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block/elevator.c
26.8 KB
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/* |
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* Block device elevator/IO-scheduler. * * Copyright (C) 2000 Andrea Arcangeli <andrea@suse.de> SuSE * |
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* 30042000 Jens Axboe <axboe@kernel.dk> : |
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* * Split the elevator a bit so that it is possible to choose a different * one or even write a new "plug in". There are three pieces: * - elevator_fn, inserts a new request in the queue list * - elevator_merge_fn, decides whether a new buffer can be merged with * an existing request * - elevator_dequeue_fn, called when a request is taken off the active list * * 20082000 Dave Jones <davej@suse.de> : * Removed tests for max-bomb-segments, which was breaking elvtune * when run without -bN * * Jens: * - Rework again to work with bio instead of buffer_heads * - loose bi_dev comparisons, partition handling is right now * - completely modularize elevator setup and teardown * */ #include <linux/kernel.h> #include <linux/fs.h> #include <linux/blkdev.h> #include <linux/elevator.h> #include <linux/bio.h> |
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#include <linux/module.h> #include <linux/slab.h> #include <linux/init.h> #include <linux/compiler.h> |
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#include <linux/blktrace_api.h> |
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#include <linux/hash.h> |
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#include <linux/uaccess.h> |
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#include <linux/pm_runtime.h> |
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#include <linux/blk-cgroup.h> |
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|
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#include <trace/events/block.h> |
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#include "blk.h" |
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#include "blk-mq-sched.h" |
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#include "blk-wbt.h" |
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|
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static DEFINE_SPINLOCK(elv_list_lock); static LIST_HEAD(elv_list); /* |
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* Merge hash stuff. */ |
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#define rq_hash_key(rq) (blk_rq_pos(rq) + blk_rq_sectors(rq)) |
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/* |
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* Query io scheduler to see if the current process issuing bio may be * merged with rq. */ |
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static int elv_iosched_allow_bio_merge(struct request *rq, struct bio *bio) |
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{ |
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struct request_queue *q = rq->q; |
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struct elevator_queue *e = q->elevator; |
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|
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if (e->uses_mq && e->type->ops.mq.allow_merge) return e->type->ops.mq.allow_merge(q, rq, bio); else if (!e->uses_mq && e->type->ops.sq.elevator_allow_bio_merge_fn) |
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return e->type->ops.sq.elevator_allow_bio_merge_fn(q, rq, bio); |
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return 1; } /* |
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* can we safely merge with this request? */ |
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bool elv_bio_merge_ok(struct request *rq, struct bio *bio) |
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{ |
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if (!blk_rq_merge_ok(rq, bio)) |
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return false; |
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|
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if (!elv_iosched_allow_bio_merge(rq, bio)) return false; |
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|
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return true; |
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} |
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EXPORT_SYMBOL(elv_bio_merge_ok); |
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|
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static struct elevator_type *elevator_find(const char *name) { |
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struct elevator_type *e; |
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|
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list_for_each_entry(e, &elv_list, list) { |
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if (!strcmp(e->elevator_name, name)) return e; |
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} |
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|
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return NULL; |
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} static void elevator_put(struct elevator_type *e) { module_put(e->elevator_owner); } |
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static struct elevator_type *elevator_get(const char *name, bool try_loading) |
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{ |
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struct elevator_type *e; |
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|
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spin_lock(&elv_list_lock); |
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e = elevator_find(name); |
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if (!e && try_loading) { |
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spin_unlock(&elv_list_lock); |
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request_module("%s-iosched", name); |
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spin_lock(&elv_list_lock); e = elevator_find(name); } |
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if (e && !try_module_get(e->elevator_owner)) e = NULL; |
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spin_unlock(&elv_list_lock); |
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return e; } |
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static char chosen_elevator[ELV_NAME_MAX]; |
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|
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static int __init elevator_setup(char *str) |
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{ |
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/* * Be backwards-compatible with previous kernels, so users * won't get the wrong elevator. */ |
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strncpy(chosen_elevator, str, sizeof(chosen_elevator) - 1); |
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return 1; |
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} __setup("elevator=", elevator_setup); |
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/* called during boot to load the elevator chosen by the elevator param */ void __init load_default_elevator_module(void) { struct elevator_type *e; if (!chosen_elevator[0]) return; spin_lock(&elv_list_lock); e = elevator_find(chosen_elevator); spin_unlock(&elv_list_lock); if (!e) request_module("%s-iosched", chosen_elevator); } |
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static struct kobj_type elv_ktype; |
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struct elevator_queue *elevator_alloc(struct request_queue *q, |
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struct elevator_type *e) |
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{ |
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struct elevator_queue *eq; |
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|
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eq = kzalloc_node(sizeof(*eq), GFP_KERNEL, q->node); |
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if (unlikely(!eq)) |
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return NULL; |
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|
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eq->type = e; |
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kobject_init(&eq->kobj, &elv_ktype); |
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mutex_init(&eq->sysfs_lock); |
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hash_init(eq->hash); |
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eq->uses_mq = e->uses_mq; |
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|
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return eq; } |
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EXPORT_SYMBOL(elevator_alloc); |
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static void elevator_release(struct kobject *kobj) { |
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struct elevator_queue *e; |
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|
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e = container_of(kobj, struct elevator_queue, kobj); |
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elevator_put(e->type); |
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kfree(e); } |
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int elevator_init(struct request_queue *q, char *name) |
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{ struct elevator_type *e = NULL; |
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int err; |
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|
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/* * q->sysfs_lock must be held to provide mutual exclusion between * elevator_switch() and here. */ lockdep_assert_held(&q->sysfs_lock); |
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if (unlikely(q->elevator)) return 0; |
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INIT_LIST_HEAD(&q->queue_head); q->last_merge = NULL; q->end_sector = 0; q->boundary_rq = NULL; |
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|
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if (name) { |
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e = elevator_get(name, true); |
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if (!e) return -EINVAL; } |
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|
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/* |
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* Use the default elevator specified by config boot param for * non-mq devices, or by config option. Don't try to load modules * as we could be running off async and request_module() isn't * allowed from async. |
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*/ |
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if (!e && !q->mq_ops && *chosen_elevator) { |
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e = elevator_get(chosen_elevator, false); |
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if (!e) printk(KERN_ERR "I/O scheduler %s not found ", chosen_elevator); } |
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|
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if (!e) { |
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/* * For blk-mq devices, we default to using mq-deadline, * if available, for single queue devices. If deadline * isn't available OR we have multiple queues, default * to "none". */ if (q->mq_ops) { if (q->nr_hw_queues == 1) e = elevator_get("mq-deadline", false); if (!e) return 0; } else |
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e = elevator_get(CONFIG_DEFAULT_IOSCHED, false); |
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if (!e) { printk(KERN_ERR "Default I/O scheduler not found. " \ |
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"Using noop. "); |
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e = elevator_get("noop", false); |
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} |
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} |
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if (e->uses_mq) err = blk_mq_init_sched(q, e); else |
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err = e->ops.sq.elevator_init_fn(q, e); |
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if (err) |
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elevator_put(e); return err; |
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} |
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EXPORT_SYMBOL(elevator_init); |
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void elevator_exit(struct request_queue *q, struct elevator_queue *e) |
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{ |
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mutex_lock(&e->sysfs_lock); |
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if (e->uses_mq && e->type->ops.mq.exit_sched) |
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blk_mq_exit_sched(q, e); |
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else if (!e->uses_mq && e->type->ops.sq.elevator_exit_fn) |
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e->type->ops.sq.elevator_exit_fn(e); |
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mutex_unlock(&e->sysfs_lock); |
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|
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kobject_put(&e->kobj); |
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} |
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EXPORT_SYMBOL(elevator_exit); |
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static inline void __elv_rqhash_del(struct request *rq) { |
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hash_del(&rq->hash); |
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rq->rq_flags &= ~RQF_HASHED; |
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} |
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void elv_rqhash_del(struct request_queue *q, struct request *rq) |
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{ if (ELV_ON_HASH(rq)) __elv_rqhash_del(rq); } |
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EXPORT_SYMBOL_GPL(elv_rqhash_del); |
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|
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void elv_rqhash_add(struct request_queue *q, struct request *rq) |
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{ |
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struct elevator_queue *e = q->elevator; |
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BUG_ON(ELV_ON_HASH(rq)); |
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hash_add(e->hash, &rq->hash, rq_hash_key(rq)); |
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rq->rq_flags |= RQF_HASHED; |
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} |
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EXPORT_SYMBOL_GPL(elv_rqhash_add); |
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|
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void elv_rqhash_reposition(struct request_queue *q, struct request *rq) |
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{ __elv_rqhash_del(rq); elv_rqhash_add(q, rq); } |
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struct request *elv_rqhash_find(struct request_queue *q, sector_t offset) |
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{ |
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struct elevator_queue *e = q->elevator; |
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struct hlist_node *next; |
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struct request *rq; |
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hash_for_each_possible_safe(e->hash, rq, next, hash, offset) { |
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BUG_ON(!ELV_ON_HASH(rq)); if (unlikely(!rq_mergeable(rq))) { __elv_rqhash_del(rq); continue; } if (rq_hash_key(rq) == offset) return rq; } return NULL; } |
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/* |
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* RB-tree support functions for inserting/lookup/removal of requests * in a sorted RB tree. */ |
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void elv_rb_add(struct rb_root *root, struct request *rq) |
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{ struct rb_node **p = &root->rb_node; struct rb_node *parent = NULL; struct request *__rq; while (*p) { parent = *p; __rq = rb_entry(parent, struct request, rb_node); |
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if (blk_rq_pos(rq) < blk_rq_pos(__rq)) |
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p = &(*p)->rb_left; |
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else if (blk_rq_pos(rq) >= blk_rq_pos(__rq)) |
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p = &(*p)->rb_right; |
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} rb_link_node(&rq->rb_node, parent, p); rb_insert_color(&rq->rb_node, root); |
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} |
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EXPORT_SYMBOL(elv_rb_add); void elv_rb_del(struct rb_root *root, struct request *rq) { BUG_ON(RB_EMPTY_NODE(&rq->rb_node)); rb_erase(&rq->rb_node, root); RB_CLEAR_NODE(&rq->rb_node); } |
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EXPORT_SYMBOL(elv_rb_del); struct request *elv_rb_find(struct rb_root *root, sector_t sector) { struct rb_node *n = root->rb_node; struct request *rq; while (n) { rq = rb_entry(n, struct request, rb_node); |
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if (sector < blk_rq_pos(rq)) |
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n = n->rb_left; |
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else if (sector > blk_rq_pos(rq)) |
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n = n->rb_right; else return rq; } return NULL; } |
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EXPORT_SYMBOL(elv_rb_find); /* |
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* Insert rq into dispatch queue of q. Queue lock must be held on |
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* entry. rq is sort instead into the dispatch queue. To be used by |
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* specific elevators. |
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*/ |
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void elv_dispatch_sort(struct request_queue *q, struct request *rq) |
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{ sector_t boundary; |
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struct list_head *entry; |
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if (q->last_merge == rq) q->last_merge = NULL; |
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elv_rqhash_del(q, rq); |
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q->nr_sorted--; |
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|
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boundary = q->end_sector; |
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list_for_each_prev(entry, &q->queue_head) { struct request *pos = list_entry_rq(entry); |
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if (req_op(rq) != req_op(pos)) |
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break; |
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if (rq_data_dir(rq) != rq_data_dir(pos)) break; |
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if (pos->rq_flags & (RQF_STARTED | RQF_SOFTBARRIER)) |
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break; |
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if (blk_rq_pos(rq) >= boundary) { if (blk_rq_pos(pos) < boundary) |
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continue; } else { |
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if (blk_rq_pos(pos) >= boundary) |
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break; } |
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if (blk_rq_pos(rq) >= blk_rq_pos(pos)) |
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break; } list_add(&rq->queuelist, entry); } |
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EXPORT_SYMBOL(elv_dispatch_sort); |
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/* |
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* Insert rq into dispatch queue of q. Queue lock must be held on * entry. rq is added to the back of the dispatch queue. To be used by * specific elevators. |
9817064b6 [PATCH] elevator:... |
395 396 397 398 399 400 401 402 403 404 405 406 407 408 |
*/ void elv_dispatch_add_tail(struct request_queue *q, struct request *rq) { if (q->last_merge == rq) q->last_merge = NULL; elv_rqhash_del(q, rq); q->nr_sorted--; q->end_sector = rq_end_sector(rq); q->boundary_rq = rq; list_add_tail(&rq->queuelist, &q->queue_head); } |
2e662b65f [PATCH] elevator:... |
409 |
EXPORT_SYMBOL(elv_dispatch_add_tail); |
34fe7c054 block: enumify EL... |
410 411 |
enum elv_merge elv_merge(struct request_queue *q, struct request **req, struct bio *bio) |
1da177e4c Linux-2.6.12-rc2 |
412 |
{ |
b374d18a4 block: get rid of... |
413 |
struct elevator_queue *e = q->elevator; |
9817064b6 [PATCH] elevator:... |
414 |
struct request *__rq; |
06b86245c [PATCH] 03/05 mov... |
415 |
|
9817064b6 [PATCH] elevator:... |
416 |
/* |
488991e28 block: Added in s... |
417 418 419 420 421 |
* Levels of merges: * nomerges: No merges at all attempted * noxmerges: Only simple one-hit cache try * merges: All merge tries attempted */ |
7460d389c block: check bio_... |
422 |
if (blk_queue_nomerges(q) || !bio_mergeable(bio)) |
488991e28 block: Added in s... |
423 424 425 |
return ELEVATOR_NO_MERGE; /* |
9817064b6 [PATCH] elevator:... |
426 427 |
* First try one-hit cache. */ |
72ef799b3 block: do not mer... |
428 |
if (q->last_merge && elv_bio_merge_ok(q->last_merge, bio)) { |
34fe7c054 block: enumify EL... |
429 |
enum elv_merge ret = blk_try_merge(q->last_merge, bio); |
06b86245c [PATCH] 03/05 mov... |
430 431 432 433 434 |
if (ret != ELEVATOR_NO_MERGE) { *req = q->last_merge; return ret; } } |
1da177e4c Linux-2.6.12-rc2 |
435 |
|
488991e28 block: Added in s... |
436 |
if (blk_queue_noxmerges(q)) |
ac9fafa12 block: Skip I/O m... |
437 |
return ELEVATOR_NO_MERGE; |
9817064b6 [PATCH] elevator:... |
438 439 440 |
/* * See if our hash lookup can find a potential backmerge. */ |
4f024f379 block: Abstract o... |
441 |
__rq = elv_rqhash_find(q, bio->bi_iter.bi_sector); |
72ef799b3 block: do not mer... |
442 |
if (__rq && elv_bio_merge_ok(__rq, bio)) { |
9817064b6 [PATCH] elevator:... |
443 444 445 |
*req = __rq; return ELEVATOR_BACK_MERGE; } |
bd166ef18 blk-mq-sched: add... |
446 447 448 |
if (e->uses_mq && e->type->ops.mq.request_merge) return e->type->ops.mq.request_merge(q, req, bio); else if (!e->uses_mq && e->type->ops.sq.elevator_merge_fn) |
c51ca6cf5 block: move exist... |
449 |
return e->type->ops.sq.elevator_merge_fn(q, req, bio); |
1da177e4c Linux-2.6.12-rc2 |
450 451 452 |
return ELEVATOR_NO_MERGE; } |
5e84ea3a9 block: attempt to... |
453 454 455 456 457 458 459 |
/* * Attempt to do an insertion back merge. Only check for the case where * we can append 'rq' to an existing request, so we can throw 'rq' away * afterwards. * * Returns true if we merged, false otherwise */ |
bd166ef18 blk-mq-sched: add... |
460 |
bool elv_attempt_insert_merge(struct request_queue *q, struct request *rq) |
5e84ea3a9 block: attempt to... |
461 462 |
{ struct request *__rq; |
bee0393cc block: recursive ... |
463 |
bool ret; |
5e84ea3a9 block: attempt to... |
464 465 466 467 468 469 470 471 472 473 474 475 |
if (blk_queue_nomerges(q)) return false; /* * First try one-hit cache. */ if (q->last_merge && blk_attempt_req_merge(q, q->last_merge, rq)) return true; if (blk_queue_noxmerges(q)) return false; |
bee0393cc block: recursive ... |
476 |
ret = false; |
5e84ea3a9 block: attempt to... |
477 478 479 |
/* * See if our hash lookup can find a potential backmerge. */ |
bee0393cc block: recursive ... |
480 481 482 483 484 485 486 487 488 |
while (1) { __rq = elv_rqhash_find(q, blk_rq_pos(rq)); if (!__rq || !blk_attempt_req_merge(q, __rq, rq)) break; /* The merged request could be merged with others, try again */ ret = true; rq = __rq; } |
274193224 block: recursive ... |
489 |
|
bee0393cc block: recursive ... |
490 |
return ret; |
5e84ea3a9 block: attempt to... |
491 |
} |
34fe7c054 block: enumify EL... |
492 493 |
void elv_merged_request(struct request_queue *q, struct request *rq, enum elv_merge type) |
1da177e4c Linux-2.6.12-rc2 |
494 |
{ |
b374d18a4 block: get rid of... |
495 |
struct elevator_queue *e = q->elevator; |
1da177e4c Linux-2.6.12-rc2 |
496 |
|
bd166ef18 blk-mq-sched: add... |
497 498 499 |
if (e->uses_mq && e->type->ops.mq.request_merged) e->type->ops.mq.request_merged(q, rq, type); else if (!e->uses_mq && e->type->ops.sq.elevator_merged_fn) |
c51ca6cf5 block: move exist... |
500 |
e->type->ops.sq.elevator_merged_fn(q, rq, type); |
06b86245c [PATCH] 03/05 mov... |
501 |
|
2e662b65f [PATCH] elevator:... |
502 503 |
if (type == ELEVATOR_BACK_MERGE) elv_rqhash_reposition(q, rq); |
9817064b6 [PATCH] elevator:... |
504 |
|
06b86245c [PATCH] 03/05 mov... |
505 |
q->last_merge = rq; |
1da177e4c Linux-2.6.12-rc2 |
506 |
} |
165125e1e [BLOCK] Get rid o... |
507 |
void elv_merge_requests(struct request_queue *q, struct request *rq, |
1da177e4c Linux-2.6.12-rc2 |
508 509 |
struct request *next) { |
b374d18a4 block: get rid of... |
510 |
struct elevator_queue *e = q->elevator; |
bd166ef18 blk-mq-sched: add... |
511 512 513 514 515 |
bool next_sorted = false; if (e->uses_mq && e->type->ops.mq.requests_merged) e->type->ops.mq.requests_merged(q, rq, next); else if (e->type->ops.sq.elevator_merge_req_fn) { |
a1ae0f74a blk-mq-debug: Avo... |
516 |
next_sorted = (__force bool)(next->rq_flags & RQF_SORTED); |
bd166ef18 blk-mq-sched: add... |
517 518 519 |
if (next_sorted) e->type->ops.sq.elevator_merge_req_fn(q, rq, next); } |
06b86245c [PATCH] 03/05 mov... |
520 |
|
9817064b6 [PATCH] elevator:... |
521 |
elv_rqhash_reposition(q, rq); |
9817064b6 [PATCH] elevator:... |
522 |
|
5e84ea3a9 block: attempt to... |
523 524 525 526 |
if (next_sorted) { elv_rqhash_del(q, next); q->nr_sorted--; } |
06b86245c [PATCH] 03/05 mov... |
527 |
q->last_merge = rq; |
1da177e4c Linux-2.6.12-rc2 |
528 |
} |
812d40264 blkio: Add io_mer... |
529 530 531 532 |
void elv_bio_merged(struct request_queue *q, struct request *rq, struct bio *bio) { struct elevator_queue *e = q->elevator; |
bd166ef18 blk-mq-sched: add... |
533 534 |
if (WARN_ON_ONCE(e->uses_mq)) return; |
c51ca6cf5 block: move exist... |
535 536 |
if (e->type->ops.sq.elevator_bio_merged_fn) e->type->ops.sq.elevator_bio_merged_fn(q, rq, bio); |
812d40264 blkio: Add io_mer... |
537 |
} |
47fafbc70 block / PM: Repla... |
538 |
#ifdef CONFIG_PM |
c8158819d block: implement ... |
539 540 |
static void blk_pm_requeue_request(struct request *rq) { |
e80640213 block: split out ... |
541 |
if (rq->q->dev && !(rq->rq_flags & RQF_PM)) |
c8158819d block: implement ... |
542 543 544 545 546 |
rq->q->nr_pending--; } static void blk_pm_add_request(struct request_queue *q, struct request *rq) { |
e80640213 block: split out ... |
547 |
if (q->dev && !(rq->rq_flags & RQF_PM) && q->nr_pending++ == 0 && |
c8158819d block: implement ... |
548 549 550 551 552 553 554 555 556 557 |
(q->rpm_status == RPM_SUSPENDED || q->rpm_status == RPM_SUSPENDING)) pm_request_resume(q->dev); } #else static inline void blk_pm_requeue_request(struct request *rq) {} static inline void blk_pm_add_request(struct request_queue *q, struct request *rq) { } #endif |
165125e1e [BLOCK] Get rid o... |
558 |
void elv_requeue_request(struct request_queue *q, struct request *rq) |
1da177e4c Linux-2.6.12-rc2 |
559 |
{ |
1da177e4c Linux-2.6.12-rc2 |
560 561 562 563 |
/* * it already went through dequeue, we need to decrement the * in_flight count again */ |
8922e16cf [PATCH] 01/05 Imp... |
564 |
if (blk_account_rq(rq)) { |
0a7ae2ff0 block: change the... |
565 |
q->in_flight[rq_is_sync(rq)]--; |
e80640213 block: split out ... |
566 |
if (rq->rq_flags & RQF_SORTED) |
cad975164 elevator: abstrac... |
567 |
elv_deactivate_rq(q, rq); |
8922e16cf [PATCH] 01/05 Imp... |
568 |
} |
1da177e4c Linux-2.6.12-rc2 |
569 |
|
e80640213 block: split out ... |
570 |
rq->rq_flags &= ~RQF_STARTED; |
1da177e4c Linux-2.6.12-rc2 |
571 |
|
c8158819d block: implement ... |
572 |
blk_pm_requeue_request(rq); |
b710a4805 block: get rid of... |
573 |
__elv_add_request(q, rq, ELEVATOR_INSERT_REQUEUE); |
1da177e4c Linux-2.6.12-rc2 |
574 |
} |
26308eab6 block: fix incons... |
575 |
void elv_drain_elevator(struct request_queue *q) |
15853af9f [BLOCK] Implement... |
576 |
{ |
bd166ef18 blk-mq-sched: add... |
577 |
struct elevator_queue *e = q->elevator; |
15853af9f [BLOCK] Implement... |
578 |
static int printed; |
e3c78ca52 block: reorganize... |
579 |
|
bd166ef18 blk-mq-sched: add... |
580 581 |
if (WARN_ON_ONCE(e->uses_mq)) return; |
e3c78ca52 block: reorganize... |
582 |
lockdep_assert_held(q->queue_lock); |
bd166ef18 blk-mq-sched: add... |
583 |
while (e->type->ops.sq.elevator_dispatch_fn(q, 1)) |
15853af9f [BLOCK] Implement... |
584 |
; |
e3c78ca52 block: reorganize... |
585 |
if (q->nr_sorted && printed++ < 10) { |
15853af9f [BLOCK] Implement... |
586 587 588 |
printk(KERN_ERR "%s: forced dispatching is broken " "(nr_sorted=%u), please report this ", |
22f746e23 block: remove ele... |
589 |
q->elevator->type->elevator_name, q->nr_sorted); |
15853af9f [BLOCK] Implement... |
590 591 |
} } |
b710a4805 block: get rid of... |
592 |
void __elv_add_request(struct request_queue *q, struct request *rq, int where) |
1da177e4c Linux-2.6.12-rc2 |
593 |
{ |
5f3ea37c7 blktrace: port to... |
594 |
trace_block_rq_insert(q, rq); |
2056a782f [PATCH] Block que... |
595 |
|
c8158819d block: implement ... |
596 |
blk_pm_add_request(q, rq); |
1da177e4c Linux-2.6.12-rc2 |
597 |
rq->q = q; |
e80640213 block: split out ... |
598 |
if (rq->rq_flags & RQF_SOFTBARRIER) { |
b710a4805 block: get rid of... |
599 |
/* barriers are scheduling boundary, update end_sector */ |
57292b58d block: introduce ... |
600 |
if (!blk_rq_is_passthrough(rq)) { |
b710a4805 block: get rid of... |
601 602 603 |
q->end_sector = rq_end_sector(rq); q->boundary_rq = rq; } |
e80640213 block: split out ... |
604 |
} else if (!(rq->rq_flags & RQF_ELVPRIV) && |
3aa72873f elevator: check f... |
605 606 |
(where == ELEVATOR_INSERT_SORT || where == ELEVATOR_INSERT_SORT_MERGE)) |
b710a4805 block: get rid of... |
607 |
where = ELEVATOR_INSERT_BACK; |
8922e16cf [PATCH] 01/05 Imp... |
608 |
switch (where) { |
28e7d1845 block: drop barri... |
609 |
case ELEVATOR_INSERT_REQUEUE: |
8922e16cf [PATCH] 01/05 Imp... |
610 |
case ELEVATOR_INSERT_FRONT: |
e80640213 block: split out ... |
611 |
rq->rq_flags |= RQF_SOFTBARRIER; |
8922e16cf [PATCH] 01/05 Imp... |
612 613 614 615 |
list_add(&rq->queuelist, &q->queue_head); break; case ELEVATOR_INSERT_BACK: |
e80640213 block: split out ... |
616 |
rq->rq_flags |= RQF_SOFTBARRIER; |
15853af9f [BLOCK] Implement... |
617 |
elv_drain_elevator(q); |
8922e16cf [PATCH] 01/05 Imp... |
618 619 620 621 622 623 624 625 626 627 628 |
list_add_tail(&rq->queuelist, &q->queue_head); /* * We kick the queue here for the following reasons. * - The elevator might have returned NULL previously * to delay requests and returned them now. As the * queue wasn't empty before this request, ll_rw_blk * won't run the queue on return, resulting in hang. * - Usually, back inserted requests won't be merged * with anything. There's no point in delaying queue * processing. */ |
24ecfbe27 block: add blk_ru... |
629 |
__blk_run_queue(q); |
8922e16cf [PATCH] 01/05 Imp... |
630 |
break; |
5e84ea3a9 block: attempt to... |
631 632 633 634 635 636 637 638 |
case ELEVATOR_INSERT_SORT_MERGE: /* * If we succeed in merging this request with one in the * queue already, we are done - rq has now been freed, * so no need to do anything further. */ if (elv_attempt_insert_merge(q, rq)) break; |
e29387ebd block: Add fallth... |
639 |
/* fall through */ |
8922e16cf [PATCH] 01/05 Imp... |
640 |
case ELEVATOR_INSERT_SORT: |
57292b58d block: introduce ... |
641 |
BUG_ON(blk_rq_is_passthrough(rq)); |
e80640213 block: split out ... |
642 |
rq->rq_flags |= RQF_SORTED; |
15853af9f [BLOCK] Implement... |
643 |
q->nr_sorted++; |
9817064b6 [PATCH] elevator:... |
644 645 646 647 648 |
if (rq_mergeable(rq)) { elv_rqhash_add(q, rq); if (!q->last_merge) q->last_merge = rq; } |
ca23509fb [PATCH] blk: fix ... |
649 650 651 652 653 |
/* * Some ioscheds (cfq) run q->request_fn directly, so * rq cannot be accessed after calling * elevator_add_req_fn. */ |
c51ca6cf5 block: move exist... |
654 |
q->elevator->type->ops.sq.elevator_add_req_fn(q, rq); |
8922e16cf [PATCH] 01/05 Imp... |
655 |
break; |
ae1b15396 block: reimplemen... |
656 |
case ELEVATOR_INSERT_FLUSH: |
e80640213 block: split out ... |
657 |
rq->rq_flags |= RQF_SOFTBARRIER; |
ae1b15396 block: reimplemen... |
658 659 |
blk_insert_flush(rq); break; |
8922e16cf [PATCH] 01/05 Imp... |
660 661 662 |
default: printk(KERN_ERR "%s: bad insertion point %d ", |
24c03d47d block: remove rem... |
663 |
__func__, where); |
8922e16cf [PATCH] 01/05 Imp... |
664 665 |
BUG(); } |
1da177e4c Linux-2.6.12-rc2 |
666 |
} |
2e662b65f [PATCH] elevator:... |
667 |
EXPORT_SYMBOL(__elv_add_request); |
7eaceacca block: remove per... |
668 |
void elv_add_request(struct request_queue *q, struct request *rq, int where) |
1da177e4c Linux-2.6.12-rc2 |
669 670 671 672 |
{ unsigned long flags; spin_lock_irqsave(q->queue_lock, flags); |
7eaceacca block: remove per... |
673 |
__elv_add_request(q, rq, where); |
1da177e4c Linux-2.6.12-rc2 |
674 675 |
spin_unlock_irqrestore(q->queue_lock, flags); } |
2e662b65f [PATCH] elevator:... |
676 |
EXPORT_SYMBOL(elv_add_request); |
165125e1e [BLOCK] Get rid o... |
677 |
struct request *elv_latter_request(struct request_queue *q, struct request *rq) |
1da177e4c Linux-2.6.12-rc2 |
678 |
{ |
b374d18a4 block: get rid of... |
679 |
struct elevator_queue *e = q->elevator; |
1da177e4c Linux-2.6.12-rc2 |
680 |
|
bd166ef18 blk-mq-sched: add... |
681 682 683 |
if (e->uses_mq && e->type->ops.mq.next_request) return e->type->ops.mq.next_request(q, rq); else if (!e->uses_mq && e->type->ops.sq.elevator_latter_req_fn) |
c51ca6cf5 block: move exist... |
684 |
return e->type->ops.sq.elevator_latter_req_fn(q, rq); |
bd166ef18 blk-mq-sched: add... |
685 |
|
1da177e4c Linux-2.6.12-rc2 |
686 687 |
return NULL; } |
165125e1e [BLOCK] Get rid o... |
688 |
struct request *elv_former_request(struct request_queue *q, struct request *rq) |
1da177e4c Linux-2.6.12-rc2 |
689 |
{ |
b374d18a4 block: get rid of... |
690 |
struct elevator_queue *e = q->elevator; |
1da177e4c Linux-2.6.12-rc2 |
691 |
|
bd166ef18 blk-mq-sched: add... |
692 693 694 |
if (e->uses_mq && e->type->ops.mq.former_request) return e->type->ops.mq.former_request(q, rq); if (!e->uses_mq && e->type->ops.sq.elevator_former_req_fn) |
c51ca6cf5 block: move exist... |
695 |
return e->type->ops.sq.elevator_former_req_fn(q, rq); |
1da177e4c Linux-2.6.12-rc2 |
696 697 |
return NULL; } |
852c788f8 block: implement ... |
698 699 |
int elv_set_request(struct request_queue *q, struct request *rq, struct bio *bio, gfp_t gfp_mask) |
1da177e4c Linux-2.6.12-rc2 |
700 |
{ |
b374d18a4 block: get rid of... |
701 |
struct elevator_queue *e = q->elevator; |
1da177e4c Linux-2.6.12-rc2 |
702 |
|
bd166ef18 blk-mq-sched: add... |
703 704 |
if (WARN_ON_ONCE(e->uses_mq)) return 0; |
c51ca6cf5 block: move exist... |
705 706 |
if (e->type->ops.sq.elevator_set_req_fn) return e->type->ops.sq.elevator_set_req_fn(q, rq, bio, gfp_mask); |
1da177e4c Linux-2.6.12-rc2 |
707 708 |
return 0; } |
165125e1e [BLOCK] Get rid o... |
709 |
void elv_put_request(struct request_queue *q, struct request *rq) |
1da177e4c Linux-2.6.12-rc2 |
710 |
{ |
b374d18a4 block: get rid of... |
711 |
struct elevator_queue *e = q->elevator; |
1da177e4c Linux-2.6.12-rc2 |
712 |
|
bd166ef18 blk-mq-sched: add... |
713 714 |
if (WARN_ON_ONCE(e->uses_mq)) return; |
c51ca6cf5 block: move exist... |
715 716 |
if (e->type->ops.sq.elevator_put_req_fn) e->type->ops.sq.elevator_put_req_fn(rq); |
1da177e4c Linux-2.6.12-rc2 |
717 |
} |
ef295ecf0 block: better op ... |
718 |
int elv_may_queue(struct request_queue *q, unsigned int op) |
1da177e4c Linux-2.6.12-rc2 |
719 |
{ |
b374d18a4 block: get rid of... |
720 |
struct elevator_queue *e = q->elevator; |
1da177e4c Linux-2.6.12-rc2 |
721 |
|
bd166ef18 blk-mq-sched: add... |
722 723 |
if (WARN_ON_ONCE(e->uses_mq)) return 0; |
c51ca6cf5 block: move exist... |
724 725 |
if (e->type->ops.sq.elevator_may_queue_fn) return e->type->ops.sq.elevator_may_queue_fn(q, op); |
1da177e4c Linux-2.6.12-rc2 |
726 727 728 |
return ELV_MQUEUE_MAY; } |
165125e1e [BLOCK] Get rid o... |
729 |
void elv_completed_request(struct request_queue *q, struct request *rq) |
1da177e4c Linux-2.6.12-rc2 |
730 |
{ |
b374d18a4 block: get rid of... |
731 |
struct elevator_queue *e = q->elevator; |
1da177e4c Linux-2.6.12-rc2 |
732 |
|
bd166ef18 blk-mq-sched: add... |
733 734 |
if (WARN_ON_ONCE(e->uses_mq)) return; |
1da177e4c Linux-2.6.12-rc2 |
735 736 737 |
/* * request is released from the driver, io must be done */ |
8922e16cf [PATCH] 01/05 Imp... |
738 |
if (blk_account_rq(rq)) { |
0a7ae2ff0 block: change the... |
739 |
q->in_flight[rq_is_sync(rq)]--; |
e80640213 block: split out ... |
740 |
if ((rq->rq_flags & RQF_SORTED) && |
c51ca6cf5 block: move exist... |
741 742 |
e->type->ops.sq.elevator_completed_req_fn) e->type->ops.sq.elevator_completed_req_fn(q, rq); |
1bc691d35 [PATCH] fix queue... |
743 |
} |
1da177e4c Linux-2.6.12-rc2 |
744 |
} |
3d1ab40f4 [PATCH] elevator_... |
745 746 747 748 |
#define to_elv(atr) container_of((atr), struct elv_fs_entry, attr) static ssize_t elv_attr_show(struct kobject *kobj, struct attribute *attr, char *page) |
1da177e4c Linux-2.6.12-rc2 |
749 |
{ |
3d1ab40f4 [PATCH] elevator_... |
750 |
struct elv_fs_entry *entry = to_elv(attr); |
b374d18a4 block: get rid of... |
751 |
struct elevator_queue *e; |
3d1ab40f4 [PATCH] elevator_... |
752 753 754 755 |
ssize_t error; if (!entry->show) return -EIO; |
b374d18a4 block: get rid of... |
756 |
e = container_of(kobj, struct elevator_queue, kobj); |
3d1ab40f4 [PATCH] elevator_... |
757 |
mutex_lock(&e->sysfs_lock); |
22f746e23 block: remove ele... |
758 |
error = e->type ? entry->show(e, page) : -ENOENT; |
3d1ab40f4 [PATCH] elevator_... |
759 760 761 |
mutex_unlock(&e->sysfs_lock); return error; } |
1da177e4c Linux-2.6.12-rc2 |
762 |
|
3d1ab40f4 [PATCH] elevator_... |
763 764 765 766 |
static ssize_t elv_attr_store(struct kobject *kobj, struct attribute *attr, const char *page, size_t length) { |
3d1ab40f4 [PATCH] elevator_... |
767 |
struct elv_fs_entry *entry = to_elv(attr); |
b374d18a4 block: get rid of... |
768 |
struct elevator_queue *e; |
3d1ab40f4 [PATCH] elevator_... |
769 |
ssize_t error; |
1da177e4c Linux-2.6.12-rc2 |
770 |
|
3d1ab40f4 [PATCH] elevator_... |
771 772 |
if (!entry->store) return -EIO; |
1da177e4c Linux-2.6.12-rc2 |
773 |
|
b374d18a4 block: get rid of... |
774 |
e = container_of(kobj, struct elevator_queue, kobj); |
3d1ab40f4 [PATCH] elevator_... |
775 |
mutex_lock(&e->sysfs_lock); |
22f746e23 block: remove ele... |
776 |
error = e->type ? entry->store(e, page, length) : -ENOENT; |
3d1ab40f4 [PATCH] elevator_... |
777 778 779 |
mutex_unlock(&e->sysfs_lock); return error; } |
52cf25d0a Driver core: Cons... |
780 |
static const struct sysfs_ops elv_sysfs_ops = { |
3d1ab40f4 [PATCH] elevator_... |
781 782 783 784 785 786 787 788 |
.show = elv_attr_show, .store = elv_attr_store, }; static struct kobj_type elv_ktype = { .sysfs_ops = &elv_sysfs_ops, .release = elevator_release, }; |
5a5bafdc3 elevator: clear a... |
789 |
int elv_register_queue(struct request_queue *q) |
3d1ab40f4 [PATCH] elevator_... |
790 |
{ |
5a5bafdc3 elevator: clear a... |
791 |
struct elevator_queue *e = q->elevator; |
3d1ab40f4 [PATCH] elevator_... |
792 |
int error; |
b2d6db587 Kobject: rename k... |
793 |
error = kobject_add(&e->kobj, &q->kobj, "%s", "iosched"); |
3d1ab40f4 [PATCH] elevator_... |
794 |
if (!error) { |
22f746e23 block: remove ele... |
795 |
struct elv_fs_entry *attr = e->type->elevator_attrs; |
3d1ab40f4 [PATCH] elevator_... |
796 |
if (attr) { |
e572ec7e4 [PATCH] fix rmmod... |
797 798 |
while (attr->attr.name) { if (sysfs_create_file(&e->kobj, &attr->attr)) |
3d1ab40f4 [PATCH] elevator_... |
799 |
break; |
e572ec7e4 [PATCH] fix rmmod... |
800 |
attr++; |
3d1ab40f4 [PATCH] elevator_... |
801 802 803 |
} } kobject_uevent(&e->kobj, KOBJ_ADD); |
430c62fb2 elevator: fix oop... |
804 |
e->registered = 1; |
bd166ef18 blk-mq-sched: add... |
805 |
if (!e->uses_mq && e->type->ops.sq.elevator_registered_fn) |
c51ca6cf5 block: move exist... |
806 |
e->type->ops.sq.elevator_registered_fn(q); |
3d1ab40f4 [PATCH] elevator_... |
807 808 |
} return error; |
1da177e4c Linux-2.6.12-rc2 |
809 |
} |
f8fc877d3 block: reorder el... |
810 |
EXPORT_SYMBOL(elv_register_queue); |
bc1c11697 [PATCH] elevator ... |
811 |
|
1da177e4c Linux-2.6.12-rc2 |
812 813 |
void elv_unregister_queue(struct request_queue *q) { |
f8fc877d3 block: reorder el... |
814 815 816 817 818 819 |
if (q) { struct elevator_queue *e = q->elevator; kobject_uevent(&e->kobj, KOBJ_REMOVE); kobject_del(&e->kobj); e->registered = 0; |
8330cdb0f block: Make write... |
820 821 |
/* Re-enable throttling in case elevator disabled it */ wbt_enable_default(q); |
f8fc877d3 block: reorder el... |
822 |
} |
1da177e4c Linux-2.6.12-rc2 |
823 |
} |
01effb0dc block: allow init... |
824 |
EXPORT_SYMBOL(elv_unregister_queue); |
1da177e4c Linux-2.6.12-rc2 |
825 |
|
e567bf711 Revert "block: ad... |
826 |
int elv_register(struct elevator_type *e) |
1da177e4c Linux-2.6.12-rc2 |
827 |
{ |
1ffb96c58 make elv_register... |
828 |
char *def = ""; |
2a12dcd71 [PATCH] elevator:... |
829 |
|
3d3c2379f block, cfq: move ... |
830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 |
/* create icq_cache if requested */ if (e->icq_size) { if (WARN_ON(e->icq_size < sizeof(struct io_cq)) || WARN_ON(e->icq_align < __alignof__(struct io_cq))) return -EINVAL; snprintf(e->icq_cache_name, sizeof(e->icq_cache_name), "%s_io_cq", e->elevator_name); e->icq_cache = kmem_cache_create(e->icq_cache_name, e->icq_size, e->icq_align, 0, NULL); if (!e->icq_cache) return -ENOMEM; } /* register, don't allow duplicate names */ |
2a12dcd71 [PATCH] elevator:... |
845 |
spin_lock(&elv_list_lock); |
3d3c2379f block, cfq: move ... |
846 847 848 849 850 851 |
if (elevator_find(e->elevator_name)) { spin_unlock(&elv_list_lock); if (e->icq_cache) kmem_cache_destroy(e->icq_cache); return -EBUSY; } |
1da177e4c Linux-2.6.12-rc2 |
852 |
list_add_tail(&e->list, &elv_list); |
2a12dcd71 [PATCH] elevator:... |
853 |
spin_unlock(&elv_list_lock); |
1da177e4c Linux-2.6.12-rc2 |
854 |
|
3d3c2379f block, cfq: move ... |
855 |
/* print pretty message */ |
5f0039764 [BLOCK] elevator:... |
856 857 858 |
if (!strcmp(e->elevator_name, chosen_elevator) || (!*chosen_elevator && !strcmp(e->elevator_name, CONFIG_DEFAULT_IOSCHED))) |
1ffb96c58 make elv_register... |
859 |
def = " (default)"; |
4eb166d98 block: make eleva... |
860 861 862 |
printk(KERN_INFO "io scheduler %s registered%s ", e->elevator_name, def); |
3d3c2379f block, cfq: move ... |
863 |
return 0; |
1da177e4c Linux-2.6.12-rc2 |
864 865 866 867 868 |
} EXPORT_SYMBOL_GPL(elv_register); void elv_unregister(struct elevator_type *e) { |
3d3c2379f block, cfq: move ... |
869 |
/* unregister */ |
2a12dcd71 [PATCH] elevator:... |
870 |
spin_lock(&elv_list_lock); |
1da177e4c Linux-2.6.12-rc2 |
871 |
list_del_init(&e->list); |
2a12dcd71 [PATCH] elevator:... |
872 |
spin_unlock(&elv_list_lock); |
3d3c2379f block, cfq: move ... |
873 874 875 876 877 878 879 880 881 882 |
/* * Destroy icq_cache if it exists. icq's are RCU managed. Make * sure all RCU operations are complete before proceeding. */ if (e->icq_cache) { rcu_barrier(); kmem_cache_destroy(e->icq_cache); e->icq_cache = NULL; } |
1da177e4c Linux-2.6.12-rc2 |
883 884 |
} EXPORT_SYMBOL_GPL(elv_unregister); |
54d5329d4 blk-mq-sched: fix... |
885 886 887 888 889 890 |
static int elevator_switch_mq(struct request_queue *q, struct elevator_type *new_e) { int ret; blk_mq_freeze_queue(q); |
54d5329d4 blk-mq-sched: fix... |
891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 |
if (q->elevator) { if (q->elevator->registered) elv_unregister_queue(q); ioc_clear_queue(q); elevator_exit(q, q->elevator); } ret = blk_mq_init_sched(q, new_e); if (ret) goto out; if (new_e) { ret = elv_register_queue(q); if (ret) { elevator_exit(q, q->elevator); goto out; } } if (new_e) blk_add_trace_msg(q, "elv switch: %s", new_e->elevator_name); else blk_add_trace_msg(q, "elv switch: none"); out: blk_mq_unfreeze_queue(q); |
54d5329d4 blk-mq-sched: fix... |
918 |
return ret; |
54d5329d4 blk-mq-sched: fix... |
919 |
} |
1da177e4c Linux-2.6.12-rc2 |
920 921 922 923 |
/* * switch to new_e io scheduler. be careful not to introduce deadlocks - * we don't free the old io scheduler, before we have allocated what we * need for the new one. this way we have a chance of going back to the old |
cb98fc8bb [BLOCK] Reimpleme... |
924 |
* one, if the new one fails init for some reason. |
1da177e4c Linux-2.6.12-rc2 |
925 |
*/ |
165125e1e [BLOCK] Get rid o... |
926 |
static int elevator_switch(struct request_queue *q, struct elevator_type *new_e) |
1da177e4c Linux-2.6.12-rc2 |
927 |
{ |
5a5bafdc3 elevator: clear a... |
928 |
struct elevator_queue *old = q->elevator; |
bd166ef18 blk-mq-sched: add... |
929 |
bool old_registered = false; |
e8989fae3 blkcg: unify blkg... |
930 |
int err; |
1da177e4c Linux-2.6.12-rc2 |
931 |
|
54d5329d4 blk-mq-sched: fix... |
932 933 |
if (q->mq_ops) return elevator_switch_mq(q, new_e); |
bd166ef18 blk-mq-sched: add... |
934 |
|
5a5bafdc3 elevator: clear a... |
935 936 937 938 939 940 941 |
/* * Turn on BYPASS and drain all requests w/ elevator private data. * Block layer doesn't call into a quiesced elevator - all requests * are directly put on the dispatch list without elevator data * using INSERT_BACK. All requests have SOFTBARRIER set and no * merge happens either. */ |
bd166ef18 blk-mq-sched: add... |
942 943 |
if (old) { old_registered = old->registered; |
54d5329d4 blk-mq-sched: fix... |
944 |
blk_queue_bypass_start(q); |
1da177e4c Linux-2.6.12-rc2 |
945 |
|
bd166ef18 blk-mq-sched: add... |
946 947 948 |
/* unregister and clear all auxiliary data of the old elevator */ if (old_registered) elv_unregister_queue(q); |
bd166ef18 blk-mq-sched: add... |
949 |
ioc_clear_queue(q); |
bd166ef18 blk-mq-sched: add... |
950 |
} |
f8fc877d3 block: reorder el... |
951 |
|
5a5bafdc3 elevator: clear a... |
952 |
/* allocate, init and register new elevator */ |
54d5329d4 blk-mq-sched: fix... |
953 |
err = new_e->ops.sq.elevator_init_fn(q, new_e); |
6917ff0b5 blk-mq-sched: ref... |
954 955 |
if (err) goto fail_init; |
5a5bafdc3 elevator: clear a... |
956 |
|
54d5329d4 blk-mq-sched: fix... |
957 958 959 |
err = elv_register_queue(q); if (err) goto fail_register; |
5a5bafdc3 elevator: clear a... |
960 961 |
/* done, kill the old one and finish */ |
bd166ef18 blk-mq-sched: add... |
962 |
if (old) { |
54d5329d4 blk-mq-sched: fix... |
963 964 |
elevator_exit(q, old); blk_queue_bypass_end(q); |
bd166ef18 blk-mq-sched: add... |
965 |
} |
54d5329d4 blk-mq-sched: fix... |
966 |
blk_add_trace_msg(q, "elv switch: %s", new_e->elevator_name); |
4722dc52a Added in elevator... |
967 |
|
5dd531a03 block: add functi... |
968 |
return 0; |
1da177e4c Linux-2.6.12-rc2 |
969 970 |
fail_register: |
54d5329d4 blk-mq-sched: fix... |
971 |
elevator_exit(q, q->elevator); |
5a5bafdc3 elevator: clear a... |
972 973 |
fail_init: /* switch failed, restore and re-register old elevator */ |
bd166ef18 blk-mq-sched: add... |
974 975 976 |
if (old) { q->elevator = old; elv_register_queue(q); |
54d5329d4 blk-mq-sched: fix... |
977 |
blk_queue_bypass_end(q); |
bd166ef18 blk-mq-sched: add... |
978 |
} |
75ad23bc0 block: make queue... |
979 |
|
5dd531a03 block: add functi... |
980 |
return err; |
1da177e4c Linux-2.6.12-rc2 |
981 |
} |
5dd531a03 block: add functi... |
982 983 984 |
/* * Switch this queue to the given IO scheduler. */ |
7c8a3679e elevator: acquire... |
985 |
static int __elevator_change(struct request_queue *q, const char *name) |
1da177e4c Linux-2.6.12-rc2 |
986 987 988 |
{ char elevator_name[ELV_NAME_MAX]; struct elevator_type *e; |
e9a823fb3 block: fix warnin... |
989 990 991 |
/* Make sure queue is not in the middle of being removed */ if (!test_bit(QUEUE_FLAG_REGISTERED, &q->queue_flags)) return -ENOENT; |
bd166ef18 blk-mq-sched: add... |
992 993 994 995 996 |
/* * Special case for mq, turn off scheduling */ if (q->mq_ops && !strncmp(name, "none", 4)) return elevator_switch(q, NULL); |
cd43e26f0 block: Expose sta... |
997 |
|
ee2e992cc block: simplify s... |
998 |
strlcpy(elevator_name, name, sizeof(elevator_name)); |
21c3c5d28 block: don't requ... |
999 |
e = elevator_get(strstrip(elevator_name), true); |
340ff3216 elevator: remove ... |
1000 |
if (!e) |
1da177e4c Linux-2.6.12-rc2 |
1001 |
return -EINVAL; |
1da177e4c Linux-2.6.12-rc2 |
1002 |
|
bd166ef18 blk-mq-sched: add... |
1003 1004 |
if (q->elevator && !strcmp(elevator_name, q->elevator->type->elevator_name)) { |
2ca7d93bb [PATCH] block cle... |
1005 |
elevator_put(e); |
5dd531a03 block: add functi... |
1006 |
return 0; |
2ca7d93bb [PATCH] block cle... |
1007 |
} |
1da177e4c Linux-2.6.12-rc2 |
1008 |
|
bd166ef18 blk-mq-sched: add... |
1009 1010 1011 1012 1013 1014 1015 1016 |
if (!e->uses_mq && q->mq_ops) { elevator_put(e); return -EINVAL; } if (e->uses_mq && !q->mq_ops) { elevator_put(e); return -EINVAL; } |
5dd531a03 block: add functi... |
1017 1018 |
return elevator_switch(q, e); } |
7c8a3679e elevator: acquire... |
1019 |
|
3a5088c8c block: respect BL... |
1020 1021 1022 1023 1024 1025 1026 |
static inline bool elv_support_iosched(struct request_queue *q) { if (q->mq_ops && q->tag_set && (q->tag_set->flags & BLK_MQ_F_NO_SCHED)) return false; return true; } |
5dd531a03 block: add functi... |
1027 1028 1029 1030 |
ssize_t elv_iosched_store(struct request_queue *q, const char *name, size_t count) { int ret; |
3a5088c8c block: respect BL... |
1031 |
if (!(q->mq_ops || q->request_fn) || !elv_support_iosched(q)) |
5dd531a03 block: add functi... |
1032 |
return count; |
7c8a3679e elevator: acquire... |
1033 |
ret = __elevator_change(q, name); |
5dd531a03 block: add functi... |
1034 1035 |
if (!ret) return count; |
5dd531a03 block: add functi... |
1036 |
return ret; |
1da177e4c Linux-2.6.12-rc2 |
1037 |
} |
165125e1e [BLOCK] Get rid o... |
1038 |
ssize_t elv_iosched_show(struct request_queue *q, char *name) |
1da177e4c Linux-2.6.12-rc2 |
1039 |
{ |
b374d18a4 block: get rid of... |
1040 |
struct elevator_queue *e = q->elevator; |
bd166ef18 blk-mq-sched: add... |
1041 |
struct elevator_type *elv = NULL; |
70cee26e0 Use list_for_each... |
1042 |
struct elevator_type *__e; |
1da177e4c Linux-2.6.12-rc2 |
1043 |
int len = 0; |
bd166ef18 blk-mq-sched: add... |
1044 |
if (!blk_queue_stackable(q)) |
cd43e26f0 block: Expose sta... |
1045 1046 |
return sprintf(name, "none "); |
bd166ef18 blk-mq-sched: add... |
1047 1048 1049 1050 |
if (!q->elevator) len += sprintf(name+len, "[none] "); else elv = e->type; |
cd43e26f0 block: Expose sta... |
1051 |
|
2a12dcd71 [PATCH] elevator:... |
1052 |
spin_lock(&elv_list_lock); |
70cee26e0 Use list_for_each... |
1053 |
list_for_each_entry(__e, &elv_list, list) { |
bd166ef18 blk-mq-sched: add... |
1054 |
if (elv && !strcmp(elv->elevator_name, __e->elevator_name)) { |
1da177e4c Linux-2.6.12-rc2 |
1055 |
len += sprintf(name+len, "[%s] ", elv->elevator_name); |
bd166ef18 blk-mq-sched: add... |
1056 1057 |
continue; } |
3a5088c8c block: respect BL... |
1058 |
if (__e->uses_mq && q->mq_ops && elv_support_iosched(q)) |
bd166ef18 blk-mq-sched: add... |
1059 1060 |
len += sprintf(name+len, "%s ", __e->elevator_name); else if (!__e->uses_mq && !q->mq_ops) |
1da177e4c Linux-2.6.12-rc2 |
1061 1062 |
len += sprintf(name+len, "%s ", __e->elevator_name); } |
2a12dcd71 [PATCH] elevator:... |
1063 |
spin_unlock(&elv_list_lock); |
1da177e4c Linux-2.6.12-rc2 |
1064 |
|
bd166ef18 blk-mq-sched: add... |
1065 1066 |
if (q->mq_ops && q->elevator) len += sprintf(name+len, "none"); |
1da177e4c Linux-2.6.12-rc2 |
1067 1068 1069 1070 |
len += sprintf(len+name, " "); return len; } |
165125e1e [BLOCK] Get rid o... |
1071 1072 |
struct request *elv_rb_former_request(struct request_queue *q, struct request *rq) |
2e662b65f [PATCH] elevator:... |
1073 1074 1075 1076 1077 1078 1079 1080 |
{ struct rb_node *rbprev = rb_prev(&rq->rb_node); if (rbprev) return rb_entry_rq(rbprev); return NULL; } |
2e662b65f [PATCH] elevator:... |
1081 |
EXPORT_SYMBOL(elv_rb_former_request); |
165125e1e [BLOCK] Get rid o... |
1082 1083 |
struct request *elv_rb_latter_request(struct request_queue *q, struct request *rq) |
2e662b65f [PATCH] elevator:... |
1084 1085 1086 1087 1088 1089 1090 1091 |
{ struct rb_node *rbnext = rb_next(&rq->rb_node); if (rbnext) return rb_entry_rq(rbnext); return NULL; } |
2e662b65f [PATCH] elevator:... |
1092 |
EXPORT_SYMBOL(elv_rb_latter_request); |