From d705ae6b133f9f6a8beee617b1224b6a5c99c5da Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Wed, 15 Feb 2012 09:45:49 +0100 Subject: block: replace icq->changed with icq->flags icq->changed was used for ICQ_*_CHANGED bits. Rename it to flags and access it under ioc->lock instead of using atomic bitops. ioc_get_changed() is added so that the changed part can be fetched and cleared as before. icq->flags will be used to carry other flags. Signed-off-by: Tejun Heo Tested-by: Shaohua Li Signed-off-by: Jens Axboe --- block/blk-ioc.c | 30 ++++++++++++++++++++++++++---- block/cfq-iosched.c | 12 ++++++------ 2 files changed, 32 insertions(+), 10 deletions(-) (limited to 'block') diff --git a/block/blk-ioc.c b/block/blk-ioc.c index 8b782a63c29..811879c752e 100644 --- a/block/blk-ioc.c +++ b/block/blk-ioc.c @@ -363,13 +363,13 @@ struct io_cq *ioc_create_icq(struct request_queue *q, gfp_t gfp_mask) return icq; } -void ioc_set_changed(struct io_context *ioc, int which) +void ioc_set_icq_flags(struct io_context *ioc, unsigned int flags) { struct io_cq *icq; struct hlist_node *n; hlist_for_each_entry(icq, n, &ioc->icq_list, ioc_node) - set_bit(which, &icq->changed); + icq->flags |= flags; } /** @@ -387,7 +387,7 @@ void ioc_ioprio_changed(struct io_context *ioc, int ioprio) spin_lock_irqsave(&ioc->lock, flags); ioc->ioprio = ioprio; - ioc_set_changed(ioc, ICQ_IOPRIO_CHANGED); + ioc_set_icq_flags(ioc, ICQ_IOPRIO_CHANGED); spin_unlock_irqrestore(&ioc->lock, flags); } @@ -404,11 +404,33 @@ void ioc_cgroup_changed(struct io_context *ioc) unsigned long flags; spin_lock_irqsave(&ioc->lock, flags); - ioc_set_changed(ioc, ICQ_CGROUP_CHANGED); + ioc_set_icq_flags(ioc, ICQ_CGROUP_CHANGED); spin_unlock_irqrestore(&ioc->lock, flags); } EXPORT_SYMBOL(ioc_cgroup_changed); +/** + * icq_get_changed - fetch and clear icq changed mask + * @icq: icq of interest + * + * Fetch and clear ICQ_*_CHANGED bits from @icq. Grabs and releases + * @icq->ioc->lock. + */ +unsigned icq_get_changed(struct io_cq *icq) +{ + unsigned int changed = 0; + unsigned long flags; + + if (unlikely(icq->flags & ICQ_CHANGED_MASK)) { + spin_lock_irqsave(&icq->ioc->lock, flags); + changed = icq->flags & ICQ_CHANGED_MASK; + icq->flags &= ~ICQ_CHANGED_MASK; + spin_unlock_irqrestore(&icq->ioc->lock, flags); + } + return changed; +} +EXPORT_SYMBOL(icq_get_changed); + static int __init blk_ioc_init(void) { iocontext_cachep = kmem_cache_create("blkdev_ioc", diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c index d0ba5053366..45729525356 100644 --- a/block/cfq-iosched.c +++ b/block/cfq-iosched.c @@ -3470,20 +3470,20 @@ cfq_set_request(struct request_queue *q, struct request *rq, gfp_t gfp_mask) const int rw = rq_data_dir(rq); const bool is_sync = rq_is_sync(rq); struct cfq_queue *cfqq; + unsigned int changed; might_sleep_if(gfp_mask & __GFP_WAIT); spin_lock_irq(q->queue_lock); /* handle changed notifications */ - if (unlikely(cic->icq.changed)) { - if (test_and_clear_bit(ICQ_IOPRIO_CHANGED, &cic->icq.changed)) - changed_ioprio(cic); + changed = icq_get_changed(&cic->icq); + if (unlikely(changed & ICQ_IOPRIO_CHANGED)) + changed_ioprio(cic); #ifdef CONFIG_CFQ_GROUP_IOSCHED - if (test_and_clear_bit(ICQ_CGROUP_CHANGED, &cic->icq.changed)) - changed_cgroup(cic); + if (unlikely(changed & ICQ_CGROUP_CHANGED)) + changed_cgroup(cic); #endif - } new_queue: cfqq = cic_to_cfqq(cic, is_sync); -- cgit v1.2.3