From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1764361AbYDPNz5 (ORCPT ); Wed, 16 Apr 2008 09:55:57 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753605AbYDPNzt (ORCPT ); Wed, 16 Apr 2008 09:55:49 -0400 Received: from triton.rz.uni-saarland.de ([134.96.7.25]:22748 "EHLO triton.rz.uni-saarland.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752176AbYDPNzs convert rfc822-to-8bit (ORCPT ); Wed, 16 Apr 2008 09:55:48 -0400 Date: Wed, 16 Apr 2008 15:55:08 +0200 From: Alexander van Heukelum To: Ingo Molnar Cc: Alexander van Heukelum , Thomas Gleixner , linux-kernel@vger.kernel.org Subject: [PATCH] x86: fix find_next_bit breakage on ppc and powerpc Message-ID: <20080416135508.GA16439@mailshack.com> References: <1208191719.12568.1247788911@webmail.messagingengine.com> <20080416125724.GC6304@elte.hu> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: 8BIT In-Reply-To: <20080416125724.GC6304@elte.hu> User-Agent: Mutt/1.5.9i X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-3.0 (triton.rz.uni-saarland.de [134.96.7.25]); Wed, 16 Apr 2008 15:55:23 +0200 (CEST) X-AntiVirus: checked by AntiVir MailGate (version: 2.1.2-14; AVE: 7.8.0.6; VDF: 7.0.3.174; host: AntiVir3) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Powerpc (and ppc) have their have some code in their bitops.h which used to be exacly the same as asm-generic/bitops/find.h. Include this header instead. This should also fix the compile problems due to the generic find_next_bit changes. Those were fixed by Thomas Gleixner in asm-generic/bitops/find.h earlier. Signed-off-by: Alexander van Heukelum --- On Wed, Apr 16, 2008 at 02:57:24PM +0200, Ingo Molnar wrote: > * Alexander van Heukelum wrote: > > Hello Thomas, > > > > I see Ingo has applied three fixes to the x86-tree: > > find_first_bit() ppc fix > > powerpc: fix powerpc build > > find_next_bit() fix > > > > Could you please give some insight in what went wrong with > > ppc and powerpc? > > > > "find_first_bit() ppc fix" disables the use of find_first_bit > > for every user of GENERIC_FIND_NEXT_BIT=y. It replaces it by a > > macro to call find_next_bit with offset=0. It should be possible > > for an arch to use GENERIC_FIND_NEXT_BIT=y and implement > > find_first_bit by itself. > > > > "powerpc: fix powerpc build" removes the private 'implementation' > > of asm-generic/bitops/find.h. It seems correct code to me. What > > was the problem here? If it is duplicate declarations, then > > I would suggest putting #ifndef GENERIC_FIND_NEXT_BIT around > > them. > > > > "find_next_bit() fix" changes asm-generic/bitops/find.h to > > declare find_next_bit only if CONFIG_GENERIC_FIND_NEXT_BIT=n. > > That is indeed a good change. It would be better if this > > file disappeared completely, though. > > we had trouble making ppc64 defconfig build fine with your bitops > changes applied (Thomas might still have the build failure logs). The > fixes are ad-hoc band-aids to get it to build. We used crosscompilers to > build on ppc64. Hello, Yeah, I reproduced the breakage on x86 by putting an #include in asm-x86/bitops.h. It's complaining a lot, then. Sorry about that breakage. I should have put more thought in the possibility of breakage due to that header file (I did look at it, but I thought it was harmless). Thomas' "find_next_bit() fix" is certainly needed and correct. Acked-by: Alexander van Heukelum . Could you/Thomas try the following on top of that fix? (i.e., with "find_next_bit() fix" and "find_first_bit() ppc fix" removed?) I think it should work then. Architectures that use CONFIG_GENERIC_FIND_NEXT_BIT=y and include asm-generic/bitops/find.h should be able to switch to the generic find_first_bit implementation by setting GENERIC_FIND_FIRST_BIT=y in asm-$ARCH/Kconfig and removing the #include from their asm-$ARCH/bitops.h. Greetings, Alexander include/asm-powerpc/bitops.h | 17 +---------------- 1 files changed, 1 insertions(+), 16 deletions(-) diff --git a/include/asm-powerpc/bitops.h b/include/asm-powerpc/bitops.h index 2fc0c45..e2dbb53 100644 --- a/include/asm-powerpc/bitops.h +++ b/include/asm-powerpc/bitops.h @@ -318,23 +318,8 @@ static __inline__ unsigned long __fls(unsigned long x) return __ilog2(x); } #include - #include - -#define find_first_zero_bit(addr, size) find_next_zero_bit((addr), (size), 0) -unsigned long find_next_zero_bit(const unsigned long *addr, - unsigned long size, unsigned long offset); -/** - * find_first_bit - find the first set bit in a memory region - * @addr: The address to start the search at - * @size: The maximum size to search - * - * Returns the bit-number of the first set bit, not the number of the byte - * containing a bit. - */ -#define find_first_bit(addr, size) find_next_bit((addr), (size), 0) -unsigned long find_next_bit(const unsigned long *addr, - unsigned long size, unsigned long offset); +#include /* Little-endian versions */