From mboxrd@z Thu Jan 1 00:00:00 1970 From: Preeti U Murthy Subject: Re: [PATCH V3] cpuidle/governors: Fix logic in selection of idle states Date: Wed, 05 Feb 2014 09:30:51 +0530 Message-ID: <52F1B773.6050901@linux.vnet.ibm.com> References: <20140204083531.24802.63370.stgit@preeti.in.ibm.com> <52F0FE9F.501@linux.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <52F0FE9F.501@linux.intel.com> Sender: linux-kernel-owner@vger.kernel.org To: Arjan van de Ven Cc: linux-pm@vger.kernel.org, rjw@rjwysocki.net, linux-kernel@vger.kernel.org, len.brown@intel.com, benh@kernel.crashing.org, daniel.lezcano@linaro.org, srivatsa.bhat@linux.vnet.ibm.com, paulmck@linux.vnet.ibm.com, svaidy@linux.vnet.ibm.com List-Id: linux-pm@vger.kernel.org Hi Arjan, On 02/04/2014 08:22 PM, Arjan van de Ven wrote: > On 2/4/2014 12:35 AM, Preeti U Murthy wrote: >> The cpuidle governors today are not handling scenarios where no idle >> state >> can be chosen. Such scenarios coud arise if the user has disabled all the >> idle states at runtime or the latency requirement from the cpus is >> very strict. >> >> The menu governor returns 0th index of the idle state table when no other >> idle state is suitable. This is even when the idle state corresponding >> to this >> index is disabled or the latency requirement is strict and the >> exit_latency >> of the lowest idle state is also not acceptable. Hence this patch >> fixes this logic in the menu governor by defaulting to an idle state >> index >> of -1 unless any other state is suitable. > > state 0 is defined as polling, and polling ALWAYS should be ok Hmm.. you are right. This is convincing. There is no need for this patch. Thanks Regards Preeti U Murthy >