blk-mq: add support for carrying internal tag information in blk_qc_t

No functional change in this patch, just in preparation for having
two types of tags available to the block layer for a single request.

Signed-off-by: Jens Axboe <axboe@fb.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
This commit is contained in:
Jens Axboe 2017-01-12 10:04:45 -07:00
parent cc71a6f438
commit fd2d332677
2 changed files with 25 additions and 8 deletions

View File

@ -1308,6 +1308,11 @@ static struct request *blk_mq_map_request(struct request_queue *q,
return rq;
}
static blk_qc_t request_to_qc_t(struct blk_mq_hw_ctx *hctx, struct request *rq)
{
return blk_tag_to_qc_t(rq->tag, hctx->queue_num, false);
}
static void blk_mq_try_issue_directly(struct request *rq, blk_qc_t *cookie)
{
int ret;
@ -1318,7 +1323,7 @@ static void blk_mq_try_issue_directly(struct request *rq, blk_qc_t *cookie)
.list = NULL,
.last = 1
};
blk_qc_t new_cookie = blk_tag_to_qc_t(rq->tag, hctx->queue_num);
blk_qc_t new_cookie = request_to_qc_t(hctx, rq);
if (blk_mq_hctx_stopped(hctx))
goto insert;
@ -1387,7 +1392,7 @@ static blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio)
wbt_track(&rq->issue_stat, wb_acct);
cookie = blk_tag_to_qc_t(rq->tag, data.hctx->queue_num);
cookie = request_to_qc_t(data.hctx, rq);
if (unlikely(is_flush_fua)) {
blk_mq_bio_to_request(rq, bio);
@ -1496,7 +1501,7 @@ static blk_qc_t blk_sq_make_request(struct request_queue *q, struct bio *bio)
wbt_track(&rq->issue_stat, wb_acct);
cookie = blk_tag_to_qc_t(rq->tag, data.hctx->queue_num);
cookie = request_to_qc_t(data.hctx, rq);
if (unlikely(is_flush_fua)) {
blk_mq_bio_to_request(rq, bio);

View File

@ -232,22 +232,29 @@ static inline bool op_is_sync(unsigned int op)
}
typedef unsigned int blk_qc_t;
#define BLK_QC_T_NONE -1U
#define BLK_QC_T_SHIFT 16
#define BLK_QC_T_NONE -1U
#define BLK_QC_T_SHIFT 16
#define BLK_QC_T_INTERNAL (1U << 31)
static inline bool blk_qc_t_valid(blk_qc_t cookie)
{
return cookie != BLK_QC_T_NONE;
}
static inline blk_qc_t blk_tag_to_qc_t(unsigned int tag, unsigned int queue_num)
static inline blk_qc_t blk_tag_to_qc_t(unsigned int tag, unsigned int queue_num,
bool internal)
{
return tag | (queue_num << BLK_QC_T_SHIFT);
blk_qc_t ret = tag | (queue_num << BLK_QC_T_SHIFT);
if (internal)
ret |= BLK_QC_T_INTERNAL;
return ret;
}
static inline unsigned int blk_qc_t_to_queue_num(blk_qc_t cookie)
{
return cookie >> BLK_QC_T_SHIFT;
return (cookie & ~BLK_QC_T_INTERNAL) >> BLK_QC_T_SHIFT;
}
static inline unsigned int blk_qc_t_to_tag(blk_qc_t cookie)
@ -255,6 +262,11 @@ static inline unsigned int blk_qc_t_to_tag(blk_qc_t cookie)
return cookie & ((1u << BLK_QC_T_SHIFT) - 1);
}
static inline bool blk_qc_t_is_internal(blk_qc_t cookie)
{
return (cookie & BLK_QC_T_INTERNAL) != 0;
}
struct blk_issue_stat {
u64 time;
};