blk-mq: Allow requests to never expire

Some types of requests may be started that are not gauranteed to ever
complete. This adds a request flag that a driver can use so mark the
request as such.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
This commit is contained in:
Keith Busch 2015-01-07 18:55:46 -07:00 committed by Jens Axboe
parent 1885b24d23
commit 5b3f25fc34
3 changed files with 8 additions and 1 deletions

View file

@ -619,7 +619,7 @@ void blk_mq_rq_timed_out(struct request *req, bool reserved)
break;
}
}
static void blk_mq_check_expired(struct blk_mq_hw_ctx *hctx,
struct request *rq, void *priv, bool reserved)
{
@ -627,6 +627,8 @@ static void blk_mq_check_expired(struct blk_mq_hw_ctx *hctx,
if (!test_bit(REQ_ATOM_STARTED, &rq->atomic_flags))
return;
if (rq->cmd_flags & REQ_NO_TIMEOUT)
return;
if (time_after_eq(jiffies, rq->deadline)) {
if (!blk_mark_rq_complete(rq))

View file

@ -190,6 +190,9 @@ void blk_add_timer(struct request *req)
struct request_queue *q = req->q;
unsigned long expiry;
if (req->cmd_flags & REQ_NO_TIMEOUT)
return;
/* blk-mq has its own handler, so we don't need ->rq_timed_out_fn */
if (!q->mq_ops && !q->rq_timed_out_fn)
return;

View file

@ -190,6 +190,7 @@ enum rq_flag_bits {
__REQ_PM, /* runtime pm request */
__REQ_HASHED, /* on IO scheduler merge hash */
__REQ_MQ_INFLIGHT, /* track inflight for MQ */
__REQ_NO_TIMEOUT, /* requests may never expire */
__REQ_NR_BITS, /* stops here */
};
@ -243,5 +244,6 @@ enum rq_flag_bits {
#define REQ_PM (1ULL << __REQ_PM)
#define REQ_HASHED (1ULL << __REQ_HASHED)
#define REQ_MQ_INFLIGHT (1ULL << __REQ_MQ_INFLIGHT)
#define REQ_NO_TIMEOUT (1ULL << __REQ_NO_TIMEOUT)
#endif /* __LINUX_BLK_TYPES_H */