Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761072AbZDXRvN (ORCPT ); Fri, 24 Apr 2009 13:51:13 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1758250AbZDXRuw (ORCPT ); Fri, 24 Apr 2009 13:50:52 -0400 Received: from bombadil.infradead.org ([18.85.46.34]:53468 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753467AbZDXRuv (ORCPT ); Fri, 24 Apr 2009 13:50:51 -0400 Date: Fri, 24 Apr 2009 13:50:25 -0400 From: Christoph Hellwig To: Fr?d?ric Weisbecker Cc: Christoph Hellwig , Ingo Molnar , Al Viro , Alessio Igor Bogani , Jonathan Corbet , Peter Zijlstra , LKML , LFSDEV , Linus Torvalds , Matthew Wilcox Subject: Re: [PATCH 1/1] vfs: umount_begin BKL pushdown v2 Message-ID: <20090424175025.GA30091@infradead.org> References: <20090423191934.GW1926@parisc-linux.org> <1240556813-8739-1-git-send-email-abogani@texware.it> <1240556813-8739-2-git-send-email-abogani@texware.it> <20090424071312.GE8633@ZenIV.linux.org.uk> <20090424071853.GG8633@ZenIV.linux.org.uk> <20090424080634.GG24912@elte.hu> <20090424085017.GB28592@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.18 (2008-05-17) X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1764 Lines: 39 On Fri, Apr 24, 2009 at 11:16:18AM +0200, Fr?d?ric Weisbecker wrote: > I disagree with you. The kill-the-BKL tree does not only aggregate patches > to turn the BKL into more traditional locks. The Bkl has been > converted to a common mutex in > this tree, making it losing its common horrid properties: > > - release/reacquire on schedule > - not preemptable > - can be reacquired recursively by a same task > > Such a basis is very useful because we can easily find these places > which won't support a usual lock conversion without reworking the > locking scheme. > This is a necessary preliminary for the Bkl removal. > All the places which have been designed very tightly with Bkl > properties are rapidly detected > with lockdep in this tree and reworked, still using lockdep, code > reviewing and the help of > this Bkl-to-mutex conversion. > > The work done with this tree can be merged inside and also on the > matching subsytem tree for > each patchset. That's a very sane workflow IMHO. Having a working tree for debugging stuff is fine, but the point is that it should never be pulled into mainline and probably frequently reabsed to avoid cruft. In that case there's really no point in creating branches to share pieces of tree history, just apply the patch locally if you think you want it and merge or rebase once mainline gets the patch. Al frequently rebases the vfs tree, btw - so even if it was a separate branch now there's a fair chance it would end up in mainline with a different commit id. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/