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 D5AF6EEA8; Mon, 28 Jul 2025 03:55:35 +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=1753674936; cv=none; b=tCOeKo8zOlMZscxLuQyRv0/ce5NtX5yQgwBSbwX/M4SOknDIc9a3G1yNBPBy4uzpEbWpCIdN0SXi8Xz8j4yh+AWxLm0pJknFoxCL/bmrODxRzJBv+28losNsUlVI6VTyydm8ZW9gyeawb+5pmI5Ic2b5g7fBtM29TIpISKL2h7A= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1753674936; c=relaxed/simple; bh=IspbyPuUKbRFUFCRRceFUBq8nL8gFghMt5iHnrL2Oy8=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=MaQa2+cjOz7M1SILrtvxrH/VCVL9aHzzxywhltdmnkULscdyRoaGwsaDAGeZebHYlFqzizXoL+WOv42mEZ8NwfdqVFSDI/31lhRhqUteNFB99Zs+xILCtjje3r0Tz1Vcj3p76pBuEDPX4CcXTAli0iESvvl5nih+AR5H/HxjhHc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=DVZ9EdJ2; 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="DVZ9EdJ2" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4F1DCC4CEE7; Mon, 28 Jul 2025 03:55:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1753674935; bh=IspbyPuUKbRFUFCRRceFUBq8nL8gFghMt5iHnrL2Oy8=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=DVZ9EdJ2GF0i1b/2F9Fx7FZDHsZMRIt2Gap2FYjoeJ2E7nQkdZlPmv8KD9L3LuZcI 9fIWDq2T5jexzSaXc8Z90Ibj3+9bivbAOMsKs6Ew+FndLfKlY+UkfeDLsih+PRF3zv N6wWdTu0fLeyUpsPidckrgTGIgFiU+RQA8Sv4n+V/4RoB2AdYqLMgWuhDNhFlCQhBr 9nbxRA191u5LspyiTdA6lwqlLb8Sa0mNg9dH6U849LX28Vgf9DKWQUQKjeMLaWpBFg HHw8AWZfLFNzdRKCnIhgFIFQI++BttH7pb8pyWAUmRKrqZZvzYiHiIvn8mvnNfnFog l8QZQgnNVvziQ== Message-ID: <0f3f0978-eb42-4d83-81ad-e42cc482d674@kernel.org> Date: Mon, 28 Jul 2025 12:53:04 +0900 Precedence: bulk X-Mailing-List: linux-block@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2] blk-ioc: don't hold queue_lock for ioc_lookup_icq() To: Yu Kuai , jack@suse.cz, axboe@kernel.dk, linux-block@vger.kernel.org Cc: linux-kernel@vger.kernel.org, yukuai3@huawei.com, yi.zhang@huawei.com, yangerkun@huawei.com, johnny.chenyi@huawei.com References: <20250725180334.40187-1-yukuai@kernel.org> From: Damien Le Moal Content-Language: en-US Organization: Western Digital Research In-Reply-To: <20250725180334.40187-1-yukuai@kernel.org> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 7/26/25 3:03 AM, Yu Kuai wrote: > From: Yu Kuai > > Currently issue io can grab queue_lock three times from bfq_bio_merge(), > bfq_limit_depth() and bfq_prepare_request(), the queue_lock is not > necessary if icq is already created because both queue and ioc can't be > freed before io issuing is done, hence remove the unnecessary queue_lock > and use rcu to protect radix tree lookup. > > Noted this is also a prep patch to support request batch dispatching[1]. > > [1] https://lore.kernel.org/all/20250722072431.610354-1-yukuai1@huaweicloud.com/ > Signed-off-by: Yu Kuai Look OK. Reviewed-by: Damien Le Moal -- Damien Le Moal Western Digital Research