On Mon, 2011-02-07 at 14:04 -0700, Yehuda Sadeh Weinraub wrote: > On Mon, Feb 7, 2011 at 10:52 AM, Jim Schutt <jaschut@xxxxxxxxxx> wrote: > > > > On Wed, 2011-01-26 at 22:18 -0700, Nick Piggin wrote: > >> On Wed, Jan 26, 2011 at 9:10 AM, Yehuda Sadeh Weinraub > >> <yehudasa@xxxxxxxxx> wrote: > >> > On Wed, Jan 19, 2011 at 2:32 PM, Nick Piggin <npiggin@xxxxxxxxx> wrote: > >> >> On Thu, Jan 20, 2011 at 9:27 AM, Yehuda Sadeh Weinraub > >> >> <yehudasa@xxxxxxxxx> wrote: > >> >>> On Tue, Jan 18, 2011 at 2:42 PM, Nick Piggin <npiggin@xxxxxxxxx> wrote: > >> >>>> On Wed, Jan 19, 2011 at 9:32 AM, Yehuda Sadeh Weinraub > >> >>> > >> >>>>> There's an issue with ceph as it references the > >> >>>>> dentry->d_parent(->d_inode) at dentry_release(), so setting > >> >>>>> dentry->d_parent to NULL here doesn't work with ceph. Though there is > >> >>>>> some workaround for it, we would like to be sure that this one is > >> >>>>> really required so that we don't exacerbate the ugliness. The > >> >>>>> workaround is to keep a pointer to the parent inode in the private > >> >>>>> dentry structure, which will be referenced only at the .release() > >> >>>>> callback. This is clearly not ideal. > >> >>>> > >> >>>> Hmm, I'll have to think about it. Probably we can check for > >> >>>> d_count == 0 rather than parent != NULL I think? > >> >>>> > >> >>> > >> >>> That'll solve ceph's problem, don't know about how'd affect other > >> >>> stuff. We'll need to know whether this is the solution, or whether > >> >>> we'd need to introduce some other band aid fix. > >> >> > >> >> No I think it will work fine. Basically we just need to know whether > >> >> we have been deleted, and if so then we restart rather than walking > >> >> back up the parent. > >> >> > >> >> I'll send a patch in a few days. For the meantime, it's a rathe > >> >> small window for ceph to worry about. So we'll have something > >> >> before -rc2 which should be OK. > >> >> > >> > > >> > I guess that it's a bit late for -rc2, should we assume that it'll be on -rc3? > >> > >> Yeah, I'm sorry I've been travelling and a bit disconnected. > >> > >> NFS folk are having a similar problem and looks like similar > >> proposed fix will do it. > >> > >> http://marc.info/?l=linux-fsdevel&m=129599823927039&w=2 > >> > >> So I think it is the best way to go to restore behaviour back to what > >> filesystems already expect, to avoid more surprises in future. > > > > I think the following BUG indicates I'm hitting this problem? > > All I have to do to cause it is unlink a file. > > > > My ceph client kernel is 8dbdea8444 (master branch) from > > git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6.git > > + e41cdbb6c5 (master branch) + a3f5274e53 (unstable branch) > > from git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client.git > > > > Are there any patches available for this I can test? > > > > Thanks -- Jim > > > > It does look like this specific problem. > You can try cherry-pick commit 9c3db35 off the ceph git. It is just a > temporary workaround, and it wasn't tested too much. Hopefully Nick > will push his fix soon so that it wouldn't be needed. That commit fixes my unlink issue, thanks. I'm happy to use it while things get resolved. -- Jim > > Thanks, > Yehuda > -- > To unsubscribe from this list: send the line "unsubscribe ceph-devel" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
