From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Bart Van Assche To: Jens Axboe Cc: linux-block@vger.kernel.org, Christoph Hellwig , Bart Van Assche , Ming Lei , Jianchao Wang , Hannes Reinecke , Johannes Thumshirn Subject: [PATCH v9 1/8] blk-mq: Document the functions that iterate over requests Date: Wed, 19 Sep 2018 15:45:23 -0700 Message-Id: <20180919224530.222469-2-bvanassche@acm.org> In-Reply-To: <20180919224530.222469-1-bvanassche@acm.org> References: <20180919224530.222469-1-bvanassche@acm.org> MIME-Version: 1.0 List-ID: Make it easier to understand the purpose of the functions that iterate over requests by documenting their purpose. Fix three minor spelling mistakes in comments in these functions. Signed-off-by: Bart Van Assche Cc: Christoph Hellwig Cc: Ming Lei Cc: Jianchao Wang Cc: Hannes Reinecke Cc: Johannes Thumshirn --- block/blk-mq-tag.c | 30 +++++++++++++++++++++++++++--- 1 file changed, 27 insertions(+), 3 deletions(-) diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c index 94e1ed667b6e..cb5db0c3cc32 100644 --- a/block/blk-mq-tag.c +++ b/block/blk-mq-tag.c @@ -232,13 +232,19 @@ static bool bt_iter(struct sbitmap *bitmap, unsigned int bitnr, void *data) /* * We can hit rq == NULL here, because the tagging functions - * test and set the bit before assining ->rqs[]. + * test and set the bit before assigning ->rqs[]. */ if (rq && rq->q == hctx->queue) iter_data->fn(hctx, rq, iter_data->data, reserved); return true; } +/* + * Call function @fn(@hctx, rq, @data, @reserved) for each request queued on + * @hctx that has been assigned a driver tag. @reserved indicates whether @bt + * is the breserved_tags member or the bitmap_tags member of struct + * blk_mq_tags. + */ static void bt_for_each(struct blk_mq_hw_ctx *hctx, struct sbitmap_queue *bt, busy_iter_fn *fn, void *data, bool reserved) { @@ -280,6 +286,11 @@ static bool bt_tags_iter(struct sbitmap *bitmap, unsigned int bitnr, void *data) return true; } +/* + * Call function @fn(rq, @data, @reserved) for each request in @tags that has + * been started. @reserved indicates whether @bt is the breserved_tags member + * or the bitmap_tags member of struct blk_mq_tags. + */ static void bt_tags_for_each(struct blk_mq_tags *tags, struct sbitmap_queue *bt, busy_tag_iter_fn *fn, void *data, bool reserved) { @@ -294,6 +305,10 @@ static void bt_tags_for_each(struct blk_mq_tags *tags, struct sbitmap_queue *bt, sbitmap_for_each_set(&bt->sb, bt_tags_iter, &iter_data); } +/* + * Call @fn(rq, @priv, reserved) for each started request in @tags. 'reserved' + * indicates whether or not 'rq' is a reserved request. + */ static void blk_mq_all_tag_busy_iter(struct blk_mq_tags *tags, busy_tag_iter_fn *fn, void *priv) { @@ -302,6 +317,10 @@ static void blk_mq_all_tag_busy_iter(struct blk_mq_tags *tags, bt_tags_for_each(tags, &tags->bitmap_tags, fn, priv, false); } +/* + * Call @fn(rq, @priv, reserved) for each request in @tagset. 'reserved' + * indicates whether or not 'rq' is a reserved request. + */ void blk_mq_tagset_busy_iter(struct blk_mq_tag_set *tagset, busy_tag_iter_fn *fn, void *priv) { @@ -314,6 +333,11 @@ void blk_mq_tagset_busy_iter(struct blk_mq_tag_set *tagset, } EXPORT_SYMBOL(blk_mq_tagset_busy_iter); +/* + * Call @fn(rq, @priv, reserved) for each request associated with request + * queue @q or any queue it shares tags with and that has been assigned a + * driver tag. 'reserved' indicates whether or not 'rq' is a reserved request. + */ void blk_mq_queue_tag_busy_iter(struct request_queue *q, busy_iter_fn *fn, void *priv) { @@ -323,7 +347,7 @@ void blk_mq_queue_tag_busy_iter(struct request_queue *q, busy_iter_fn *fn, /* * __blk_mq_update_nr_hw_queues will update the nr_hw_queues and * queue_hw_ctx after freeze the queue. So we could use q_usage_counter - * to avoid race with it. __blk_mq_update_nr_hw_queues will users + * to avoid race with it. __blk_mq_update_nr_hw_queues will use * synchronize_rcu to ensure all of the users go out of the critical * section below and see zeroed q_usage_counter. */ @@ -337,7 +361,7 @@ void blk_mq_queue_tag_busy_iter(struct request_queue *q, busy_iter_fn *fn, struct blk_mq_tags *tags = hctx->tags; /* - * If not software queues are currently mapped to this + * If no software queues are currently mapped to this * hardware queue, there's nothing to check */ if (!blk_mq_hw_queue_mapped(hctx)) -- 2.19.0.397.gdd90340f6a-goog