On 06/28/2012 01:24 PM, Srivatsa S. Bhat wrote:
> On 06/28/2012 02:16 PM, Daniel Lezcano wrote:
>> When the system is booted with some cpus offline, the idle
>> driver is not initialized. When a cpu is set online, the
>> acpi code call the intel idle init function. Unfortunately
>> this code introduce a dependency between intel_idle and acpi.
>>
>> This patch is intended to remove this dependency by using the
>> notifier of intel_idle. This patch has the benefit of
>> encapsulating the intel_idle driver and remove some exported
>> functions.
>>
>> Signed-off-by: Daniel Lezcano <daniel.lezcano@xxxxxxxxxx>
>
>
> Looks good to me.
Thanks for the review Srivatsa.
Shall I consider it as an acked-by ?
-- Daniel
>
> Regards,
> Srivatsa S. Bhat
>
>> ---
>> drivers/acpi/processor_driver.c | 7 ------
>> drivers/idle/intel_idle.c | 41 +++++++++++++++++++++++++-------------
>> include/linux/cpuidle.h | 7 ------
>> 3 files changed, 27 insertions(+), 28 deletions(-)
>>
>> diff --git a/drivers/acpi/processor_driver.c b/drivers/acpi/processor_driver.c
>> index 0734086..8648b29 100644
>> --- a/drivers/acpi/processor_driver.c
>> +++ b/drivers/acpi/processor_driver.c
>> @@ -427,18 +427,11 @@ static int acpi_cpu_soft_notify(struct notifier_block *nfb,
>> * Initialize missing things
>> */
>> if (pr->flags.need_hotplug_init) {
>> - struct cpuidle_driver *idle_driver =
>> - cpuidle_get_driver();
>> -
>> printk(KERN_INFO "Will online and init hotplugged "
>> "CPU: %d\n", pr->id);
>> WARN(acpi_processor_start(pr), "Failed to start CPU:"
>> " %d\n", pr->id);
>> pr->flags.need_hotplug_init = 0;
>> - if (idle_driver && !strcmp(idle_driver->name,
>> - "intel_idle")) {
>> - intel_idle_cpu_init(pr->id);
>> - }
>> /* Normal CPU soft online event */
>> } else {
>> acpi_processor_ppc_has_changed(pr, 0);
>> diff --git a/drivers/idle/intel_idle.c b/drivers/idle/intel_idle.c
>> index d0f59c3..fe95d54 100644
>> --- a/drivers/idle/intel_idle.c
>> +++ b/drivers/idle/intel_idle.c
>> @@ -96,6 +96,7 @@ static const struct idle_cpu *icpu;
>> static struct cpuidle_device __percpu *intel_idle_cpuidle_devices;
>> static int intel_idle(struct cpuidle_device *dev,
>> struct cpuidle_driver *drv, int index);
>> +static int intel_idle_cpu_init(int cpu);
>>
>> static struct cpuidle_state *cpuidle_state_table;
>>
>> @@ -302,22 +303,35 @@ static void __setup_broadcast_timer(void *arg)
>> clockevents_notify(reason, &cpu);
>> }
>>
>> -static int setup_broadcast_cpuhp_notify(struct notifier_block *n,
>> - unsigned long action, void *hcpu)
>> +static int cpu_hotplug_notify(struct notifier_block *n,
>> + unsigned long action, void *hcpu)
>> {
>> int hotcpu = (unsigned long)hcpu;
>> + struct cpuidle_device *dev;
>>
>> switch (action & 0xf) {
>> case CPU_ONLINE:
>> - smp_call_function_single(hotcpu, __setup_broadcast_timer,
>> - (void *)true, 1);
>> +
>> + if (lapic_timer_reliable_states != LAPIC_TIMER_ALWAYS_RELIABLE)
>> + smp_call_function_single(hotcpu, __setup_broadcast_timer,
>> + (void *)true, 1);
>> +
>> + /*
>> + * Some systems can hotplug a cpu at runtime after
>> + * the kernel has booted, we have to initialize the
>> + * driver in this case
>> + */
>> + dev = per_cpu_ptr(intel_idle_cpuidle_devices, hotcpu);
>> + if (!dev->registered)
>> + intel_idle_cpu_init(hotcpu);
>> +
>> break;
>> }
>> return NOTIFY_OK;
>> }
>>
>> -static struct notifier_block setup_broadcast_notifier = {
>> - .notifier_call = setup_broadcast_cpuhp_notify,
>> +static struct notifier_block cpu_hotplug_notifier = {
>> + .notifier_call = cpu_hotplug_notify,
>> };
>>
>> static void auto_demotion_disable(void *dummy)
>> @@ -405,10 +419,10 @@ static int intel_idle_probe(void)
>>
>> if (boot_cpu_has(X86_FEATURE_ARAT)) /* Always Reliable APIC Timer */
>> lapic_timer_reliable_states = LAPIC_TIMER_ALWAYS_RELIABLE;
>> - else {
>> + else
>> on_each_cpu(__setup_broadcast_timer, (void *)true, 1);
>> - register_cpu_notifier(&setup_broadcast_notifier);
>> - }
>> +
>> + register_cpu_notifier(&cpu_hotplug_notifier);
>>
>> pr_debug(PREFIX "v" INTEL_IDLE_VERSION
>> " model 0x%X\n", boot_cpu_data.x86_model);
>> @@ -494,7 +508,7 @@ static int intel_idle_cpuidle_driver_init(void)
>> * allocate, initialize, register cpuidle_devices
>> * @cpu: cpu/core to initialize
>> */
>> -int intel_idle_cpu_init(int cpu)
>> +static int intel_idle_cpu_init(int cpu)
>> {
>> int cstate;
>> struct cpuidle_device *dev;
>> @@ -539,7 +553,6 @@ int intel_idle_cpu_init(int cpu)
>>
>> return 0;
>> }
>> -EXPORT_SYMBOL_GPL(intel_idle_cpu_init);
>>
>> static int __init intel_idle_init(void)
>> {
>> @@ -581,10 +594,10 @@ static void __exit intel_idle_exit(void)
>> intel_idle_cpuidle_devices_uninit();
>> cpuidle_unregister_driver(&intel_idle_driver);
>>
>> - if (lapic_timer_reliable_states != LAPIC_TIMER_ALWAYS_RELIABLE) {
>> +
>> + if (lapic_timer_reliable_states != LAPIC_TIMER_ALWAYS_RELIABLE)
>> on_each_cpu(__setup_broadcast_timer, (void *)false, 1);
>> - unregister_cpu_notifier(&setup_broadcast_notifier);
>> - }
>> + unregister_cpu_notifier(&cpu_hotplug_notifier);
>>
>> return;
>> }
>> diff --git a/include/linux/cpuidle.h b/include/linux/cpuidle.h
>> index 5ab7183..66d7e0d 100644
>> --- a/include/linux/cpuidle.h
>> +++ b/include/linux/cpuidle.h
>> @@ -213,14 +213,7 @@ struct cpuidle_governor {
>> extern int cpuidle_register_governor(struct cpuidle_governor *gov);
>> extern void cpuidle_unregister_governor(struct cpuidle_governor *gov);
>>
>> -#ifdef CONFIG_INTEL_IDLE
>> -extern int intel_idle_cpu_init(int cpu);
>> #else
>> -static inline int intel_idle_cpu_init(int cpu) { return -1; }
>> -#endif
>> -
>> -#else
>> -static inline int intel_idle_cpu_init(int cpu) { return -1; }
>>
>> static inline int cpuidle_register_governor(struct cpuidle_governor *gov)
>> {return 0;}
>>
>
--
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