Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit a73f730d authored by Tejun Heo's avatar Tejun Heo Committed by Jens Axboe
Browse files

block, cfq: move cfqd->cic_index to q->id 



cfq allocates per-queue id using ida and uses it to index cic radix
tree from io_context.  Move it to q->id and allocate on queue init and
free on queue release.  This simplifies cfq a bit and will allow for
further improvements of io context life-cycle management.

This patch doesn't introduce any functional difference.

Signed-off-by: default avatarTejun Heo <tj@kernel.org>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 8ba61435

block/blk-core.c

+16 −8
Original line number Diff line number Diff line
@@ -39,6 +39,8 @@ EXPORT_TRACEPOINT_SYMBOL_GPL(block_bio_remap); 
EXPORT_TRACEPOINT_SYMBOL_GPL(block_rq_remap);

EXPORT_TRACEPOINT_SYMBOL_GPL(block_bio_complete);



DEFINE_IDA(blk_queue_ida);



/*

 * For the allocated request tables

 */
@@ -474,6 +476,10 @@ struct request_queue *blk_alloc_queue_node(gfp_t gfp_mask, int node_id) 
	if (!q)

		return NULL;



	q->id = ida_simple_get(&blk_queue_ida, 0, 0, GFP_KERNEL);

	if (q->id < 0)

		goto fail_q;



	q->backing_dev_info.ra_pages =

			(VM_MAX_READAHEAD * 1024) / PAGE_CACHE_SIZE;

	q->backing_dev_info.state = 0;
@@ -481,15 +487,11 @@ struct request_queue *blk_alloc_queue_node(gfp_t gfp_mask, int node_id) 
	q->backing_dev_info.name = "block";



	err = bdi_init(&q->backing_dev_info);

	if (err) {

		kmem_cache_free(blk_requestq_cachep, q);

		return NULL;

	}

	if (err)

		goto fail_id;



	if (blk_throtl_init(q)) {

		kmem_cache_free(blk_requestq_cachep, q);

		return NULL;

	}

	if (blk_throtl_init(q))

		goto fail_id;



	setup_timer(&q->backing_dev_info.laptop_mode_wb_timer,

		    laptop_mode_timer_fn, (unsigned long) q);
@@ -512,6 +514,12 @@ struct request_queue *blk_alloc_queue_node(gfp_t gfp_mask, int node_id) 
	q->queue_lock = &q->__queue_lock;



	return q;



fail_id:

	ida_simple_remove(&blk_queue_ida, q->id);

fail_q:

	kmem_cache_free(blk_requestq_cachep, q);

	return NULL;

}

EXPORT_SYMBOL(blk_alloc_queue_node);

block/blk-sysfs.c

+2 −0
Original line number Diff line number Diff line
@@ -494,6 +494,8 @@ static void blk_release_queue(struct kobject *kobj) 
	blk_trace_shutdown(q);



	bdi_destroy(&q->backing_dev_info);



	ida_simple_remove(&blk_queue_ida, q->id);

	kmem_cache_free(blk_requestq_cachep, q);

}

block/blk.h

+3 −0
Original line number Diff line number Diff line 
#ifndef BLK_INTERNAL_H

#define BLK_INTERNAL_H



#include <linux/idr.h>



/* Amount of time in which a process may batch requests */

#define BLK_BATCH_TIME	(HZ/50UL)
@@ -9,6 +11,7 @@ 


extern struct kmem_cache *blk_requestq_cachep;

extern struct kobj_type blk_queue_ktype;

extern struct ida blk_queue_ida;



void init_request_from_bio(struct request *req, struct bio *bio);

void blk_rq_bio_prep(struct request_queue *q, struct request *rq,

block/cfq-iosched.c

+5 −47
Original line number Diff line number Diff line
@@ -65,9 +65,6 @@ static DEFINE_PER_CPU(unsigned long, cfq_ioc_count); 
static struct completion *ioc_gone;

static DEFINE_SPINLOCK(ioc_gone_lock);



static DEFINE_SPINLOCK(cic_index_lock);

static DEFINE_IDA(cic_index_ida);



#define CFQ_PRIO_LISTS		IOPRIO_BE_NR

#define cfq_class_idle(cfqq)	((cfqq)->ioprio_class == IOPRIO_CLASS_IDLE)

#define cfq_class_rt(cfqq)	((cfqq)->ioprio_class == IOPRIO_CLASS_RT)
@@ -290,7 +287,6 @@ struct cfq_data { 
	unsigned int cfq_group_idle;

	unsigned int cfq_latency;



	unsigned int cic_index;

	struct list_head cic_list;



	/*
@@ -484,7 +480,7 @@ static inline void cic_set_cfqq(struct cfq_io_context *cic, 


static inline void *cfqd_dead_key(struct cfq_data *cfqd)

{

	return (void *)(cfqd->cic_index << CIC_DEAD_INDEX_SHIFT | CIC_DEAD_KEY);

	return (void *)(cfqd->queue->id << CIC_DEAD_INDEX_SHIFT | CIC_DEAD_KEY);

}



static inline struct cfq_data *cic_to_cfqd(struct cfq_io_context *cic)
@@ -3105,7 +3101,7 @@ cfq_drop_dead_cic(struct cfq_data *cfqd, struct io_context *ioc, 
	BUG_ON(rcu_dereference_check(ioc->ioc_data,

		lockdep_is_held(&ioc->lock)) == cic);



	radix_tree_delete(&ioc->radix_root, cfqd->cic_index);

	radix_tree_delete(&ioc->radix_root, cfqd->queue->id);

	hlist_del_rcu(&cic->cic_list);

	spin_unlock_irqrestore(&ioc->lock, flags);
@@ -3133,7 +3129,7 @@ cfq_cic_lookup(struct cfq_data *cfqd, struct io_context *ioc) 
	}



	do {

		cic = radix_tree_lookup(&ioc->radix_root, cfqd->cic_index);

		cic = radix_tree_lookup(&ioc->radix_root, cfqd->queue->id);

		rcu_read_unlock();

		if (!cic)

			break;
@@ -3169,8 +3165,7 @@ static int cfq_cic_link(struct cfq_data *cfqd, struct io_context *ioc, 
		cic->key = cfqd;



		spin_lock_irqsave(&ioc->lock, flags);

		ret = radix_tree_insert(&ioc->radix_root,

						cfqd->cic_index, cic);

		ret = radix_tree_insert(&ioc->radix_root, cfqd->queue->id, cic);

		if (!ret)

			hlist_add_head_rcu(&cic->cic_list, &ioc->cic_list);

		spin_unlock_irqrestore(&ioc->lock, flags);
@@ -3944,10 +3939,6 @@ static void cfq_exit_queue(struct elevator_queue *e) 


	cfq_shutdown_timer_wq(cfqd);



	spin_lock(&cic_index_lock);

	ida_remove(&cic_index_ida, cfqd->cic_index);

	spin_unlock(&cic_index_lock);



	/*

	 * Wait for cfqg->blkg->key accessors to exit their grace periods.

	 * Do this wait only if there are other unlinked groups out
@@ -3969,24 +3960,6 @@ static void cfq_exit_queue(struct elevator_queue *e) 
	kfree(cfqd);

}



static int cfq_alloc_cic_index(void)

{

	int index, error;



	do {

		if (!ida_pre_get(&cic_index_ida, GFP_KERNEL))

			return -ENOMEM;



		spin_lock(&cic_index_lock);

		error = ida_get_new(&cic_index_ida, &index);

		spin_unlock(&cic_index_lock);

		if (error && error != -EAGAIN)

			return error;

	} while (error);



	return index;

}



static void *cfq_init_queue(struct request_queue *q)

{

	struct cfq_data *cfqd;
@@ -3994,23 +3967,9 @@ static void *cfq_init_queue(struct request_queue *q) 
	struct cfq_group *cfqg;

	struct cfq_rb_root *st;



	i = cfq_alloc_cic_index();

	if (i < 0)

		return NULL;



	cfqd = kmalloc_node(sizeof(*cfqd), GFP_KERNEL | __GFP_ZERO, q->node);

	if (!cfqd) {

		spin_lock(&cic_index_lock);

		ida_remove(&cic_index_ida, i);

		spin_unlock(&cic_index_lock);

	if (!cfqd)

		return NULL;

	}



	/*

	 * Don't need take queue_lock in the routine, since we are

	 * initializing the ioscheduler, and nobody is using cfqd

	 */

	cfqd->cic_index = i;



	/* Init root service tree */

	cfqd->grp_service_tree = CFQ_RB_ROOT;
@@ -4294,7 +4253,6 @@ static void __exit cfq_exit(void) 
	 */

	if (elv_ioc_count_read(cfq_ioc_count))

		wait_for_completion(&all_gone);

	ida_destroy(&cic_index_ida);

	cfq_slab_kill();

}

include/linux/blkdev.h

+6 −0
Original line number Diff line number Diff line
@@ -310,6 +310,12 @@ struct request_queue { 
	 */

	unsigned long		queue_flags;



	/*

	 * ida allocated id for this queue.  Used to index queues from

	 * ioctx.

	 */

	int			id;



	/*

	 * queue needs bounce pages for pages above this limit

	 */