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=-7.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=unavailable 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 3EF6ACA9ECF for ; Thu, 31 Oct 2019 13:00:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1EE252080F for ; Thu, 31 Oct 2019 13:00:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727002AbfJaNAa (ORCPT ); Thu, 31 Oct 2019 09:00:30 -0400 Received: from foss.arm.com ([217.140.110.172]:48184 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726462AbfJaNA3 (ORCPT ); Thu, 31 Oct 2019 09:00:29 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id A2D1B1FB; Thu, 31 Oct 2019 06:00:28 -0700 (PDT) Received: from blommer (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id DD8B03F71E; Thu, 31 Oct 2019 06:00:24 -0700 (PDT) Date: Thu, 31 Oct 2019 13:00:22 +0000 From: Mark Rutland To: Torsten Duwe Cc: linux-arm-kernel@lists.infradead.org, Jessica Yu , Helge Deller , "James E.J. Bottomley" , linux-kernel@vger.kernel.org, amit.kachhap@arm.com, catalin.marinas@arm.com, james.morse@arm.com, jpoimboe@redhat.com, jthierry@redhat.com, linux-parisc@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, rostedt@goodmis.org, svens@stackframe.org, takahiro.akashi@linaro.org, will@kernel.org Subject: Re: [PATCHv2 2/8] module/ftrace: handle patchable-function-entry Message-ID: <20191031130022.GB3477@blommer> References: <20191029165832.33606-1-mark.rutland@arm.com> <20191029165832.33606-3-mark.rutland@arm.com> <20191030150302.GA965@suse.de> <20191031090231.GA3340@blommer> <20191031114223.GA11684@suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20191031114223.GA11684@suse.de> User-Agent: Mutt/1.11.1+11 (2f07cb52) (2018-12-01) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Oct 31, 2019 at 12:42:23PM +0100, Torsten Duwe wrote: > On Thu, Oct 31, 2019 at 09:02:32AM +0000, Mark Rutland wrote: > > I agree that the CC_USING_PATCHABLE_FUNCTION_ENTRY ifdeffery could be > > simplified, and that it would be nice to consistently use > > FTRACE_CALLSITE_SECTION if we can. However, the generic linker script doesn't > > include anything, and I don't see a good location for that to live. > > > > What I could do is add an explicit comment: > > > > /* > > * The ftrace call sites are logged to a section whose name depends on the > > * compiler option used. A given kernel image will only use one, AKA > > * FTRACE_CALLSITE_SECTION. We capture all of them here to avoid header > > * dependencies. > > */ > > #define MCOUNT_REC() \ > > . = ALIGN(8); \ > > __start_mcount_loc = .; \ > > KEEP(*(__patchable_function_entries)) \ > > KEEP(*(__mcount_loc)) \ > > __stop_mcount_loc = .; > > > > ... which should make the dependency clear. Does that sound good to you? > > Beautiful. I just didn't want to miss the opportunity to have this cleaned > up as well, and deemed this patch "closest" because of the definition of > FTRACE_CALLSITE_SECTION. Put it where you see it fit best. Sure. I've folded the above into this patch, and pushed out an updated branch: https://git.kernel.org/pub/scm/linux/kernel/git/mark/linux.git/log/?h=arm64/ftrace-with-regs Thanks, Mark.