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imf22.hostedemail.com; dkim=none; dmarc=none; spf=pass (imf22.hostedemail.com: domain of byungchul@sk.com designates 166.125.252.92 as permitted sender) smtp.mailfrom=byungchul@sk.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1749455609; a=rsa-sha256; cv=none; b=I/cBjsBNupJqKfm3pXdTAx90WxHcTgnaN+pHFqNdZDB3SvfnZmnDptLZ8Pjxuwn0K5pyAR r2vSIfscxkO9tTvfmi7cHnrEEQ5qFZlQG20GRtTOeKolpxjNiJokHMEjFidpuzUJ8f9N03 53CMmJr9VwYvGovg4ApWsmmibP40MpI= X-AuditID: a67dfc5b-669ff7000002311f-da-684692f6e63c Date: Mon, 9 Jun 2025 16:53:21 +0900 From: Byungchul Park To: Mina Almasry Cc: willy@infradead.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, kernel_team@skhynix.com, kuba@kernel.org, ilias.apalodimas@linaro.org, harry.yoo@oracle.com, hawk@kernel.org, akpm@linux-foundation.org, davem@davemloft.net, john.fastabend@gmail.com, andrew+netdev@lunn.ch, asml.silence@gmail.com, toke@redhat.com, tariqt@nvidia.com, edumazet@google.com, pabeni@redhat.com, saeedm@nvidia.com, leon@kernel.org, ast@kernel.org, daniel@iogearbox.net, david@redhat.com, lorenzo.stoakes@oracle.com, Liam.Howlett@oracle.com, vbabka@suse.cz, rppt@kernel.org, surenb@google.com, mhocko@suse.com, horms@kernel.org, linux-rdma@vger.kernel.org, bpf@vger.kernel.org, vishal.moola@gmail.com, netdev@vger.kernel.org Subject: Re: [RFC v4 00/18] Split netmem from struct page Message-ID: <20250609075321.GA59170@system.software.com> References: <20250604025246.61616-1-byungchul@sk.com> <20250604032319.GA69870@system.software.com> <20250609042255.GA43325@system.software.com> MIME-Version: 1.0 Content-Type: text/plain; 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This patchset does > > > > that for netmem which is used for page pools. > > > > > > > > Matthew Wilcox tried and stopped the same work, you can see in: > > > > > > > > https://lore.kernel.org/linux-mm/20230111042214.907030-1-willy@infradead.org/ > > > > > > > > Mina Almasry already has done a lot fo prerequisite works by luck. I > > > > stacked my patches on the top of his work e.i. netmem. > > > > > > > > I focused on removing the page pool members in struct page this time, > > > > not moving the allocation code of page pool from net to mm. It can be > > > > done later if needed. > > > > > > > > The final patch removing the page pool fields will be submitted once > > > > all the converting work of page to netmem are done: > > > > > > > > 1. converting of libeth_fqe by Tony Nguyen. > > > > 2. converting of mlx5 by Tariq Toukan. > > > > 3. converting of prueth_swdata (on me). > > > > 4. converting of freescale driver (on me). > > > > > > > > For our discussion, I'm sharing what the final patch looks like the > > > > following. > > > > > > To Willy and Mina, > > > > > > I believe this version might be the final version. Please check the > > > direction if it's going as you meant so as to go ahead convinced. > > > > > > As I mentioned above, the final patch should be submitted later once all > > > the required works on drivers are done, but you can check what it looks > > > like, in the following embedded patch in this cover letter. > > > > > > > We need this tested with at least 1 of devmem TCP and io_uring zc to > > make sure the net_iov stuff isn't broken (I'll get to that when I have > > time). > > > > And we need page_pool benchmark numbers before/after this series, > > please run those yourself, if at all possible: > > I'm trying but it keeps conflicting on several steps.. Please share a > better manual. > > Byungchul > > > https://lore.kernel.org/netdev/20250525034354.258247-1-almasrymina@google.com/ I will try this guide again with some adjusted.. Thanks anyway. Byungchul > > > > This series adds a bunch of netmem/page casts. I expect them not to > > affect fast-path perf, but making sure would be nice. > > > > -- > > Thanks, > > Mina