From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f174.google.com (mail-pl1-f174.google.com [209.85.214.174]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id BBCE8191F86 for ; Thu, 29 Aug 2024 11:37:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.174 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724931473; cv=none; b=Tm4X77MBZyNi328P3C8oCxY+W0QL6wIIb76uUJELSbRxMikSOUuPFPqUpWmwmUOaT8I6Hp/gOyqLUs33Vec/YnDOIJUx/jMYd3u+bYKruIVBfsjeYy0FViutll7Ug47RiA8bpzLrlYz8JXXYfLljNohfztbQgzWbuSkui885hLk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724931473; c=relaxed/simple; bh=cNzbsA+TbK++Ak183JvAbBvIZCIt69jGcDVpJSPxpEk=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=adr4ygL/zLnX7PwK2iczxEdPYVEv67uEre7Dh/VY27M6zOuw1zC4sXV9uuEHKXZVBkUa98J73sDCnLa38uiwSKRFYJqfrte7hPZCRFuyDKKMNWmMpla1g8UqeLFwBpTJDYx8I0f1QlJMvx8H857dxPuVjrgm70r9wBvY0VUp1K4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=kernel.dk; spf=pass smtp.mailfrom=kernel.dk; dkim=pass (2048-bit key) header.d=kernel-dk.20230601.gappssmtp.com header.i=@kernel-dk.20230601.gappssmtp.com header.b=dCMAb7hQ; arc=none smtp.client-ip=209.85.214.174 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=kernel.dk Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=kernel.dk Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel-dk.20230601.gappssmtp.com header.i=@kernel-dk.20230601.gappssmtp.com header.b="dCMAb7hQ" Received: by mail-pl1-f174.google.com with SMTP id d9443c01a7336-2021537a8e6so3901185ad.2 for ; Thu, 29 Aug 2024 04:37:49 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20230601.gappssmtp.com; s=20230601; t=1724931469; x=1725536269; darn=vger.kernel.org; h=content-transfer-encoding:in-reply-to:from:content-language :references:cc:to:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date:message-id:reply-to; bh=3uwnGCH/YIzPLaHUb/2waUJ87bIA5++OGLa9jaJO7I8=; b=dCMAb7hQ5kGZLBBW5BJup3+L4zEz2hiCjVacfHWmJslYHpeGLp6nhbOsgHFm5Ak6u+ Mp03g30F8H/uHSXuXLvQmzt+lkrro6xkFE6VnFXg6/I2/5g2qjJ15r9o0PxDdAfJpZpB OyM0Lk02J22rA4+EMfALbLXmjLaNKNKZjSIzMm1B997Txf1SpqmAGj4w95NR8HcWhyM5 6q9Y0vV+pSA8kfVRXe07KNo1aDHHtPfowVkvCqUjEmWuXukMkgtRRKTmLvcGRoCWu17i NstFa8aniz3kpZHUDEjgXizqbYSBHARPFCyt2hn6u3WDXL+hFhsxXd8RbRVdyp/dxNop esqw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1724931469; x=1725536269; h=content-transfer-encoding:in-reply-to:from:content-language :references:cc:to:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=3uwnGCH/YIzPLaHUb/2waUJ87bIA5++OGLa9jaJO7I8=; b=nsyNobvm/jgkfsd40R0K3zulVS9pg/IZ2hZVkGgz5iJZ32rcze6m1YXUoUGxUPnOf9 izrekQpISpJ0KgakZIj6GxuBVxzrR7/mvplIinVNDLsNd0Nv8RB5sE0sS5LDTaP3sVSx DdliQuXjLS7HBCCsgPfo9cvRVmHuygNcZOegJvCFimECejn3Pe3mQ0tRazdZeRKUEWYC Cc4pg25Q2gpzFV2/ZkVDXJ+RxFG/wamO4nwkRkCnsuedwsOykEXFXKl0KwhL0jzgQwXv 0uvlcCJ1kjr7/xAR39m73znXN2361CZbZcTnezCB60MUu8kIqsInNgg4I5/MMgxY87XS TKXw== X-Gm-Message-State: AOJu0YzPJ/xwk/MmFw6/7zIqmCBu4p4z1TwJ9+oclb5R68PTxzJl1RXw I5ZbNuwTa81kA9oqRMdpaPqSbV9lxAovmFhwYRgg+2mX84XYfksqy8rl6DP7Hjsvx1Y1Cdg0wP7 k X-Google-Smtp-Source: AGHT+IFCzL8y6Y0fPNCJTLQKLePeR4IrAq+Gu1W+X4VnQGS0d3COJICgpMgUCJOuCGUPlJhD/q5ZmQ== X-Received: by 2002:a17:903:40c6:b0:202:35a8:42 with SMTP id d9443c01a7336-2050c46ca2bmr26184035ad.49.1724931468980; Thu, 29 Aug 2024 04:37:48 -0700 (PDT) Received: from [192.168.1.150] ([198.8.77.157]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-205152d6a82sm9666505ad.73.2024.08.29.04.37.48 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 29 Aug 2024 04:37:48 -0700 (PDT) Message-ID: Date: Thu, 29 Aug 2024 05:37:47 -0600 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: [RFC PATCH 1/2] bdev: add support for CPU latency PM QoS tuning To: Tero Kristo Cc: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org References: <20240829075423.1345042-1-tero.kristo@linux.intel.com> <20240829075423.1345042-2-tero.kristo@linux.intel.com> Content-Language: en-US From: Jens Axboe In-Reply-To: <20240829075423.1345042-2-tero.kristo@linux.intel.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 8/29/24 1:18 AM, Tero Kristo wrote: > diff --git a/block/bio.c b/block/bio.c > index e9e809a63c59..6c46d75345d7 100644 > --- a/block/bio.c > +++ b/block/bio.c > @@ -282,6 +282,8 @@ void bio_init(struct bio *bio, struct block_device *bdev, struct bio_vec *table, > bio->bi_max_vecs = max_vecs; > bio->bi_io_vec = table; > bio->bi_pool = NULL; > + > + bdev_update_cpu_latency_pm_qos(bio->bi_bdev); > } > EXPORT_SYMBOL(bio_init); This is entirely the wrong place to do this, presumably it should be done at IO dispatch time, not when something initializes a bio. And also feels like entirely the wrong way to go about this, adding overhead to potentially each IO dispatch, of which there can be millions per second. -- Jens Axboe