Re: [PATCH v10 2/2] cpufreq: powernv: Add sysfs attributes to show throttle stats
From: Viresh Kumar <viresh.kumar@linaro.org>
Date: 2016-02-29 06:39:27
Also in:
linux-api, linux-pm, lkml
On 26-02-16, 16:06, Shilpasri G Bhat wrote:
quoted hunk ↗ jump to hunk
+static int powernv_cpufreq_policy_notifier(struct notifier_block *nb, + unsigned long action, void *data) +{ + struct cpufreq_policy *policy = data; + int ret; + + if (action == CPUFREQ_CREATE_POLICY) { + ret = sysfs_create_group(&policy->kobj, &throttle_attr_grp); + if (ret) + pr_info("Failed to create throttle stats directory for cpu %d\n", + policy->cpu); + } else if (action == CPUFREQ_REMOVE_POLICY) { + sysfs_remove_group(&policy->kobj, &throttle_attr_grp); + } + + return NOTIFY_DONE; +} + +static struct notifier_block powernv_cpufreq_policy_nb = { + .notifier_call = powernv_cpufreq_policy_notifier, + .next = NULL, +}; + static void powernv_cpufreq_stop_cpu(struct cpufreq_policy *policy) { struct powernv_smp_call_data freq_data;@@ -603,6 +708,8 @@ static inline void clean_chip_info(void) static inline void unregister_all_notifiers(void) { + cpufreq_unregister_notifier(&powernv_cpufreq_policy_nb, + CPUFREQ_POLICY_NOTIFIER); opal_message_notifier_unregister(OPAL_MSG_OCC, &powernv_cpufreq_opal_nb); unregister_reboot_notifier(&powernv_cpufreq_reboot_nb);@@ -628,6 +735,8 @@ static int __init powernv_cpufreq_init(void) register_reboot_notifier(&powernv_cpufreq_reboot_nb); opal_message_notifier_register(OPAL_MSG_OCC, &powernv_cpufreq_opal_nb); + cpufreq_register_notifier(&powernv_cpufreq_policy_nb, + CPUFREQ_POLICY_NOTIFIER); rc = cpufreq_register_driver(&powernv_cpufreq_driver); if (!rc)
@Rafael: This driver needs to do this *ugly* notifier hack, just because we aren't doing kobject_add() for policy->kobj before ->init(). And we did that because, we wanted to create the policyX structure with the first CPU in policy->related_cpus mask and related_cpus mask isn't available until we call ->init().. Should we do something in core to make this easier for this driver? -- viresh