From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-lj1-f197.google.com (mail-lj1-f197.google.com [209.85.208.197]) by kanga.kvack.org (Postfix) with ESMTP id 870DA6B000A for ; Sat, 6 Oct 2018 01:11:20 -0400 (EDT) Received: by mail-lj1-f197.google.com with SMTP id r20-v6so3396873ljj.1 for ; Fri, 05 Oct 2018 22:11:20 -0700 (PDT) Received: from mail-sor-f65.google.com (mail-sor-f65.google.com. [209.85.220.65]) by mx.google.com with SMTPS id d132-v6sor3489734lfd.50.2018.10.05.22.11.18 for (Google Transport Security); Fri, 05 Oct 2018 22:11:18 -0700 (PDT) MIME-Version: 1.0 References: <20181003185854.GA1174@jordon-HP-15-Notebook-PC> <20181003200003.GA9965@bombadil.infradead.org> <20181003221444.GZ30658@n2100.armlinux.org.uk> <20181004123400.GC30658@n2100.armlinux.org.uk> <20181004181736.GB20842@bombadil.infradead.org> In-Reply-To: From: Souptick Joarder Date: Sat, 6 Oct 2018 10:44:26 +0530 Message-ID: Subject: Re: [PATCH v2] mm: Introduce new function vm_insert_kmem_page Content-Type: text/plain; charset="UTF-8" Sender: owner-linux-mm@kvack.org List-ID: To: Miguel Ojeda Cc: Matthew Wilcox , Russell King - ARM Linux , robin@protonic.nl, stefanr@s5r6.in-berlin.de, hjc@rock-chips.com, Heiko Stuebner , airlied@linux.ie, robin.murphy@arm.com, iamjoonsoo.kim@lge.com, Andrew Morton , Marek Szyprowski , Kees Cook , treding@nvidia.com, Michal Hocko , Dan Williams , "Kirill A. Shutemov" , Mark Rutland , aryabinin@virtuozzo.com, Dmitry Vyukov , Kate Stewart , tchibo@google.com, riel@redhat.com, Minchan Kim , Peter Zijlstra , "Huang, Ying" , ak@linux.intel.com, rppt@linux.vnet.ibm.com, linux@dominikbrodowski.net, Arnd Bergmann , cpandya@codeaurora.org, hannes@cmpxchg.org, Joe Perches , mcgrof@kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux1394-devel@lists.sourceforge.net, dri-devel@lists.freedesktop.org, linux-rockchip@lists.infradead.org, Linux-MM On Fri, Oct 5, 2018 at 11:39 PM Miguel Ojeda wrote: > > On Fri, Oct 5, 2018 at 2:11 PM Souptick Joarder wrote: > > > > On Fri, Oct 5, 2018 at 4:19 PM Miguel Ojeda > > wrote: > > > > > > 1. Introduce the vmf_* API > > > 2. Change all PF-users users to that (leaving all non-PF ones > > > untouched!) -- if this is too big, you can split this patch into > > > several patches, one per subsystem, etc. > > > > We are done with step 2. All the PF-users are converted to use > > vmf_insert_page. ( Ref - linux-next-20181005) > > They are not supposed to be "steps". You did it with 70+ commits (!!) > over the course of several months. Why a tree wasn't created, stuff > developed there, and when done, submitted it for review? Because we already have a plan for entire vm_fault_t migration and the * instruction * was to send one patch per driver. > > > > > > > Otherwise, if you want to pursue Matthew's idea: > > > > > > 4. Introduce the vm_insert_range (possibly leveraging > > > vm_insert_page, or not; you have to see what is best). > > > 5. Replace those callers that can take advantage of vm_insert_range > > > 6. Remove vm_insert_page and replace callers with vm_insert_range > > > (only if it is not worth to keep vm_insert_range, again justifying it > > > *on its own merits*) > > > > Step 4 to 6, going to do it. It is part of plan now :-) > > > > Fine, but you haven't answered to the other parts of my email: you > don't explain why you choose one alternative over the others, you > simply keep changing the approach. We are going in circles here. That you want to convert vm_insert_page to vmf_insert_page for the PF case is fine and understood. However, you don't *need* to introduce a new name for the remaining non-PF cases if the function is going to be the exact same thing as before. You say "The final goal is to remove vm_insert_page", but you haven't justified *why* you need to remove that name. I think I have given that answer. If we don't remove vm_insert_page, future #PF caller will have option to use it. But those should be restricted. How are we going to restrict vm_insert_page in one half of kernel when other half is still using it ?? Is there any way ? ( I don't know)