From: Jens Axboe Date: Mon, 6 Apr 2009 12:48:04 +0000 (+0200) Subject: jbd: use WRITE_SYNC_PLUG instead of WRITE_SYNC X-Git-Tag: v2.6.30-rc1~192 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=6c4bac6b3351fd278dc3537dae42f88f733ff12e;p=platform%2Fupstream%2Fkernel-adaptation-pc.git jbd: use WRITE_SYNC_PLUG instead of WRITE_SYNC When you are going to be submitting several sync writes, we want to give the IO scheduler a chance to merge some of them. Instead of using the implicitly unplugging WRITE_SYNC variant, use WRITE_SYNC_PLUG and rely on sync_buffer() doing the unplug when someone does a wait_on_buffer()/lock_buffer(). Signed-off-by: Jens Axboe Signed-off-by: Linus Torvalds --- diff --git a/fs/jbd/commit.c b/fs/jbd/commit.c index f8077b9..a8e8513 100644 --- a/fs/jbd/commit.c +++ b/fs/jbd/commit.c @@ -351,8 +351,13 @@ void journal_commit_transaction(journal_t *journal) spin_lock(&journal->j_state_lock); commit_transaction->t_state = T_LOCKED; + /* + * Use plugged writes here, since we want to submit several before + * we unplug the device. We don't do explicit unplugging in here, + * instead we rely on sync_buffer() doing the unplug for us. + */ if (commit_transaction->t_synchronous_commit) - write_op = WRITE_SYNC; + write_op = WRITE_SYNC_PLUG; spin_lock(&commit_transaction->t_handle_lock); while (commit_transaction->t_updates) { DEFINE_WAIT(wait);