From: Viresh Kumar Date: Tue, 12 May 2015 06:52:12 +0000 (+0530) Subject: cpufreq: Don't traverse all active policies to find policy for a cpu X-Git-Tag: v4.14-rc1~5225^2~7^2~20 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=9104bb26c740cd4b2c9ee927f3caabbde0414558;p=platform%2Fkernel%2Flinux-rpi.git cpufreq: Don't traverse all active policies to find policy for a cpu We reach here while adding policy for a CPU and enter into the 'if' block only if a policy already exists for the CPU. As cpufreq_cpu_data is set for all policy->related_cpus now, when the policy is first added, we can use that to find the CPU's policy instead of traversing the list of all active policies. Acked-by: Saravana Kannan Signed-off-by: Viresh Kumar Signed-off-by: Rafael J. Wysocki --- diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index eb0c3a8..e6a63d6 100644 --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -1213,16 +1213,13 @@ static int cpufreq_add_dev(struct device *dev, struct subsys_interface *sif) return 0; /* Check if this CPU already has a policy to manage it */ - read_lock_irqsave(&cpufreq_driver_lock, flags); - for_each_active_policy(policy) { - if (cpumask_test_cpu(cpu, policy->related_cpus)) { - read_unlock_irqrestore(&cpufreq_driver_lock, flags); - ret = cpufreq_add_policy_cpu(policy, cpu, dev); - up_read(&cpufreq_rwsem); - return ret; - } + policy = per_cpu(cpufreq_cpu_data, cpu); + if (policy && !policy_is_inactive(policy)) { + WARN_ON(!cpumask_test_cpu(cpu, policy->related_cpus)); + ret = cpufreq_add_policy_cpu(policy, cpu, dev); + up_read(&cpufreq_rwsem); + return ret; } - read_unlock_irqrestore(&cpufreq_driver_lock, flags); /* * Restore the saved policy when doing light-weight init and fall back