From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mout.gmx.net ([212.227.15.19]:60288 "EHLO mout.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752651AbdHNXjq (ORCPT ); Mon, 14 Aug 2017 19:39:46 -0400 Subject: Re: btrfs-progs-v4.12: cross compiling To: kreijack@inwind.it, dsterba@suse.cz, Hallo32 , linux-btrfs@vger.kernel.org References: <20170814130608.GS2866@twin.jikos.cz> <46edbc7c-8bd9-0507-950e-be5182356772@gmx.com> <20170814140341.GU2866@suse.cz> <159b3db0-6eae-7cff-d166-3c4b0c2513ac@gmx.com> <20170814151052.GV2866@twin.jikos.cz> <340e3677-4abd-5390-58bb-a64160a31862@libero.it> From: Qu Wenruo Message-ID: <880007a9-4882-e4a6-7411-a262e5296ab0@gmx.com> Date: Tue, 15 Aug 2017 07:39:34 +0800 MIME-Version: 1.0 In-Reply-To: <340e3677-4abd-5390-58bb-a64160a31862@libero.it> Content-Type: text/plain; charset=utf-8; format=flowed Sender: linux-btrfs-owner@vger.kernel.org List-ID: On 2017年08月15日 02:57, Goffredo Baroncelli wrote: > On 08/14/2017 05:10 PM, David Sterba wrote: >> On Mon, Aug 14, 2017 at 10:14:42PM +0800, Qu Wenruo wrote: > [...] >> mktables.c is synced from kernel sources, taking updates from there is >> easier than porting any changes to the proposed scripted implementation. >> >> The workflow is simple: >> - copy kernel mktables.c changes to btrfs-progs mktables.c > > How the kernel deals with this kind of problem ? > Looking at the source of btrfs Makefile, it is more simple to replace > > mktables: kernel-lib/mktables.c > @echo " [CC] $@" > $(Q)$(CC) $(CFLAGS) $< -o $@ > > with > > > mktables: kernel-lib/mktables.c > @echo " [HOSTCC] $@" > $(Q)$(HOSTCC) $(CFLAGS) $< -o $@ > > where HOSTCC is defined as > > HOSTCC=gcc > > > (may be the same applied also to CFLAGS <-> HOSTCFLAGS ?) If using HOSTCC then I'm fine with it. Thanks, Qu > >> - compile mktables >> - run 'make kernel-lib/tables.c' >> - commit the changes to git >> >> All of that happens very rarely, if ever, the raid56 tables and >> correction algorithms are set in stone. Any extensions need to be done >> on both sides kernel/userspace. >> >>>>> What about using script to generate it? >>>> >>>> We do have the mktables utility to generate it and I'll regenerate it >>>> should there be a change to kernel-lib/mktables.c >>> >>> I mean to replace mktables.c with a script. >>> So no cross compiler problems at all, and even easier Makefile. >>> No dependence on "mktables" program. >> >> Somebody has to implement the script and verify that the output is the >> same, eventually sync changes. The cross-compilation should be fixed >> with the pregenerated tables.c . Is Makefile size really a concern? The >> number of related lines is like 7. I don't see any benefit in what you >> propose and hopefully explained my viewpoint enough so I don't have to >> continue. >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in >> the body of a message to majordomo@vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html >> > >