From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753063AbaI0Tlz (ORCPT ); Sat, 27 Sep 2014 15:41:55 -0400 Received: from v094114.home.net.pl ([79.96.170.134]:55987 "HELO v094114.home.net.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1751828AbaI0Tlx (ORCPT ); Sat, 27 Sep 2014 15:41:53 -0400 From: "Rafael J. Wysocki" To: Wang Weidong Cc: viresh.kumar@linaro.org, linux-pm@vger.kernel.org, "linux-kernel@vger.kernel.org >> \"linux-kernel@vger.kernel.org\"" Subject: Re: [RESEND PATCH] acpi-cpufreq: get the cur_freq from acpi_processor_performance states Date: Sat, 27 Sep 2014 22:01:46 +0200 Message-ID: <2361937.mQR3H5xj3F@vostro.rjw.lan> User-Agent: KMail/4.11.5 (Linux/3.16.0-rc5+; KDE/4.11.5; x86_64; ; ) In-Reply-To: <54264C0B.1000607@huawei.com> References: <53F589C3.4050504@huawei.com> <2075276.PKjjuvNeys@vostro.rjw.lan> <54264C0B.1000607@huawei.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="utf-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Saturday, September 27, 2014 01:32:59 PM Wang Weidong wrote: > On 2014/9/27 7:21, Rafael J. Wysocki wrote: > > On Thursday, August 21, 2014 01:55:15 PM Wang Weidong wrote: > >> As the initialized freq_tables maybe different from the p-states > >> values, so the array index is different as well. > >> > >> p-states value: [2400 2400 2000 ...], while the freq_tables: > >> [2400 2000 ... CPUFREQ_TABLE_END]. After setted the freqs 2000, > >> the perf->state is 3 while the freqs_table's index should be 2. > >> So when call the get_cur_freq_on_cpu, the freqs value we get > >> is 2400. > >> > >> So, fix the problem with the correct tables. > > > > What you're saying is basically that freq_table and perf->states > > diverge at one point. Shouldn't we re-generate freq_table in that > > case instead of fixing up get_cur_freq_on_cpu() only in a quite > > indirect way? > > > Hi Rafael, > > Thanks for your reply. > > You mean that we should re-generate the freq_table in that case? > Could we fix the table init like this: > > --- a/drivers/cpufreq/acpi-cpufreq.c > +++ b/drivers/cpufreq/acpi-cpufreq.c > @@ -779,7 +779,7 @@ static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy) > > /* table init */ > for (i = 0; i < perf->state_count; i++) { > - if (i > 0 && perf->states[i].core_frequency >= > + if (i > 0 && perf->states[i].core_frequency > > data->freq_table[valid_states-1].frequency / 1000) > continue; > > when the value is same, we just keep the value into the freq_table. That would only be OK if it is guaranteed that the set of available states hasn't changed, which I'm not sure is the case. Rafael