From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from userp1040.oracle.com ([156.151.31.81]:24497 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752529AbbGFDSF (ORCPT ); Sun, 5 Jul 2015 23:18:05 -0400 Date: Mon, 6 Jul 2015 11:17:38 +0800 From: Liu Bo To: Chandan Rajendra Cc: clm@fb.com, jbacik@fb.com, dsterba@suse.cz, linux-btrfs@vger.kernel.org, chandan@mykolab.com Subject: Re: [RFC PATCH V11 12/21] Btrfs: subpagesize-blocksize: Search for all ordered extents that could span across a page. Message-ID: <20150706025900.GA6105@localhost.localdomain> Reply-To: bo.li.liu@oracle.com References: <1433172176-8742-1-git-send-email-chandan@linux.vnet.ibm.com> <1433172176-8742-13-git-send-email-chandan@linux.vnet.ibm.com> <20150701144709.GE7847@localhost.localdomain> <1662899.ajn0RKgkkt@localhost.localdomain> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <1662899.ajn0RKgkkt@localhost.localdomain> Sender: linux-btrfs-owner@vger.kernel.org List-ID: On Fri, Jul 03, 2015 at 03:38:00PM +0530, Chandan Rajendra wrote: > On Wednesday 01 Jul 2015 22:47:10 Liu Bo wrote: > > On Mon, Jun 01, 2015 at 08:52:47PM +0530, Chandan Rajendra wrote: > > > In subpagesize-blocksize scenario it is not sufficient to search using the > > > first byte of the page to make sure that there are no ordered extents > > > present across the page. Fix this. > > > > > > Signed-off-by: Chandan Rajendra > > > --- > > > > > > fs/btrfs/extent_io.c | 3 ++- > > > fs/btrfs/inode.c | 4 ++-- > > > 2 files changed, 4 insertions(+), 3 deletions(-) > > > > > > diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c > > > index 14b4e05..0b017e1 100644 > > > --- a/fs/btrfs/extent_io.c > > > +++ b/fs/btrfs/extent_io.c > > > @@ -3244,7 +3244,8 @@ static int __extent_read_full_page(struct > > > extent_io_tree *tree,> > > > while (1) { > > > > > > lock_extent(tree, start, end); > > > > > > - ordered = btrfs_lookup_ordered_extent(inode, start); > > > + ordered = btrfs_lookup_ordered_range(inode, start, > > > + PAGE_CACHE_SIZE); > > > > A minor suggestion, it'd be better to include the new prototype in the > > same patch, which will be benefit to later cherry-picking or reverting. > > > > Liu, The definition of btrfs_lookup_ordered_range() is already part of > the mainline kernel. Ah, I didn't recognize the difference of btrfs_lookup_ordered_extent and btrfs_lookup_ordered_range, sorry. > > > > > > if (!ordered) > > > > > > break; > > > > > > unlock_extent(tree, start, end); > > > > > > diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c > > > index e9bab73..8b4aaed 100644 > > > --- a/fs/btrfs/inode.c > > > +++ b/fs/btrfs/inode.c > > > > > > @@ -1976,7 +1976,7 @@ again: > > > if (PagePrivate2(page)) > > > > > > goto out; > > > > > > - ordered = btrfs_lookup_ordered_extent(inode, page_start); > > > + ordered = btrfs_lookup_ordered_range(inode, page_start, > > > PAGE_CACHE_SIZE); > > > > > > if (ordered) { > > > > > > unlock_extent_cached(&BTRFS_I(inode)->io_tree, page_start, > > > > > > page_end, &cached_state, GFP_NOFS); > > > > > > @@ -8513,7 +8513,7 @@ static void btrfs_invalidatepage(struct page *page, > > > unsigned int offset,> > > > if (!inode_evicting) > > > > > > lock_extent_bits(tree, page_start, page_end, 0, > &cached_state); > > > > > > - ordered = btrfs_lookup_ordered_extent(inode, page_start); > > > + ordered = btrfs_lookup_ordered_range(inode, page_start, > > > PAGE_CACHE_SIZE); It's possible for a page to hold two (or more) ordered extents here, a while loop is necessary to ensure that every ordered extent is processed properly. Thanks, -liubo > > > > > > if (ordered) { > > > > > > /* > > > > > > * IO on this page will never be started, so we need > > -- > chandan >