From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from verein.lst.de (verein.lst.de [213.95.11.211]) (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 D3954146A66 for ; Thu, 21 Aug 2025 08:35:50 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=213.95.11.211 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755765353; cv=none; b=hm3fJjnu4u/+DOXtTBXSLKSRSJYC9pMonBgU+/tSjZf7eTQ5XUZC/TBbDz/NU17Slh3nxA6a6K6//MvGJrV7wTfKsU8S0Us/TsYcOqVrbrHCvdUFOal0xO52iZeBBngV8XY67QWn1iGcrPHDqrzIWPLCQc+CJdS1O8zVmRo19Hw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755765353; c=relaxed/simple; bh=lysEUEk7RrDtr0FUv+P4PfID5/YBMrJFBdUZXQ7wN2s=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=o6EHGOtGRe7vGjngdeyKDDogQZZgd0J1m4KfkU/CePFTGBt+HOekowh5qQcgQK5P2g3IxuhvP7VcnCKgz7vw6ZSFmpMFWFOM9m3T3culHi2/6tZGwDfAqjhamYKmCFVm63r/xM3tC37BnyEhyRUBABSN181G5BVO+j/CeNNrUWg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=lst.de; spf=pass smtp.mailfrom=lst.de; arc=none smtp.client-ip=213.95.11.211 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=lst.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=lst.de Received: by verein.lst.de (Postfix, from userid 2407) id 17E06227A88; Thu, 21 Aug 2025 10:35:38 +0200 (CEST) Date: Thu, 21 Aug 2025 10:35:37 +0200 From: Christoph Hellwig To: John Garry Cc: kbusch@kernel.org, axboe@kernel.dk, hch@lst.de, sagi@grimberg.me, linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org, tytso@mit.edu, nilay@linux.ibm.com, martin.petersen@oracle.com, djwong@kernel.org, mcgrof@infradead.org Subject: Re: [RFC PATCH] nvme: add an opt-in to use AWUPF Message-ID: <20250821083537.GB29224@lst.de> References: <20250820150220.1923826-1-john.g.garry@oracle.com> Precedence: bulk X-Mailing-List: linux-kernel@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: <20250820150220.1923826-1-john.g.garry@oracle.com> User-Agent: Mutt/1.5.17 (2007-11-01) On Wed, Aug 20, 2025 at 03:02:20PM +0000, John Garry wrote: > As described at [0], many parts of the atomic write specification are > lacking. I like your british understatement. > + list_for_each_entry(tmp, &subsys->ctrls, subsys_entry) > + nvme_queue_scan(tmp); queueing a full rescan here seems expensive. What about just keeping the awupf value in our internal data structures and always use it for the physical block size calculation, but only apply it to the atomic limits based on a flag?