linux-master/block/blk-mq-tag.c

4  * fairer distribution of tags between multiple submitters when a shared tag map
18  * Recalculate wakeup batch when tag is shared by hctx.
34  * We need to do this before try to allocate driver tag, then even if fail
35  * to get tag when first time, the other shared-tag users could reserve
140 	int tag;
154 	tag = __blk_mq_get_tag(data, bt);
155 	if (tag != BLK_MQ_NO_TAG)
173 		 * Retry tag allocation after running the hardware queue,
176 		tag = __blk_mq_get_tag(data, bt);
177 		if (tag != BLK_MQ_NO_TAG)
182 		tag = __blk_mq_get_tag(data, bt);
183 		if (tag != BLK_MQ_NO_TAG)
219 		blk_mq_put_tag(tags, data->ctx, tag + tag_offset);
222 	return tag + tag_offset;
226 		    unsigned int tag)
228 	if (!blk_mq_tag_is_reserved(tags, tag)) {
229 		const int real_tag = tag - tags->nr_reserved_tags;
234 		sbitmap_queue_clear(&tags->breserved_tags, tag, ctx->cpu);
260 	if (!rq || rq->tag != bitnr || !req_ref_inc_not_zero(rq))
304  *		associated with @hctx that has been assigned a driver tag.
369  * bt_tags_for_each - iterate over the requests in a tag map
406  * blk_mq_all_tag_iter - iterate over all requests in a tag map
415  * Caller has to pass the tag map from which requests are allocated.
424  * blk_mq_tagset_busy_iter - iterate over all started requests in a tag set
483  * blk_mq_queue_tag_busy_iter - iterate over all requests with a driver tag
493  * called for all requests on all queues that share that tag set and not only
573 		pr_err("blk-mq: tag depth too large\n");
667  * blk_mq_unique_tag() - return a tag that is unique queue-wide
668  * @rq: request for which to compute a unique tag
670  * The tag field in struct request is unique per hardware queue but not over
671  * all hardware queues. Hence this function that returns a tag with the
672  * hardware context index in the upper bits and the per hardware queue tag in
681 		(rq->tag & BLK_MQ_UNIQUE_TAG_MASK);