From mboxrd@z Thu Jan 1 00:00:00 1970 From: Srinivas Pandruvada Subject: [PATCH] cpufreq: use last policy after online Date: Tue, 1 Dec 2015 16:52:14 -0800 Message-ID: <1449017534-6127-1-git-send-email-srinivas.pandruvada@linux.intel.com> Return-path: Received: from mga02.intel.com ([134.134.136.20]:19607 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932196AbbLBAxY (ORCPT ); Tue, 1 Dec 2015 19:53:24 -0500 Sender: linux-pm-owner@vger.kernel.org List-Id: linux-pm@vger.kernel.org To: rafael.j.wysocki@intel.com, viresh.kumar@linaro.org Cc: linux-pm@vger.kernel.org, Srinivas Pandruvada For cpufreq drivers which use setpolicy interface, after offline->online the policy is set to default. This can be reproduced by setting the default policy of intel_pstate or longrun to ondemand and then change to "performance". After offline and online, the setpolicy will be called with the policy=ondemand. For drivers using governors this condition is handled by storing last_governor, during offline and restoring during online. The same should be done for drivers using setpolicy interface. Storing last_policy during offline and restoring during online. Signed-off-by: Srinivas Pandruvada --- drivers/cpufreq/cpufreq.c | 14 ++++++++++---- include/linux/cpufreq.h | 1 + 2 files changed, 11 insertions(+), 4 deletions(-) diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index a83c995..8412ce5 100644 --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -976,10 +976,14 @@ static int cpufreq_init_policy(struct cpufreq_policy *policy) new_policy.governor = gov; - /* Use the default policy if its valid. */ - if (cpufreq_driver->setpolicy) - cpufreq_parse_governor(gov->name, &new_policy.policy, NULL); - + /* Use the default policy if there is no last_policy. */ + if (cpufreq_driver->setpolicy) { + if (policy->last_policy) + new_policy.policy = policy->last_policy; + else + cpufreq_parse_governor(gov->name, &new_policy.policy, + NULL); + } /* set default policy */ return cpufreq_set_policy(policy, &new_policy); } @@ -1330,6 +1334,8 @@ static void cpufreq_offline_prepare(unsigned int cpu) if (has_target()) strncpy(policy->last_governor, policy->governor->name, CPUFREQ_NAME_LEN); + else + policy->last_policy = policy->policy; } else if (cpu == policy->cpu) { /* Nominate new CPU */ policy->cpu = cpumask_any(policy->cpus); diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h index ef4c5b1..177c768 100644 --- a/include/linux/cpufreq.h +++ b/include/linux/cpufreq.h @@ -77,6 +77,7 @@ struct cpufreq_policy { unsigned int suspend_freq; /* freq to set during suspend */ unsigned int policy; /* see above */ + unsigned int last_policy; /* policy before unplug */ struct cpufreq_governor *governor; /* see below */ void *governor_data; bool governor_enabled; /* governor start/stop flag */ -- 1.9.3