diff options
| -rw-r--r-- | block/blk-core.c | 39 | ||||
| -rw-r--r-- | block/blk-merge.c | 6 | ||||
| -rw-r--r-- | block/blk-settings.c | 2 | ||||
| -rw-r--r-- | block/blk-tag.c | 8 | ||||
| -rw-r--r-- | block/elevator.c | 13 | ||||
| -rw-r--r-- | drivers/block/loop.c | 2 | ||||
| -rw-r--r-- | drivers/block/ub.c | 2 | ||||
| -rw-r--r-- | drivers/md/dm-table.c | 7 | ||||
| -rw-r--r-- | drivers/md/md.c | 3 | ||||
| -rw-r--r-- | drivers/scsi/scsi_debug.c | 2 | ||||
| -rw-r--r-- | drivers/scsi/scsi_lib.c | 31 | ||||
| -rw-r--r-- | drivers/scsi/scsi_transport_sas.c | 3 | ||||
| -rw-r--r-- | include/linux/blkdev.h | 33 |
13 files changed, 102 insertions, 49 deletions
diff --git a/block/blk-core.c b/block/blk-core.c index e447799..d2f23ec 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -198,7 +198,8 @@ void blk_plug_device(struct request_queue *q) if (blk_queue_stopped(q)) return; - if (!test_and_set_bit(QUEUE_FLAG_PLUGGED, &q->queue_flags)) { + if (!test_bit(QUEUE_FLAG_PLUGGED, &q->queue_flags)) { + __set_bit(QUEUE_FLAG_PLUGGED, &q->queue_flags); mod_timer(&q->unplug_timer, jiffies + q->unplug_delay); blk_add_trace_generic(q, NULL, 0, BLK_TA_PLUG); } @@ -213,9 +214,10 @@ int blk_remove_plug(struct request_queue *q) { WARN_ON(!irqs_disabled()); - if (!test_and_clear_bit(QUEUE_FLAG_PLUGGED, &q->queue_flags)) + if (!test_bit(QUEUE_FLAG_PLUGGED, &q->queue_flags)) return 0; + queue_flag_clear(QUEUE_FLAG_PLUGGED, q); del_timer(&q->unplug_timer); return 1; } @@ -311,15 +313,16 @@ void blk_start_queue(struct request_queue *q) { WARN_ON(!irqs_disabled()); - clear_bit(QUEUE_FLAG_STOPPED, &q->queue_flags); + queue_flag_clear(QUEUE_FLAG_STOPPED, q); /* * one level of recursion is ok and is much faster than kicking * the unplug handling */ - if (!test_and_set_bit(QUEUE_FLAG_REENTER, &q->queue_flags)) { + if (!test_bit(QUEUE_FLAG_REENTER, &q->queue_flags)) { + queue_flag_set(QUEUE_FLAG_REENTER, q); q->request_fn(q); - clear_bit(QUEUE_FLAG_REENTER, &q->queue_flags); + queue_flag_clear(QUEUE_FLAG_REENTER, q); } else { blk_plug_device(q); kblockd_schedule_work(&q->unplug_work); @@ -344,7 +347,7 @@ EXPORT_SYMBOL(blk_start_queue); void blk_stop_queue(struct request_queue *q) { blk_remove_plug(q); - set_bit(QUEUE_FLAG_STOPPED, &q->queue_flags); + queue_flag_set(QUEUE_FLAG_STOPPED, q); } EXPORT_SYMBOL(blk_stop_queue); @@ -373,11 +376,8 @@ EXPORT_SYMBOL(blk_sync_queue); * blk_run_queue - run a single device queue * @q: The queue to run */ -void blk_run_queue(struct request_queue *q) +void __blk_run_queue(struct request_queue *q) { - unsigned long flags; - - spin_lock_irqsave(q->queue_lock, flags); blk_remove_plug(q); /* @@ -385,15 +385,28 @@ void blk_run_queue(struct request_queue *q) * handling reinvoke the handler shortly if we already got there. */ if (!elv_queue_empty(q)) { - if (!test_and_set_bit(QUEUE_FLAG_REENTER, &q->queue_flags)) { + if (!test_bit(QUEUE_FLAG_REENTER, &q->queue_flags)) { + queue_flag_set(QUEUE_FLAG_REENTER, q); q->request_fn(q); - clear_bit(QUEUE_FLAG_REENTER, &q->queue_flags); + queue_flag_clear(QUEUE_FLAG_REENTER, q); } else { blk_plug_device(q); kblockd_schedule_work(&q->unplug_work); } } +} +EXPORT_SYMBOL(__blk_run_queue); +/** + * blk_run_queue - run a single device queue + * @q: The queue to run + */ +void blk_run_queue(struct request_queue *q) +{ + unsigned long flags; + + spin_lock_irqsave(q->queue_lock, flags); + __blk_run_queue(q); spin_unlock_irqrestore(q->queue_lock, flags); } EXPORT_SYMBOL(blk_run_queue); @@ -406,7 +419,7 @@ void blk_put_queue(struct request_queue *q) void blk_cleanup_queue(struct request_queue *q) { mutex_lock(&q->sysfs_lock); - set_bit(QUEUE_FLAG_DEAD, &q->queue_flags); + queue_flag_set_unlocked(QUEUE_FLAG_DEAD, q); mutex_unlock(&q->sysfs_lock); if (q->elevator) diff --git a/block/blk-merge.c b/block/blk-merge.c index b5c5c4a..73b2356 100644 --- a/block/blk-merge.c +++ b/block/blk-merge.c @@ -55,7 +55,7 @@ void blk_recalc_rq_segments(struct request *rq) if (!rq->bio) return; - cluster = q->queue_flags & (1 << QUEUE_FLAG_CLUSTER); + cluster = test_bit(QUEUE_FLAG_CLUSTER, &q->queue_flags); hw_seg_size = seg_size = 0; phys_size = hw_size = nr_phys_segs = nr_hw_segs = 0; rq_for_each_segment(bv, rq, iter) { @@ -128,7 +128,7 @@ EXPORT_SYMBOL(blk_recount_segments); static int blk_phys_contig_segment(struct request_queue *q, struct bio *bio, struct bio *nxt) { - if (!(q->queue_flags & (1 << QUEUE_FLAG_CLUSTER))) + if (!test_bit(QUEUE_FLAG_CLUSTER, &q->queue_flags)) return 0; if (!BIOVEC_PHYS_MERGEABLE(__BVEC_END(bio), __BVEC_START(nxt))) @@ -175,7 +175,7 @@ int blk_rq_map_sg(struct request_queue *q, struct request *rq, int nsegs, cluster; nsegs = 0; - cluster = q->queue_flags & (1 << QUEUE_FLAG_CLUSTER); + cluster = test_bit(QUEUE_FLAG_CLUSTER, &q->queue_flags); /* * for each bio in rq diff --git a/block/blk-settings.c b/block/blk-settings.c index 77b51dc..6089384 100644 --- a/block/blk-settings.c +++ b/block/blk-settings.c @@ -287,7 +287,7 @@ void blk_queue_stack_limits(struct request_queue *t, struct request_queue *b) t->max_segment_size = min(t->max_segment_size, b->max_segment_size); t->hardsect_size = max(t->hardsect_size, b->hardsect_size); if (!test_bit(QUEUE_FLAG_CLUSTER, &b->queue_flags)) - clear_bit(QUEUE_FLAG_CLUSTER, &t->queue_flags); + queue_flag_clear(QUEUE_FLAG_CLUSTER, t); } EXPORT_SYMBOL(blk_queue_stack_limits); diff --git a/block/blk-tag.c b/block/blk-tag.c index 4780a46..e176ddb 100644 --- a/block/blk-tag.c +++ b/block/blk-tag.c @@ -70,7 +70,7 @@ void __blk_queue_free_tags(struct request_queue *q) __blk_free_tags(bqt); q->queue_tags = NULL; - q->queue_flags &= ~(1 << QUEUE_FLAG_QUEUED); + queue_flag_clear(QUEUE_FLAG_QUEUED, q); } /** @@ -98,7 +98,7 @@ EXPORT_SYMBOL(blk_free_tags); **/ void blk_queue_free_tags(struct request_queue *q) { - clear_bit(QUEUE_FLAG_QUEUED, &q->queue_flags); + queue_flag_clear(QUEUE_FLAG_QUEUED, q); } EXPORT_SYMBOL(blk_queue_free_tags); @@ -188,7 +188,7 @@ int blk_queue_init_tags(struct request_queue *q, int depth, rc = blk_queue_resize_tags(q, depth); if (rc) return rc; - set_bit(QUEUE_FLAG_QUEUED, &q->queue_flags); + queue_flag_set(QUEUE_FLAG_QUEUED, q); return 0; } else atomic_inc(&tags->refcnt); @@ -197,7 +197,7 @@ int blk_queue_init_tags(struct request_queue *q, int depth, * assign it, all done */ q->queue_tags = tags; - q->queue_flags |= (1 << QUEUE_FLAG_QUEUED); + queue_flag_set(QUEUE_FLAG_QUEUED, q); INIT_LIST_HEAD(&q->tag_busy_list); return 0; fail: diff --git a/block/elevator.c b/block/elevator.c index 88318c3..e8a90fe 100644 --- a/block/elevator.c +++ b/block/elevator.c @@ -1070,7 +1070,7 @@ static int elevator_switch(struct request_queue *q, struct elevator_type *new_e) */ spin_lock_irq(q->queue_lock); - set_bit(QUEUE_FLAG_ELVSWITCH, &q->queue_flags); + queue_flag_set(QUEUE_FLAG_ELVSWITCH, q); elv_drain_elevator(q); @@ -1104,7 +1104,10 @@ static int elevator_switch(struct request_queue *q, struct elevator_type *new_e) * finally exit old elevator and turn off BYPASS. */ elevator_exit(old_elevator); - clear_bit(QUEUE_FLAG_ELVSWITCH, &q->queue_flags); + spin_lock_irq(q->queue_lock); + queue_flag_clear(QUEUE_FLAG_ELVSWITCH, q); + spin_unlock_irq(q->queue_lock); + return 1; fail_register: @@ -1115,7 +1118,11 @@ fail_register: elevator_exit(e); q->elevator = old_elevator; elv_register_queue(q); - clear_bit(QUEUE_FLAG_ELVSWITCH, &q->queue_flags); + + spin_lock_irq(q->queue_lock); + queue_flag_clear(QUEUE_FLAG_ELVSWITCH, q); + spin_unlock_irq(q->queue_lock); + return 0; } diff --git a/drivers/block/loop.c b/drivers/block/loop.c index f7f1635..d3a25b0 100644 --- a/drivers/block/loop.c +++ b/drivers/block/loop.c @@ -546,7 +546,7 @@ static void loop_unplug(struct request_queue *q) { struct loop_device *lo = q->queuedata; - clear_bit(QUEUE_FLAG_PLUGGED, &q->queue_flags); + queue_flag_clear_unlocked(QUEUE_FLAG_PLUGGED, q); blk_run_address_space(lo->lo_backing_file->f_mapping); } diff --git a/drivers/block/ub.c b/drivers/block/ub.c index 27bfe72..e322cce 100644 --- a/drivers/block/ub.c +++ b/drivers/block/ub.c @@ -2399,7 +2399,7 @@ static void ub_disconnect(struct usb_interface *intf) del_gendisk(lun->disk); /* * I wish I could do: - * set_bit(QUEUE_FLAG_DEAD, &q->queue_flags); + * queue_flag_set(QUEUE_FLAG_DEAD, q); * As it is, we rely on our internal poisoning and let * the upper levels to spin furiously failing all the I/O. */ diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c index 51be533..73326e7 100644 --- a/drivers/md/dm-table.c +++ b/drivers/md/dm-table.c @@ -873,10 +873,13 @@ void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q) q->max_hw_sectors = t->limits.max_hw_sectors; q->seg_boundary_mask = t->limits.seg_boundary_mask; q->bounce_pfn = t->limits.bounce_pfn; + /* XXX: the below will probably go bug. must ensure there can be no + * concurrency on queue_flags, and use the unlocked versions... + */ if (t->limits.no_cluster) - q->queue_flags &= ~(1 << QUEUE_FLAG_CLUSTER); + queue_flag_clear(QUEUE_FLAG_CLUSTER, q); else - q->queue_flags |= (1 << QUEUE_FLAG_CLUSTER); + queue_flag_set(QUEUE_FLAG_CLUSTER, q); } diff --git a/drivers/md/md.c b/drivers/md/md.c index 87620b7..acd716b 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -282,7 +282,8 @@ static mddev_t * mddev_find(dev_t unit) kfree(new); return NULL; } - set_bit(QUEUE_FLAG_CLUSTER, &new->queue->queue_flags); + /* Can be unlocked because the queue is new: no concurrency */ + queue_flag_set_unlocked(QUEUE_FLAG_CLUSTER, new->queue); blk_queue_make_request(new->queue, md_fail_request); diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c index 07103c3..f6600bf 100644 --- a/drivers/scsi/scsi_debug.c +++ b/drivers/scsi/scsi_debug.c @@ -1773,7 +1773,7 @@ static int scsi_debug_slave_alloc(struct scsi_device *sdp) if (SCSI_DEBUG_OPT_NOISE & scsi_debug_opts) printk(KERN_INFO "scsi_debug: slave_alloc <%u %u %u %u>\n", sdp->host->host_no, sdp->channel, sdp->id, sdp->lun); - set_bit(QUEUE_FLAG_BIDI, &sdp->request_queue->queue_flags); + queue_flag_set_unlocked(QUEUE_FLAG_BIDI, sdp->request_queue); return 0; } diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c index 67f412b..d545ad1 100644 --- a/drivers/scsi/scsi_lib.c +++ b/drivers/scsi/scsi_lib.c @@ -536,6 +536,9 @@ static void scsi_run_queue(struct request_queue *q) !shost->host_blocked && !shost->host_self_blocked && !((shost->can_queue > 0) && (shost->host_busy >= shost->can_queue))) { + + int flagset; + /* * As long as shost is accepting commands and we have * starved queues, call blk_run_queue. scsi_request_fn @@ -549,19 +552,20 @@ static void scsi_run_queue(struct request_queue *q) sdev = list_entry(shost->starved_list.next, struct scsi_device, starved_entry); list_del_init(&sdev->starved_entry); - spin_unlock_irqrestore(shost->host_lock, flags); - + spin_unlock(shost->host_lock); + + spin_lock(sdev->request_queue->queue_lock); + flagset = test_bit(QUEUE_FLAG_REENTER, &q->queue_flags) && + !test_bit(QUEUE_FLAG_REENTER, + &sdev->request_queue->queue_flags); + if (flagset) + queue_flag_set(QUEUE_FLAG_REENTER, sdev->request_queue); + __blk_run_queue(sdev->request_queue); + if (flagset) + queue_flag_clear(QUEUE_FLAG_REENTER, sdev->request_queue); + spin_unlock(sdev->request_queue->queue_lock); - if (test_bit(QUEUE_FLAG_REENTER, &q->queue_flags) && - !test_and_set_bit(QUEUE_FLAG_REENTER, - &sdev->request_queue->queue_flags)) { - blk_run_queue(sdev->request_queue); - clear_bit(QUEUE_FLAG_REENTER, - &sdev->request_queue->queue_flags); - } else - blk_run_queue(sdev->request_queue); - - spin_lock_irqsave(shost->host_lock, flags); + spin_lock(shost->host_lock); if (unlikely(!list_empty(&sdev->starved_entry))) /* * sdev lost a race, and was put back on the @@ -1585,8 +1589,9 @@ struct request_queue *__scsi_alloc_queue(struct Scsi_Host *shost, blk_queue_max_segment_size(q, dma_get_max_seg_size(dev)); + /* New queue, no concurrency on queue_flags */ if (!shost->use_clustering) - clear_bit(QUEUE_FLAG_CLUSTER, &q->queue_flags); + queue_flag_clear_unlocked(QUEUE_FLAG_CLUSTER, q); /* * set a reasonable default alignment on word boundaries: the diff --git a/drivers/scsi/scsi_transport_sas.c b/drivers/scsi/scsi_transport_sas.c index 7899e3d..f4461d3 100644 --- a/drivers/scsi/scsi_transport_sas.c +++ b/drivers/scsi/scsi_transport_sas.c @@ -248,8 +248,7 @@ static int sas_bsg_initialize(struct Scsi_Host *shost, struct sas_rphy *rphy) else q->queuedata = shost; - set_bit(QUEUE_FLAG_BIDI, &q->queue_flags); - + queue_flag_set_unlocked(QUEUE_FLAG_BIDI, q); return 0; } diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index c5065e3..8ca481c 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -408,6 +408,30 @@ struct request_queue #define QUEUE_FLAG_ELVSWITCH 8 /* don't use elevator, just do FIFO */ #define QUEUE_FLAG_BIDI 9 /* queue supports bidi requests */ +static inline void queue_flag_set_unlocked(unsigned int flag, + struct request_queue *q) +{ + __set_bit(flag, &q->queue_flags); +} + +static inline void queue_flag_set(unsigned int flag, struct request_queue *q) +{ + WARN_ON_ONCE(!spin_is_locked(q->queue_lock)); + __set_bit(flag, &q->queue_flags); +} + +static inline void queue_flag_clear_unlocked(unsigned int flag, + struct request_queue *q) +{ + __clear_bit(flag, &q->queue_flags); +} + +static inline void queue_flag_clear(unsigned int flag, struct request_queue *q) +{ + WARN_ON_ONCE(!spin_is_locked(q->queue_lock)); + __clear_bit(flag, &q->queue_flags); +} + enum { /* * Hardbarrier is supported with one of the following methods. @@ -496,17 +520,17 @@ static inline int blk_queue_full(struct request_queue *q, int rw) static inline void blk_set_queue_full(struct request_queue *q, int rw) { if (rw == READ) - set_bit(QUEUE_FLAG_READFULL, &q->queue_flags); + queue_flag_set(QUEUE_FLAG_READFULL, q); else - set_bit(QUEUE_FLAG_WRITEFULL, &q->queue_flags); + queue_flag_set(QUEUE_FLAG_WRITEFULL, q); } static inline void blk_clear_queue_full(struct request_queue *q, int rw) { if (rw == READ) - clear_bit(QUEUE_FLAG_READFULL, &q->queue_flags); + queue_flag_clear(QUEUE_FLAG_READFULL, q); else - clear_bit(QUEUE_FLAG_WRITEFULL, &q->queue_flags); + queue_flag_clear(QUEUE_FLAG_WRITEFULL, q); } @@ -626,6 +650,7 @@ 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 *); extern void blk_start_queueing(struct request_queue *); extern int blk_rq_map_user(struct request_queue *, struct request *, void __user *, unsigned long); |
