From 283287a52e3c3f7f8f9da747f4b8c5202740d776 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Wed, 14 Dec 2011 00:33:38 +0100 Subject: block, cfq: misc updates to cfq_io_context Make the following changes to prepare for ioc/cic management cleanup. * Add cic->q so that ioc can determine the associated queue without querying cfq. This will eventually replace ->key. * Factor out cfq_release_cic() from cic_free_func(). This function assumes that the caller handled locking. * Rename __cfq_exit_single_io_context() to cfq_exit_cic() and make it take only @cic. * Restructure cfq_cic_link() for future updates. This patch doesn't introduce any functional changes. Signed-off-by: Tejun Heo Signed-off-by: Jens Axboe --- block/cfq-iosched.c | 58 +++++++++++++++++++++++++++++------------------------ 1 file changed, 32 insertions(+), 26 deletions(-) (limited to 'block') diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c index d42d89ccce1..a612ca65f37 100644 --- a/block/cfq-iosched.c +++ b/block/cfq-iosched.c @@ -2709,21 +2709,26 @@ static void cfq_cic_free(struct cfq_io_context *cic) call_rcu(&cic->rcu_head, cfq_cic_free_rcu); } -static void cic_free_func(struct io_context *ioc, struct cfq_io_context *cic) +static void cfq_release_cic(struct cfq_io_context *cic) { - unsigned long flags; + struct io_context *ioc = cic->ioc; unsigned long dead_key = (unsigned long) cic->key; BUG_ON(!(dead_key & CIC_DEAD_KEY)); - - spin_lock_irqsave(&ioc->lock, flags); radix_tree_delete(&ioc->radix_root, dead_key >> CIC_DEAD_INDEX_SHIFT); hlist_del_rcu(&cic->cic_list); - spin_unlock_irqrestore(&ioc->lock, flags); - cfq_cic_free(cic); } +static void cic_free_func(struct io_context *ioc, struct cfq_io_context *cic) +{ + unsigned long flags; + + spin_lock_irqsave(&ioc->lock, flags); + cfq_release_cic(cic); + spin_unlock_irqrestore(&ioc->lock, flags); +} + /* * Must be called with rcu_read_lock() held or preemption otherwise disabled. * Only two callers of this - ->dtor() which is called with the rcu_read_lock(), @@ -2773,9 +2778,9 @@ static void cfq_exit_cfqq(struct cfq_data *cfqd, struct cfq_queue *cfqq) cfq_put_queue(cfqq); } -static void __cfq_exit_single_io_context(struct cfq_data *cfqd, - struct cfq_io_context *cic) +static void cfq_exit_cic(struct cfq_io_context *cic) { + struct cfq_data *cfqd = cic_to_cfqd(cic); struct io_context *ioc = cic->ioc; list_del_init(&cic->queue_list); @@ -2823,7 +2828,7 @@ static void cfq_exit_single_io_context(struct io_context *ioc, */ smp_read_barrier_depends(); if (cic->key == cfqd) - __cfq_exit_single_io_context(cfqd, cic); + cfq_exit_cic(cic); spin_unlock_irqrestore(q->queue_lock, flags); } @@ -3161,28 +3166,29 @@ static int cfq_cic_link(struct cfq_data *cfqd, struct io_context *ioc, int ret; ret = radix_tree_preload(gfp_mask); - if (!ret) { - cic->ioc = ioc; - cic->key = cfqd; + if (ret) + goto out; - spin_lock_irqsave(&ioc->lock, flags); - ret = radix_tree_insert(&ioc->radix_root, cfqd->queue->id, cic); - if (!ret) - hlist_add_head_rcu(&cic->cic_list, &ioc->cic_list); - spin_unlock_irqrestore(&ioc->lock, flags); + cic->ioc = ioc; + cic->key = cfqd; + cic->q = cfqd->queue; + + spin_lock_irqsave(&ioc->lock, flags); + ret = radix_tree_insert(&ioc->radix_root, cfqd->queue->id, cic); + if (!ret) + hlist_add_head_rcu(&cic->cic_list, &ioc->cic_list); + spin_unlock_irqrestore(&ioc->lock, flags); - radix_tree_preload_end(); + radix_tree_preload_end(); - if (!ret) { - spin_lock_irqsave(cfqd->queue->queue_lock, flags); - list_add(&cic->queue_list, &cfqd->cic_list); - spin_unlock_irqrestore(cfqd->queue->queue_lock, flags); - } + if (!ret) { + spin_lock_irqsave(cfqd->queue->queue_lock, flags); + list_add(&cic->queue_list, &cfqd->cic_list); + spin_unlock_irqrestore(cfqd->queue->queue_lock, flags); } - +out: if (ret) printk(KERN_ERR "cfq: cic link failed!\n"); - return ret; } @@ -3922,7 +3928,7 @@ static void cfq_exit_queue(struct elevator_queue *e) struct cfq_io_context, queue_list); - __cfq_exit_single_io_context(cfqd, cic); + cfq_exit_cic(cic); } cfq_put_async_queues(cfqd); -- cgit v1.2.3-70-g09d2