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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