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=-5.2 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 78401CA9EB5 for ; Mon, 4 Nov 2019 13:38:45 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 49DF12184C for ; Mon, 4 Nov 2019 13:38:45 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="if08WcTU" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 49DF12184C Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=rbLK9SeBXCMZTBWcwitettlFw3BJOZBTtxR7kblQypc=; b=if08WcTU8LrFHM yrUmWnAsFbgdQS0z5LmG8uvxPBKzQmIJR3zqoHWl+DVPkBFsbgx2x13mUdUpVCW64Hh7m1uGCSIYv 2jDLfxcZDb4Z9fiyQQeKu7+XKYPiElxyFtIGbBrMmE3rhz5BidyPBOvL6Aw2mH8rQxb7WynTyqWqR TzV3Tzpz7CoYZi+IvlVnexSmzbjEpltsrzKjV0ljvIDPzLrQhyFSN4xyi7oQ40uRpoOPgycfn8dVh I3CC48jyTDTY1Ht34J+s77vKF4QfKUCyS2NnqZRaIGadocHV3snGfGthPF2pzI15NqHP8LXIUc5Zm O5yL5GvtUqav6l2uv7fw==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1iRcZA-0004XD-PF; Mon, 04 Nov 2019 13:38:44 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1iRcZ7-0004WR-Nb for linux-arm-kernel@lists.infradead.org; Mon, 04 Nov 2019 13:38:43 +0000 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 97DD81FB; Mon, 4 Nov 2019 05:38:40 -0800 (PST) Received: from lakrids.cambridge.arm.com (usa-sjc-imap-foss1.foss.arm.com [10.121.207.14]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 5FE8D3F6C4; Mon, 4 Nov 2019 05:38:38 -0800 (PST) Date: Mon, 4 Nov 2019 13:38:36 +0000 From: Mark Rutland To: Steven Rostedt Subject: Re: [PATCHv2 1/8] ftrace: add ftrace_init_nop() Message-ID: <20191104133836.GF45140@lakrids.cambridge.arm.com> References: <20191029165832.33606-1-mark.rutland@arm.com> <20191029165832.33606-2-mark.rutland@arm.com> <20191104081620.732320a8@grimm.local.home> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20191104081620.732320a8@grimm.local.home> User-Agent: Mutt/1.11.1+11 (2f07cb52) (2018-12-01) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20191104_053841_812366_8EA83C82 X-CRM114-Status: GOOD ( 15.55 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: jthierry@redhat.com, linux-parisc@vger.kernel.org, peterz@infradead.org, catalin.marinas@arm.com, deller@gmx.de, jpoimboe@redhat.com, linux-kernel@vger.kernel.org, James.Bottomley@HansenPartnership.com, takahiro.akashi@linaro.org, will@kernel.org, mingo@redhat.com, james.morse@arm.com, jeyu@kernel.org, amit.kachhap@arm.com, svens@stackframe.org, duwe@suse.de, linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Mon, Nov 04, 2019 at 08:16:20AM -0500, Steven Rostedt wrote: > On Tue, 29 Oct 2019 16:58:25 +0000 > Mark Rutland wrote: > > > Architectures may need to perform special initialization of ftrace > > callsites, and today they do so by special-casing ftrace_make_nop() when > > the expected branch address is MCOUNT_ADDR. In some cases (e.g. for > > patchable-function-entry), we don't have an mcount-like symbol and don't > > want a synthetic MCOUNT_ADDR, but we may need to perform some > > initialization of callsites. > > > > To make it possible to separate initialization from runtime > > modification, and to handle cases without an mcount-like symbol, this > > patch adds an optional ftrace_init_nop() function that architectures can > > implement, which does not pass a branch address. > > > > Where an architecture does not provide ftrace_init_nop(), we will fall > > back to the existing behaviour of calling ftrace_make_nop() with > > MCOUNT_ADDR. > > > > At the same time, ftrace_code_disable() is renamed to > > ftrace_nop_initialize() to make it clearer that it is intended to > > intialize a callsite into a disabled state, and is not for disabling a > > callsite that has been runtime enabled. The kerneldoc description of rec > > arguments is updated to cover non-mcount callsites. > > > > Signed-off-by: Mark Rutland > > Reviewed-by: Ard Biesheuvel > > Cc: Ingo Molnar > > Cc: Steven Rostedt > > Reviewed-by: Steven Rostedt (VMware) Thanks! Just to check, are you happy if this were to go via the arm64 tree with the rest of the patches? Mark. _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel