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 89BA46B0006 for ; Tue, 23 Oct 2018 08:14:47 -0400 (EDT) Received: by mail-lj1-f197.google.com with SMTP id h70-v6so461078ljf.14 for ; Tue, 23 Oct 2018 05:14:47 -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 o24-v6sor721026ljj.4.2018.10.23.05.14.45 for (Google Transport Security); Tue, 23 Oct 2018 05:14:45 -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: Tue, 23 Oct 2018 17:44:32 +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 Sat, Oct 6, 2018 at 4:19 PM Miguel Ojeda wrote: > > On Sat, Oct 6, 2018 at 7:11 AM Souptick Joarder wrote: > > > > On Fri, Oct 5, 2018 at 11:39 PM Miguel Ojeda > > wrote: > > > 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. > > The instruction? Sorry for the delayed response. Instruction from Matthew Wilcox who is supervising the entire vm_fault_t migration work :-) > > > > > > > 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) > > Ah, so that is what you are concerned about: future misuses. Well, I > don't really see the problem. There are only ~18 calls to > vm_insert_page() in the entire kernel: checking if people is using it > properly for a while should be easy. As long as the new behavior is > documented properly, it should be fine. If you are really concerned > about mistakes being made, then fine, we can rename it as I suggested. > > Now, the new vm_insert_range() is another topic. It simplifies a few > of the callers and buys us the rename at the same time, so I am also > OK with it. > > As you see, I am not against the changes -- it is just that they > should clearly justified. :-) It wasn't clear what your problem with > the current vm_insert_page() is. > > Cheers, > Miguel