On Wed, 2009-12-23 at 19:05 +0100, Jan Kara wrote: > On Wed 23-12-09 15:21:47, Trond Myklebust wrote: > > @@ -474,6 +482,18 @@ writeback_single_inode(struct inode *inode, struct writeback_control *wbc) > > } > > > > spin_lock(&inode_lock); > > + /* > > + * Special state for cleaning NFS unstable pages > > + */ > > + if (inode->i_state & I_UNSTABLE_PAGES) { > > + int err; > > + inode->i_state &= ~I_UNSTABLE_PAGES; > > + spin_unlock(&inode_lock); > > + err = commit_unstable_pages(inode, wait); > > + if (ret == 0) > > + ret = err; > > + spin_lock(&inode_lock); > > + } > I don't quite understand this chunk: We've called writeback_single_inode > because it had some dirty pages. Thus it has I_DIRTY_DATASYNC set and a few > lines above your chunk, we've called nfs_write_inode which sent commit to > the server. Now here you sometimes send the commit again? What's the > purpose? We no longer set I_DIRTY_DATASYNC. We only set I_DIRTY_PAGES (and later I_UNSTABLE_PAGES). The point is that we now do the commit only _after_ we've sent all the dirty pages, and waited for writeback to complete, whereas previously we did it in the wrong order. Cheers Trond -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html