From c58698073218f2c8f2fc5982fa3938c2d3803b9f Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Wed, 14 Dec 2011 00:33:41 +0100 Subject: [PATCH] block, cfq: reorganize cfq_io_context into generic and cfq specific parts Currently io_context and cfq logics are mixed without clear boundary. Most of io_context is independent from cfq but cfq_io_context handling logic is dispersed between generic ioc code and cfq. cfq_io_context represents association between an io_context and a request_queue, which is a concept useful outside of cfq, but it also contains fields which are useful only to cfq. This patch takes out generic part and put it into io_cq (io context-queue) and the rest into cfq_io_cq (cic moniker remains the same) which contains io_cq. The following changes are made together. * cfq_ttime and cfq_io_cq now live in cfq-iosched.c. * All related fields, functions and constants are renamed accordingly. * ioc->ioc_data is now "struct io_cq *" instead of "void *" and renamed to icq_hint. This prepares for io_context API cleanup. Documentation is currently sparse. It will be added later. Changes in this patch are mechanical and don't cause functional change. Signed-off-by: Tejun Heo Signed-off-by: Jens Axboe --- block/blk-ioc.c | 58 +++++---- block/cfq-iosched.c | 248 ++++++++++++++++++++------------------ include/linux/iocontext.h | 43 +++---- 3 files changed, 175 insertions(+), 174 deletions(-) diff --git a/block/blk-ioc.c b/block/blk-ioc.c index e23c797b4685..dc5e69d335a0 100644 --- a/block/blk-ioc.c +++ b/block/blk-ioc.c @@ -46,7 +46,7 @@ EXPORT_SYMBOL(get_io_context); /* * Slow path for ioc release in put_io_context(). Performs double-lock - * dancing to unlink all cic's and then frees ioc. + * dancing to unlink all icq's and then frees ioc. */ static void ioc_release_fn(struct work_struct *work) { @@ -56,11 +56,10 @@ static void ioc_release_fn(struct work_struct *work) spin_lock_irq(&ioc->lock); - while (!hlist_empty(&ioc->cic_list)) { - struct cfq_io_context *cic = hlist_entry(ioc->cic_list.first, - struct cfq_io_context, - cic_list); - struct request_queue *this_q = cic->q; + while (!hlist_empty(&ioc->icq_list)) { + struct io_cq *icq = hlist_entry(ioc->icq_list.first, + struct io_cq, ioc_node); + struct request_queue *this_q = icq->q; if (this_q != last_q) { /* @@ -89,8 +88,8 @@ static void ioc_release_fn(struct work_struct *work) continue; } ioc_release_depth_inc(this_q); - cic->exit(cic); - cic->release(cic); + icq->exit(icq); + icq->release(icq); ioc_release_depth_dec(this_q); } @@ -131,10 +130,10 @@ void put_io_context(struct io_context *ioc, struct request_queue *locked_q) return; /* - * Destroy @ioc. This is a bit messy because cic's are chained + * Destroy @ioc. This is a bit messy because icq's are chained * from both ioc and queue, and ioc->lock nests inside queue_lock. - * The inner ioc->lock should be held to walk our cic_list and then - * for each cic the outer matching queue_lock should be grabbed. + * The inner ioc->lock should be held to walk our icq_list and then + * for each icq the outer matching queue_lock should be grabbed. * ie. We need to do reverse-order double lock dancing. * * Another twist is that we are often called with one of the @@ -153,11 +152,10 @@ void put_io_context(struct io_context *ioc, struct request_queue *locked_q) spin_lock_irqsave_nested(&ioc->lock, flags, ioc_release_depth(locked_q)); - while (!hlist_empty(&ioc->cic_list)) { - struct cfq_io_context *cic = hlist_entry(ioc->cic_list.first, - struct cfq_io_context, - cic_list); - struct request_queue *this_q = cic->q; + while (!hlist_empty(&ioc->icq_list)) { + struct io_cq *icq = hlist_entry(ioc->icq_list.first, + struct io_cq, ioc_node); + struct request_queue *this_q = icq->q; if (this_q != last_q) { if (last_q && last_q != locked_q) @@ -170,8 +168,8 @@ void put_io_context(struct io_context *ioc, struct request_queue *locked_q) continue; } ioc_release_depth_inc(this_q); - cic->exit(cic); - cic->release(cic); + icq->exit(icq); + icq->release(icq); ioc_release_depth_dec(this_q); } @@ -180,8 +178,8 @@ void put_io_context(struct io_context *ioc, struct request_queue *locked_q) spin_unlock_irqrestore(&ioc->lock, flags); - /* if no cic's left, we're done; otherwise, kick release_work */ - if (hlist_empty(&ioc->cic_list)) + /* if no icq is left, we're done; otherwise, kick release_work */ + if (hlist_empty(&ioc->icq_list)) kmem_cache_free(iocontext_cachep, ioc); else schedule_work(&ioc->release_work); @@ -219,8 +217,8 @@ void create_io_context_slowpath(struct task_struct *task, gfp_t gfp_flags, atomic_long_set(&ioc->refcount, 1); atomic_set(&ioc->nr_tasks, 1); spin_lock_init(&ioc->lock); - INIT_RADIX_TREE(&ioc->radix_root, GFP_ATOMIC | __GFP_HIGH); - INIT_HLIST_HEAD(&ioc->cic_list); + INIT_RADIX_TREE(&ioc->icq_tree, GFP_ATOMIC | __GFP_HIGH); + INIT_HLIST_HEAD(&ioc->icq_list); INIT_WORK(&ioc->release_work, ioc_release_fn); /* try to install, somebody might already have beaten us to it */ @@ -270,11 +268,11 @@ EXPORT_SYMBOL(get_task_io_context); void ioc_set_changed(struct io_context *ioc, int which) { - struct cfq_io_context *cic; + struct io_cq *icq; struct hlist_node *n; - hlist_for_each_entry(cic, n, &ioc->cic_list, cic_list) - set_bit(which, &cic->changed); + hlist_for_each_entry(icq, n, &ioc->icq_list, ioc_node) + set_bit(which, &icq->changed); } /** @@ -282,8 +280,8 @@ void ioc_set_changed(struct io_context *ioc, int which) * @ioc: io_context of interest * @ioprio: new ioprio * - * @ioc's ioprio has changed to @ioprio. Set %CIC_IOPRIO_CHANGED for all - * cic's. iosched is responsible for checking the bit and applying it on + * @ioc's ioprio has changed to @ioprio. Set %ICQ_IOPRIO_CHANGED for all + * icq's. iosched is responsible for checking the bit and applying it on * request issue path. */ void ioc_ioprio_changed(struct io_context *ioc, int ioprio) @@ -292,7 +290,7 @@ void ioc_ioprio_changed(struct io_context *ioc, int ioprio) spin_lock_irqsave(&ioc->lock, flags); ioc->ioprio = ioprio; - ioc_set_changed(ioc, CIC_IOPRIO_CHANGED); + ioc_set_changed(ioc, ICQ_IOPRIO_CHANGED); spin_unlock_irqrestore(&ioc->lock, flags); } @@ -300,7 +298,7 @@ void ioc_ioprio_changed(struct io_context *ioc, int ioprio) * ioc_cgroup_changed - notify cgroup change * @ioc: io_context of interest * - * @ioc's cgroup has changed. Set %CIC_CGROUP_CHANGED for all cic's. + * @ioc's cgroup has changed. Set %ICQ_CGROUP_CHANGED for all icq's. * iosched is responsible for checking the bit and applying it on request * issue path. */ @@ -309,7 +307,7 @@ void ioc_cgroup_changed(struct io_context *ioc) unsigned long flags; spin_lock_irqsave(&ioc->lock, flags); - ioc_set_changed(ioc, CIC_CGROUP_CHANGED); + ioc_set_changed(ioc, ICQ_CGROUP_CHANGED); spin_unlock_irqrestore(&ioc->lock, flags); } diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c index 5f7e4d161404..d2f16fcdec7f 100644 --- a/block/cfq-iosched.c +++ b/block/cfq-iosched.c @@ -54,13 +54,12 @@ static const int cfq_hist_divisor = 4; #define CFQQ_SECT_THR_NONROT (sector_t)(2 * 32) #define CFQQ_SEEKY(cfqq) (hweight32(cfqq->seek_history) > 32/8) -#define RQ_CIC(rq) \ - ((struct cfq_io_context *) (rq)->elevator_private[0]) +#define RQ_CIC(rq) icq_to_cic((rq)->elevator_private[0]) #define RQ_CFQQ(rq) (struct cfq_queue *) ((rq)->elevator_private[1]) #define RQ_CFQG(rq) (struct cfq_group *) ((rq)->elevator_private[2]) static struct kmem_cache *cfq_pool; -static struct kmem_cache *cfq_ioc_pool; +static struct kmem_cache *cfq_icq_pool; #define CFQ_PRIO_LISTS IOPRIO_BE_NR #define cfq_class_idle(cfqq) ((cfqq)->ioprio_class == IOPRIO_CLASS_IDLE) @@ -69,6 +68,14 @@ static struct kmem_cache *cfq_ioc_pool; #define sample_valid(samples) ((samples) > 80) #define rb_entry_cfqg(node) rb_entry((node), struct cfq_group, rb_node) +struct cfq_ttime { + unsigned long last_end_request; + + unsigned long ttime_total; + unsigned long ttime_samples; + unsigned long ttime_mean; +}; + /* * Most of our rbtree usage is for sorting with min extraction, so * if we cache the leftmost node we don't have to walk down the tree @@ -210,6 +217,12 @@ struct cfq_group { struct cfq_ttime ttime; }; +struct cfq_io_cq { + struct io_cq icq; /* must be the first member */ + struct cfq_queue *cfqq[2]; + struct cfq_ttime ttime; +}; + /* * Per block device queue structure */ @@ -261,7 +274,7 @@ struct cfq_data { struct work_struct unplug_work; struct cfq_queue *active_queue; - struct cfq_io_context *active_cic; + struct cfq_io_cq *active_cic; /* * async queue for each priority case @@ -284,7 +297,7 @@ struct cfq_data { unsigned int cfq_group_idle; unsigned int cfq_latency; - struct list_head cic_list; + struct list_head icq_list; /* * Fallback dummy cfqq for extreme OOM conditions @@ -457,24 +470,28 @@ static inline int cfqg_busy_async_queues(struct cfq_data *cfqd, static void cfq_dispatch_insert(struct request_queue *, struct request *); static struct cfq_queue *cfq_get_queue(struct cfq_data *, bool, struct io_context *, gfp_t); -static struct cfq_io_context *cfq_cic_lookup(struct cfq_data *, - struct io_context *); +static struct cfq_io_cq *cfq_cic_lookup(struct cfq_data *, struct io_context *); -static inline struct cfq_queue *cic_to_cfqq(struct cfq_io_context *cic, - bool is_sync) +static inline struct cfq_io_cq *icq_to_cic(struct io_cq *icq) +{ + /* cic->icq is the first member, %NULL will convert to %NULL */ + return container_of(icq, struct cfq_io_cq, icq); +} + +static inline struct cfq_queue *cic_to_cfqq(struct cfq_io_cq *cic, bool is_sync) { return cic->cfqq[is_sync]; } -static inline void cic_set_cfqq(struct cfq_io_context *cic, - struct cfq_queue *cfqq, bool is_sync) +static inline void cic_set_cfqq(struct cfq_io_cq *cic, struct cfq_queue *cfqq, + bool is_sync) { cic->cfqq[is_sync] = cfqq; } -static inline struct cfq_data *cic_to_cfqd(struct cfq_io_context *cic) +static inline struct cfq_data *cic_to_cfqd(struct cfq_io_cq *cic) { - return cic->q->elevator->elevator_data; + return cic->icq.q->elevator->elevator_data; } /* @@ -1541,7 +1558,7 @@ static struct request * cfq_find_rq_fmerge(struct cfq_data *cfqd, struct bio *bio) { struct task_struct *tsk = current; - struct cfq_io_context *cic; + struct cfq_io_cq *cic; struct cfq_queue *cfqq; cic = cfq_cic_lookup(cfqd, tsk->io_context); @@ -1655,7 +1672,7 @@ static int cfq_allow_merge(struct request_queue *q, struct request *rq, struct bio *bio) { struct cfq_data *cfqd = q->elevator->elevator_data; - struct cfq_io_context *cic; + struct cfq_io_cq *cic; struct cfq_queue *cfqq; /* @@ -1671,7 +1688,7 @@ static int cfq_allow_merge(struct request_queue *q, struct request *rq, * and %current are guaranteed to be equal. Avoid lookup which * requires queue_lock by using @rq's cic. */ - if (current->io_context == RQ_CIC(rq)->ioc) { + if (current->io_context == RQ_CIC(rq)->icq.ioc) { cic = RQ_CIC(rq); } else { cic = cfq_cic_lookup(cfqd, current->io_context); @@ -1761,7 +1778,7 @@ __cfq_slice_expired(struct cfq_data *cfqd, struct cfq_queue *cfqq, cfqd->active_queue = NULL; if (cfqd->active_cic) { - put_io_context(cfqd->active_cic->ioc, cfqd->queue); + put_io_context(cfqd->active_cic->icq.ioc, cfqd->queue); cfqd->active_cic = NULL; } } @@ -1981,7 +1998,7 @@ static bool cfq_should_idle(struct cfq_data *cfqd, struct cfq_queue *cfqq) static void cfq_arm_slice_timer(struct cfq_data *cfqd) { struct cfq_queue *cfqq = cfqd->active_queue; - struct cfq_io_context *cic; + struct cfq_io_cq *cic; unsigned long sl, group_idle = 0; /* @@ -2016,7 +2033,7 @@ static void cfq_arm_slice_timer(struct cfq_data *cfqd) * task has exited, don't wait */ cic = cfqd->active_cic; - if (!cic || !atomic_read(&cic->ioc->nr_tasks)) + if (!cic || !atomic_read(&cic->icq.ioc->nr_tasks)) return; /* @@ -2567,9 +2584,9 @@ static bool cfq_dispatch_request(struct cfq_data *cfqd, struct cfq_queue *cfqq) cfq_dispatch_insert(cfqd->queue, rq); if (!cfqd->active_cic) { - struct cfq_io_context *cic = RQ_CIC(rq); + struct cfq_io_cq *cic = RQ_CIC(rq); - atomic_long_inc(&cic->ioc->refcount); + atomic_long_inc(&cic->icq.ioc->refcount); cfqd->active_cic = cic; } @@ -2652,24 +2669,24 @@ static void cfq_put_queue(struct cfq_queue *cfqq) cfq_put_cfqg(cfqg); } -static void cfq_cic_free_rcu(struct rcu_head *head) +static void cfq_icq_free_rcu(struct rcu_head *head) { - kmem_cache_free(cfq_ioc_pool, - container_of(head, struct cfq_io_context, rcu_head)); + kmem_cache_free(cfq_icq_pool, + icq_to_cic(container_of(head, struct io_cq, rcu_head))); } -static void cfq_cic_free(struct cfq_io_context *cic) +static void cfq_icq_free(struct io_cq *icq) { - call_rcu(&cic->rcu_head, cfq_cic_free_rcu); + call_rcu(&icq->rcu_head, cfq_icq_free_rcu); } -static void cfq_release_cic(struct cfq_io_context *cic) +static void cfq_release_icq(struct io_cq *icq) { - struct io_context *ioc = cic->ioc; + struct io_context *ioc = icq->ioc; - radix_tree_delete(&ioc->radix_root, cic->q->id); - hlist_del(&cic->cic_list); - cfq_cic_free(cic); + radix_tree_delete(&ioc->icq_tree, icq->q->id); + hlist_del(&icq->ioc_node); + cfq_icq_free(icq); } static void cfq_put_cooperator(struct cfq_queue *cfqq) @@ -2705,20 +2722,21 @@ static void cfq_exit_cfqq(struct cfq_data *cfqd, struct cfq_queue *cfqq) cfq_put_queue(cfqq); } -static void cfq_exit_cic(struct cfq_io_context *cic) +static void cfq_exit_icq(struct io_cq *icq) { + struct cfq_io_cq *cic = icq_to_cic(icq); struct cfq_data *cfqd = cic_to_cfqd(cic); - struct io_context *ioc = cic->ioc; + struct io_context *ioc = icq->ioc; - list_del_init(&cic->queue_list); + list_del_init(&icq->q_node); /* - * Both setting lookup hint to and clearing it from @cic are done - * under queue_lock. If it's not pointing to @cic now, it never + * Both setting lookup hint to and clearing it from @icq are done + * under queue_lock. If it's not pointing to @icq now, it never * will. Hint assignment itself can race safely. */ - if (rcu_dereference_raw(ioc->ioc_data) == cic) - rcu_assign_pointer(ioc->ioc_data, NULL); + if (rcu_dereference_raw(ioc->icq_hint) == icq) + rcu_assign_pointer(ioc->icq_hint, NULL); if (cic->cfqq[BLK_RW_ASYNC]) { cfq_exit_cfqq(cfqd, cic->cfqq[BLK_RW_ASYNC]); @@ -2731,19 +2749,18 @@ static void cfq_exit_cic(struct cfq_io_context *cic) } } -static struct cfq_io_context * -cfq_alloc_io_context(struct cfq_data *cfqd, gfp_t gfp_mask) +static struct cfq_io_cq *cfq_alloc_cic(struct cfq_data *cfqd, gfp_t gfp_mask) { - struct cfq_io_context *cic; + struct cfq_io_cq *cic; - cic = kmem_cache_alloc_node(cfq_ioc_pool, gfp_mask | __GFP_ZERO, + cic = kmem_cache_alloc_node(cfq_icq_pool, gfp_mask | __GFP_ZERO, cfqd->queue->node); if (cic) { cic->ttime.last_end_request = jiffies; - INIT_LIST_HEAD(&cic->queue_list); - INIT_HLIST_NODE(&cic->cic_list); - cic->exit = cfq_exit_cic; - cic->release = cfq_release_cic; + INIT_LIST_HEAD(&cic->icq.q_node); + INIT_HLIST_NODE(&cic->icq.ioc_node); + cic->icq.exit = cfq_exit_icq; + cic->icq.release = cfq_release_icq; } return cic; @@ -2791,7 +2808,7 @@ static void cfq_init_prio_data(struct cfq_queue *cfqq, struct io_context *ioc) cfq_clear_cfqq_prio_changed(cfqq); } -static void changed_ioprio(struct cfq_io_context *cic) +static void changed_ioprio(struct cfq_io_cq *cic) { struct cfq_data *cfqd = cic_to_cfqd(cic); struct cfq_queue *cfqq; @@ -2802,7 +2819,7 @@ static void changed_ioprio(struct cfq_io_context *cic) cfqq = cic->cfqq[BLK_RW_ASYNC]; if (cfqq) { struct cfq_queue *new_cfqq; - new_cfqq = cfq_get_queue(cfqd, BLK_RW_ASYNC, cic->ioc, + new_cfqq = cfq_get_queue(cfqd, BLK_RW_ASYNC, cic->icq.ioc, GFP_ATOMIC); if (new_cfqq) { cic->cfqq[BLK_RW_ASYNC] = new_cfqq; @@ -2836,7 +2853,7 @@ static void cfq_init_cfqq(struct cfq_data *cfqd, struct cfq_queue *cfqq, } #ifdef CONFIG_CFQ_GROUP_IOSCHED -static void changed_cgroup(struct cfq_io_context *cic) +static void changed_cgroup(struct cfq_io_cq *cic) { struct cfq_queue *sync_cfqq = cic_to_cfqq(cic, 1); struct cfq_data *cfqd = cic_to_cfqd(cic); @@ -2864,7 +2881,7 @@ cfq_find_alloc_queue(struct cfq_data *cfqd, bool is_sync, struct io_context *ioc, gfp_t gfp_mask) { struct cfq_queue *cfqq, *new_cfqq = NULL; - struct cfq_io_context *cic; + struct cfq_io_cq *cic; struct cfq_group *cfqg; retry: @@ -2956,56 +2973,57 @@ cfq_get_queue(struct cfq_data *cfqd, bool is_sync, struct io_context *ioc, } /** - * cfq_cic_lookup - lookup cfq_io_context + * cfq_cic_lookup - lookup cfq_io_cq * @cfqd: the associated cfq_data * @ioc: the associated io_context * - * Look up cfq_io_context associated with @cfqd - @ioc pair. Must be - * called with queue_lock held. + * Look up cfq_io_cq associated with @cfqd - @ioc pair. Must be called + * with queue_lock held. */ -static struct cfq_io_context * +static struct cfq_io_cq * cfq_cic_lookup(struct cfq_data *cfqd, struct io_context *ioc) { struct request_queue *q = cfqd->queue; - struct cfq_io_context *cic; + struct io_cq *icq; lockdep_assert_held(cfqd->queue->queue_lock); if (unlikely(!ioc)) return NULL; /* - * cic's are indexed from @ioc using radix tree and hint pointer, + * icq's are indexed from @ioc using radix tree and hint pointer, * both of which are protected with RCU. All removals are done * holding both q and ioc locks, and we're holding q lock - if we - * find a cic which points to us, it's guaranteed to be valid. + * find a icq which points to us, it's guaranteed to be valid. */ rcu_read_lock(); - cic = rcu_dereference(ioc->ioc_data); - if (cic && cic->q == q) + icq = rcu_dereference(ioc->icq_hint); + if (icq && icq->q == q) goto out; - cic = radix_tree_lookup(&ioc->radix_root, cfqd->queue->id); - if (cic && cic->q == q) - rcu_assign_pointer(ioc->ioc_data, cic); /* allowed to race */ + icq = radix_tree_lookup(&ioc->icq_tree, cfqd->queue->id); + if (icq && icq->q == q) + rcu_assign_pointer(ioc->icq_hint, icq); /* allowed to race */ else - cic = NULL; + icq = NULL; out: rcu_read_unlock(); - return cic; + return icq_to_cic(icq); } /** - * cfq_create_cic - create and link a cfq_io_context + * cfq_create_cic - create and link a cfq_io_cq * @cfqd: cfqd of interest * @gfp_mask: allocation mask * - * Make sure cfq_io_context linking %current->io_context and @cfqd exists. - * If ioc and/or cic doesn't exist, they will be created using @gfp_mask. + * Make sure cfq_io_cq linking %current->io_context and @cfqd exists. If + * ioc and/or cic doesn't exist, they will be created using @gfp_mask. */ static int cfq_create_cic(struct cfq_data *cfqd, gfp_t gfp_mask) { struct request_queue *q = cfqd->queue; - struct cfq_io_context *cic = NULL; + struct io_cq *icq = NULL; + struct cfq_io_cq *cic; struct io_context *ioc; int ret = -ENOMEM; @@ -3016,26 +3034,27 @@ static int cfq_create_cic(struct cfq_data *cfqd, gfp_t gfp_mask) if (!ioc) goto out; - cic = cfq_alloc_io_context(cfqd, gfp_mask); + cic = cfq_alloc_cic(cfqd, gfp_mask); if (!cic) goto out; + icq = &cic->icq; ret = radix_tree_preload(gfp_mask); if (ret) goto out; - cic->ioc = ioc; - cic->q = cfqd->queue; + icq->ioc = ioc; + icq->q = cfqd->queue; - /* lock both q and ioc and try to link @cic */ + /* lock both q and ioc and try to link @icq */ spin_lock_irq(q->queue_lock); spin_lock(&ioc->lock); - ret = radix_tree_insert(&ioc->radix_root, q->id, cic); + ret = radix_tree_insert(&ioc->icq_tree, q->id, icq); if (likely(!ret)) { - hlist_add_head(&cic->cic_list, &ioc->cic_list); - list_add(&cic->queue_list, &cfqd->cic_list); - cic = NULL; + hlist_add_head(&icq->ioc_node, &ioc->icq_list); + list_add(&icq->q_node, &cfqd->icq_list); + icq = NULL; } else if (ret == -EEXIST) { /* someone else already did it */ ret = 0; @@ -3047,29 +3066,28 @@ static int cfq_create_cic(struct cfq_data *cfqd, gfp_t gfp_mask) radix_tree_preload_end(); out: if (ret) - printk(KERN_ERR "cfq: cic link failed!\n"); - if (cic) - cfq_cic_free(cic); + printk(KERN_ERR "cfq: icq link failed!\n"); + if (icq) + cfq_icq_free(icq); return ret; } /** - * cfq_get_io_context - acquire cfq_io_context and bump refcnt on io_context + * cfq_get_cic - acquire cfq_io_cq and bump refcnt on io_context * @cfqd: cfqd to setup cic for * @gfp_mask: allocation mask * - * Return cfq_io_context associating @cfqd and %current->io_context and + * Return cfq_io_cq associating @cfqd and %current->io_context and * bump refcnt on io_context. If ioc or cic doesn't exist, they're created * using @gfp_mask. * * Must be called under queue_lock which may be released and re-acquired. * This function also may sleep depending on @gfp_mask. */ -static struct cfq_io_context * -cfq_get_io_context(struct cfq_data *cfqd, gfp_t gfp_mask) +static struct cfq_io_cq *cfq_get_cic(struct cfq_data *cfqd, gfp_t gfp_mask) { struct request_queue *q = cfqd->queue; - struct cfq_io_context *cic = NULL; + struct cfq_io_cq *cic = NULL; struct io_context *ioc; int err; @@ -3095,11 +3113,11 @@ cfq_get_io_context(struct cfq_data *cfqd, gfp_t gfp_mask) /* bump @ioc's refcnt and handle changed notifications */ get_io_context(ioc); - if (unlikely(cic->changed)) { - if (test_and_clear_bit(CIC_IOPRIO_CHANGED, &cic->changed)) + if (unlikely(cic->icq.changed)) { + if (test_and_clear_bit(ICQ_IOPRIO_CHANGED, &cic->icq.changed)) changed_ioprio(cic); #ifdef CONFIG_CFQ_GROUP_IOSCHED - if (test_and_clear_bit(CIC_CGROUP_CHANGED, &cic->changed)) + if (test_and_clear_bit(ICQ_CGROUP_CHANGED, &cic->icq.changed)) changed_cgroup(cic); #endif } @@ -3120,7 +3138,7 @@ __cfq_update_io_thinktime(struct cfq_ttime *ttime, unsigned long slice_idle) static void cfq_update_io_thinktime(struct cfq_data *cfqd, struct cfq_queue *cfqq, - struct cfq_io_context *cic) + struct cfq_io_cq *cic) { if (cfq_cfqq_sync(cfqq)) { __cfq_update_io_thinktime(&cic->ttime, cfqd->cfq_slice_idle); @@ -3158,7 +3176,7 @@ cfq_update_io_seektime(struct cfq_data *cfqd, struct cfq_queue *cfqq, */ static void cfq_update_idle_window(struct cfq_data *cfqd, struct cfq_queue *cfqq, - struct cfq_io_context *cic) + struct cfq_io_cq *cic) { int old_idle, enable_idle; @@ -3175,8 +3193,9 @@ cfq_update_idle_window(struct cfq_data *cfqd, struct cfq_queue *cfqq, if (cfqq->next_rq && (cfqq->next_rq->cmd_flags & REQ_NOIDLE)) enable_idle = 0; - else if (!atomic_read(&cic->ioc->nr_tasks) || !cfqd->cfq_slice_idle || - (!cfq_cfqq_deep(cfqq) && CFQQ_SEEKY(cfqq))) + else if (!atomic_read(&cic->icq.ioc->nr_tasks) || + !cfqd->cfq_slice_idle || + (!cfq_cfqq_deep(cfqq) && CFQQ_SEEKY(cfqq))) enable_idle = 0; else if (sample_valid(cic->ttime.ttime_samples)) { if (cic->ttime.ttime_mean > cfqd->cfq_slice_idle) @@ -3308,7 +3327,7 @@ static void cfq_rq_enqueued(struct cfq_data *cfqd, struct cfq_queue *cfqq, struct request *rq) { - struct cfq_io_context *cic = RQ_CIC(rq); + struct cfq_io_cq *cic = RQ_CIC(rq); cfqd->rq_queued++; if (rq->cmd_flags & REQ_PRIO) @@ -3361,7 +3380,7 @@ static void cfq_insert_request(struct request_queue *q, struct request *rq) struct cfq_queue *cfqq = RQ_CFQQ(rq); cfq_log_cfqq(cfqd, cfqq, "insert_request"); - cfq_init_prio_data(cfqq, RQ_CIC(rq)->ioc); + cfq_init_prio_data(cfqq, RQ_CIC(rq)->icq.ioc); rq_set_fifo_time(rq, jiffies + cfqd->cfq_fifo_expire[rq_is_sync(rq)]); list_add_tail(&rq->queuelist, &cfqq->fifo); @@ -3411,7 +3430,7 @@ static void cfq_update_hw_tag(struct cfq_data *cfqd) static bool cfq_should_wait_busy(struct cfq_data *cfqd, struct cfq_queue *cfqq) { - struct cfq_io_context *cic = cfqd->active_cic; + struct cfq_io_cq *cic = cfqd->active_cic; /* If the queue already has requests, don't wait */ if (!RB_EMPTY_ROOT(&cfqq->sort_list)) @@ -3548,7 +3567,7 @@ static int cfq_may_queue(struct request_queue *q, int rw) { struct cfq_data *cfqd = q->elevator->elevator_data; struct task_struct *tsk = current; - struct cfq_io_context *cic; + struct cfq_io_cq *cic; struct cfq_queue *cfqq; /* @@ -3563,7 +3582,7 @@ static int cfq_may_queue(struct request_queue *q, int rw) cfqq = cic_to_cfqq(cic, rw_is_sync(rw)); if (cfqq) { - cfq_init_prio_data(cfqq, cic->ioc); + cfq_init_prio_data(cfqq, cic->icq.ioc); return __cfq_may_queue(cfqq); } @@ -3584,7 +3603,7 @@ static void cfq_put_request(struct request *rq) BUG_ON(!cfqq->allocated[rw]); cfqq->allocated[rw]--; - put_io_context(RQ_CIC(rq)->ioc, cfqq->cfqd->queue); + put_io_context(RQ_CIC(rq)->icq.ioc, cfqq->cfqd->queue); rq->elevator_private[0] = NULL; rq->elevator_private[1] = NULL; @@ -3598,7 +3617,7 @@ static void cfq_put_request(struct request *rq) } static struct cfq_queue * -cfq_merge_cfqqs(struct cfq_data *cfqd, struct cfq_io_context *cic, +cfq_merge_cfqqs(struct cfq_data *cfqd, struct cfq_io_cq *cic, struct cfq_queue *cfqq) { cfq_log_cfqq(cfqd, cfqq, "merging with queue %p", cfqq->new_cfqq); @@ -3613,7 +3632,7 @@ cfq_merge_cfqqs(struct cfq_data *cfqd, struct cfq_io_context *cic, * was the last process referring to said cfqq. */ static struct cfq_queue * -split_cfqq(struct cfq_io_context *cic, struct cfq_queue *cfqq) +split_cfqq(struct cfq_io_cq *cic, struct cfq_queue *cfqq) { if (cfqq_process_refs(cfqq) == 1) { cfqq->pid = current->pid; @@ -3636,7 +3655,7 @@ static int cfq_set_request(struct request_queue *q, struct request *rq, gfp_t gfp_mask) { struct cfq_data *cfqd = q->elevator->elevator_data; - struct cfq_io_context *cic; + struct cfq_io_cq *cic; const int rw = rq_data_dir(rq); const bool is_sync = rq_is_sync(rq); struct cfq_queue *cfqq; @@ -3644,14 +3663,14 @@ cfq_set_request(struct request_queue *q, struct request *rq, gfp_t gfp_mask) might_sleep_if(gfp_mask & __GFP_WAIT); spin_lock_irq(q->queue_lock); - cic = cfq_get_io_context(cfqd, gfp_mask); + cic = cfq_get_cic(cfqd, gfp_mask); if (!cic) goto queue_fail; new_queue: cfqq = cic_to_cfqq(cic, is_sync); if (!cfqq || cfqq == &cfqd->oom_cfqq) { - cfqq = cfq_get_queue(cfqd, is_sync, cic->ioc, gfp_mask); + cfqq = cfq_get_queue(cfqd, is_sync, cic->icq.ioc, gfp_mask); cic_set_cfqq(cic, cfqq, is_sync); } else { /* @@ -3677,7 +3696,7 @@ new_queue: cfqq->allocated[rw]++; cfqq->ref++; - rq->elevator_private[0] = cic; + rq->elevator_private[0] = &cic->icq; rq->elevator_private[1] = cfqq; rq->elevator_private[2] = cfq_ref_get_cfqg(cfqq->cfqg); spin_unlock_irq(q->queue_lock); @@ -3791,15 +3810,14 @@ static void cfq_exit_queue(struct elevator_queue *e) if (cfqd->active_queue) __cfq_slice_expired(cfqd, cfqd->active_queue, 0); - while (!list_empty(&cfqd->cic_list)) { - struct cfq_io_context *cic = list_entry(cfqd->cic_list.next, - struct cfq_io_context, - queue_list); - struct io_context *ioc = cic->ioc; + while (!list_empty(&cfqd->icq_list)) { + struct io_cq *icq = list_entry(cfqd->icq_list.next, + struct io_cq, q_node); + struct io_context *ioc = icq->ioc; spin_lock(&ioc->lock); - cfq_exit_cic(cic); - cfq_release_cic(cic); + cfq_exit_icq(icq); + cfq_release_icq(icq); spin_unlock(&ioc->lock); } @@ -3904,7 +3922,7 @@ static void *cfq_init_queue(struct request_queue *q) cfqd->oom_cfqq.ref++; cfq_link_cfqq_cfqg(&cfqd->oom_cfqq, &cfqd->root_group); - INIT_LIST_HEAD(&cfqd->cic_list); + INIT_LIST_HEAD(&cfqd->icq_list); cfqd->queue = q; @@ -3942,8 +3960,8 @@ static void cfq_slab_kill(void) */ if (cfq_pool) kmem_cache_destroy(cfq_pool); - if (cfq_ioc_pool) - kmem_cache_destroy(cfq_ioc_pool); + if (cfq_icq_pool) + kmem_cache_destroy(cfq_icq_pool); } static int __init cfq_slab_setup(void) @@ -3952,8 +3970,8 @@ static int __init cfq_slab_setup(void) if (!cfq_pool) goto fail; - cfq_ioc_pool = KMEM_CACHE(cfq_io_context, 0); - if (!cfq_ioc_pool) + cfq_icq_pool = KMEM_CACHE(cfq_io_cq, 0); + if (!cfq_icq_pool) goto fail; return 0; diff --git a/include/linux/iocontext.h b/include/linux/iocontext.h index b2b75a54f252..d15ca6591f96 100644 --- a/include/linux/iocontext.h +++ b/include/linux/iocontext.h @@ -5,38 +5,23 @@ #include #include -struct cfq_queue; -struct cfq_ttime { - unsigned long last_end_request; - - unsigned long ttime_total; - unsigned long ttime_samples; - unsigned long ttime_mean; -}; - enum { - CIC_IOPRIO_CHANGED, - CIC_CGROUP_CHANGED, + ICQ_IOPRIO_CHANGED, + ICQ_CGROUP_CHANGED, }; -struct cfq_io_context { - struct request_queue *q; - - struct cfq_queue *cfqq[2]; - - struct io_context *ioc; - - struct cfq_ttime ttime; - - struct list_head queue_list; - struct hlist_node cic_list; +struct io_cq { + struct request_queue *q; + struct io_context *ioc; - unsigned long changed; + struct list_head q_node; + struct hlist_node ioc_node; - void (*exit)(struct cfq_io_context *); - void (*release)(struct cfq_io_context *); + unsigned long changed; + struct rcu_head rcu_head; - struct rcu_head rcu_head; + void (*exit)(struct io_cq *); + void (*release)(struct io_cq *); }; /* @@ -58,9 +43,9 @@ struct io_context { int nr_batch_requests; /* Number of requests left in the batch */ unsigned long last_waited; /* Time last woken after wait for request */ - struct radix_tree_root radix_root; - struct hlist_head cic_list; - void __rcu *ioc_data; + struct radix_tree_root icq_tree; + struct io_cq __rcu *icq_hint; + struct hlist_head icq_list; struct work_struct release_work; }; -- 2.39.5