From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756618AbZBKPPM (ORCPT ); Wed, 11 Feb 2009 10:15:12 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754378AbZBKPO6 (ORCPT ); Wed, 11 Feb 2009 10:14:58 -0500 Received: from ti-out-0910.google.com ([209.85.142.187]:19615 "EHLO ti-out-0910.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752351AbZBKPO6 (ORCPT ); Wed, 11 Feb 2009 10:14:58 -0500 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:user-agent:mime-version:to:cc:subject :references:in-reply-to:x-enigmail-version:content-type :content-transfer-encoding; b=jiAouuRp/HDll1igTbvE4/J1WtiWBEsgsxN9GEs9KSoDNSimVymGbHP7XjwnnuSrgC MerxRhGtpFWWLqWDxrTJIiGJv11Q0OCh/OD4J8sogcFiSBvA1x7Gz1QpMKzU5ioePsuH inCLsVeM3miv7uPUuhw+RM/+Ai5LE0EmtzxFM= Message-ID: <4992EB62.3000501@gmail.com> Date: Thu, 12 Feb 2009 00:14:42 +0900 From: Tejun Heo User-Agent: Thunderbird 2.0.0.19 (X11/20081227) MIME-Version: 1.0 To: Brian Gerst CC: Ingo Molnar , linux-kernel@vger.kernel.org Subject: Re: [PATCH 2/3] x86: Pass in pt_regs pointer for syscalls that need it References: <1234277507-4987-1-git-send-email-brgerst@gmail.com> <1234277507-4987-3-git-send-email-brgerst@gmail.com> <4992812B.1050800@kernel.org> <73c1f2160902110631j68e58202h3e49288cfe613d66@mail.gmail.com> <4992E396.6000205@kernel.org> <4992E551.4060901@gmail.com> <73c1f2160902110659i776e1d89qc23d89363881572e@mail.gmail.com> <4992E92C.5000000@gmail.com> <73c1f2160902110710u77a563bftf09c460fab6f9136@mail.gmail.com> In-Reply-To: <73c1f2160902110710u77a563bftf09c460fab6f9136@mail.gmail.com> X-Enigmail-Version: 0.95.7 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Brian Gerst wrote: > x86-64 doesn't have the tail-call problem because it doesn't use the > pt_regs on stack trick for syscall args. All the args are passed in > registers. Yeah, I was saying that we can do about the same thing on x86_32 by passing in pointer to pt_regs and defining proper syscall wrappers. It will cost a bit of performance by increasing register pressure tho. -- tejun