Merge branch 'for-linus' of git://git390.marist.edu/pub/scm/linux-2.6
[safe/jmp/linux-2.6] / arch / x86 / kernel / cpu / mcheck / therm_throt.c
index 15f2bc0..e1a0a3b 100644 (file)
 /* How long to wait between reporting thermal events */
 #define CHECK_INTERVAL         (300 * HZ)
 
-static DEFINE_PER_CPU(__u64, next_check) = INITIAL_JIFFIES;
-static DEFINE_PER_CPU(unsigned long, thermal_throttle_count);
+/*
+ * Current thermal throttling state:
+ */
+struct thermal_state {
+       bool                    is_throttled;
+
+       u64                     next_check;
+       unsigned long           throttle_count;
+       unsigned long           last_throttle_count;
+};
 
-static atomic_t therm_throt_en         = ATOMIC_INIT(0);
+static DEFINE_PER_CPU(struct thermal_state, thermal_state);
+
+static atomic_t therm_throt_en = ATOMIC_INIT(0);
+
+static u32 lvtthmr_init __read_mostly;
 
 #ifdef CONFIG_SYSFS
 #define define_therm_throt_sysdev_one_ro(_name)                                \
        static SYSDEV_ATTR(_name, 0444, therm_throt_sysdev_show_##_name, NULL)
 
 #define define_therm_throt_sysdev_show_func(name)                      \
-static ssize_t therm_throt_sysdev_show_##name(struct sys_device *dev,  \
-                                       struct sysdev_attribute *attr,  \
-                                             char *buf)                \
+                                                                       \
+static ssize_t therm_throt_sysdev_show_##name(                         \
+                       struct sys_device *dev,                         \
+                       struct sysdev_attribute *attr,                  \
+                       char *buf)                                      \
 {                                                                      \
        unsigned int cpu = dev->id;                                     \
        ssize_t ret;                                                    \
@@ -54,7 +68,7 @@ static ssize_t therm_throt_sysdev_show_##name(struct sys_device *dev, \
        preempt_disable();      /* CPU hotplug */                       \
        if (cpu_online(cpu))                                            \
                ret = sprintf(buf, "%lu\n",                             \
-                             per_cpu(thermal_throttle_##name, cpu));   \
+                             per_cpu(thermal_state, cpu).name);        \
        else                                                            \
                ret = 0;                                                \
        preempt_enable();                                               \
@@ -62,11 +76,11 @@ static ssize_t therm_throt_sysdev_show_##name(struct sys_device *dev,       \
        return ret;                                                     \
 }
 
-define_therm_throt_sysdev_show_func(count);
-define_therm_throt_sysdev_one_ro(count);
+define_therm_throt_sysdev_show_func(throttle_count);
+define_therm_throt_sysdev_one_ro(throttle_count);
 
 static struct attribute *thermal_throttle_attrs[] = {
-       &attr_count.attr,
+       &attr_throttle_count.attr,
        NULL
 };
 
@@ -92,31 +106,43 @@ static struct attribute_group thermal_throttle_attr_group = {
  *          1 : Event should be logged further, and a message has been
  *              printed to the syslog.
  */
-static int therm_throt_process(int curr)
+static int therm_throt_process(bool is_throttled)
 {
-       unsigned int cpu = smp_processor_id();
-       __u64 tmp_jiffs = get_jiffies_64();
+       struct thermal_state *state;
+       unsigned int this_cpu;
+       bool was_throttled;
+       u64 now;
 
-       if (curr)
-               __get_cpu_var(thermal_throttle_count)++;
+       this_cpu = smp_processor_id();
+       now = get_jiffies_64();
+       state = &per_cpu(thermal_state, this_cpu);
 
-       if (time_before64(tmp_jiffs, __get_cpu_var(next_check)))
+       was_throttled = state->is_throttled;
+       state->is_throttled = is_throttled;
+
+       if (is_throttled)
+               state->throttle_count++;
+
+       if (time_before64(now, state->next_check) &&
+                       state->throttle_count != state->last_throttle_count)
                return 0;
 
-       __get_cpu_var(next_check) = tmp_jiffs + CHECK_INTERVAL;
+       state->next_check = now + CHECK_INTERVAL;
+       state->last_throttle_count = state->throttle_count;
 
        /* if we just entered the thermal event */
-       if (curr) {
-               printk(KERN_CRIT "CPU%d: Temperature above threshold, "
-                      "cpu clock throttled (total events = %lu)\n", cpu,
-                      __get_cpu_var(thermal_throttle_count));
+       if (is_throttled) {
+               printk(KERN_CRIT "CPU%d: Temperature above threshold, cpu clock throttled (total events = %lu)\n", this_cpu, state->throttle_count);
 
                add_taint(TAINT_MACHINE_CHECK);
-       } else {
-               printk(KERN_CRIT "CPU%d: Temperature/speed normal\n", cpu);
+               return 1;
+       }
+       if (was_throttled) {
+               printk(KERN_INFO "CPU%d: Temperature/speed normal\n", this_cpu);
+               return 1;
        }
 
-       return 1;
+       return 0;
 }
 
 #ifdef CONFIG_SYSFS
@@ -164,7 +190,7 @@ thermal_throttle_cpu_callback(struct notifier_block *nfb,
                mutex_unlock(&therm_cpu_lock);
                break;
        }
-       return err ? NOTIFY_BAD : NOTIFY_OK;
+       return notifier_from_errno(err);
 }
 
 static struct notifier_block thermal_throttle_cpu_notifier __cpuinitdata =
@@ -206,7 +232,7 @@ static void intel_thermal_interrupt(void)
        __u64 msr_val;
 
        rdmsrl(MSR_IA32_THERM_STATUS, msr_val);
-       if (therm_throt_process(msr_val & THERM_STATUS_PROCHOT))
+       if (therm_throt_process((msr_val & THERM_STATUS_PROCHOT) != 0))
                mce_log_therm_throt_event(msr_val);
 }
 
@@ -230,14 +256,34 @@ asmlinkage void smp_thermal_interrupt(struct pt_regs *regs)
        ack_APIC_irq();
 }
 
+/* Thermal monitoring depends on APIC, ACPI and clock modulation */
+static int intel_thermal_supported(struct cpuinfo_x86 *c)
+{
+       if (!cpu_has_apic)
+               return 0;
+       if (!cpu_has(c, X86_FEATURE_ACPI) || !cpu_has(c, X86_FEATURE_ACC))
+               return 0;
+       return 1;
+}
+
+void __init mcheck_intel_therm_init(void)
+{
+       /*
+        * This function is only called on boot CPU. Save the init thermal
+        * LVT value on BSP and use that value to restore APs' thermal LVT
+        * entry BIOS programmed later
+        */
+       if (intel_thermal_supported(&boot_cpu_data))
+               lvtthmr_init = apic_read(APIC_LVTTHMR);
+}
+
 void intel_init_thermal(struct cpuinfo_x86 *c)
 {
        unsigned int cpu = smp_processor_id();
        int tm2 = 0;
        u32 l, h;
 
-       /* Thermal monitoring depends on ACPI and clock modulation*/
-       if (!cpu_has(c, X86_FEATURE_ACPI) || !cpu_has(c, X86_FEATURE_ACC))
+       if (!intel_thermal_supported(c))
                return;
 
        /*
@@ -246,7 +292,20 @@ void intel_init_thermal(struct cpuinfo_x86 *c)
         * since it might be delivered via SMI already:
         */
        rdmsr(MSR_IA32_MISC_ENABLE, l, h);
-       h = apic_read(APIC_LVTTHMR);
+
+       /*
+        * The initial value of thermal LVT entries on all APs always reads
+        * 0x10000 because APs are woken up by BSP issuing INIT-SIPI-SIPI
+        * sequence to them and LVT registers are reset to 0s except for
+        * the mask bits which are set to 1s when APs receive INIT IPI.
+        * Always restore the value that BIOS has programmed on AP based on
+        * BSP's info we saved since BIOS is always setting the same value
+        * for all threads/cores
+        */
+       apic_write(APIC_LVTTHMR, lvtthmr_init);
+
+       h = lvtthmr_init;
+
        if ((l & MSR_IA32_MISC_ENABLE_TM1) && (h & APIC_DM_SMI)) {
                printk(KERN_DEBUG
                       "CPU%d: Thermal monitoring handled by SMI\n", cpu);
@@ -288,8 +347,8 @@ void intel_init_thermal(struct cpuinfo_x86 *c)
        l = apic_read(APIC_LVTTHMR);
        apic_write(APIC_LVTTHMR, l & ~APIC_LVT_MASKED);
 
-       printk(KERN_INFO "CPU%d: Thermal monitoring enabled (%s)\n",
-              cpu, tm2 ? "TM2" : "TM1");
+       printk_once(KERN_INFO "CPU0: Thermal monitoring enabled (%s)\n",
+                      tm2 ? "TM2" : "TM1");
 
        /* enable thermal throttle processing */
        atomic_set(&therm_throt_en, 1);