| From: Sebastian Andrzej Siewior <bigeasy@linutronix.de> |
| Date: Fri, 13 Feb 2015 11:01:26 +0100 |
| Subject: block: blk-mq: Use swait |
| |
| | BUG: sleeping function called from invalid context at kernel/locking/rtmutex.c:914 |
| | in_atomic(): 1, irqs_disabled(): 0, pid: 255, name: kworker/u257:6 |
| | 5 locks held by kworker/u257:6/255: |
| | #0: ("events_unbound"){.+.+.+}, at: [<ffffffff8108edf1>] process_one_work+0x171/0x5e0 |
| | #1: ((&entry->work)){+.+.+.}, at: [<ffffffff8108edf1>] process_one_work+0x171/0x5e0 |
| | #2: (&shost->scan_mutex){+.+.+.}, at: [<ffffffffa000faa3>] __scsi_add_device+0xa3/0x130 [scsi_mod] |
| | #3: (&set->tag_list_lock){+.+...}, at: [<ffffffff812f09fa>] blk_mq_init_queue+0x96a/0xa50 |
| | #4: (rcu_read_lock_sched){......}, at: [<ffffffff8132887d>] percpu_ref_kill_and_confirm+0x1d/0x120 |
| | Preemption disabled at:[<ffffffff812eff76>] blk_mq_freeze_queue_start+0x56/0x70 |
| | |
| | CPU: 2 PID: 255 Comm: kworker/u257:6 Not tainted 3.18.7-rt0+ #1 |
| | Workqueue: events_unbound async_run_entry_fn |
| | 0000000000000003 ffff8800bc29f998 ffffffff815b3a12 0000000000000000 |
| | 0000000000000000 ffff8800bc29f9b8 ffffffff8109aa16 ffff8800bc29fa28 |
| | ffff8800bc5d1bc8 ffff8800bc29f9e8 ffffffff815b8dd4 ffff880000000000 |
| | Call Trace: |
| | [<ffffffff815b3a12>] dump_stack+0x4f/0x7c |
| | [<ffffffff8109aa16>] __might_sleep+0x116/0x190 |
| | [<ffffffff815b8dd4>] rt_spin_lock+0x24/0x60 |
| | [<ffffffff810b6089>] __wake_up+0x29/0x60 |
| | [<ffffffff812ee06e>] blk_mq_usage_counter_release+0x1e/0x20 |
| | [<ffffffff81328966>] percpu_ref_kill_and_confirm+0x106/0x120 |
| | [<ffffffff812eff76>] blk_mq_freeze_queue_start+0x56/0x70 |
| | [<ffffffff812f0000>] blk_mq_update_tag_set_depth+0x40/0xd0 |
| | [<ffffffff812f0a1c>] blk_mq_init_queue+0x98c/0xa50 |
| | [<ffffffffa000dcf0>] scsi_mq_alloc_queue+0x20/0x60 [scsi_mod] |
| | [<ffffffffa000ea35>] scsi_alloc_sdev+0x2f5/0x370 [scsi_mod] |
| | [<ffffffffa000f494>] scsi_probe_and_add_lun+0x9e4/0xdd0 [scsi_mod] |
| | [<ffffffffa000fb26>] __scsi_add_device+0x126/0x130 [scsi_mod] |
| | [<ffffffffa013033f>] ata_scsi_scan_host+0xaf/0x200 [libata] |
| | [<ffffffffa012b5b6>] async_port_probe+0x46/0x60 [libata] |
| | [<ffffffff810978fb>] async_run_entry_fn+0x3b/0xf0 |
| | [<ffffffff8108ee81>] process_one_work+0x201/0x5e0 |
| |
| Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> |
| --- |
| block/blk-core.c | 6 +++--- |
| block/blk-mq.c | 6 +++--- |
| include/linux/blkdev.h | 2 +- |
| 3 files changed, 7 insertions(+), 7 deletions(-) |
| |
| --- a/block/blk-core.c |
| +++ b/block/blk-core.c |
| @@ -660,7 +660,7 @@ int blk_queue_enter(struct request_queue |
| if (nowait) |
| return -EBUSY; |
| |
| - ret = wait_event_interruptible(q->mq_freeze_wq, |
| + ret = swait_event_interruptible(q->mq_freeze_wq, |
| !atomic_read(&q->mq_freeze_depth) || |
| blk_queue_dying(q)); |
| if (blk_queue_dying(q)) |
| @@ -680,7 +680,7 @@ static void blk_queue_usage_counter_rele |
| struct request_queue *q = |
| container_of(ref, struct request_queue, q_usage_counter); |
| |
| - wake_up_all(&q->mq_freeze_wq); |
| + swake_up_all(&q->mq_freeze_wq); |
| } |
| |
| static void blk_rq_timed_out_timer(unsigned long data) |
| @@ -749,7 +749,7 @@ struct request_queue *blk_alloc_queue_no |
| q->bypass_depth = 1; |
| __set_bit(QUEUE_FLAG_BYPASS, &q->queue_flags); |
| |
| - init_waitqueue_head(&q->mq_freeze_wq); |
| + init_swait_queue_head(&q->mq_freeze_wq); |
| |
| /* |
| * Init percpu_ref in atomic mode so that it's faster to shutdown. |
| --- a/block/blk-mq.c |
| +++ b/block/blk-mq.c |
| @@ -92,7 +92,7 @@ EXPORT_SYMBOL_GPL(blk_mq_freeze_queue_st |
| |
| static void blk_mq_freeze_queue_wait(struct request_queue *q) |
| { |
| - wait_event(q->mq_freeze_wq, percpu_ref_is_zero(&q->q_usage_counter)); |
| + swait_event(q->mq_freeze_wq, percpu_ref_is_zero(&q->q_usage_counter)); |
| } |
| |
| /* |
| @@ -130,7 +130,7 @@ void blk_mq_unfreeze_queue(struct reques |
| WARN_ON_ONCE(freeze_depth < 0); |
| if (!freeze_depth) { |
| percpu_ref_reinit(&q->q_usage_counter); |
| - wake_up_all(&q->mq_freeze_wq); |
| + swake_up_all(&q->mq_freeze_wq); |
| } |
| } |
| EXPORT_SYMBOL_GPL(blk_mq_unfreeze_queue); |
| @@ -149,7 +149,7 @@ void blk_mq_wake_waiters(struct request_ |
| * dying, we need to ensure that processes currently waiting on |
| * the queue are notified as well. |
| */ |
| - wake_up_all(&q->mq_freeze_wq); |
| + swake_up_all(&q->mq_freeze_wq); |
| } |
| |
| bool blk_mq_can_queue(struct blk_mq_hw_ctx *hctx) |
| --- a/include/linux/blkdev.h |
| +++ b/include/linux/blkdev.h |
| @@ -458,7 +458,7 @@ struct request_queue { |
| struct throtl_data *td; |
| #endif |
| struct rcu_head rcu_head; |
| - wait_queue_head_t mq_freeze_wq; |
| + struct swait_queue_head mq_freeze_wq; |
| struct percpu_ref q_usage_counter; |
| struct list_head all_q_node; |
| |