From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jens Axboe Subject: Re: [PATCH 1/1] kernel/fs: fix I/O wait not accounted for RW O_DSYNC Date: Tue, 9 Feb 2016 09:27:34 -0700 Message-ID: <56BA1376.8080505@kernel.dk> References: <1455034058-84181-1-git-send-email-stephane.gasparini@intel.com> <1455034058-84181-2-git-send-email-stephane.gasparini@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from mail-ob0-f180.google.com ([209.85.214.180]:36217 "EHLO mail-ob0-f180.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932640AbcBIQ1h (ORCPT ); Tue, 9 Feb 2016 11:27:37 -0500 Received: by mail-ob0-f180.google.com with SMTP id ba1so189995267obb.3 for ; Tue, 09 Feb 2016 08:27:36 -0800 (PST) In-Reply-To: <1455034058-84181-2-git-send-email-stephane.gasparini@intel.com> Sender: linux-pm-owner@vger.kernel.org List-Id: linux-pm@vger.kernel.org To: Stephane Gasparini , linux-block@vger.kernel.org, linux-pm@vger.kernel.org, lenb@kernel.org, srinivas.pandruvada@linux.intel.com Cc: Stephane Gasparini , len.brown@linux.intel.com, philippe.longepe@linux.intel.com On 02/09/2016 09:07 AM, Stephane Gasparini wrote: > From: Stephane Gasparini > > When a process is doing Random Write with O_DSYNC flag > the I/O wait are not accounted in the kernel (get_cpu_iowait_time_us). > This is preventing the governor or the cpufreq driver to account for > I/O wait and thus use the right pstate Applied, thanks. -- Jens Axboe