From patchwork Thu Aug 31 09:56:23 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Masahiro Yamada X-Patchwork-Id: 111366 Delivered-To: patch@linaro.org Received: by 10.140.95.112 with SMTP id h103csp2295537qge; Thu, 31 Aug 2017 02:58:19 -0700 (PDT) X-Google-Smtp-Source: ADKCNb4Qgb+1BEt+VDbz2FME/E4pgAl4rteba9lrJOpsTFyIk90erFRlDAi1Oten6AyQdU+7lQ9W X-Received: by 10.99.97.67 with SMTP id v64mr1731438pgb.425.1504173499740; Thu, 31 Aug 2017 02:58:19 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1504173499; cv=none; d=google.com; s=arc-20160816; b=Wdm6Cp+TwHrWLoh1CWmHOEVwWDzumK3bqGRjyQPIcyf72GPWfOzwCRjR3r6a/Rr5f1 F9R1KSF91GB29LtQy5Jh8Rt6s89jhitMEXxF0fuyvVyEAkADU6waWCAgW/tSxB9ZsCsV xu1NAxsConA/u45t1UA4SELh6gI9JTnHPmt8tlC5UlKXqpX4IHWaZlO1LHfYlWa3H6UM JeUSiZfT1l6W0uJ6/UjxI9FYKOC31FUQ/NIuwbGbJMfMFz/TNU8GNDPlZZRqzOErAeCq aGOLgMzvPQCo4NlpRtAFK10/0ozZpBhq5rFrdr/QNWuwjiKlkWLm5ryK8lyaiB2xdzZn pG6Q== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:message-id:date:subject:cc:to:from :dkim-signature:dkim-filter:arc-authentication-results; bh=GcqbPrSsh1FS9h6M2FlW1e/+aBe1jXkK4N6SGPOEQSE=; b=THZa61FmTN18Nj49RbwipgbkMJX/O+8s+xdwD/9yOvr+DcP/XttqStQiJlqdnJq+bW 18Z6K73ajAXjwN7VNjRKRsAl+HiKDa/ObsZvvTS6KENjbLh6NfJeacp7GdXvBeESwCnV Lx93DoIZsxnJ+zXllGzrF1lnOiwlIu8Nwh5fwjfU6yRzDMYXuxpaWHoDRAhqtbODfM+x /13hj/UB1G+gsjb++K6LC6B1t4jp+cs3EcKwVUP/EDmYo04BaniDC9ngWo3Hjk2JLiNF q8bv9BLLawB0ljFDWY5J5kwr0+az1T72iegZdMJi9ITSxFSUsbHGuoHOPoD/q+85ExQu Ti9Q== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@nifty.com header.s=dec2015msa header.b=2tu+HWim; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id l3si6263175pgn.549.2017.08.31.02.58.19; Thu, 31 Aug 2017 02:58:19 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; dkim=pass header.i=@nifty.com header.s=dec2015msa header.b=2tu+HWim; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751409AbdHaJ6R (ORCPT + 26 others); Thu, 31 Aug 2017 05:58:17 -0400 Received: from conuserg-07.nifty.com ([210.131.2.74]:30791 "EHLO conuserg-07.nifty.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751332AbdHaJ6P (ORCPT ); Thu, 31 Aug 2017 05:58:15 -0400 Received: from pug.e01.socionext.com (p14092-ipngnfx01kyoto.kyoto.ocn.ne.jp [153.142.97.92]) (authenticated) by conuserg-07.nifty.com with ESMTP id v7V9uaqW001078; Thu, 31 Aug 2017 18:56:37 +0900 DKIM-Filter: OpenDKIM Filter v2.10.3 conuserg-07.nifty.com v7V9uaqW001078 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nifty.com; s=dec2015msa; t=1504173398; bh=GcqbPrSsh1FS9h6M2FlW1e/+aBe1jXkK4N6SGPOEQSE=; h=From:To:Cc:Subject:Date:From; b=2tu+HWimBVcii/63Lt0i+blOC4mxZP96BJZ5eNYycTv7b33qtugEyyD4ELmTGRY02 MebfZK2pCuqSXCuZP77jXTX34vTQ/glgMwFwnYDCMqaYg5t6PUUWJ9Oi0O3bbH6eqo aEPFf1Q7Bj8seFYzZwSRUSQiFcvHxJo3SmTENxoi9y/CjUsgtRUfAFTahjBROe3ZDM GB9DoRQ2SKK78yPQr0ZnMM8ftLucD6kazuXP+ziMceH04zmTDNaA5e7A/Kg+9FkS9I xUjtaux+P1smw86ks+iCJqCo3ywZ22CUvFxYRYMOLU5yog3+x8Fr/E/FyRJTl/2c/9 ws/daXHPBScSA== X-Nifty-SrcIP: [153.142.97.92] From: Masahiro Yamada To: linux-arm-kernel@lists.infradead.org, Will Deacon , Catalin Marinas Cc: Olof Johansson , Arnd Bergmann , Rob Herring , Russell King , Marc Zyngier , Masahiro Yamada , linux-kernel@vger.kernel.org Subject: [PATCH] arm64: relax assembly code alignment from 16 byte to 4 byte Date: Thu, 31 Aug 2017 18:56:23 +0900 Message-Id: <1504173383-8367-1-git-send-email-yamada.masahiro@socionext.com> X-Mailer: git-send-email 2.7.4 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Aarch64 instructions must be word aligned. The current 16 byte alignment is more than enough. Relax it into 4 byte alignment. Signed-off-by: Masahiro Yamada --- I do not know why arm64 Linux requires 16 byte alignment. I dug git-history of arch/arm64/include/asm/linkage.h and the only commit I see is: commit aeed41a9371ee02257b608eb06a9058507a7d0f4 Author: Marc Zyngier Date: Fri Oct 19 17:33:27 2012 +0100 arm64: fix alignment padding in assembly code It just opt out of the asm-generic variant to remove 0x90. So, the amount of alignment might not be not optimized yet. Please correct me if I am missing something. arch/arm64/include/asm/linkage.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) -- 2.7.4 diff --git a/arch/arm64/include/asm/linkage.h b/arch/arm64/include/asm/linkage.h index 636c1bc..1b26629 100644 --- a/arch/arm64/include/asm/linkage.h +++ b/arch/arm64/include/asm/linkage.h @@ -1,7 +1,7 @@ #ifndef __ASM_LINKAGE_H #define __ASM_LINKAGE_H -#define __ALIGN .align 4 -#define __ALIGN_STR ".align 4" +#define __ALIGN .align 2 +#define __ALIGN_STR ".align 2" #endif