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 B820C276024 for ; Mon, 23 Jun 2025 15:43:08 +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=1750693388; cv=none; b=PrJgy2kdtzNfjOD5EH0AjCWFyGQ+QX6CthsV6OY4y+97dkCFT+HWxcfChVwU8BDFRwQ6Wb65ZRl2f4TsozaveMn0fZsNkcuirfymrYwtlcnt1HN5SAXa4vEJmLZ9xriOMN3WwbgU/ADyYzXyH7SkMyVM/NIqLmGgG70Kzf4g8wQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750693388; c=relaxed/simple; bh=0eaGEA1wt6jq4T6sIubQFT2smAr+omb1CgShoBvET0w=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=NEvnhnu+2LT3KZTE7i/z5koh68rQreSDBOuxTvZBxg2OJSFP17F+rnVYKZG/Ob0Z6MltWB/K6JdjD85lYslT2iLjbVBFPSnQVqlp3BXwX3wuj/lMP/q+tIb89A/r3ONZ3sunmyfQCchBc51jxf4Z6QZnvZtFiGeNaEE7Ptd1px4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=cfbMtAAn; 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="cfbMtAAn" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B700AC4CEEA; Mon, 23 Jun 2025 15:43:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1750693388; bh=0eaGEA1wt6jq4T6sIubQFT2smAr+omb1CgShoBvET0w=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=cfbMtAAn4mryyrMA98mi6BHTTiOmVBjiy5mXbLojnyny316jTf4WItkT0Sdzd804g F9f3kKvBsw3zipxgJMBB8RNGrbLulaXQMAsC0TBezd/Ep+pxF57KQMOcTQpY/51Jai Dg8NicADXWuL0pZY+kTyqoLOVH5rbzYcBxj0p2gr9kMb48Q5ZfKSj1E4Aje7PszuML l1GX/tHjPSoi6FavmikH1ewuwtzK5PByjDdXLcVdZrA9FcCjEyK/G5LLtxmrGQQPTX tJZyO6ZIGBlfJ5eutJRQSr/vf915nb3K92zf3dowEYG4kwzNa2jXaQS/USqX57qLsW 0WoI6ARIyfADQ== Date: Mon, 23 Jun 2025 09:43:05 -0600 From: Keith Busch To: Christoph Hellwig Cc: Jens Axboe , Sagi Grimberg , Chaitanya Kulkarni , Kanchan Joshi , Leon Romanovsky , Nitesh Shetty , Logan Gunthorpe , linux-block@vger.kernel.org, linux-nvme@lists.infradead.org, Leon Romanovsky Subject: Re: [PATCH 1/8] block: don't merge different kinds of P2P transfers in a single bio Message-ID: References: <20250623141259.76767-1-hch@lst.de> <20250623141259.76767-2-hch@lst.de> Precedence: bulk X-Mailing-List: linux-block@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250623141259.76767-2-hch@lst.de> On Mon, Jun 23, 2025 at 04:12:23PM +0200, Christoph Hellwig wrote: > To get out of the DMA mapping helpers having to check every segment for > it's P2P status, ensure that bios either contain P2P transfers or non-P2P > transfers, and that a P2P bio only contains ranges from a single device. > > This means we do the page zone access in the bio add path where it should > be still page hot, and will only have do the fairly expensive P2P topology > lookup once per bio down in the DMA mapping path, and only for already > marked bios. Looks good. Reviewed-by: Keith Busch