From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 451A2282F29; Fri, 13 Mar 2026 09:04:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=90.155.92.199 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773392654; cv=none; b=ml1wPMCaIl4a9DA/tCVx6vK58QfkV2O846pqbxEyucCmb8eCDbCC2j+9HNN5eEEkNCf2eo/T6S4P9YtaoduKvrAcoiVu9IlLo5Q48Lzf3a/WBW+A4okMi/Wvc+g/Njo6KARk/1nZIM3o/lxxjIBSVRarxL1/BsEevFztXGJnfKE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773392654; c=relaxed/simple; bh=c+OSf/n7cv+nTPecTTUs7Q+tlQmVPSGxqpjCqI33uvs=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=e0+HILwFsfdNEIJhlmlLl3D7GOvSiRZMk/p+76hyqVUS5ugYK4kcoyTlS6BlnCTKR8djCWzvPDy+cqswrPr2e6ApurmP7EJskDhDa5wDEinPVADycvt4an51fWXZyxyWFx9mR/Z2jhDGwvsU3lb20FyYmijVRDrirzC6yr0QKck= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=infradead.org; spf=none smtp.mailfrom=infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=VZFOvesL; arc=none smtp.client-ip=90.155.92.199 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="VZFOvesL" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=d1in1LivxTygelDpc3fvkaUshdJL6JIxUbijl840uK4=; b=VZFOvesLG6nkg1kFS3VbjoA+Wz T5YsDZWXmHoe460Sg+5KJ3KO5MVFk/DBzkio4BAcw3ZHm6bsUQUqwISJYcRFbyLVJ0Z4nkGsGN1nj Q/LP/C6Ndh0gaG3e0vwidAnwQYJ5tR+m/v6WTDG9ut1eFqTcIPQs4z9/YMQ3wAAol2Z/mwosgBZXu HpmWaJt3kVN61cRcTkpTW+S/0gVzGPudPsZuGXUX27gqZg1WEp98VOLRcs7A+dwZCpU18eqmgdU+o A7GvpoETAaC12ale4lP0kYur2IPkVVzfjBc7kGoVK02nRQ7IH1nAUr2bsiCGcU2/GLJV7BZgzNx2D 5L1ZcYxA==; Received: from 77-249-17-252.cable.dynamic.v4.ziggo.nl ([77.249.17.252] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.98.2 #2 (Red Hat Linux)) id 1w0yRB-00000002v19-1KHi; Fri, 13 Mar 2026 09:04:05 +0000 Received: by noisy.programming.kicks-ass.net (Postfix, from userid 1000) id C985A300FB6; Fri, 13 Mar 2026 10:04:04 +0100 (CET) Date: Fri, 13 Mar 2026 10:04:04 +0100 From: Peter Zijlstra To: Wander Lairson Costa Cc: Ingo Molnar , Juri Lelli , Vincent Guittot , Dietmar Eggemann , Steven Rostedt , Ben Segall , Mel Gorman , Valentin Schneider , Masami Hiramatsu , Mathieu Desnoyers , Andrew Morton , "open list:SCHEDULER" , "open list:TRACING" , acme@kernel.org, williams@redhat.com, gmonaco@redhat.com Subject: Re: [PATCH v3 1/4] tracing/preemptirq: Optimize preempt_disable/enable() tracepoint overhead Message-ID: <20260313090404.GK606826@noisy.programming.kicks-ass.net> References: <20260311125021.197638-1-wander@redhat.com> <20260311125021.197638-2-wander@redhat.com> <20260311193503.GS606826@noisy.programming.kicks-ass.net> Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Thu, Mar 12, 2026 at 02:19:15PM -0300, Wander Lairson Costa wrote: > > That's significant bloat, for really very little gain. Realistically > > nobody is going to need these. > > > > Of course, I can't speak for others, but more than once I debugged issues > that those tracepoints had made my life far easier. Those cases convinced > me that such a feature would be worth it. But if you don't see > value and will reject the patches no matter what, nothing can be done, > and I will have to accept defeat. If distros are going to enable this, I suppose I'm not going to stop this. But I do very much worry about the general bloat of things, there are a *LOT* of preempt_{dis,en}able() sites.