From 3793c65c13e4751c7a10f98198bae1758453eb0e Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Tue, 30 May 2006 21:11:04 +0200 Subject: [PATCH] [PATCH] cfq-iosched: fixup locking and ->queue_list list management - Drop cic from the list when seen as dead. - Fixup the locking, just use a simple spinlock. Signed-off-by: Jens Axboe Signed-off-by: Linus Torvalds --- block/cfq-iosched.c | 25 +++++++++++++------------ 1 file changed, 13 insertions(+), 12 deletions(-) diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c index 2540dfaa3e38..11ce6aaf1bd0 100644 --- a/block/cfq-iosched.c +++ b/block/cfq-iosched.c @@ -33,7 +33,7 @@ static int cfq_slice_idle = HZ / 70; #define CFQ_KEY_ASYNC (0) -static DEFINE_RWLOCK(cfq_exit_lock); +static DEFINE_SPINLOCK(cfq_exit_lock); /* * for the hash of cfqq inside the cfqd @@ -1284,7 +1284,7 @@ static void cfq_exit_io_context(struct io_context *ioc) /* * put the reference this task is holding to the various queues */ - read_lock_irqsave(&cfq_exit_lock, flags); + spin_lock_irqsave(&cfq_exit_lock, flags); n = rb_first(&ioc->cic_root); while (n != NULL) { @@ -1294,7 +1294,7 @@ static void cfq_exit_io_context(struct io_context *ioc) n = rb_next(n); } - read_unlock_irqrestore(&cfq_exit_lock, flags); + spin_unlock_irqrestore(&cfq_exit_lock, flags); } static struct cfq_io_context * @@ -1400,17 +1400,17 @@ static int cfq_ioc_set_ioprio(struct io_context *ioc, unsigned int ioprio) struct cfq_io_context *cic; struct rb_node *n; - write_lock(&cfq_exit_lock); + spin_lock(&cfq_exit_lock); n = rb_first(&ioc->cic_root); while (n != NULL) { cic = rb_entry(n, struct cfq_io_context, rb_node); - + changed_ioprio(cic); n = rb_next(n); } - write_unlock(&cfq_exit_lock); + spin_unlock(&cfq_exit_lock); return 0; } @@ -1475,9 +1475,10 @@ out: static void cfq_drop_dead_cic(struct io_context *ioc, struct cfq_io_context *cic) { - read_lock(&cfq_exit_lock); + spin_lock(&cfq_exit_lock); rb_erase(&cic->rb_node, &ioc->cic_root); - read_unlock(&cfq_exit_lock); + list_del_init(&cic->queue_list); + spin_unlock(&cfq_exit_lock); kmem_cache_free(cfq_ioc_pool, cic); atomic_dec(&ioc_count); } @@ -1545,11 +1546,11 @@ restart: BUG(); } - read_lock(&cfq_exit_lock); + spin_lock(&cfq_exit_lock); rb_link_node(&cic->rb_node, parent, p); rb_insert_color(&cic->rb_node, &ioc->cic_root); list_add(&cic->queue_list, &cfqd->cic_list); - read_unlock(&cfq_exit_lock); + spin_unlock(&cfq_exit_lock); } /* @@ -2187,7 +2188,7 @@ static void cfq_exit_queue(elevator_t *e) cfq_shutdown_timer_wq(cfqd); - write_lock(&cfq_exit_lock); + spin_lock(&cfq_exit_lock); spin_lock_irq(q->queue_lock); if (cfqd->active_queue) @@ -2210,7 +2211,7 @@ static void cfq_exit_queue(elevator_t *e) } spin_unlock_irq(q->queue_lock); - write_unlock(&cfq_exit_lock); + spin_unlock(&cfq_exit_lock); cfq_shutdown_timer_wq(cfqd); -- 2.30.2