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| author | Christoph Hellwig <hch@lst.de> | 2024-06-27 15:49:11 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-10-10 12:57:18 +0300 |
| commit | b66ff9a3fc90e27855418a56b7ccbc7b00d38751 (patch) | |
| tree | 61246f624e894e05f9e8a0293fe9154147964c41 | |
| parent | 3000f3a86dd018b2f1f9b15b5c5d1fedae76234b (diff) | |
| download | linux-b66ff9a3fc90e27855418a56b7ccbc7b00d38751.tar.xz | |
loop: don't set QUEUE_FLAG_NOMERGES
[ Upstream commit 667ea36378cf7f669044b27871c496e1559c872a ]
QUEUE_FLAG_NOMERGES isn't really a driver interface, but a user tunable.
There also isn't any good reason to set it in the loop driver.
The original commit adding it (5b5e20f421c0b6d "block: loop: set
QUEUE_FLAG_NOMERGES for request queue of loop") claims that "It doesn't
make sense to enable merge because the I/O submitted to backing file is
handled page by page." which of course isn't true for multi-page bvec
now, and it never has been for direct I/O, for which commit 40326d8a33d
("block/loop: allow request merge for directio mode") alredy disabled
the nomerges flag.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20240627124926.512662-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | drivers/block/loop.c | 15 |
1 files changed, 2 insertions, 13 deletions
diff --git a/drivers/block/loop.c b/drivers/block/loop.c index 552f56a84a7e..886c63599037 100644 --- a/drivers/block/loop.c +++ b/drivers/block/loop.c @@ -211,13 +211,10 @@ static void __loop_update_dio(struct loop_device *lo, bool dio) if (lo->lo_state == Lo_bound) blk_mq_freeze_queue(lo->lo_queue); lo->use_dio = use_dio; - if (use_dio) { - blk_queue_flag_clear(QUEUE_FLAG_NOMERGES, lo->lo_queue); + if (use_dio) lo->lo_flags |= LO_FLAGS_DIRECT_IO; - } else { - blk_queue_flag_set(QUEUE_FLAG_NOMERGES, lo->lo_queue); + else lo->lo_flags &= ~LO_FLAGS_DIRECT_IO; - } if (lo->lo_state == Lo_bound) blk_mq_unfreeze_queue(lo->lo_queue); } @@ -2039,14 +2036,6 @@ static int loop_add(int i) blk_queue_max_hw_sectors(lo->lo_queue, BLK_DEF_MAX_SECTORS); /* - * By default, we do buffer IO, so it doesn't make sense to enable - * merge because the I/O submitted to backing file is handled page by - * page. For directio mode, merge does help to dispatch bigger request - * to underlayer disk. We will enable merge once directio is enabled. - */ - blk_queue_flag_set(QUEUE_FLAG_NOMERGES, lo->lo_queue); - - /* * Disable partition scanning by default. The in-kernel partition * scanning can be requested individually per-device during its * setup. Userspace can always add and remove partitions from all |