From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andi Kleen Subject: Re: [PATCH 2/5] kbuild: allow archs to select build for link dead code/data elimination Date: Mon, 8 Aug 2016 20:16:05 -0700 Message-ID: <20160809031605.GF3078@tassilo.jf.intel.com> References: <1470399123-8455-1-git-send-email-npiggin@gmail.com> <12986071.MeSB5hmlsH@wuerfel> <20160807234947.GV20904@bubble.grove.modra.org> <1882847.dG563Vieov@wuerfel> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <1882847.dG563Vieov@wuerfel> Sender: linux-kbuild-owner@vger.kernel.org To: Arnd Bergmann Cc: Alan Modra , linuxppc-dev@lists.ozlabs.org, Nicholas Piggin , linux-arch@vger.kernel.org, Stephen Rothwell , Nicolas Pitre , linux-kbuild@vger.kernel.org List-Id: linux-arch.vger.kernel.org > I don't understand what led Andi Kleen to also move .text.hot and > .text.unlikely together with .text [2], but this may have > been a related issue. The goal was just to move .hot and .unlikely all together, so that they are clustered and use the minimum amount of cache. On x86 doesn't matter where they are exactly, as long as each is together. If they are not explicitely listed then the linker interleaves them with the normal text, which defeats the purpose. -Andi From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga01.intel.com ([192.55.52.88]:49276 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752234AbcHIDQH (ORCPT ); Mon, 8 Aug 2016 23:16:07 -0400 Date: Mon, 8 Aug 2016 20:16:05 -0700 From: Andi Kleen Subject: Re: [PATCH 2/5] kbuild: allow archs to select build for link dead code/data elimination Message-ID: <20160809031605.GF3078@tassilo.jf.intel.com> References: <1470399123-8455-1-git-send-email-npiggin@gmail.com> <12986071.MeSB5hmlsH@wuerfel> <20160807234947.GV20904@bubble.grove.modra.org> <1882847.dG563Vieov@wuerfel> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1882847.dG563Vieov@wuerfel> Sender: linux-arch-owner@vger.kernel.org List-ID: To: Arnd Bergmann Cc: Alan Modra , linuxppc-dev@lists.ozlabs.org, Nicholas Piggin , linux-arch@vger.kernel.org, Stephen Rothwell , Nicolas Pitre , linux-kbuild@vger.kernel.org Message-ID: <20160809031605.3IoQ4g-Me3CfjakXpVMJLeGci5_vZdOUO-Lfq7WFbh8@z> > I don't understand what led Andi Kleen to also move .text.hot and > .text.unlikely together with .text [2], but this may have > been a related issue. The goal was just to move .hot and .unlikely all together, so that they are clustered and use the minimum amount of cache. On x86 doesn't matter where they are exactly, as long as each is together. If they are not explicitely listed then the linker interleaves them with the normal text, which defeats the purpose. -Andi