[PATCH] md: use REQ_NOIDLE flag in md_super_write()

From: Namhyung Kim
Date: Wed Aug 03 2011 - 12:00:15 EST


Queue idling is used for the anticipation of immediate
sequencial I/O's but md_super_write() is a kind of one-
shot operation, coupled with md_super_wait(), so the
idling in this case will be just a waste of time.

Specifying REQ_NOIDLE prevents it. Instead of adding
the flag to submit_bio() directly, use pre-defined
macro WRITE_FLUSH_FUA.

Signed-off-by: Namhyung Kim <namhyung@xxxxxxxxx>
---
drivers/md/md.c | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/drivers/md/md.c b/drivers/md/md.c
index d97a62534798..8650e9a0ce7c 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -848,7 +848,7 @@ void md_super_write(mddev_t *mddev, mdk_rdev_t *rdev,
bio->bi_end_io = super_written;

atomic_inc(&mddev->pending_writes);
- submit_bio(REQ_WRITE | REQ_SYNC | REQ_FLUSH | REQ_FUA, bio);
+ submit_bio(WRITE_FLUSH_FUA, bio);
}

void md_super_wait(mddev_t *mddev)
--
1.7.6

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