From f3986374f94951b0fec6980e5b2dd621c51b215c Mon Sep 17 00:00:00 2001 From: Mike Snitzer Date: Sun, 17 Dec 2017 11:56:48 -0500 Subject: [PATCH] dm: simplify start of block stats accounting for bio-based No apparent need to generic_start_io_acct() until before the IO is ready for submission. start_io_acct() is the proper place to do this accounting -- it is also where DM accounts for pending IO and, if enabled, starts dm-stats accounting. Replace start_io_acct()'s part_round_stats() with generic_start_io_acct(). This eliminates needing to take part_stat_lock() multiple times when starting an IO on bio-based devices. Signed-off-by: Mike Snitzer --- drivers/md/dm.c | 11 +++-------- 1 file changed, 3 insertions(+), 8 deletions(-) diff --git a/drivers/md/dm.c b/drivers/md/dm.c index e4213c4..cbb4ae5 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -599,16 +599,14 @@ static void start_io_acct(struct dm_io *io) { struct mapped_device *md = io->md; struct bio *bio = io->orig_bio; - int cpu; int rw = bio_data_dir(bio); io->start_time = jiffies; - cpu = part_stat_lock(); - part_round_stats(md->queue, cpu, &dm_disk(md)->part0); - part_stat_unlock(); + generic_start_io_acct(md->queue, rw, bio_sectors(bio), &dm_disk(md)->part0); + atomic_set(&dm_disk(md)->part0.in_flight[rw], - atomic_inc_return(&md->pending[rw])); + atomic_inc_return(&md->pending[rw])); if (unlikely(dm_stats_used(&md->stats))) dm_stats_account_io(&md->stats, bio_data_dir(bio), @@ -1556,15 +1554,12 @@ static void __split_and_process_bio(struct mapped_device *md, */ static blk_qc_t dm_make_request(struct request_queue *q, struct bio *bio) { - int rw = bio_data_dir(bio); struct mapped_device *md = q->queuedata; int srcu_idx; struct dm_table *map; map = dm_get_live_table(md, &srcu_idx); - generic_start_io_acct(q, rw, bio_sectors(bio), &dm_disk(md)->part0); - /* if we're suspended, we have to queue this io for later */ if (unlikely(test_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags))) { dm_put_live_table(md, srcu_idx); -- 2.7.4