From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758204Ab0ERUK4 (ORCPT ); Tue, 18 May 2010 16:10:56 -0400 Received: from mail-fx0-f46.google.com ([209.85.161.46]:43477 "EHLO mail-fx0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752906Ab0ERUKy (ORCPT ); Tue, 18 May 2010 16:10:54 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=subject:from:to:cc:in-reply-to:references:content-type:date :message-id:mime-version:x-mailer:content-transfer-encoding; b=eLW3TX049Nf+jOwePlE/J9JEt13/x/4KyR/4qMn37IMbfuNU7vyb12mba2NY0s4FcO VRyh11wB7l3XGR09TE7dRYkmrQafUwWnFMLzuqOHIcMqnXAM1nXBxS/wwLv8cLR5vVZU YdcPb9wglbOPJ8EQySjpFKMeu0tiQ09g+1WoY= Subject: Re: [tip:x86/fpu] x86: Add new static_cpu_has() function using alternatives From: Eric Dumazet To: mingo@redhat.com, hpa@zytor.com, linux-kernel@vger.kernel.org, suresh.b.siddha@intel.com, tglx@linutronix.de, avi@redhat.com Cc: linux-tip-commits@vger.kernel.org In-Reply-To: References: <1273135546-29690-2-git-send-email-avi@redhat.com> Content-Type: text/plain; charset="UTF-8" Date: Tue, 18 May 2010 22:10:43 +0200 Message-ID: <1274213443.2485.3.camel@edumazet-laptop> Mime-Version: 1.0 X-Mailer: Evolution 2.28.3 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Le mercredi 12 mai 2010 à 01:06 +0000, tip-bot for H. Peter Anvin a écrit : > Commit-ID: a3c8acd04376d604370dcb6cd2143c9c14078a50 > Gitweb: http://git.kernel.org/tip/a3c8acd04376d604370dcb6cd2143c9c14078a50 > Author: H. Peter Anvin > AuthorDate: Tue, 11 May 2010 17:47:07 -0700 > Committer: H. Peter Anvin > CommitDate: Tue, 11 May 2010 17:47:07 -0700 > > x86: Add new static_cpu_has() function using alternatives > > For CPU-feature-specific code that touches performance-critical paths, > introduce a static patching version of [boot_]cpu_has(). This is run > at alternatives time and is therefore not appropriate for most > initialization code, but on the other hand initialization code is > generally not performance critical. > > On gcc 4.5+ this uses the new "asm goto" feature. Might be time to change Documentation/Changes about gcc requirements ... # make CHK include/linux/version.h CHK include/generated/utsrelease.h CALL scripts/checksyscalls.sh CHK include/generated/compile.h CC arch/x86/kernel/process_32.o /usr/src/linux-2.6/arch/x86/include/asm/cpufeature.h: In function `prepare_to_copy': /usr/src/linux-2.6/arch/x86/include/asm/cpufeature.h:315: warning: asm operand 1 probably doesn't match constraints /usr/src/linux-2.6/arch/x86/include/asm/cpufeature.h:315: error: impossible constraint in `asm' /usr/src/linux-2.6/arch/x86/include/asm/cpufeature.h:313: warning: 'flag' might be used uninitialized in this function make[2]: *** [arch/x86/kernel/process_32.o] Error 1 make[1]: *** [arch/x86/kernel] Error 2 make: *** [arch/x86] Error 2 # gcc -v Reading specs from /usr/lib/gcc/i386-redhat-linux/3.4.6/specs Configured with: ../configure --prefix=/usr --mandir=/usr/share/man --infodir=/usr/share/info --enable-shared --enable-threads=posix --disable-checking --with-system-zlib --enable-__cxa_atexit --disable-libunwind-exceptions --enable-java-awt=gtk --host=i386-redhat-linux Thread model: posix gcc version 3.4.6 20060404 (Red Hat 3.4.6-10)