From a612fddf0d8090f2877305c9168b6c1a34fb5d90 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Wed, 14 Dec 2011 00:33:41 +0100 Subject: [PATCH] block, cfq: move cfqd->icq_list to request_queue and add request->elv.icq Most of icq management is about to be moved out of cfq into blk-ioc. This patch prepares for it. * Move cfqd->icq_list to request_queue->icq_list * Make request explicitly point to icq instead of through elevator private data. ->elevator_private[3] is replaced with sub struct elv which contains icq pointer and priv[2]. cfq is updated accordingly. * Meaningless clearing of ->elevator_private[0] removed from elv_set_request(). At that point in code, the field was guaranteed to be %NULL anyway. This patch doesn't introduce any functional change. Signed-off-by: Tejun Heo Signed-off-by: Jens Axboe --- block/blk-core.c | 1 + block/cfq-iosched.c | 28 +++++++++++----------------- block/elevator.c | 2 -- include/linux/blkdev.h | 10 ++++++++-- 4 files changed, 20 insertions(+), 21 deletions(-) diff --git a/block/blk-core.c b/block/blk-core.c index 6804fdf27eff..3c26c7f48703 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -497,6 +497,7 @@ struct request_queue *blk_alloc_queue_node(gfp_t gfp_mask, int node_id) laptop_mode_timer_fn, (unsigned long) q); setup_timer(&q->timeout, blk_rq_timed_out_timer, (unsigned long) q); INIT_LIST_HEAD(&q->timeout_list); + INIT_LIST_HEAD(&q->icq_list); INIT_LIST_HEAD(&q->flush_queue[0]); INIT_LIST_HEAD(&q->flush_queue[1]); INIT_LIST_HEAD(&q->flush_data_in_flight); diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c index d2f16fcdec7f..9bc5ecc1b336 100644 --- a/block/cfq-iosched.c +++ b/block/cfq-iosched.c @@ -54,9 +54,9 @@ 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) 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]) +#define RQ_CIC(rq) icq_to_cic((rq)->elv.icq) +#define RQ_CFQQ(rq) (struct cfq_queue *) ((rq)->elv.priv[0]) +#define RQ_CFQG(rq) (struct cfq_group *) ((rq)->elv.priv[1]) static struct kmem_cache *cfq_pool; static struct kmem_cache *cfq_icq_pool; @@ -297,8 +297,6 @@ struct cfq_data { unsigned int cfq_group_idle; unsigned int cfq_latency; - struct list_head icq_list; - /* * Fallback dummy cfqq for extreme OOM conditions */ @@ -3053,7 +3051,7 @@ static int cfq_create_cic(struct cfq_data *cfqd, gfp_t gfp_mask) ret = radix_tree_insert(&ioc->icq_tree, q->id, icq); if (likely(!ret)) { hlist_add_head(&icq->ioc_node, &ioc->icq_list); - list_add(&icq->q_node, &cfqd->icq_list); + list_add(&icq->q_node, &q->icq_list); icq = NULL; } else if (ret == -EEXIST) { /* someone else already did it */ @@ -3605,12 +3603,10 @@ static void cfq_put_request(struct request *rq) put_io_context(RQ_CIC(rq)->icq.ioc, cfqq->cfqd->queue); - rq->elevator_private[0] = NULL; - rq->elevator_private[1] = NULL; - /* Put down rq reference on cfqg */ cfq_put_cfqg(RQ_CFQG(rq)); - rq->elevator_private[2] = NULL; + rq->elv.priv[0] = NULL; + rq->elv.priv[1] = NULL; cfq_put_queue(cfqq); } @@ -3696,9 +3692,9 @@ new_queue: cfqq->allocated[rw]++; cfqq->ref++; - rq->elevator_private[0] = &cic->icq; - rq->elevator_private[1] = cfqq; - rq->elevator_private[2] = cfq_ref_get_cfqg(cfqq->cfqg); + rq->elv.icq = &cic->icq; + rq->elv.priv[0] = cfqq; + rq->elv.priv[1] = cfq_ref_get_cfqg(cfqq->cfqg); spin_unlock_irq(q->queue_lock); return 0; @@ -3810,8 +3806,8 @@ 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->icq_list)) { - struct io_cq *icq = list_entry(cfqd->icq_list.next, + while (!list_empty(&q->icq_list)) { + struct io_cq *icq = list_entry(q->icq_list.next, struct io_cq, q_node); struct io_context *ioc = icq->ioc; @@ -3922,8 +3918,6 @@ 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->icq_list); - cfqd->queue = q; init_timer(&cfqd->idle_slice_timer); diff --git a/block/elevator.c b/block/elevator.c index 31ffe76aed3d..c5c6214829cb 100644 --- a/block/elevator.c +++ b/block/elevator.c @@ -745,8 +745,6 @@ int elv_set_request(struct request_queue *q, struct request *rq, gfp_t gfp_mask) if (e->type->ops.elevator_set_req_fn) return e->type->ops.elevator_set_req_fn(q, rq, gfp_mask); - - rq->elevator_private[0] = NULL; return 0; } diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 65c2f8c70089..8bca04873f53 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -111,10 +111,14 @@ struct request { * Three pointers are available for the IO schedulers, if they need * more they have to dynamically allocate it. Flush requests are * never put on the IO scheduler. So let the flush fields share - * space with the three elevator_private pointers. + * space with the elevator data. */ union { - void *elevator_private[3]; + struct { + struct io_cq *icq; + void *priv[2]; + } elv; + struct { unsigned int seq; struct list_head list; @@ -357,6 +361,8 @@ struct request_queue { struct timer_list timeout; struct list_head timeout_list; + struct list_head icq_list; + struct queue_limits limits; /* -- 2.20.1