From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arnd Bergmann Subject: [v2] Remaining BKL users, what to do Date: Mon, 18 Oct 2010 17:42:06 +0200 Message-ID: <201010181742.06678.arnd@arndb.de> References: <201009161632.59210.arnd@arndb.de> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <201009161632.59210.arnd@arndb.de> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: Content-Type: Text/Plain; charset="us-ascii" To: codalist@coda.cs.cmu.edu, ksummit-2010-discuss@lists.linux-foundation.org Cc: autofs@linux.kernel.org, linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org, Christoph Hellwig , Mikulas Patocka , Trond Myklebust , Petr Vandrovec , Anders Larsen , Jan Kara , Evgeniy Dushistov , Ingo Molnar , netdev@vger.kernel.org, Samuel Ortiz , Arnaldo Carvalho de Melo , linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, Andrew Hendry , David Miller , Jan Harkes , Bryan Schumaker This is a update on the current progress for the BKL removal, reflecting what is currently in linux-next. Maybe we can briefly discuss this at the kernel summit to decide if we want a quick death of the BKL, i.e. fixing/disabling/staging-out the remaining users in 2.6.38 or rather leave them there indefinitely. On Thursday 16 September 2010, Arnd Bergmann wrote: > The big kernel lock is gone from almost all code in linux-next, this is > the status of what I think will happen to the remaining users: > > drivers/gpu/drm/i810/{i810,i830}_dma.c: > Fixable, but needs someone with the hardware to test. Can probably be > marked CONFIG_BROKEN_ON_SMP if nobody cares. Still open, no good solution for this. > drivers/media/video (V4L): > Mauro is working on it, some drivers get moved to staging while the > others get fixed. An easy workaround would be possible by adding > per-driver mutexes, but Mauro wants to it properly by locking all > the right places. Progressing well, patches are being worked on. > fs/adfs: > Probably not hard to fix, but needs someone to test it. > adfs has only seen janitorial fixes for the last 5 years. > Do we know of any users? Nobody replied. > fs/autofs: > Pretty much dead, replaced by autofs4. I'd suggest moving this > to drivers/staging in 2.6.37 and letting it die there. Now in staging. > fs/coda: > Coda seems to have an active community, but not all of their > code is actually part of linux (pioctl!), while the last official > release is missing many of the cleanups that were don in Linux. > Not sure what to do, if someone is interested, the best way might > be a fresh start with a merger of the mainline linux and the > coda.cs.cmu.edu codebase in drivers/staging. > Just removing the BKL without the Coda community seems like a heap > of pointless work. Jan Harkes showed interest, looks like this will get fixed eventually, but probably not in time for 2.6.37. > fs/freevxfs: > Uses the BKL in readdir and lookup, should be easy to fix. Christoph? Still waiting for confirmation from Christoph Hellwig that the BKL is not needed here. I can do the patch to remove it then. > fs/hpfs: > Looks fixable, if anyone cares. Maybe it's time for retirement in > drivers/staging though. The web page only has a Link to the > linux-2.2 version. No replies. > fs/lockd: > Trond writes that he has someone working on BKL removal here. Bryan Schumaker took care of this, looks like the locking is independent of the fs/locks.c locking now, although it still uses the BKL internally. I assume that this will get fixed as well, doesn't seem hard. As long as lockd uses the BKL, both nfs and nfsd depend on the BKL implicitly. > fs/locks.c: > Patch is under discussion, blocked by work on fs/lockd currently. No longer blocked now, both lockd and ceph can deal with this converted to spinlocks. I will follow up with the final patch once they hit mainline. > fs/ncpfs: > Should be fixable if Petr still cares about it. Otherwise suggest > moving to drivers/staging if there are no users left. Fixed by Petr Vandrovec. > fs/qnx4: > Should be easy to fix, there are only a few places in the code that > use the BKL. Anders? Anders Larsen volunteered. > fs/smbfs: > Last I heard this was considered obsolete. Should be move it to > drivers/staging now? Now in staging. > fs/udf: > Not completely trivial, but probably necessary to fix. Project web > site is dead, I hope that Jan Kara can be motivated to fix it though. Jan Kara volunteered to do it. > fs/ufs: > Evgeniy Dushistov is maintaining this, I hope he can take care of > getting rid of the BKL in UFS. No replies. > kernel/trace/blktrace.c: > Should be easy. Ingo? Steven? Done. > net/appletalk: > net/ipx/af_ipx.c: > net/irda/af_irda.c: > Can probably be saved from retirement in drivers/staging if the > maintainers still care. Samuel Ortiz fixed irda. David Miller volunteered to do appletalk and ipx. > net/x25: > Andrew Hendry has started working on it. Patches have shown up in -next now, I suppose Andrew will finish it soon. Out of the remaining modules, I guess i810/i830, adfs, hpfs and ufs might end up not getting fixed at all, we can either mark them non-SMP or move them to drivers/staging once all the others are done. Arnd From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932801Ab0JRPlz (ORCPT ); Mon, 18 Oct 2010 11:41:55 -0400 Received: from moutng.kundenserver.de ([212.227.17.8]:57963 "EHLO moutng.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932167Ab0JRPlx (ORCPT ); Mon, 18 Oct 2010 11:41:53 -0400 From: Arnd Bergmann To: codalist@TELEMANN.coda.cs.cmu.edu, ksummit-2010-discuss@lists.linux-foundation.org Subject: [v2] Remaining BKL users, what to do Date: Mon, 18 Oct 2010 17:42:06 +0200 User-Agent: KMail/1.12.2 (Linux/2.6.35-16-generic; KDE/4.3.2; x86_64; ; ) Cc: autofs@linux.kernel.org, linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org, Christoph Hellwig , Mikulas Patocka , Trond Myklebust , Petr Vandrovec , Anders Larsen , Jan Kara , Evgeniy Dushistov , Ingo Molnar , netdev@vger.kernel.org, Samuel Ortiz , Arnaldo Carvalho de Melo , linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, Andrew Hendry , David Miller , Jan Harkes , Bryan Schumaker References: <201009161632.59210.arnd@arndb.de> In-Reply-To: <201009161632.59210.arnd@arndb.de> MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Message-Id: <201010181742.06678.arnd@arndb.de> X-Provags-ID: V02:K0:pSnB9rTTk0Wjcu0Lxh71tavU4twJxvMQzOlQYrJQL8r WLZNoCnCsUITI50PSYAKS8RZ/WWyKtxgFe/QcFqzMx1c1Bfm+L Oc8dmddr2QG9uCPQMXZjiEyjbTy2K3WX9QsKM9dqxxSOePsik5 pMA+5HsvMFlM0bYa73Z8NGS/fMQAQruaTOwBpfooeGSxUzwau7 T7kY8wCnCermQBFdD33qg== Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This is a update on the current progress for the BKL removal, reflecting what is currently in linux-next. Maybe we can briefly discuss this at the kernel summit to decide if we want a quick death of the BKL, i.e. fixing/disabling/staging-out the remaining users in 2.6.38 or rather leave them there indefinitely. On Thursday 16 September 2010, Arnd Bergmann wrote: > The big kernel lock is gone from almost all code in linux-next, this is > the status of what I think will happen to the remaining users: > > drivers/gpu/drm/i810/{i810,i830}_dma.c: > Fixable, but needs someone with the hardware to test. Can probably be > marked CONFIG_BROKEN_ON_SMP if nobody cares. Still open, no good solution for this. > drivers/media/video (V4L): > Mauro is working on it, some drivers get moved to staging while the > others get fixed. An easy workaround would be possible by adding > per-driver mutexes, but Mauro wants to it properly by locking all > the right places. Progressing well, patches are being worked on. > fs/adfs: > Probably not hard to fix, but needs someone to test it. > adfs has only seen janitorial fixes for the last 5 years. > Do we know of any users? Nobody replied. > fs/autofs: > Pretty much dead, replaced by autofs4. I'd suggest moving this > to drivers/staging in 2.6.37 and letting it die there. Now in staging. > fs/coda: > Coda seems to have an active community, but not all of their > code is actually part of linux (pioctl!), while the last official > release is missing many of the cleanups that were don in Linux. > Not sure what to do, if someone is interested, the best way might > be a fresh start with a merger of the mainline linux and the > coda.cs.cmu.edu codebase in drivers/staging. > Just removing the BKL without the Coda community seems like a heap > of pointless work. Jan Harkes showed interest, looks like this will get fixed eventually, but probably not in time for 2.6.37. > fs/freevxfs: > Uses the BKL in readdir and lookup, should be easy to fix. Christoph? Still waiting for confirmation from Christoph Hellwig that the BKL is not needed here. I can do the patch to remove it then. > fs/hpfs: > Looks fixable, if anyone cares. Maybe it's time for retirement in > drivers/staging though. The web page only has a Link to the > linux-2.2 version. No replies. > fs/lockd: > Trond writes that he has someone working on BKL removal here. Bryan Schumaker took care of this, looks like the locking is independent of the fs/locks.c locking now, although it still uses the BKL internally. I assume that this will get fixed as well, doesn't seem hard. As long as lockd uses the BKL, both nfs and nfsd depend on the BKL implicitly. > fs/locks.c: > Patch is under discussion, blocked by work on fs/lockd currently. No longer blocked now, both lockd and ceph can deal with this converted to spinlocks. I will follow up with the final patch once they hit mainline. > fs/ncpfs: > Should be fixable if Petr still cares about it. Otherwise suggest > moving to drivers/staging if there are no users left. Fixed by Petr Vandrovec. > fs/qnx4: > Should be easy to fix, there are only a few places in the code that > use the BKL. Anders? Anders Larsen volunteered. > fs/smbfs: > Last I heard this was considered obsolete. Should be move it to > drivers/staging now? Now in staging. > fs/udf: > Not completely trivial, but probably necessary to fix. Project web > site is dead, I hope that Jan Kara can be motivated to fix it though. Jan Kara volunteered to do it. > fs/ufs: > Evgeniy Dushistov is maintaining this, I hope he can take care of > getting rid of the BKL in UFS. No replies. > kernel/trace/blktrace.c: > Should be easy. Ingo? Steven? Done. > net/appletalk: > net/ipx/af_ipx.c: > net/irda/af_irda.c: > Can probably be saved from retirement in drivers/staging if the > maintainers still care. Samuel Ortiz fixed irda. David Miller volunteered to do appletalk and ipx. > net/x25: > Andrew Hendry has started working on it. Patches have shown up in -next now, I suppose Andrew will finish it soon. Out of the remaining modules, I guess i810/i830, adfs, hpfs and ufs might end up not getting fixed at all, we can either mark them non-SMP or move them to drivers/staging once all the others are done. Arnd