Re: [PATCH v11 00/13] Btrfs dedupe framework

[Chandan Rajendra <chandan@linux.vnet.ibm.com>]

On Saturday, June 25, 2016 09:22:44 AM Qu Wenruo wrote:
> 
> On 06/24/2016 05:29 PM, Chandan Rajendra wrote:
> > On Friday, June 24, 2016 10:50:41 AM Qu Wenruo wrote:
> >> Hi Chandan, David,
> >>
> >> When I'm trying to rebase dedupe patchset on top of Chadan's sub page
> >> size patchset (using David's for-next-test-20160620), although the
> >> rebase itself is quite simple, but I'm afraid that I found some bugs for
> >> sub page size patchset, *without* dedupe patchset applied.
> >>
> >> These bugs seems to be unrelated to each other
> >> 1) state leak at btrfs rmmod time
> >
> > The leak was due to not freeing 'cached_state' in
> > read_extent_buffer_pages(). I have fixed this and the fix will be part of the
> > patchset when I post the next version to the mailing list.
> >
> > I have always compiled the btrfs code as part of the vmlinux image and hence
> > have never rmmod the btrfs module during my local testing. The space leak
> > messages might have appeared when I shut down my guest. Hence I had never
> > noticed them before. Thanks once again for informing me about it.
> >
> >> 2) bytes_may_use leak at qgroup EDQUOTA error time
> >
> > I have a slightly older version of btrfs-progs which does not yet have btrfs
> > dedupe" command. I will get the new version and check if the space leak can be
> > reproduced on my machine.
> >
> > However, I don't see the space leak warning messages when the reproducer
> > script is executed after commenting out "btrfs dedupe enable $mnt".
> 
> Strange.
> That dedupe command is not useful at all, as I'm using the branch 
> without the dedupe patchset.
> Even with btrfs-progs dedupe patchset, dedupe enable only output ENOTTY 
> error message.
> 
> I'll double check if it's related to the dedupe.
> 
> BTW, are you testing with 4K page size?

Yes, I executed the script with 4k page size. I had based my patchset on top
of 4.7-rc2 kernel. If you are interested, you can get the kernel sources at
'https://github.com/chandanr/linux subpagesize-blocksize'.

I will soon rebase my patchset on David's master branch. I will let you know
if I hit the space leak issue on the rebased kernel.

-- 
chandan