_queue(q); + __blk_run_queue(q, false); spin_unlock_irqrestore(q->queue_lock, flags); } EXPORT_SYMBOL(blk_insert_request); @@ -2610,13 +2611,6 @@ int kblockd_schedule_work(struct request_queue *q, struct work_struct *work) } EXPORT_SYMBOL(kblockd_schedule_work); -int kblockd_schedule_delayed_work(struct request_queue *q, - struct delayed_work *dwork, unsigned long delay) -{ - return queue_delayed_work(kblockd_workqueue, dwork, delay); -} -EXPORT_SYMBOL(kblockd_schedule_delayed_work); - int __init blk_dev_init(void) { BUILD_BUG_ON(__REQ_NR_BITS > 8 * diff --git a/block/blk-flush.c b/block/blk-flush.c index 54b123d6563e..b27d0208611b 100644 --- a/block/blk-flush.c +++ b/block/blk-flush.c @@ -66,10 +66,12 @@ static void blk_flush_complete_seq_end_io(struct request_queue *q, /* * Moving a request silently to empty queue_head may stall the - * queue. Kick the queue in those cases. + * queue. Kick the queue in those cases. This function is called + * from request completion path and calling directly into + * request_fn may confuse the driver. Always use kblockd. */ if (was_empty && next_rq) - __blk_run_queue(q); + __blk_run_queue(q, true); } static void pre_flush_end_io(struct request *rq, int error) @@ -130,7 +132,7 @@ static struct request *queue_next_fseq(struct request_queue *q) BUG(); } - elv_insert(q, rq, ELEVATOR_INSERT_FRONT); + elv_insert(q, rq, ELEVATOR_INSERT_REQUEUE); return rq; } diff --git a/block/blk-lib.c b/block/blk-lib.c index 1a320d2406b0..eec78becb355 100644 --- a/block/blk-lib.c +++ b/block/blk-lib.c @@ -132,7 +132,7 @@ static void bio_batch_end_io(struct bio *bio, int err) } /** - * blkdev_issue_zeroout generate number of zero filed write bios + * blkdev_issue_zeroout - generate number of zero filed write bios * @bdev: blockdev to issue * @sector: start sector * @nr_sects: number of sectors to write diff --git a/block/blk-throttle.c b/block/blk-throttle.c index a89043a3caa4..e36cc10a346c 100644 --- a/block/blk-throttle.c +++ b/block/blk-throttle.c @@ -20,6 +20,11 @@ static int throtl_quantum = 32; /* Throttling is performed over 100ms slice and after that slice is renewed */ static unsigned long throtl_slice = HZ/10; /* 100 ms */ +/* A workqueue to queue throttle related work */ +static struct workqueue_struct *kthrotld_workqueue; +static void throtl_schedule_delayed_work(struct throtl_data *td, + unsigned long delay); + struct throtl_rb_root { struct rb_root rb; struct rb_node *left; @@ -345,10 +350,9 @@ static void throtl_schedule_next_dispatch(struct throtl_data *td) update_min_dispatch_time(st); if (time_before_eq(st->min_disptime, jiffies)) - throtl_schedule_delayed_work(td->queue, 0); + throtl_schedule_delayed_work(td, 0); else - throtl_schedule_delayed_work(td->queue, - (st->min_disptime - jiffies)); + throtl_schedule_delayed_work(td, (st->min_disptime - jiffies)); } static inline void @@ -815,10 +819,10 @@ void blk_throtl_work(struct work_struct *work) } /* Call with queue lock held */ -void throtl_schedule_delayed_work(struct request_queue *q, unsigned long delay) +static void +throtl_schedule_delayed_work(struct throtl_data *td, unsigned long delay) { - struct throtl_data *td = q->td; struct delayed_work *dwork = &td->throtl_work; if (total_nr_queued(td) > 0) { @@ -827,12 +831,11 @@ void throtl_schedule_delayed_work(struct request_queue *q, unsigned long delay) * Cancel that and schedule a new one. */ __cancel_delayed_work(dwork); - kblockd_schedule_delayed_work(q, dwork, delay); + queue_delayed_work(kthrotld_workqueue, dwork, delay); throtl_log(td, "schedule work. delay=%lu jiffies=%lu", delay, jiffies); } } -EXPORT_SYMBOL(throtl_schedule_delayed_work); static void throtl_destroy_tg(struct throtl_data *td, struct throtl_grp *tg) @@ -920,7 +923,7 @@ static void throtl_update_blkio_group_read_bps(void *key, smp_mb__after_atomic_inc(); /* Schedule a work now to process the limit change */ - throtl_schedule_delayed_work(td->queue, 0); + throtl_schedule_delayed_work(td, 0); } static void throtl_update_blkio_group_write_bps(void *key, @@ -934,7 +937,7 @@ static void throtl_update_blkio_group_write_bps(void *key, smp_mb__before_atomic_inc(); atomic_inc(&td->limits_changed); smp_mb__after_atomic_inc(); - throtl_schedule_delayed_work(td->queue, 0); + throtl_schedule_delayed_work(td, 0); } static void throtl_update_blkio_group_read_iops(void *key, @@ -948,7 +951,7 @@ static void throtl_update_blkio_group_read_iops(void *key, smp_mb__before_atomic_inc(); atomic_inc(&td->limits_changed); smp_mb__after_atomic_inc(); - throtl_schedule_delayed_work(td->queue, 0); + throtl_schedule_delayed_work(td, 0); } static void throtl_update_blkio_group_write_iops(void *key, @@ -962,7 +965,7 @@ static void throtl_update_blkio_group_write_iops(void *key, smp_mb__before_atomic_inc(); atomic_inc(&td->limits_changed); smp_mb__after_atomic_inc(); - throtl_schedule_delayed_work(td->queue, 0); + throtl_schedule_delayed_work(td, 0); } void throtl_shutdown_timer_wq(struct request_queue *q) @@ -1135,6 +1138,10 @@ void blk_throtl_exit(struct request_queue *q) static int __init throtl_init(void) { + kthrotld_workqueue = alloc_workqueue("kthrotld", WQ_MEM_RECLAIM, 0); + if (!kthrotld_workqueue) + panic("Failed to create kthrotld\n"); + blkio_policy_register(&blkio_policy_throtl); return 0; } diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c index 7be4c7959625..ea83a4f0c27d 100644 --- a/block/cfq-iosched.c +++ b/block/cfq-iosched.c @@ -3355,7 +3355,7 @@ cfq_rq_enqueued(struct cfq_data *cfqd, struct cfq_queue *cfqq, cfqd->busy_queues > 1) { cfq_del_timer(cfqd, cfqq); cfq_clear_cfqq_wait_request(cfqq); - __blk_run_queue(cfqd->queue); + __blk_run_queue(cfqd->queue, false); } else { cfq_blkiocg_update_idle_time_stats( &cfqq->cfqg->blkg); @@ -3370,7 +3370,7 @@ cfq_rq_enqueued(struct cfq_data *cfqd, struct cfq_queue *cfqq, * this new queue is RT and the current one is BE */ cfq_preempt_queue(cfqd, cfqq); - __blk_run_queue(cfqd->queue); + __blk_run_queue(cfqd->queue, false); } } @@ -3731,7 +3731,7 @@ static void cfq_kick_queue(struct work_struct *work) struct request_queue *q = cfqd->queue; spin_lock_irq(q->queue_lock); - __blk_run_queue(cfqd->queue); + __blk_run_queue(cfqd->queue, false); spin_unlock_irq(q->queue_lock); } diff --git a/block/elevator.c b/block/elevator.c index 2569512830d3..236e93c1f46c 100644 --- a/block/elevator.c +++ b/block/elevator.c @@ -602,7 +602,7 @@ void elv_quiesce_start(struct request_queue *q) */ elv_drain_elevator(q); while (q->rq.elvpriv) { - __blk_run_queue(q); + __blk_run_queue(q, false); spin_unlock_irq(q->queue_lock); msleep(10); spin_lock_irq(q->queue_lock); @@ -651,7 +651,7 @@ void elv_insert(struct request_queue *q, struct request *rq, int where) * with anything. There's no point in delaying queue * processing. */ - __blk_run_queue(q); + __blk_run_queue(q, false); break; case ELEVATOR_INSERT_SORT: diff --git a/drivers/block/loop.c b/drivers/block/loop.c index 49e6a545eb63..dbf31ec9114d 100644 --- a/drivers/block/loop.c +++ b/drivers/block/loop.c @@ -78,7 +78,6 @@ #include -static DEFINE_MUTEX(loop_mutex); static LIST_HEAD(loop_devices); static DEFINE_MUTEX(loop_devices_mutex); @@ -1501,11 +1500,9 @@ static int lo_open(struct block_device *bdev, fmode_t mode) { struct loop_device *lo = bdev->bd_disk->private_data; - mutex_lock(&loop_mutex); mutex_lock(&lo->lo_ctl_mutex); lo->lo_refcnt++; mutex_unlock(&lo->lo_ctl_mutex); - mutex_unlock(&loop_mutex); return 0; } @@ -1515,7 +1512,6 @@ static int lo_release(struct gendisk *disk, fmode_t mode) struct loop_device *lo = disk->private_data; int err; - mutex_lock(&loop_mutex); mutex_lock(&lo->lo_ctl_mutex); if (--lo->lo_refcnt) @@ -1540,7 +1536,6 @@ static int lo_release(struct gendisk *disk, fmode_t mode) out: mutex_unlock(&lo->lo_ctl_mutex); out_unlocked: - mutex_unlock(&loop_mutex); return 0; } diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c index 9045c52abd25..fb2bb35c62cb 100644 --- a/drivers/scsi/scsi_lib.c +++ b/drivers/scsi/scsi_lib.c @@ -443,7 +443,7 @@ static void scsi_run_queue(struct request_queue *q) &sdev->request_queue->queue_flags); if (flagset) queue_flag_set(QUEUE_FLAG_REENTER, sdev->request_queue); - __blk_run_queue(sdev->request_queue); + __blk_run_queue(sdev->request_queue, false); if (flagset) queue_flag_clear(QUEUE_FLAG_REENTER, sdev->request_queue); spin_unlock(sdev->request_queue->queue_lock); diff --git a/drivers/scsi/scsi_transport_fc.c b/drivers/scsi/scsi_transport_fc.c index 998c01be3234..5c3ccfc6b622 100644 --- a/drivers/scsi/scsi_transport_fc.c +++ b/drivers/scsi/scsi_transport_fc.c @@ -3829,7 +3829,7 @@ fc_bsg_goose_queue(struct fc_rport *rport) !test_bit(QUEUE_FLAG_REENTER, &rport->rqst_q->queue_flags); if (flagset) queue_flag_set(QUEUE_FLAG_REENTER, rport->rqst_q); - __blk_run_queue(rport->rqst_q); + __blk_run_queue(rport->rqst_q, false); if (flagset) queue_flag_clear(QUEUE_FLAG_REENTER, rport->rqst_q); spin_unlock_irqrestore(rport->rqst_q->queue_lock, flags); diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 4d18ff34670a..d5063e1b5555 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -699,7 +699,7 @@ extern void blk_start_queue(struct request_queue *q); extern void blk_stop_queue(struct request_queue *q); extern void blk_sync_queue(struct request_queue *q); extern void __blk_stop_queue(struct request_queue *q); -extern void __blk_run_queue(struct request_queue *); +extern void __blk_run_queue(struct request_queue *q, bool force_kblockd); extern void blk_run_queue(struct request_queue *); extern int blk_rq_map_user(struct request_queue *, struct request *, struct rq_map_data *, void __user *, unsigned long, @@ -1088,7 +1088,6 @@ static inline void put_dev_sector(Sector p) struct work_struct; int kblockd_schedule_work(struct request_queue *q, struct work_struct *work); -int kblockd_schedule_delayed_work(struct request_queue *q, struct delayed_work *dwork, unsigned long delay); #ifdef CONFIG_BLK_CGROUP /* @@ -1136,7 +1135,6 @@ static inline uint64_t rq_io_start_time_ns(struct request *req) extern int blk_throtl_init(struct request_queue *q); extern void blk_throtl_exit(struct request_queue *q); extern int blk_throtl_bio(struct request_queue *q, struct bio **bio); -extern void throtl_schedule_delayed_work(struct request_queue *q, unsigned long delay); extern void throtl_shutdown_timer_wq(struct request_queue *q); #else /* CONFIG_BLK_DEV_THROTTLING */ static inline int blk_throtl_bio(struct request_queue *q, struct bio **bio) @@ -1146,7 +1144,6 @@ static inline int blk_throtl_bio(struct request_queue *q, struct bio **bio) static inline int blk_throtl_init(struct request_queue *q) { return 0; } static inline int blk_throtl_exit(struct request_queue *q) { return 0; } -static inline void throtl_schedule_delayed_work(struct request_queue *q, unsigned long delay) {} static inline void throtl_shutdown_timer_wq(struct request_queue *q) {} #endif /* CONFIG_BLK_DEV_THROTTLING */ diff --git a/include/linux/blktrace_api.h b/include/linux/blktrace_api.h index 3395cf7130f5..b22fb0d3db0f 100644 --- a/include/linux/blktrace_api.h +++ b/include/linux/blktrace_api.h @@ -245,7 +245,6 @@ static inline int blk_cmd_buf_len(struct request *rq) extern void blk_dump_cmd(char *buf, struct request *rq); extern void blk_fill_rwbs(char *rwbs, u32 rw, int bytes); -extern void blk_fill_rwbs_rq(char *rwbs, struct request *rq); #endif /* CONFIG_EVENT_TRACING && CONFIG_BLOCK */ diff --git a/include/trace/events/block.h b/include/trace/events/block.h index aba421d68f6f..78f18adb49c8 100644 --- a/include/trace/events/block.h +++ b/include/trace/events/block.h @@ -31,7 +31,7 @@ DECLARE_EVENT_CLASS(block_rq_with_error, 0 : blk_rq_sectors(rq); __entry->errors = rq->errors; - blk_fill_rwbs_rq(__entry->rwbs, rq); + blk_fill_rwbs(__entry->rwbs, rq->cmd_flags, blk_rq_bytes(rq)); blk_dump_cmd(__get_str(cmd), rq); ), @@ -118,7 +118,7 @@ DECLARE_EVENT_CLASS(block_rq, __entry->bytes = (rq->cmd_type == REQ_TYPE_BLOCK_PC) ? blk_rq_bytes(rq) : 0; - blk_fill_rwbs_rq(__entry->rwbs, rq); + blk_fill_rwbs(__entry->rwbs, rq->cmd_flags, blk_rq_bytes(rq)); blk_dump_cmd(__get_str(cmd), rq); memcpy(__entry->comm, current->comm, TASK_COMM_LEN); ), @@ -563,7 +563,7 @@ TRACE_EVENT(block_rq_remap, __entry->nr_sector = blk_rq_sectors(rq); __entry->old_dev = dev; __entry->old_sector = from; - blk_fill_rwbs_rq(__entry->rwbs, rq); + blk_fill_rwbs(__entry->rwbs, rq->cmd_flags, blk_rq_bytes(rq)); ), TP_printk("%d,%d %s %llu + %u <- (%d,%d) %llu", diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c index d95721f33702..cbafed7d4f38 100644 --- a/kernel/trace/blktrace.c +++ b/kernel/trace/blktrace.c @@ -1827,21 +1827,5 @@ void blk_fill_rwbs(char *rwbs, u32 rw, int bytes) rwbs[i] = '\0'; } -void blk_fill_rwbs_rq(char *rwbs, struct request *rq) -{ - int rw = rq->cmd_flags & 0x03; - int bytes; - - if (rq->cmd_flags & REQ_DISCARD) - rw |= REQ_DISCARD; - - if (rq->cmd_flags & REQ_SECURE) - rw |= REQ_SECURE; - - bytes = blk_rq_bytes(rq); - - blk_fill_rwbs(rwbs, rw, bytes); -} - #endif /* CONFIG_EVENT_TRACING */