From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.4 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2DD85C04A6B for ; Mon, 6 May 2019 16:53:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 02E65205ED for ; Mon, 6 May 2019 16:53:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726685AbfEFQxk (ORCPT ); Mon, 6 May 2019 12:53:40 -0400 Received: from gate.crashing.org ([63.228.1.57]:46602 "EHLO gate.crashing.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726321AbfEFQxk (ORCPT ); Mon, 6 May 2019 12:53:40 -0400 Received: from gate.crashing.org (localhost.localdomain [127.0.0.1]) by gate.crashing.org (8.14.1/8.14.1) with ESMTP id x46GrE4M001810; Mon, 6 May 2019 11:53:14 -0500 Received: (from segher@localhost) by gate.crashing.org (8.14.1/8.14.1/Submit) id x46GrEon001809; Mon, 6 May 2019 11:53:14 -0500 X-Authentication-Warning: gate.crashing.org: segher set sender to segher@kernel.crashing.org using -f Date: Mon, 6 May 2019 11:53:14 -0500 From: Segher Boessenkool To: Christophe Leroy Cc: linux-kernel@vger.kernel.org, Scott Wood , Paul Mackerras , linuxppc-dev@lists.ozlabs.org Subject: Re: [PATCH] powerpc/32: Remove memory clobber asm constraint on dcbX() functions Message-ID: <20190506165314.GC8599@gate.crashing.org> References: <20180109065759.4E54B6C73D@localhost.localdomain> <20190503181508.GQ8599@gate.crashing.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.4.2.3i Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi! On Mon, May 06, 2019 at 04:31:38PM +0000, Christophe Leroy wrote: > However, I've tried your suggestion below and get unnexpected result. > >you can do > > > > __asm__ __volatile__ ("dcbf %0" : : "Z"(addr) : "memory"); > > > >to save some insns here and there. ] This should be "dcbf %y0". Sorry. And not addr -- it needs a mem there, so deref addr as usual. Segher