x86/mce/therm_throt: Convert to hotplug state machine

Install the callbacks via the state machine and let the core invoke
the callbacks on the already online CPUs.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: rt@linuxtronix.de
Cc: Borislav Petkov <bp@alien8.de>
Cc: linux-edac@vger.kernel.org
Link: http://lkml.kernel.org/r/20161117183541.8588-2-bigeasy@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

diff --git a/arch/x86/kernel/cpu/mcheck/therm_throt.c b/arch/x86/kernel/cpu/mcheck/therm_throt.c
index 6b9dc4d18cccd1cd8fa6cf070b618bc878ad5a05..7f56620735ca938464d23e8d06685086ae00f909 100644 (file)
--- a/arch/x86/kernel/cpu/mcheck/therm_throt.c
+++ b/arch/x86/kernel/cpu/mcheck/therm_throt.c
@@ -271,58 +271,29 @@ static void thermal_throttle_remove_dev(struct device *dev)
 }
 
 /* Get notified when a cpu comes on/off. Be hotplug friendly. */
-static int
-thermal_throttle_cpu_callback(struct notifier_block *nfb,
-                             unsigned long action,
-                             void *hcpu)
+static int thermal_throttle_prepare(unsigned int cpu)
 {
-       unsigned int cpu = (unsigned long)hcpu;
-       struct device *dev;
-       int err = 0;
-
-       dev = get_cpu_device(cpu);
-
-       switch (action) {
-       case CPU_UP_PREPARE:
-       case CPU_UP_PREPARE_FROZEN:
-               err = thermal_throttle_add_dev(dev, cpu);
-               WARN_ON(err);
-               break;
-       case CPU_UP_CANCELED:
-       case CPU_UP_CANCELED_FROZEN:
-       case CPU_DEAD:
-       case CPU_DEAD_FROZEN:
-               thermal_throttle_remove_dev(dev);
-               break;
-       }
-       return notifier_from_errno(err);
+       struct device *dev = get_cpu_device(cpu);
+
+       return thermal_throttle_add_dev(dev, cpu);
 }
 
-static struct notifier_block thermal_throttle_cpu_notifier =
+static int thermal_throttle_dead(unsigned int cpu)
 {
-       .notifier_call = thermal_throttle_cpu_callback,
-};
+       struct device *dev = get_cpu_device(cpu);
+
+       thermal_throttle_remove_dev(dev);
+       return 0;
+}
 
 static __init int thermal_throttle_init_device(void)
 {
-       unsigned int cpu = 0;
-       int err;
-
        if (!atomic_read(&therm_throt_en))
                return 0;
 
-       cpu_notifier_register_begin();
-
-       /* connect live CPUs to sysfs */
-       for_each_online_cpu(cpu) {
-               err = thermal_throttle_add_dev(get_cpu_device(cpu), cpu);
-               WARN_ON(err);
-       }
-
-       __register_hotcpu_notifier(&thermal_throttle_cpu_notifier);
-       cpu_notifier_register_done();
-
-       return 0;
+       return cpuhp_setup_state(CPUHP_X86_THERM_PREPARE, "x86/therm:prepare",
+                                thermal_throttle_prepare,
+                                thermal_throttle_dead);
 }
 device_initcall(thermal_throttle_init_device);
 

diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h
index 79b96f647d643e1c715e90cd69d1160cd2f40452..aea6c6a63139bf5978cd469de21454d6086fe0f0 100644 (file)
--- a/include/linux/cpuhotplug.h
+++ b/include/linux/cpuhotplug.h
@@ -59,6 +59,7 @@ enum cpuhp_state {
        CPUHP_BLK_MQ_PREPARE,
        CPUHP_NET_FLOW_PREPARE,
        CPUHP_TOPOLOGY_PREPARE,
+       CPUHP_X86_THERM_PREPARE,
        CPUHP_TIMERS_DEAD,
        CPUHP_NOTF_ERR_INJ_PREPARE,
        CPUHP_MIPS_SOC_PREPARE,