Commit 2d544564 authored Feb 04, 2008 by Qi Yong Committed by Linus Torvalds Feb 05, 2008

skip writing data pages when inode is under I_SYNC



Since I_SYNC was split out from I_LOCK, the concern in commit
4b89eed9 ("Write back inode data pages
even when the inode itself is locked") is not longer valid.

We should revert to the original behavior: in __writeback_single_inode(),
when we find an I_SYNC-ed inode and we're not doing a data-integrity sync,
skip writing entirely.  Otherwise, we are double calling do_writepages()

Signed-off-by: Qi Yong <qiyong@fc-cn.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Joern Engel <joern@wohnheim.fh-wedel.de>
Cc: WU Fengguang <wfg@mail.ustc.edu.cn>
Cc: Michael Rubin <mrubin@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent 5a9bbdcd

fs/fs-writeback.c

+1 −12

Original line number	Diff line number	Diff line
		@@ -334,9 +334,6 @@ __writeback_single_inode(struct inode inode, struct writeback_control wbc)
		WARN_ON(inode->i_state & I_WILL_FREE);

		if ((wbc->sync_mode != WB_SYNC_ALL) && (inode->i_state & I_SYNC)) {
		struct address_space *mapping = inode->i_mapping;
		int ret;

		/*
		* We're skipping this inode because it's locked, and we're not
		* doing writeback-for-data-integrity. Move it to s_more_io so
		@@ -345,15 +342,7 @@ __writeback_single_inode(struct inode inode, struct writeback_control wbc)
		* completed a full scan of s_io.
		*/
		requeue_io(inode);

		/*
		* Even if we don't actually write the inode itself here,
		* we can at least start some of the data writeout..
		*/
		spin_unlock(&inode_lock);
		ret = do_writepages(mapping, wbc);
		spin_lock(&inode_lock);
		return ret;
		return 0;
		}

		/*