Read/write/flush are the most common operations, optimize switch in
is_abnormal_io() for those cases. Follows same pattern established in
block perf-wip commit ("block: optimise blk_may_split for normal rw")Also, push is_abnormal_io() check and blk_queue_split() down from dm_submit_bio() to dm_split_and_process_bio() and set new 'is_abnormal_io' flag in clone_info. Optimize __split_and_process_bio and __process_abnormal_io by leveraging ci.is_abnormal_io flag. Signed-off-by: Mike Snitzer <[email protected]> --- drivers/md/dm.c | 60 +++++++++++++++++++++++++++++---------------------------- 1 file changed, 31 insertions(+), 29 deletions(-) diff --git a/drivers/md/dm.c b/drivers/md/dm.c index 3b87d151ef88..b9c30dfe0f2a 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -84,7 +84,8 @@ struct clone_info { struct dm_io *io; sector_t sector; unsigned sector_count; - bool submit_as_polled; + bool is_abnormal_io:1; + bool submit_as_polled:1; }; #define DM_TARGET_IO_BIO_OFFSET (offsetof(struct dm_target_io, clone)) @@ -1492,21 +1493,24 @@ static void __send_changing_extent_only(struct clone_info *ci, struct dm_target static bool is_abnormal_io(struct bio *bio) { - bool r = false; + unsigned int op = bio_op(bio); - switch (bio_op(bio)) { - case REQ_OP_DISCARD: - case REQ_OP_SECURE_ERASE: - case REQ_OP_WRITE_ZEROES: - r = true; - break; + if (op != REQ_OP_READ && op != REQ_OP_WRITE && op != REQ_OP_FLUSH) { + switch (op) { + case REQ_OP_DISCARD: + case REQ_OP_SECURE_ERASE: + case REQ_OP_WRITE_ZEROES: + return true; + default: + break; + } } - return r; + return false; } -static bool __process_abnormal_io(struct clone_info *ci, struct dm_target *ti, - blk_status_t *status) +static blk_status_t __process_abnormal_io(struct clone_info *ci, + struct dm_target *ti) { unsigned num_bios = 0; @@ -1520,8 +1524,6 @@ static bool __process_abnormal_io(struct clone_info *ci, struct dm_target *ti, case REQ_OP_WRITE_ZEROES: num_bios = ti->num_write_zeroes_bios; break; - default: - return false; } /* @@ -1531,12 +1533,10 @@ static bool __process_abnormal_io(struct clone_info *ci, struct dm_target *ti, * check was performed. */ if (unlikely(!num_bios)) - *status = BLK_STS_NOTSUPP; - else { - __send_changing_extent_only(ci, ti, num_bios); - *status = BLK_STS_OK; - } - return true; + return BLK_STS_NOTSUPP; + + __send_changing_extent_only(ci, ti, num_bios); + return BLK_STS_OK; } /* @@ -1589,11 +1589,12 @@ static blk_status_t __split_and_process_bio(struct clone_info *ci) struct bio *clone; struct dm_target *ti; unsigned len; - blk_status_t error = BLK_STS_IOERR; ti = dm_table_find_target(ci->map, ci->sector); - if (unlikely(!ti || __process_abnormal_io(ci, ti, &error))) - return error; + if (unlikely(!ti)) + return BLK_STS_IOERR; + else if (unlikely(ci->is_abnormal_io)) + return __process_abnormal_io(ci, ti); /* * Only support bio polling for normal IO, and the target io is @@ -1618,6 +1619,7 @@ static void init_clone_info(struct clone_info *ci, struct mapped_device *md, ci->map = map; ci->io = alloc_io(md, bio); ci->bio = bio; + ci->is_abnormal_io = false; ci->submit_as_polled = false; ci->sector = bio->bi_iter.bi_sector; ci->sector_count = bio_sectors(bio); @@ -1645,6 +1647,13 @@ static void dm_split_and_process_bio(struct mapped_device *md, __send_empty_flush(&ci); /* dm_io_complete submits any data associated with flush */ goto out; + } else if (unlikely(is_abnormal_io(bio))) { + /* + * Use blk_queue_split() for abnormal IO (e.g. discard, etc) + * otherwise associated queue_limits won't be imposed. + */ + blk_queue_split(&bio); + ci.is_abnormal_io = true; } error = __split_and_process_bio(&ci); @@ -1698,13 +1707,6 @@ static void dm_submit_bio(struct bio *bio) goto out; } - /* - * Use blk_queue_split() for abnormal IO (e.g. discard, writesame, etc) - * otherwise associated queue_limits won't be imposed. - */ - if (unlikely(is_abnormal_io(bio))) - blk_queue_split(&bio); - dm_split_and_process_bio(md, map, bio); out: dm_put_live_table_bio(md, srcu_idx, bio); -- 2.15.0 -- dm-devel mailing list [email protected] https://listman.redhat.com/mailman/listinfo/dm-devel
