From 40aabb67464d5aad9ca3d2a5fedee56e2ff45aa0 Mon Sep 17 00:00:00 2001 From: Omar Sandoval Date: Sat, 17 Sep 2016 01:28:23 -0700 Subject: sbitmap: push per-cpu last_tag into sbitmap_queue Allocating your own per-cpu allocation hint separately makes for an awkward API. Instead, allocate the per-cpu hint as part of the struct sbitmap_queue. There's no point for a struct sbitmap_queue without the cache, but you can still use a bare struct sbitmap. Signed-off-by: Omar Sandoval Signed-off-by: Jens Axboe --- block/blk-mq-tag.c | 53 +++++++++++++++++------------------------------------ 1 file changed, 17 insertions(+), 36 deletions(-) (limited to 'block/blk-mq-tag.c') diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c index 2cbdecd594e9..c9a22dbbbda1 100644 --- a/block/blk-mq-tag.c +++ b/block/blk-mq-tag.c @@ -94,39 +94,21 @@ static inline bool hctx_may_queue(struct blk_mq_hw_ctx *hctx, #define BT_ALLOC_RR(tags) (tags->alloc_policy == BLK_TAG_ALLOC_RR) static int __bt_get(struct blk_mq_hw_ctx *hctx, struct sbitmap_queue *bt, - unsigned int *tag_cache, struct blk_mq_tags *tags) + struct blk_mq_tags *tags) { - unsigned int last_tag; - int tag; - if (!hctx_may_queue(hctx, bt)) return -1; - - last_tag = *tag_cache; - tag = sbitmap_get(&bt->sb, last_tag, BT_ALLOC_RR(tags)); - - if (tag == -1) { - *tag_cache = 0; - } else if (tag == last_tag || unlikely(BT_ALLOC_RR(tags))) { - last_tag = tag + 1; - if (last_tag >= bt->sb.depth - 1) - last_tag = 0; - *tag_cache = last_tag; - } - - return tag; + return __sbitmap_queue_get(bt, BT_ALLOC_RR(tags)); } -static int bt_get(struct blk_mq_alloc_data *data, - struct sbitmap_queue *bt, - struct blk_mq_hw_ctx *hctx, - unsigned int *last_tag, struct blk_mq_tags *tags) +static int bt_get(struct blk_mq_alloc_data *data, struct sbitmap_queue *bt, + struct blk_mq_hw_ctx *hctx, struct blk_mq_tags *tags) { struct sbq_wait_state *ws; DEFINE_WAIT(wait); int tag; - tag = __bt_get(hctx, bt, last_tag, tags); + tag = __bt_get(hctx, bt, tags); if (tag != -1) return tag; @@ -137,7 +119,7 @@ static int bt_get(struct blk_mq_alloc_data *data, do { prepare_to_wait(&ws->wait, &wait, TASK_UNINTERRUPTIBLE); - tag = __bt_get(hctx, bt, last_tag, tags); + tag = __bt_get(hctx, bt, tags); if (tag != -1) break; @@ -154,7 +136,7 @@ static int bt_get(struct blk_mq_alloc_data *data, * Retry tag allocation after running the hardware queue, * as running the queue may also have found completions. */ - tag = __bt_get(hctx, bt, last_tag, tags); + tag = __bt_get(hctx, bt, tags); if (tag != -1) break; @@ -168,7 +150,6 @@ static int bt_get(struct blk_mq_alloc_data *data, if (data->flags & BLK_MQ_REQ_RESERVED) { bt = &data->hctx->tags->breserved_tags; } else { - last_tag = &data->ctx->last_tag; hctx = data->hctx; bt = &hctx->tags->bitmap_tags; } @@ -185,7 +166,7 @@ static unsigned int __blk_mq_get_tag(struct blk_mq_alloc_data *data) int tag; tag = bt_get(data, &data->hctx->tags->bitmap_tags, data->hctx, - &data->ctx->last_tag, data->hctx->tags); + data->hctx->tags); if (tag >= 0) return tag + data->hctx->tags->nr_reserved_tags; @@ -194,15 +175,15 @@ static unsigned int __blk_mq_get_tag(struct blk_mq_alloc_data *data) static unsigned int __blk_mq_get_reserved_tag(struct blk_mq_alloc_data *data) { - int tag, zero = 0; + int tag; if (unlikely(!data->hctx->tags->nr_reserved_tags)) { WARN_ON_ONCE(1); return BLK_MQ_TAG_FAIL; } - tag = bt_get(data, &data->hctx->tags->breserved_tags, NULL, &zero, - data->hctx->tags); + tag = bt_get(data, &data->hctx->tags->breserved_tags, NULL, + data->hctx->tags); if (tag < 0) return BLK_MQ_TAG_FAIL; @@ -216,8 +197,8 @@ unsigned int blk_mq_get_tag(struct blk_mq_alloc_data *data) return __blk_mq_get_tag(data); } -void blk_mq_put_tag(struct blk_mq_hw_ctx *hctx, unsigned int tag, - unsigned int *last_tag) +void blk_mq_put_tag(struct blk_mq_hw_ctx *hctx, struct blk_mq_ctx *ctx, + unsigned int tag) { struct blk_mq_tags *tags = hctx->tags; @@ -225,12 +206,12 @@ void blk_mq_put_tag(struct blk_mq_hw_ctx *hctx, unsigned int tag, const int real_tag = tag - tags->nr_reserved_tags; BUG_ON(real_tag >= tags->nr_tags); - sbitmap_queue_clear(&tags->bitmap_tags, real_tag); - if (likely(tags->alloc_policy == BLK_TAG_ALLOC_FIFO)) - *last_tag = real_tag; + sbitmap_queue_clear(&tags->bitmap_tags, real_tag, + BT_ALLOC_RR(tags), ctx->cpu); } else { BUG_ON(tag >= tags->nr_reserved_tags); - sbitmap_queue_clear(&tags->breserved_tags, tag); + sbitmap_queue_clear(&tags->breserved_tags, tag, + BT_ALLOC_RR(tags), ctx->cpu); } } -- cgit v1.2.3