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b=OX2L1x4xFIxbScfPDUbir6mmS+xdX9NmUYzJR0EJkE7ri86qbaeUTkDb4jWI5oeb+ aN4JbRR+N5UIrCNNa22w2pCZ2JSMSHoSZwNy2T2qFiVEenmDxH9tkupv+ZDyGU2ObI 654hr8gYpcXDtcmeRIPh1KdMIPoWk95vpdUy3GSPXi4IHKF8A7wxn55TDFMfm9T3X7 2RVfuwK5n/jkaekIr44u2S02mSaPb7gcycVdlcOtlmx86ngcN1rcmImzOHzRA44jyl l2G+a79TnBeaUy0DKnFo0u2dmfaqSvsLz/R2tzsXHpnuJk6XOz3vggn1h43+SNrKA+ 0+Ne8WhoVmpcw== Date: Fri, 1 May 2026 18:09:30 +0100 From: Lorenzo Stoakes To: Matthew Wilcox 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: rspam09 X-Rspamd-Queue-Id: 4768420018 X-Rspam-User: X-Stat-Signature: g7s5sxi8kai1rw7rkt5iib9i85ceezt9 X-HE-Tag: 1777655381-209414 X-HE-Meta: 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 5/qRih6b AWMoDSqPdUpBT5R6q7NMQZuPmS001IGLMQ0xX6L6jJRKsi3AC66VEMlgsywtur3G+U7BpgHY3/8FO2y6CbqG5PN3oq0+1eGtxM8Il1vxt7fV+20Pm/8uaMrOJuWBrNseYbypDFkEE9F+TC8UpGdK5nAGJ9lMay8megXAXNHVe7oZCdqZYzKdoqdz8TLFX3/ubxeb1v4IVHb2IAGSv44q0DF+WOkksSuY1e9Bu+vtw6C3BF/6dz/uQc5BdhxOqc5OnZ8dnv/QIbuocq8Kj6+OU05bO4NN4nNTEMhCehR1S5++jr0w8LUb06zMYoTOrTTb5PvQzmmnTEZrWwXueZMzu6kQdlzqh3yQvIAH6V0k/XuXdaHvDZ1HPffgc6A== 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 05:06:02PM +0100, Matthew Wilcox wrote: > 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). Well then, let's revisit this in person in Zagreb :) Cheers, Lorenzo