From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from 004.mia.mailroute.net (004.mia.mailroute.net [199.89.3.7]) (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 665001372; Wed, 18 Jun 2025 00:19:31 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=199.89.3.7 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750205973; cv=none; b=Hqm1ulDmdwyZMxIMvEeXQIwJup/szlP5LqIWyPMCowm12mQJJQzoUjHrRqXSbTWZGsrMEXEQ/xwRaL1ex+m/e3YezhOu0BFRI24ZX9Qe2ufaoLwivsUaqmyBAyfsG2HPtS153fIM1snlfVWH7L0iMKQfznD4irzv9c8iIEy7zcM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750205973; c=relaxed/simple; bh=icjYBfoK1conaL18TuKYZ97I3FET2WfZbndAKc8Ht6c=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=gr6ZUhopSLQRdaG4zwuJMd1lD7/AV7n3BXW0T5MSkkk1iTV0sHVqLvHT1rDYuMCzDHqjOuOsw7dIXpbJGs6/oKmgzp8ZC0pkJzZogEe3TBKNt7uXOuhOBC/ZAFV5tISPQfjgyAjoKuzSo5HNaB6cgQlZ9Qwoxkx0hopREGKpZKc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=acm.org; spf=pass smtp.mailfrom=acm.org; dkim=pass (2048-bit key) header.d=acm.org header.i=@acm.org header.b=1gi0s1uB; arc=none smtp.client-ip=199.89.3.7 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=acm.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=acm.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=acm.org header.i=@acm.org header.b="1gi0s1uB" Received: from localhost (localhost [127.0.0.1]) by 004.mia.mailroute.net (Postfix) with ESMTP id 4bMPW62TgMzm1HbY; Wed, 18 Jun 2025 00:19:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=acm.org; h= content-transfer-encoding:content-type:content-type:in-reply-to :from:from:content-language:references:subject:subject :user-agent:mime-version:date:date:message-id:received:received; s=mr01; t=1750205969; x=1752797970; bh=5BDRtoaYC7pOiogJOv1dRMkx 6/Lvg6YOlAmKmtoA/xQ=; b=1gi0s1uBys4zPl/mezcHdVI7rz4kYCrUmq5aGeJT wfRR0XxkLbqLUHmVe5D/uDB6HkbxIKSD4looZUDdeHs7Yh2gG9z82tJi6Z82O33I z4ZKRIIW6M4OweJIqeVHt+INbYRDTw2bWPCJBlqCDTk4IRho+QSSdQQQY3PKKOwG UZSlarZn+nyqNPOnioHfNTqSfcBiTvvXvRUaGJDKKbzPZQNXosVOnj6VX9R50j85 zg2YhpSn7BTsIAAzBQteISuyvl2gd9PtkaBVSb0EsejGBYrpYr4KJJC/QVCpH2te jcAK4fP4QkW374cy8J0XRVSVpY4q53BWlvLSIDsaIkZskw== X-Virus-Scanned: by MailRoute Received: from 004.mia.mailroute.net ([127.0.0.1]) by localhost (004.mia [127.0.0.1]) (mroute_mailscanner, port 10029) with LMTP id G4JOddGAgTwZ; Wed, 18 Jun 2025 00:19:29 +0000 (UTC) Received: from [192.168.51.14] (c-73-231-117-72.hsd1.ca.comcast.net [73.231.117.72]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: bvanassche@acm.org) by 004.mia.mailroute.net (Postfix) with ESMTPSA id 4bMPW21BPqzm1HbX; Wed, 18 Jun 2025 00:19:24 +0000 (UTC) Message-ID: <23f31e20-e58f-44e9-b81f-18811ce5c19c@acm.org> Date: Tue, 17 Jun 2025 17:19:22 -0700 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] block: mq-deadline: check if elevator is attached to queue in dd_finish_request To: Elijah Wright Cc: axboe@kernel.dk, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org References: <20250617205630.207696-1-git@elijahs.space> <1e25d17b-f481-485c-85a6-d5a8440c1c96@acm.org> Content-Language: en-US From: Bart Van Assche In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 6/17/25 3:52 PM, Elijah Wright wrote: > I see. would it be possible to detach the elevator from the queue in > elevator_exit instead? elevator_switch() is called with the request queue frozen. q_usage_counter is dropped after the blk_mq_finish_request() call returned. So what you described in your patch description can't happen. Bart.