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. In order to make it work, the notifier
must be initialized in the right order, acpi then intel_idle.
This is done in the Makefile. This patch has the benefit of
encapsulating the intel_idle driver and remove some exported
functions.
Signed-off-by: Daniel Lezcano <daniel.lezcano@xxxxxxxxxx>
---
drivers/Makefile | 3 ++-
drivers/acpi/processor_driver.c | 7 -------
drivers/idle/intel_idle.c | 22 ++++++++++++++--------
include/linux/cpuidle.h | 7 -------
4 files changed, 16 insertions(+), 23 deletions(-)
diff --git a/drivers/Makefile b/drivers/Makefile
index 2ba29ff..a2454b8 100644
--- a/drivers/Makefile
+++ b/drivers/Makefile
@@ -12,8 +12,9 @@ obj-$(CONFIG_PCI) += pci/
obj-$(CONFIG_PARISC) += parisc/
obj-$(CONFIG_RAPIDIO) += rapidio/
obj-y += video/
-obj-y += idle/
+# acpi must come before idle for initialization
obj-$(CONFIG_ACPI) += acpi/
+obj-y += idle/
obj-$(CONFIG_SFI) += sfi/
# PnP must come after ACPI since it will eventually need to check if acpi
# was used and do nothing if so
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..4c36039 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 +303,28 @@ 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);
+
+ 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)
@@ -407,7 +414,7 @@ static int intel_idle_probe(void)
lapic_timer_reliable_states = LAPIC_TIMER_ALWAYS_RELIABLE;
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
@@ -494,7 +501,7 @@ 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 +546,6 @@ int intel_idle_cpu_init(int cpu)
return 0;
}
-EXPORT_SYMBOL_GPL(intel_idle_cpu_init);
static int __init intel_idle_init(void)
{
@@ -583,7 +589,7 @@ static void __exit intel_idle_exit(void)
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;}
--
1.7.5.4
