From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794476380; b=uQNzfRdYhnK+yCgj0mB5ugnVWSCHDOHxErCQ9euUzpz8Oxm1frS6KA1MRHsukvBna6s2 GXpw6qV9oH+PV4F5+crbl3wbiYsX/6aq205YFIdWaDY3Y1S55HXmPKgZbkUs8XIcK95tS aeFJ3qPdqunA3tRsarNUAkwQyOCiwyQ/Ft1G3UWX2Qcukjt6ZNOn9xbgIWCKrbDgxPGeA vXST042zlSArB1+pDY+SQTtDoUX/ADOTKBnDi/6KTRkaUKP0zkmy7oxsKCzKVkEXiXcwB BZh+BuHg+Rpbu+GOCcE+f3x+xeOsrUFTltEOQj5kNVIzJc8OCh4gz/MDHp8IXk37ZHA== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794476380; h=Received:DKIM-Signature:From:To:Cc:In-Reply-To:References:Subject: Message-Id:Date:MIME-Version:Content-Type:Content-Transfer-Encoding: X-Mailer; bh=+qZVe7H4KMKBxamxaLHZL9oGHtOAsg+pNoHshyfPpG4=; b=gN1G7ccS7VIvP1xKJ9948DZYvE21h6B8bwL/yPESj99Xty5fNLPmBSzDuFVTMlkTMjzO saOqx07FzWs4W90ULeFq3RQ5tKKvxW244v5xDWRbhE3/AuwVa2H9Z+txUBphcTBzk+5Ti jPVScIf/rW+KR4EKJDogzxxDjZNyvIgwA9RMiTrGUqKGEL3JP9ZzQHN1inEF69jW7nvu1 DPG7eaT/nERjH2/O5u6yXIIFhpADQuJZ1BsAPogRSFqXq8VF3F/qnVpPruo/ozlPAPI/t XsZL1MyI49l/Jl5yo5b7UhTC+2MpbzZRVqC8fnwfrMgSk7JMyzoWnOmMogXFpivvmoA== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=ODECxA9y; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E3575606A336 for ; Thu, 12 Nov 2026 09:39:39 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=ODECxA9y Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5761B1F00A05; Thu, 12 Nov 2026 09:39:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1794476379; bh=+qZVe7H4KMKBxamxaLHZL9oGHtOAsg+pNoHshyfPpG4=; h=From:To:Cc:In-Reply-To:References:Subject:Date; b=ODECxA9y1Z6siZR8OwuwDYoboqLxQIe+qqo+J8zI+sp0yRBw8eyM3kziDFpXndHzD SzqJb37cgvobwr0NhpIFwN6EKQcHRMQMtWLqjPtFdI7TkHoKwVLstwdAltvciPMEFH uDcWdPxB0/l9k5ljUxPxSlpK9BJavvlwQsqsMQeCe9qv6QmxxVGqG2G7xHjOS0/I4m pm7Azv+TNXUWwscLesUbHMh/wGg7iGAy23eT4GBCeBVnA98fELahFI0yW9V/965Va7 XmsaZ18t1AuZZJB9uyJWo214iVZacmLDi9/tKYe5X6ZQpQOA/nI2KKKYY0kJHS5u+I fISEXgbfmoBCQ== From: David Hildenbrand To: David Hildenbrand , Zi Yan , Baolin Wang , "Liam R. Howlett" , Nico Pache , Ryan Roberts , Dev Jain , Barry Song , Lance Yang , Usama Arif , Kiryl Shutsemau , Andrew Morton , "Lorenzo Stoakes (ARM)" Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, "Jose A. Perez de Azpillaga" In-Reply-To: <20261110-khugepaged-latency-fix-v3-0-6eea743cf9a3@kernel.org> References: <20261110-khugepaged-latency-fix-v3-0-6eea743cf9a3@kernel.org> Subject: Re: [PATCH v3 0/3] mm/khugepaged: bound mmap_lock hold time when walking an mm's VMAs Message-Id: <179447637396.7058.8722598190835864744.b4-ty@b4> Date: Thu, 12 Nov 2026 10:39:33 +0100 X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-Mailer: b4 0.16.0 On Tue, 10 Nov 2026 17:19:10 +0000, Lorenzo Stoakes (ARM) wrote: > This series introduces a couple small changes to khugepaged to improve its > behaviour both in the face of mm->mmap_lock contention and to reduce that > lock contention when possible. > > Looking at the first change - if the mmap lock is contended, an attempted > mmap trylock in collapse_scan_mm_slot() will result in the scan being > aborted wherever it happens to be, and when next the mm is processed it > starts from the beginning again. > > [...] Applied, thanks! tree: mm/core.git branch: thp-7.5.misc Applied patches will appear soon in mm-next, followed by linux-next. Please report any outstanding bugs that were missed during review, so we can either drop the patch series or decide how to fix it up. It is encouraged to provide Acked-bys, Reviewed-bys, and Tested-bys even though the patches have already been applied. If possible, patch trailers will be updated. Note that commit hashes shown below are subject to change due to rebase, trailer updates or similar. Further, this is not a guarantee that the patches will go upstream. If in doubt, please check the listed branch. [1/3] Revert "mm/khugepaged: remove definition of struct khugepaged_mm_slot" https://git.kernel.org/mm/core/c/3734f01d [2/3] mm/khugepaged: scan mm's more efficiently under mmap_lock contention https://git.kernel.org/mm/core/c/f4720f7b [3/3] mm/khugepaged: release contended mmap read lock after scanning enough VMAs https://git.kernel.org/mm/core/c/f616e41a -- Cheers, David