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[96.255.20.138]) by smtp.gmail.com with ESMTPSA id af79cd13be357-89f25798afesm626595985a.37.2025.10.27.09.38.49 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 27 Oct 2025 09:38:50 -0700 (PDT) Date: Mon, 27 Oct 2025 12:38:48 -0400 From: Gregory Price To: Lorenzo Stoakes Cc: Jason Gunthorpe , Andrew Morton , Christian Borntraeger , Janosch Frank , Claudio Imbrenda , David Hildenbrand , Alexander Gordeev , Gerald Schaefer , Heiko Carstens , Vasily Gorbik , Sven Schnelle , Zi Yan , Baolin Wang , "Liam R . Howlett" , Nico Pache , Ryan Roberts , Dev Jain , Barry Song , Lance Yang , Kemeng Shi , Kairui Song , Nhat Pham , Baoquan He , Chris Li , Peter Xu , Matthew Wilcox , Leon Romanovsky , Muchun Song , Oscar Salvador , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Jann Horn , Matthew Brost , Joshua Hahn , Rakie Kim , Byungchul Park , Ying Huang , Alistair Popple , Pedro Falcato , Pasha Tatashin , Rik van Riel , Harry Yoo , kvm@vger.kernel.org, linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [RFC PATCH 05/12] fs/proc/task_mmu: refactor pagemap_pmd_range() Message-ID: References: <2ce1da8c64bf2f831938d711b047b2eba0fa9f32.1761288179.git.lorenzo.stoakes@oracle.com> <76348b1f-2626-4010-8269-edd74a936982@lucifer.local> <3f3e5582-d707-41d0-99a7-4e9c25f1224d@lucifer.local> <20251027161146.GG760669@ziepe.ca> <27a5ea4e-155c-40d1-87d7-e27e98b4871d@lucifer.local> Precedence: bulk X-Mailing-List: linux-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: <27a5ea4e-155c-40d1-87d7-e27e98b4871d@lucifer.local> On Mon, Oct 27, 2025 at 04:26:54PM +0000, Lorenzo Stoakes wrote: > On Mon, Oct 27, 2025 at 01:11:46PM -0300, Jason Gunthorpe wrote: > > On Fri, Oct 24, 2025 at 04:37:18PM -0400, Gregory Price wrote: > > > On Fri, Oct 24, 2025 at 09:15:59PM +0100, Lorenzo Stoakes wrote: > > > > On Fri, Oct 24, 2025 at 03:12:08PM -0400, Gregory Price wrote: > > > > > > > > So maybe actually that isn't too bad of an idea... > > > > > > > > Could also be > > > > > > > > nonpresent_or_swap_t but that's kinda icky... > > > > > > clearly we need: > > > > > > union { > > > swp_entry_t swap; > > > nonpresent_entry_t np; > > > pony_entry_t pony; > > > plum_emtry_t beer; > > > } leaf_entry_t; > > I think Greg meant this as a joke [correct me if wrong] :) that was my > impression anyway (see original end of email...) > > I like leaf_entry_t name-wise. > > I don't love the union. > The union was definitely a joke - see `plum_entry_t beer` There definitely shouldn't be enough extensions to warrant a union here, that seems like negative value. leaf_entry_t naming replacing swp_entry_t seems reasonable since that's basically all swp_entry_t is in its current form - even according to the this set's cover letter: ``` There's an established convention in the kernel that we treat leaf page tables (so far at the PTE, PMD level) as containing 'swap entries' should they be neither empty (i.e. p**_none() evaluating true) nor present (i.e. p**_present() evaluating true). ``` ~Gregory