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=-6.3 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 43054C4363C for ; Mon, 5 Oct 2020 00:18:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E8A29206C3 for ; Mon, 5 Oct 2020 00:18:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1601857139; bh=0PRbYKqOJWD7i8Tsch9Sw20KniYBGQmRVsBXM4bljJ8=; h=Date:From:To:Cc:Subject:Reply-To:References:In-Reply-To:List-ID: From; b=TisqIdCqWacL5WnO9ut2ThzzZdHm6P6wJCIf3jV8NPV32hfEeyRNbDA/ARzoQSi7N 0AnmJbonerSsbLDMoYn4H+F7H5iU0PUwNZi8N9iPsvP5IiJQgD/YgLfcLxtA/Xx7DT 6J2w718GEniO3wX6YNY9cbKuKz4Q8xrUYuQX56bM= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725865AbgJEAS5 (ORCPT ); Sun, 4 Oct 2020 20:18:57 -0400 Received: from mail.kernel.org ([198.145.29.99]:32814 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725836AbgJEAS5 (ORCPT ); Sun, 4 Oct 2020 20:18:57 -0400 Received: from paulmck-ThinkPad-P72.home (50-39-104-11.bvtn.or.frontiernet.net [50.39.104.11]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id B2C55206B6; Mon, 5 Oct 2020 00:18:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1601857136; bh=0PRbYKqOJWD7i8Tsch9Sw20KniYBGQmRVsBXM4bljJ8=; h=Date:From:To:Cc:Subject:Reply-To:References:In-Reply-To:From; b=SsS0uTOZ30Z5RUulBZ72nJTsbLZbrSL+vci59Wk/Ht4Z0Shk8QjPrYk7fkiWkFGuY O+5OXulMlOBBuuQZe/vANH6A/LTiRzV7qE2L6AU2ifXp/riwZhPjM9WiQknm71lm4k OOKfou8pHvXTDlFNTMF/cn25s/46N/to9mVbIw4I= Received: by paulmck-ThinkPad-P72.home (Postfix, from userid 1000) id 74A4035225F2; Sun, 4 Oct 2020 17:18:56 -0700 (PDT) Date: Sun, 4 Oct 2020 17:18:56 -0700 From: "Paul E. McKenney" To: Steven Rostedt Cc: Peter Zijlstra , linux-kernel@vger.kernel.org, Thomas Gleixner , Ingo Molnar , kim.phillips@amd.com Subject: Re: [PATCH] rcu,ftrace: Fix ftrace recursion Message-ID: <20201005001856.GT29330@paulmck-ThinkPad-P72> Reply-To: paulmck@kernel.org References: <20200929113340.GN2628@hirez.programming.kicks-ass.net> <20200929103620.06762622@gandalf.local.home> <20200929144105.GU29330@paulmck-ThinkPad-P72> <20200929105416.757c47f0@gandalf.local.home> <20200929165640.GV29330@paulmck-ThinkPad-P72> <20200929130449.12c474a5@gandalf.local.home> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200929130449.12c474a5@gandalf.local.home> User-Agent: Mutt/1.9.4 (2018-02-28) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Sep 29, 2020 at 01:04:49PM -0400, Steven Rostedt wrote: > On Tue, 29 Sep 2020 09:56:40 -0700 > "Paul E. McKenney" wrote: > > > > Well, I think we should actually apply both, but the comment needs to be > > > updated, as it will no longer be outside recursion. And the comment is > > > wrong now as well, as its only outside recursion protection for the > > > assist_func(). > > > > > > But it does prevent it from being always called for perf. > > > > > > * Make notrace because it can be called by the internal functions of > > > * ftrace, and making this notrace removes unnecessary recursion calls. > > > > Fair enough. ;-) > > > > If I don't hear otherwise by late today (Tuesday), Pacific Time, I will > > update the comment and pull it into -rcu. If you guys have some other > > route to mainline in mind, you have my Reviewed-by. Either way, just > > let me know. > > I'm currently testing the recursion fix and will push that to Linus when > done. But you can take the comment update through your tree. > > Peter, are you OK if Paul changes your comment to what I suggested? Hearing no objections, I have queued the patch with the comment updated as suggested by Steven. Thank you all! Thanx, Paul