diff options
Diffstat (limited to 'block')
| -rw-r--r-- | block/cfq-iosched.c | 205 | ||||
| -rw-r--r-- | block/ll_rw_blk.c | 19 |
2 files changed, 108 insertions, 116 deletions
diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c index bde40a6ae665..bb43a1677626 100644 --- a/block/cfq-iosched.c +++ b/block/cfq-iosched.c @@ -1190,19 +1190,19 @@ cfq_find_cfq_hash(struct cfq_data *cfqd, unsigned int key, unsigned short prio) return __cfq_find_cfq_hash(cfqd, key, prio, hash_long(key, CFQ_QHASH_SHIFT)); } -static void cfq_free_io_context(struct cfq_io_context *cic) +static void cfq_free_io_context(struct io_context *ioc) { struct cfq_io_context *__cic; - struct list_head *entry, *next; - int freed = 1; + struct rb_node *n; + int freed = 0; - list_for_each_safe(entry, next, &cic->list) { - __cic = list_entry(entry, struct cfq_io_context, list); + while ((n = rb_first(&ioc->cic_root)) != NULL) { + __cic = rb_entry(n, struct cfq_io_context, rb_node); + rb_erase(&__cic->rb_node, &ioc->cic_root); kmem_cache_free(cfq_ioc_pool, __cic); freed++; } - kmem_cache_free(cfq_ioc_pool, cic); if (atomic_sub_and_test(freed, &ioc_count) && ioc_gone) complete(ioc_gone); } @@ -1210,8 +1210,7 @@ static void cfq_free_io_context(struct cfq_io_context *cic) static void cfq_trim(struct io_context *ioc) { ioc->set_ioprio = NULL; - if (ioc->cic) - cfq_free_io_context(ioc->cic); + cfq_free_io_context(ioc); } /* @@ -1250,26 +1249,26 @@ static void cfq_exit_single_io_context(struct cfq_io_context *cic) spin_unlock(q->queue_lock); } -static void cfq_exit_io_context(struct cfq_io_context *cic) +static void cfq_exit_io_context(struct io_context *ioc) { struct cfq_io_context *__cic; - struct list_head *entry; unsigned long flags; - - local_irq_save(flags); + struct rb_node *n; /* * put the reference this task is holding to the various queues */ - read_lock(&cfq_exit_lock); - list_for_each(entry, &cic->list) { - __cic = list_entry(entry, struct cfq_io_context, list); + read_lock_irqsave(&cfq_exit_lock, flags); + + n = rb_first(&ioc->cic_root); + while (n != NULL) { + __cic = rb_entry(n, struct cfq_io_context, rb_node); + cfq_exit_single_io_context(__cic); + n = rb_next(n); } - cfq_exit_single_io_context(cic); - read_unlock(&cfq_exit_lock); - local_irq_restore(flags); + read_unlock_irqrestore(&cfq_exit_lock, flags); } static struct cfq_io_context * @@ -1278,10 +1277,10 @@ cfq_alloc_io_context(struct cfq_data *cfqd, gfp_t gfp_mask) struct cfq_io_context *cic = kmem_cache_alloc(cfq_ioc_pool, gfp_mask); if (cic) { - INIT_LIST_HEAD(&cic->list); + RB_CLEAR(&cic->rb_node); + cic->key = NULL; cic->cfqq[ASYNC] = NULL; cic->cfqq[SYNC] = NULL; - cic->key = NULL; cic->last_end_request = jiffies; cic->ttime_total = 0; cic->ttime_samples = 0; @@ -1373,15 +1372,17 @@ static inline void changed_ioprio(struct cfq_io_context *cic) 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); - cic = ioc->cic; - - changed_ioprio(cic); - - list_for_each_entry(cic, &cic->list, list) + 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); @@ -1445,14 +1446,67 @@ out: return cfqq; } +static struct cfq_io_context * +cfq_cic_rb_lookup(struct cfq_data *cfqd, struct io_context *ioc) +{ + struct rb_node *n = ioc->cic_root.rb_node; + struct cfq_io_context *cic; + void *key = cfqd; + + while (n) { + cic = rb_entry(n, struct cfq_io_context, rb_node); + + if (key < cic->key) + n = n->rb_left; + else if (key > cic->key) + n = n->rb_right; + else + return cic; + } + + return NULL; +} + +static inline void +cfq_cic_link(struct cfq_data *cfqd, struct io_context *ioc, + struct cfq_io_context *cic) +{ + struct rb_node **p = &ioc->cic_root.rb_node; + struct rb_node *parent = NULL; + struct cfq_io_context *__cic; + + read_lock(&cfq_exit_lock); + + cic->ioc = ioc; + cic->key = cfqd; + + ioc->set_ioprio = cfq_ioc_set_ioprio; + + while (*p) { + parent = *p; + __cic = rb_entry(parent, struct cfq_io_context, rb_node); + + if (cic->key < __cic->key) + p = &(*p)->rb_left; + else if (cic->key > __cic->key) + p = &(*p)->rb_right; + else + BUG(); + } + + 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); +} + /* * Setup general io context and cfq io context. There can be several cfq * io contexts per general io context, if this process is doing io to more - * than one device managed by cfq. Note that caller is holding a reference to - * cfqq, so we don't need to worry about it disappearing + * than one device managed by cfq. */ static struct cfq_io_context * -cfq_get_io_context(struct cfq_data *cfqd, pid_t pid, gfp_t gfp_mask) +cfq_get_io_context(struct cfq_data *cfqd, gfp_t gfp_mask) { struct io_context *ioc = NULL; struct cfq_io_context *cic; @@ -1463,88 +1517,15 @@ cfq_get_io_context(struct cfq_data *cfqd, pid_t pid, gfp_t gfp_mask) if (!ioc) return NULL; -restart: - if ((cic = ioc->cic) == NULL) { - cic = cfq_alloc_io_context(cfqd, gfp_mask); - - if (cic == NULL) - goto err; - - /* - * manually increment generic io_context usage count, it - * cannot go away since we are already holding one ref to it - */ - cic->ioc = ioc; - cic->key = cfqd; - read_lock(&cfq_exit_lock); - ioc->set_ioprio = cfq_ioc_set_ioprio; - ioc->cic = cic; - list_add(&cic->queue_list, &cfqd->cic_list); - read_unlock(&cfq_exit_lock); - } else { - struct cfq_io_context *__cic; - - /* - * the first cic on the list is actually the head itself - */ - if (cic->key == cfqd) - goto out; - - if (unlikely(!cic->key)) { - read_lock(&cfq_exit_lock); - if (list_empty(&cic->list)) - ioc->cic = NULL; - else - ioc->cic = list_entry(cic->list.next, - struct cfq_io_context, - list); - read_unlock(&cfq_exit_lock); - kmem_cache_free(cfq_ioc_pool, cic); - atomic_dec(&ioc_count); - goto restart; - } - - /* - * cic exists, check if we already are there. linear search - * should be ok here, the list will usually not be more than - * 1 or a few entries long - */ - list_for_each_entry(__cic, &cic->list, list) { - /* - * this process is already holding a reference to - * this queue, so no need to get one more - */ - if (__cic->key == cfqd) { - cic = __cic; - goto out; - } - if (unlikely(!__cic->key)) { - read_lock(&cfq_exit_lock); - list_del(&__cic->list); - read_unlock(&cfq_exit_lock); - kmem_cache_free(cfq_ioc_pool, __cic); - atomic_dec(&ioc_count); - goto restart; - } - } + cic = cfq_cic_rb_lookup(cfqd, ioc); + if (cic) + goto out; - /* - * nope, process doesn't have a cic assoicated with this - * cfqq yet. get a new one and add to list - */ - __cic = cfq_alloc_io_context(cfqd, gfp_mask); - if (__cic == NULL) - goto err; - - __cic->ioc = ioc; - __cic->key = cfqd; - read_lock(&cfq_exit_lock); - list_add(&__cic->list, &cic->list); - list_add(&__cic->queue_list, &cfqd->cic_list); - read_unlock(&cfq_exit_lock); - cic = __cic; - } + cic = cfq_alloc_io_context(cfqd, gfp_mask); + if (cic == NULL) + goto err; + cfq_cic_link(cfqd, ioc, cic); out: return cic; err: @@ -1965,7 +1946,7 @@ cfq_set_request(request_queue_t *q, struct request *rq, struct bio *bio, might_sleep_if(gfp_mask & __GFP_WAIT); - cic = cfq_get_io_context(cfqd, key, gfp_mask); + cic = cfq_get_io_context(cfqd, gfp_mask); spin_lock_irqsave(q->queue_lock, flags); @@ -2133,11 +2114,14 @@ static void cfq_exit_queue(elevator_t *e) request_queue_t *q = cfqd->queue; cfq_shutdown_timer_wq(cfqd); + write_lock(&cfq_exit_lock); spin_lock_irq(q->queue_lock); + if (cfqd->active_queue) __cfq_slice_expired(cfqd, cfqd->active_queue, 0); - while(!list_empty(&cfqd->cic_list)) { + + while (!list_empty(&cfqd->cic_list)) { struct cfq_io_context *cic = list_entry(cfqd->cic_list.next, struct cfq_io_context, queue_list); @@ -2152,6 +2136,7 @@ static void cfq_exit_queue(elevator_t *e) cic->key = NULL; list_del_init(&cic->queue_list); } + spin_unlock_irq(q->queue_lock); write_unlock(&cfq_exit_lock); diff --git a/block/ll_rw_blk.c b/block/ll_rw_blk.c index 82469db25100..cb608768ca37 100644 --- a/block/ll_rw_blk.c +++ b/block/ll_rw_blk.c @@ -3539,11 +3539,15 @@ void put_io_context(struct io_context *ioc) BUG_ON(atomic_read(&ioc->refcount) == 0); if (atomic_dec_and_test(&ioc->refcount)) { + struct cfq_io_context *cic; + rcu_read_lock(); if (ioc->aic && ioc->aic->dtor) ioc->aic->dtor(ioc->aic); - if (ioc->cic && ioc->cic->dtor) - ioc->cic->dtor(ioc->cic); + if (ioc->cic_root.rb_node != NULL) { + cic = rb_entry(rb_first(&ioc->cic_root), struct cfq_io_context, rb_node); + cic->dtor(ioc); + } rcu_read_unlock(); kmem_cache_free(iocontext_cachep, ioc); @@ -3556,6 +3560,7 @@ void exit_io_context(void) { unsigned long flags; struct io_context *ioc; + struct cfq_io_context *cic; local_irq_save(flags); task_lock(current); @@ -3567,9 +3572,11 @@ void exit_io_context(void) if (ioc->aic && ioc->aic->exit) ioc->aic->exit(ioc->aic); - if (ioc->cic && ioc->cic->exit) - ioc->cic->exit(ioc->cic); - + if (ioc->cic_root.rb_node != NULL) { + cic = rb_entry(rb_first(&ioc->cic_root), struct cfq_io_context, rb_node); + cic->exit(ioc); + } + put_io_context(ioc); } @@ -3598,7 +3605,7 @@ struct io_context *current_io_context(gfp_t gfp_flags) ret->last_waited = jiffies; /* doesn't matter... */ ret->nr_batch_requests = 0; /* because this is 0 */ ret->aic = NULL; - ret->cic = NULL; + ret->cic_root.rb_node = NULL; tsk->io_context = ret; } |