panic(msg);
}
-static int mce_available(struct cpuinfo_x86 *c)
+int mce_available(struct cpuinfo_x86 *c)
{
if (mce_dont_init)
return 0;
static void mce_disable_cpu(void *h)
{
int i;
+ unsigned long action = *(unsigned long *)h;
if (!mce_available(¤t_cpu_data))
return;
+ if (!(action & CPU_TASKS_FROZEN))
+ cmci_clear();
for (i = 0; i < banks; i++)
wrmsrl(MSR_IA32_MC0_CTL + i*4, 0);
}
static void mce_reenable_cpu(void *h)
{
int i;
+ unsigned long action = *(unsigned long *)h;
if (!mce_available(¤t_cpu_data))
return;
+ if (!(action & CPU_TASKS_FROZEN))
+ cmci_reenable();
for (i = 0; i < banks; i++)
wrmsrl(MSR_IA32_MC0_CTL + i*4, bank[i]);
}
case CPU_DOWN_PREPARE:
case CPU_DOWN_PREPARE_FROZEN:
del_timer_sync(t);
- smp_call_function_single(cpu, mce_disable_cpu, NULL, 1);
+ smp_call_function_single(cpu, mce_disable_cpu, &action, 1);
break;
case CPU_DOWN_FAILED:
case CPU_DOWN_FAILED_FROZEN:
t->expires = round_jiffies_relative(jiffies + next_interval);
add_timer_on(t, cpu);
- smp_call_function_single(cpu, mce_reenable_cpu, NULL, 1);
+ smp_call_function_single(cpu, mce_reenable_cpu, &action, 1);
+ break;
+ case CPU_POST_DEAD:
+ /* intentionally ignoring frozen here */
+ cmci_rediscover(cpu);
break;
}
return NOTIFY_OK;
/*
* Intel specific MCE features.
* Copyright 2004 Zwane Mwaikambo <zwane@linuxpower.ca>
+ * Copyright (C) 2008, 2009 Intel Corporation
+ * Author: Andi Kleen
*/
#include <linux/init.h>
#include <asm/hw_irq.h>
#include <asm/idle.h>
#include <asm/therm_throt.h>
+#include <asm/apic.h>
asmlinkage void smp_thermal_interrupt(void)
{
return;
}
+/*
+ * Support for Intel Correct Machine Check Interrupts. This allows
+ * the CPU to raise an interrupt when a corrected machine check happened.
+ * Normally we pick those up using a regular polling timer.
+ * Also supports reliable discovery of shared banks.
+ */
+
+static DEFINE_PER_CPU(mce_banks_t, mce_banks_owned);
+
+/*
+ * cmci_discover_lock protects against parallel discovery attempts
+ * which could race against each other.
+ */
+static DEFINE_SPINLOCK(cmci_discover_lock);
+
+#define CMCI_THRESHOLD 1
+
+static __cpuinit int cmci_supported(int *banks)
+{
+ u64 cap;
+
+ /*
+ * Vendor check is not strictly needed, but the initial
+ * initialization is vendor keyed and this
+ * makes sure none of the backdoors are entered otherwise.
+ */
+ if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL)
+ return 0;
+ if (!cpu_has_apic || lapic_get_maxlvt() < 6)
+ return 0;
+ rdmsrl(MSR_IA32_MCG_CAP, cap);
+ *banks = min_t(unsigned, MAX_NR_BANKS, cap & 0xff);
+ return !!(cap & MCG_CMCI_P);
+}
+
+/*
+ * The interrupt handler. This is called on every event.
+ * Just call the poller directly to log any events.
+ * This could in theory increase the threshold under high load,
+ * but doesn't for now.
+ */
+static void intel_threshold_interrupt(void)
+{
+ machine_check_poll(MCP_TIMESTAMP, &__get_cpu_var(mce_banks_owned));
+ mce_notify_user();
+}
+
+static void print_update(char *type, int *hdr, int num)
+{
+ if (*hdr == 0)
+ printk(KERN_INFO "CPU %d MCA banks", smp_processor_id());
+ *hdr = 1;
+ printk(KERN_CONT " %s:%d", type, num);
+}
+
+/*
+ * Enable CMCI (Corrected Machine Check Interrupt) for available MCE banks
+ * on this CPU. Use the algorithm recommended in the SDM to discover shared
+ * banks.
+ */
+static __cpuinit void cmci_discover(int banks, int boot)
+{
+ unsigned long *owned = (void *)&__get_cpu_var(mce_banks_owned);
+ int hdr = 0;
+ int i;
+
+ spin_lock(&cmci_discover_lock);
+ for (i = 0; i < banks; i++) {
+ u64 val;
+
+ if (test_bit(i, owned))
+ continue;
+
+ rdmsrl(MSR_IA32_MC0_CTL2 + i, val);
+
+ /* Already owned by someone else? */
+ if (val & CMCI_EN) {
+ if (test_and_clear_bit(i, owned) || boot)
+ print_update("SHD", &hdr, i);
+ __clear_bit(i, __get_cpu_var(mce_poll_banks));
+ continue;
+ }
+
+ val |= CMCI_EN | CMCI_THRESHOLD;
+ wrmsrl(MSR_IA32_MC0_CTL2 + i, val);
+ rdmsrl(MSR_IA32_MC0_CTL2 + i, val);
+
+ /* Did the enable bit stick? -- the bank supports CMCI */
+ if (val & CMCI_EN) {
+ if (!test_and_set_bit(i, owned) || boot)
+ print_update("CMCI", &hdr, i);
+ __clear_bit(i, __get_cpu_var(mce_poll_banks));
+ } else {
+ WARN_ON(!test_bit(i, __get_cpu_var(mce_poll_banks)));
+ }
+ }
+ spin_unlock(&cmci_discover_lock);
+ if (hdr)
+ printk(KERN_CONT "\n");
+}
+
+/*
+ * Just in case we missed an event during initialization check
+ * all the CMCI owned banks.
+ */
+__cpuinit void cmci_recheck(void)
+{
+ unsigned long flags;
+ int banks;
+
+ if (!mce_available(¤t_cpu_data) || !cmci_supported(&banks))
+ return;
+ local_irq_save(flags);
+ machine_check_poll(MCP_TIMESTAMP, &__get_cpu_var(mce_banks_owned));
+ local_irq_restore(flags);
+}
+
+/*
+ * Disable CMCI on this CPU for all banks it owns when it goes down.
+ * This allows other CPUs to claim the banks on rediscovery.
+ */
+void __cpuexit cmci_clear(void)
+{
+ int i;
+ int banks;
+ u64 val;
+
+ if (!cmci_supported(&banks))
+ return;
+ spin_lock(&cmci_discover_lock);
+ for (i = 0; i < banks; i++) {
+ if (!test_bit(i, __get_cpu_var(mce_banks_owned)))
+ continue;
+ /* Disable CMCI */
+ rdmsrl(MSR_IA32_MC0_CTL2 + i, val);
+ val &= ~(CMCI_EN|CMCI_THRESHOLD_MASK);
+ wrmsrl(MSR_IA32_MC0_CTL2 + i, val);
+ __clear_bit(i, __get_cpu_var(mce_banks_owned));
+ }
+ spin_unlock(&cmci_discover_lock);
+}
+
+/*
+ * After a CPU went down cycle through all the others and rediscover
+ * Must run in process context.
+ */
+void __cpuexit cmci_rediscover(int dying)
+{
+ int banks;
+ int cpu;
+ cpumask_var_t old;
+
+ if (!cmci_supported(&banks))
+ return;
+ if (!alloc_cpumask_var(&old, GFP_KERNEL))
+ return;
+ cpumask_copy(old, ¤t->cpus_allowed);
+
+ for_each_online_cpu (cpu) {
+ if (cpu == dying)
+ continue;
+ if (set_cpus_allowed_ptr(current, &cpumask_of_cpu(cpu)))
+ continue;
+ /* Recheck banks in case CPUs don't all have the same */
+ if (cmci_supported(&banks))
+ cmci_discover(banks, 0);
+ }
+
+ set_cpus_allowed_ptr(current, old);
+ free_cpumask_var(old);
+}
+
+/*
+ * Reenable CMCI on this CPU in case a CPU down failed.
+ */
+void cmci_reenable(void)
+{
+ int banks;
+ if (cmci_supported(&banks))
+ cmci_discover(banks, 0);
+}
+
+static __cpuinit void intel_init_cmci(void)
+{
+ int banks;
+
+ if (!cmci_supported(&banks))
+ return;
+
+ mce_threshold_vector = intel_threshold_interrupt;
+ cmci_discover(banks, 1);
+ /*
+ * For CPU #0 this runs with still disabled APIC, but that's
+ * ok because only the vector is set up. We still do another
+ * check for the banks later for CPU #0 just to make sure
+ * to not miss any events.
+ */
+ apic_write(APIC_LVTCMCI, THRESHOLD_APIC_VECTOR|APIC_DM_FIXED);
+ cmci_recheck();
+}
+
void mce_intel_feature_init(struct cpuinfo_x86 *c)
{
intel_init_thermal(c);
+ intel_init_cmci();
}