Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S966418AbdIYXeq (ORCPT ); Mon, 25 Sep 2017 19:34:46 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:60042 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S966206AbdIYXeo (ORCPT ); Mon, 25 Sep 2017 19:34:44 -0400 Date: Mon, 25 Sep 2017 16:34:43 -0700 From: Andrew Morton To: Alexei Starovoitov Cc: Laurent Dufour , Paul McKenney , Peter Zijlstra , kirill@shutemov.name, Andi Kleen , Michal Hocko , dave@stgolabs.net, Jan Kara , Matthew Wilcox , Benjamin Herrenschmidt , Michael Ellerman , Paul Mackerras , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , Will Deacon , Sergey Senozhatsky , "linux-kernel@vger.kernel.org" , linux-mm , haren@linux.vnet.ibm.com, Anshuman Khandual , npiggin@gmail.com, bsingharora@gmail.com, Tim Chen , linuxppc-dev@lists.ozlabs.org, "x86@kernel.org" Subject: Re: [PATCH v3 00/20] Speculative page faults Message-Id: <20170925163443.260d6092160ec704e2b04653@linux-foundation.org> In-Reply-To: References: X-Mailer: Sylpheed 3.4.1 (GTK+ 2.24.23; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1359 Lines: 32 On Mon, 25 Sep 2017 09:27:43 -0700 Alexei Starovoitov wrote: > On Mon, Sep 18, 2017 at 12:15 AM, Laurent Dufour > wrote: > > Despite the unprovable lockdep warning raised by Sergey, I didn't get any > > feedback on this series. > > > > Is there a chance to get it moved upstream ? > > what is the status ? > We're eagerly looking forward for this set to land, > since we have several use cases for tracing that > will build on top of this set as discussed at Plumbers. There has been sadly little review and testing so far :( I'll be taking a close look at it all over the next couple of weeks. One terribly important thing (especially for a patchset this large and intrusive) is the rationale for merging it: the justification, usually in the form of end-user benefit. Laurent's [0/n] provides some nice-looking performance benefits for workloads which are chosen to show performance benefits(!) but, alas, no quantitative testing results for workloads which we may suspect will be harmed by the changes(?). Even things as simple as impact upon single-threaded pagefault-intensive workloads and its effect upon CONFIG_SMP=n .text size? If you have additional usecases then please, spell them out for us in full detail so we can better understand the benefits which this patchset provides.