tree 59124b824744aaf0657c57c986ed77c42d6fc748
parent a8c7176b6ded413d5044a00f1d05477b95a6d7ad
author Jan Kara <jack@suse.cz> 1341326733 +0200
committer Al Viro <viro@zeniv.linux.org.uk> 1342987133 +0400

vfs: Remove unnecessary flushing of block devices

It is not necessary to write block devices twice. The reason why we first did
flush and then proper sync is that
  for_each_bdev() {
    write_bdev()
    wait_for_completion()
  }
is much slower than
  for_each_bdev()
    write_bdev()
  for_each_bdev()
    wait_for_completion()
when there is bigger amount of data. But as is seen in the above, there's no real
need to scan pages and submit them twice. We just need to separate the submission
and waiting part. This patch does that.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>