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Received: from willy by casper.infradead.org with local (Exim 4.98.2 #2 (Red Hat Linux)) id 1wIqNP-000000091GR-0gTr; Fri, 01 May 2026 16:06:03 +0000 Date: Fri, 1 May 2026 17:06:02 +0100 From: Matthew Wilcox To: Lorenzo Stoakes Cc: "Barry Song (Xiaomi)" , akpm@linux-foundation.org, linux-mm@kvack.org, david@kernel.org, liam@infradead.org, vbabka@kernel.org, rppt@kernel.org, surenb@google.com, mhocko@suse.com, jack@suse.cz, pfalcato@suse.de, wanglian@kylinos.cn, chentao@kylinos.cn, lianux.mm@gmail.com, kunwu.chan@gmail.com, liyangouwen1@oppo.com, chrisl@kernel.org, kasong@tencent.com, shikemeng@huaweicloud.com, nphamcs@gmail.com, bhe@redhat.com, youngjun.park@lge.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, loongarch@lists.linux.dev, linuxppc-dev@lists.ozlabs.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org Subject: Re: [PATCH v2 0/5] mm: reduce mmap_lock contention and improve page fault performance Message-ID: References: <20260430040427.4672-1-baohua@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspamd-Server: rspam11 X-Rspamd-Queue-Id: 140974001A X-Stat-Signature: qcwchazmqjfoz9h8txbj3x4ztez9pif8 X-Rspam-User: X-HE-Tag: 1777651574-265220 X-HE-Meta: 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 wi3q74Nt uqMCI2dhG0uBw1hdL8q0ePYnA0hLgXPZIUQbRv3GAX6D5ZPAW7bzDf7vYYEC4bdwPFHt+uzNOp5dSg7Gx3ivVs0KeKSMuuYhxyHGQ4nCtf2C72k6us0vrN6q69Wbg0aL3ppGC/jukqyQ3/2JhhytX7BcS7rGX7B3o7KxarGiV5h5fkQ4Z/Wkfbynp2rFv8nYHoM7ev4A3qrFTZ1gzYNajE71n4D3+xGUHo8tl6j2iiCf4Ulsictj0LU28qYkWLuwFxEGo6wmUFGmR20qHU4K2sE4FuepzUBWCF/tMAVRTa3CJ77kKTe3q3aMnIduq2AY6T+rmhoM9zZivTy1AZH7DfgvLV1j4geAhcC+ghvFMuAUH3qN7namLYSVtcQ== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Fri, May 01, 2026 at 04:52:12PM +0100, Lorenzo Stoakes wrote: > After a brief eyeball I share Matthew's assessment, I really don't like this > series, it's piling on complexity for what seem like niche cases. I don't think they're niche cases ... I think it's a real problem. While our current code performs better for this workload than the pre-vma-lock code did, it doesn't perform as well as it could. > We already have enough weirdness in fault code honestly. > > Let's maybe discuss at LSF if you're attending? Not only is he attending, there's a topic scheduled (currently 10:30 on Wednesday).