From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9782435979; Thu, 13 Nov 2025 12:34:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763037269; cv=none; b=ND73IWODeRgk/0JnrsLoTalqAwXjAZZW12uMREkITrKiqglrZn+qZCVTMMIEi1fWhVFrcPfb5Gmzynruq1u+wpcaa7HjDR7H8WqEejJLGAMTm20qJFe+IYn1eMRJgNcgQ5CFjEc+520YquoEAdetjT2m29pEmPvLxBuan1mxQII= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763037269; c=relaxed/simple; bh=y1FfFIuMb0svp4ymlKmSDs7EFvaJvR5A3gJ3lpcq8Uk=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=qZ7k2dnf6qFEtUZrvWCDqqivuKl4+p+2tTs8xewhXErHgK/qsFoksVQBp+eDiJfeu6ouBcb/8rwNRQ/BdEApqF3Ps/x/yHnaP6v+WurXjyzKlBUs8JqVEv/38D9guXzZ8KCEMnNy/PwqL/RbOPEJs3GLN5emUO6KdKUT80ujDeY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=EOp/uNGL; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="EOp/uNGL" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 95A64C4CEF8; Thu, 13 Nov 2025 12:34:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1763037269; bh=y1FfFIuMb0svp4ymlKmSDs7EFvaJvR5A3gJ3lpcq8Uk=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=EOp/uNGLEJX2/o1A0Oqqre+Il30QU6+REZ6YFDPWH0Meu5sP92HduOMkUe8kYKDAB VdMLglbLi+06rRrPRmZtPa85qJJEDgpngLeHOzUgN1sNS8CURZ8cVUCHj7//ChyqxF VuOuLY62yswpDC7bqM25vTrSPw6RUWv/LeQgStQLbLM2OrQuNcrt/3iInfvUmER6AV Nc+T6QelxZUkCLsxA1HPvQevv9ZkT7AKrzBRgRHmpmiBzB/hsqvjQmmfHqp2ZR80oO H3l+CR6hjebnQdqloBIy7TOa2FcbeyT4jGxT7OutE15lQOo+L85dtISsLNkHoQJUIp agdcL9uWkwFxQ== Message-ID: <13db54a4-5f02-4b57-8ff9-6298c2c4b8d3@kernel.org> Date: Thu, 13 Nov 2025 13:34:22 +0100 Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [RFC PATCH 2/8] mm: Add PG_atomic To: Matthew Wilcox , Ojaswin Mujoo Cc: Christian Brauner , djwong@kernel.org, ritesh.list@gmail.com, john.g.garry@oracle.com, tytso@mit.edu, dchinner@redhat.com, hch@lst.de, linux-xfs@vger.kernel.org, linux-kernel@vger.kernel.org, linux-ext4@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, jack@suse.cz, nilay@linux.ibm.com, martin.petersen@oracle.com, rostedt@goodmis.org, axboe@kernel.dk, linux-block@vger.kernel.org, linux-trace-kernel@vger.kernel.org References: <5f0a7c62a3c787f2011ada10abe3826a94f99e17.1762945505.git.ojaswin@linux.ibm.com> From: "David Hildenbrand (Red Hat)" Content-Language: en-US In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 12.11.25 16:56, Matthew Wilcox wrote: > On Wed, Nov 12, 2025 at 04:36:05PM +0530, Ojaswin Mujoo wrote: >> From: John Garry >> >> Add page flag PG_atomic, meaning that a folio needs to be written back >> atomically. This will be used by for handling RWF_ATOMIC buffered IO >> in upcoming patches. > > Page flags are a precious resource. I'm not thrilled about allocating one > to this rather niche usecase. Fully agreed. -- Cheers David