return;
wait_cnt = atomic_dec_return(&bs->wait_cnt);
+ if (unlikely(wait_cnt < 0))
+ wait_cnt = atomic_inc_return(&bs->wait_cnt);
if (wait_cnt == 0) {
-wake:
atomic_add(bt->wake_cnt, &bs->wait_cnt);
bt_index_atomic_inc(&bt->wake_index);
wake_up(&bs->wait);
- } else if (wait_cnt < 0) {
- wait_cnt = atomic_inc_return(&bs->wait_cnt);
- if (!wait_cnt)
- goto wake;
}
}
__blk_mq_put_reserved_tag(tags, tag);
}
-static void bt_for_each_free(struct blk_mq_bitmap_tags *bt,
- unsigned long *free_map, unsigned int off)
+static void bt_for_each(struct blk_mq_hw_ctx *hctx,
+ struct blk_mq_bitmap_tags *bt, unsigned int off,
+ busy_iter_fn *fn, void *data, bool reserved)
{
- int i;
+ struct request *rq;
+ int bit, i;
for (i = 0; i < bt->map_nr; i++) {
struct blk_align_bitmap *bm = &bt->map[i];
- int bit = 0;
- do {
- bit = find_next_zero_bit(&bm->word, bm->depth, bit);
- if (bit >= bm->depth)
- break;
-
- __set_bit(bit + off, free_map);
- bit++;
- } while (1);
+ for (bit = find_first_bit(&bm->word, bm->depth);
+ bit < bm->depth;
+ bit = find_next_bit(&bm->word, bm->depth, bit + 1)) {
+ rq = blk_mq_tag_to_rq(hctx->tags, off + bit);
+ if (rq->q == hctx->queue)
+ fn(hctx, rq, data, reserved);
+ }
off += (1 << bt->bits_per_word);
}
}
-void blk_mq_tag_busy_iter(struct blk_mq_tags *tags,
- void (*fn)(void *, unsigned long *), void *data)
+void blk_mq_tag_busy_iter(struct blk_mq_hw_ctx *hctx, busy_iter_fn *fn,
+ void *priv)
{
- unsigned long *tag_map;
- size_t map_size;
-
- map_size = ALIGN(tags->nr_tags, BITS_PER_LONG) / BITS_PER_LONG;
- tag_map = kzalloc(map_size * sizeof(unsigned long), GFP_ATOMIC);
- if (!tag_map)
- return;
+ struct blk_mq_tags *tags = hctx->tags;
- bt_for_each_free(&tags->bitmap_tags, tag_map, tags->nr_reserved_tags);
if (tags->nr_reserved_tags)
- bt_for_each_free(&tags->breserved_tags, tag_map, 0);
-
- fn(data, tag_map);
- kfree(tag_map);
+ bt_for_each(hctx, &tags->breserved_tags, 0, fn, priv, true);
+ bt_for_each(hctx, &tags->bitmap_tags, tags->nr_reserved_tags, fn, priv,
+ false);
}
EXPORT_SYMBOL(blk_mq_tag_busy_iter);
}
bt->wake_cnt = BT_WAIT_BATCH;
- if (bt->wake_cnt > depth / 4)
- bt->wake_cnt = max(1U, depth / 4);
+ if (bt->wake_cnt > depth / BT_WAIT_QUEUES)
+ bt->wake_cnt = max(1U, depth / BT_WAIT_QUEUES);
bt->depth = depth;
}
return 0;
}
+/**
+ * blk_mq_unique_tag() - return a tag that is unique queue-wide
+ * @rq: request for which to compute a unique tag
+ *
+ * The tag field in struct request is unique per hardware queue but not over
+ * all hardware queues. Hence this function that returns a tag with the
+ * hardware context index in the upper bits and the per hardware queue tag in
+ * the lower bits.
+ *
+ * Note: When called for a request that is queued on a non-multiqueue request
+ * queue, the hardware context index is set to zero.
+ */
+u32 blk_mq_unique_tag(struct request *rq)
+{
+ struct request_queue *q = rq->q;
+ struct blk_mq_hw_ctx *hctx;
+ int hwq = 0;
+
+ if (q->mq_ops) {
+ hctx = q->mq_ops->map_queue(q, rq->mq_ctx->cpu);
+ hwq = hctx->queue_num;
+ }
+
+ return (hwq << BLK_MQ_UNIQUE_TAG_BITS) |
+ (rq->tag & BLK_MQ_UNIQUE_TAG_MASK);
+}
+EXPORT_SYMBOL(blk_mq_unique_tag);
+
ssize_t blk_mq_tag_sysfs_show(struct blk_mq_tags *tags, char *page)
{
char *orig_page = page;