From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 42EDCCD3423 for ; Fri, 1 May 2026 16:06:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=HCOnYxAIgiWvR0Bg9Z3oQP7NtLB+AbBygf9mhxuV9oQ=; b=ElkryYkYPEE2kAzwdFTkXURrwZ YloXDgRfeVrM/7P37R/vemv9TExf2wV5rMfhmH0eo1R3BzZbkKZLNqlf1OCgGOr13aBbb8eBTDERM +zg7emF4OXoJ9qnv5etTX2svHDAlXq11sZgClfcL7S6+3K95qB4lR3bFJ2obe2MeSM7slmRPqg/1n KRiaugpwYpWicccozoqx04yDih318zokmZImgKMcfX6+ZQTiiFWc7O8cE7Z+9BDsI0uJ507t16tRz cE482/1XUqhjH/+lV+uZWopQOWd6rSPSyq3gEpFl+VD/hysnSd8to/69t50PTf8zw/L5mhvYgpiLR jJhHJdHw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1wIqNb-00000007O2S-3Opi; Fri, 01 May 2026 16:06:15 +0000 Received: from casper.infradead.org ([2001:8b0:10b:1236::1]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1wIqNa-00000007O2G-0zl8; Fri, 01 May 2026 16:06:14 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=HCOnYxAIgiWvR0Bg9Z3oQP7NtLB+AbBygf9mhxuV9oQ=; b=WFSklIdwMHQLNKo0hSt8FUEdor 8PWAceSimwETsGI72z85Zv4wA/tsNlycLa8f6sQG/Aw6w8RnhXi0Af5mjum18LwybDyAvb1+Uxh9f Eq5T7ug+O10pWFjftTfOmniisY01PyMq7+2peSvdamJ+AAvHZRIQTazUoIUXsplGALDIdW/42jR8p U9uUO/7PltvaGp/EEhx55GmxP2PijjP4N8jL7/SdhnE0m0apJTc1yrnAE6WrXuehMZUnK54FJ0YvF M5qMff6H54NLzO+TN+U51R/JiQDmY0k5rW4FXREurwavyb9AebilT1ieN2HbK2yQvGHgLvA2FHU0e rgYRe6xw==; 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-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org 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).