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=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS 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 68ECAC0044C for ; Wed, 7 Nov 2018 18:53:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 39C582081D for ; Wed, 7 Nov 2018 18:53:36 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 39C582081D Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=deltatee.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729553AbeKHEZN (ORCPT ); Wed, 7 Nov 2018 23:25:13 -0500 Received: from ale.deltatee.com ([207.54.116.67]:48944 "EHLO ale.deltatee.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726938AbeKHEZN (ORCPT ); Wed, 7 Nov 2018 23:25:13 -0500 Received: from guinness.priv.deltatee.com ([172.16.1.162]) by ale.deltatee.com with esmtp (Exim 4.89) (envelope-from ) id 1gKSwu-0004PD-ET; Wed, 07 Nov 2018 11:53:09 -0700 To: Nadav Amit , Ingo Molnar Cc: LKML , X86 ML , Sam Ravnborg , Michal Marek , Thomas Gleixner , "H. Peter Anvin" , Linux Kbuild mailing list , Stephen Bates References: <20181003213100.189959-1-namit@vmware.com> <20181003213100.189959-3-namit@vmware.com> <89262174-6f15-6116-e67f-436f7c1bfe99@deltatee.com> <6651971B-E3AB-4CDD-868C-2338593F7D83@vmware.com> From: Logan Gunthorpe Message-ID: Date: Wed, 7 Nov 2018 11:53:02 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.2.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-CA Content-Transfer-Encoding: 7bit X-SA-Exim-Connect-IP: 172.16.1.162 X-SA-Exim-Rcpt-To: sbates@raithlin.com, linux-kbuild@vger.kernel.org, hpa@zytor.com, tglx@linutronix.de, michal.lkml@markovi.net, sam@ravnborg.org, x86@kernel.org, linux-kernel@vger.kernel.org, mingo@redhat.com, namit@vmware.com X-SA-Exim-Mail-From: logang@deltatee.com Subject: Re: [PATCH v9 02/10] Makefile: Prepare for using macros for inline asm X-SA-Exim-Version: 4.2.1 (built Tue, 02 Aug 2016 21:08:31 +0000) X-SA-Exim-Scanned: Yes (on ale.deltatee.com) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2018-11-07 11:01 a.m., Nadav Amit wrote: > Ideas? Do people care about it? Just spit balling, but is there a reason we didn't just put the macros for inline assembly directly in the header? Something like this: asm(".macro ANNOTATE_UNREACHABLE counter:req\n\t" "\\counter:\n\t" ".pushsection .discard.unreachable\n\t" ".long \\counter\\()b -.\n\t" ".popsection\n\t" ".endm\n"); #define annotate_unreachable() ({ \ asm volatile("ANNOTATE_UNREACHABLE counter=%c0" \ : : "i" (__COUNTER__)); \ }) It does mean the macros won't be usable in non-inline assembly, without duplicating them, but do we care about that? I would have expected people compiling the kernel with distcc to be fairly common -- it certainly speeds up my kernel compiles quite significantly and thus saves me a lot of time. Logan