blk-mq: remove hybrid polling

io_uring provides the only way user space can poll completions, and that
always sets BLK_POLL_NOSLEEP. This effectively makes hybrid polling dead
code, so remove it and everything supporting it.

Hybrid polling was effectively killed off with 9650b453a3, "block:
ignore RWF_HIPRI hint for sync dio", but still potentially reachable
through io_uring until d729cf9acb, "io_uring: don't sleep when
polling for I/O", but hybrid polling probably should not have been
reachable through that async interface from the beginning.

Fixes: 9650b453a3 ("block: ignore RWF_HIPRI hint for sync dio")
Fixes: d729cf9acb ("io_uring: don't sleep when polling for I/O")
Signed-off-by: Keith Busch <kbusch@kernel.org>
Link: https://lore.kernel.org/r/20230320194926.3353144-1-kbusch@meta.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Keith Busch
2023-03-20 12:49:26 -07:00
committed by Jens Axboe
parent 4cf2c3ab2c
commit 54bdd67d0f
9 changed files with 12 additions and 299 deletions

View File

@@ -44,12 +44,6 @@ extern const struct device_type disk_type;
extern struct device_type part_type;
extern struct class block_class;
/* Must be consistent with blk_mq_poll_stats_bkt() */
#define BLK_MQ_POLL_STATS_BKTS 16
/* Doing classic polling */
#define BLK_MQ_POLL_CLASSIC -1
/*
* Maximum number of blkcg policies allowed to be registered concurrently.
* Defined here to simplify include dependency.
@@ -468,10 +462,6 @@ struct request_queue {
#endif
unsigned int rq_timeout;
int poll_nsec;
struct blk_stat_callback *poll_cb;
struct blk_rq_stat *poll_stat;
struct timer_list timeout;
struct work_struct timeout_work;
@@ -870,8 +860,6 @@ blk_status_t errno_to_blk_status(int errno);
/* only poll the hardware once, don't continue until a completion was found */
#define BLK_POLL_ONESHOT (1 << 0)
/* do not sleep to wait for the expected completion time */
#define BLK_POLL_NOSLEEP (1 << 1)
int bio_poll(struct bio *bio, struct io_comp_batch *iob, unsigned int flags);
int iocb_bio_iopoll(struct kiocb *kiocb, struct io_comp_batch *iob,
unsigned int flags);