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 79E142C190; Tue, 11 Jun 2024 08:21:12 +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=1718094072; cv=none; b=mYYCJSWssC3tFGUuSMt6fBHQ832DLpztyNbb8Z5AfFG4AxeNgq3hd5AbG7TId9C/eMx8PIfSW6IkoyJMZVh9SvHkHZuN3rfcX6OmE8/+a0rOcO4WLP2TZGYihozHw5THWzh0mpvy2Z0Dr7/hIzHBpVsXwjs+B4XGaRjRPVsdzs8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718094072; c=relaxed/simple; bh=JnxwCboQk8q7RlLZlW4EySiyxLKgUjk778Traf3fmoA=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=lBDUqsAgwSmFfyV2pmb21pY387e9dqrgvOJCujLgKtc33B17/PuCVpS8GP3zeJ2g55FPisMWz/RNxPGtLfZ/3dEGtZGtaSfSCaHFVM7+cC8IIDQErIBMBzonDeFzu7tpgp/wkuLcg50CxM7rMcEWJs72x8Va1hMbbGeUfpkXD50= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=T4lYpc9o; 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="T4lYpc9o" Received: by smtp.kernel.org (Postfix) with ESMTPSA id EC86FC2BD10; Tue, 11 Jun 2024 08:21:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1718094072; bh=JnxwCboQk8q7RlLZlW4EySiyxLKgUjk778Traf3fmoA=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=T4lYpc9oPKzbZgXNScRXj6fCCJuF2imMpVDO2TmKoprDVoEMAifMh8yJGso4Vfp5y OgmplPRZ+vOoc/3W5Z2/vvUR59B9dvvmiJ3TXlfZjt80a4a+B616vcQsbnQtB8TQlx hCCsxl7ULUCU4AFz7+jEuDHX9a+L+WI83HnZLceoWGeScqnvdznMEcmPFZA+cvHULW tsWbQ1wsp08S3pZw6QSDKAzAlfLw76qcbODE/Rb62WAcCaMIMds4nLrdbgO640++hO MSBTvFYh9It5CVDUDafarknsby40aO62VVd0BASXyBUwrOv7fDEDdarOIcY3IX1DTf +T3qkIPPHiYZg== Message-ID: Date: Tue, 11 Jun 2024 17:21:07 +0900 Precedence: bulk X-Mailing-List: linux-bcache@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 21/26] block: move the poll flag to queue_limits To: Christoph Hellwig , Jens Axboe Cc: Geert Uytterhoeven , Richard Weinberger , Philipp Reisner , Lars Ellenberg , =?UTF-8?Q?Christoph_B=C3=B6hmwalder?= , Josef Bacik , Ming Lei , "Michael S. Tsirkin" , Jason Wang , =?UTF-8?Q?Roger_Pau_Monn=C3=A9?= , Alasdair Kergon , Mike Snitzer , Mikulas Patocka , Song Liu , Yu Kuai , Vineeth Vijayan , "Martin K. Petersen" , linux-m68k@lists.linux-m68k.org, linux-um@lists.infradead.org, drbd-dev@lists.linbit.com, nbd@other.debian.org, linuxppc-dev@lists.ozlabs.org, ceph-devel@vger.kernel.org, virtualization@lists.linux.dev, xen-devel@lists.xenproject.org, linux-bcache@vger.kernel.org, dm-devel@lists.linux.dev, linux-raid@vger.kernel.org, linux-mmc@vger.kernel.org, linux-mtd@lists.infradead.org, nvdimm@lists.linux.dev, linux-nvme@lists.infradead.org, linux-s390@vger.kernel.org, linux-scsi@vger.kernel.org, linux-block@vger.kernel.org References: <20240611051929.513387-1-hch@lst.de> <20240611051929.513387-22-hch@lst.de> Content-Language: en-US From: Damien Le Moal Organization: Western Digital Research In-Reply-To: <20240611051929.513387-22-hch@lst.de> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 6/11/24 2:19 PM, Christoph Hellwig wrote: > Move the poll flag into the queue_limits feature field so that it > can be set atomically and all I/O is frozen when changing the flag. > > Stacking drivers are simplified in that they now can simply set the > flag, and blk_stack_limits will clear it when the features is not > supported by any of the underlying devices. > > Signed-off-by: Christoph Hellwig Kind of the same remark as for io_stat about this not really being a device feature. But I guess seeing "features" as a queue feature rather than just a device feature makes it OK to have poll (and io_stat) as a feature rather than a flag. So: Reviewed-by: Damien Le Moal -- Damien Le Moal Western Digital Research