#include <linux/cpu.h>
#include <linux/percpu.h>
#include <linux/ctype.h>
+#include <linux/kmod.h>
#include <asm/processor.h>
#include <asm/msr.h>
#include <asm/mce.h>
static int notify_user;
static int rip_msr;
static int mce_bootlog = 1;
+static atomic_t mce_events;
+
+static char trigger[128];
+static char *trigger_argv[2] = { trigger, NULL };
/*
* Lockless MCE logging infrastructure.
void mce_log(struct mce *mce)
{
unsigned next, entry;
+ atomic_inc(&mce_events);
mce->finished = 0;
wmb();
for (;;) {
}
}
+static void do_mce_trigger(void)
+{
+ static atomic_t mce_logged;
+ int events = atomic_read(&mce_events);
+ if (events != atomic_read(&mce_logged) && trigger[0]) {
+ /* Small race window, but should be harmless. */
+ atomic_set(&mce_logged, events);
+ call_usermodehelper(trigger, trigger_argv, NULL, -1);
+ }
+}
+
/*
* The actual machine check handler
*/
}
/* Never do anything final in the polling timer */
- if (!regs)
+ if (!regs) {
+ /* Normal interrupt context here. Call trigger for any new
+ events. */
+ do_mce_trigger();
goto out;
+ }
/* If we didn't find an uncorrectable error, pick
the last one (shouldn't happen, just being safe). */
#endif /* CONFIG_X86_MCE_INTEL */
/*
- * Periodic polling timer for "silent" machine check errors.
+ * Periodic polling timer for "silent" machine check errors. If the
+ * poller finds an MCE, poll 2x faster. When the poller finds no more
+ * errors, poll 2x slower (up to check_interval seconds).
*/
static int check_interval = 5 * 60; /* 5 minutes */
+static int next_interval; /* in jiffies */
static void mcheck_timer(struct work_struct *work);
static DECLARE_DELAYED_WORK(mcheck_work, mcheck_timer);
static void mcheck_timer(struct work_struct *work)
{
on_each_cpu(mcheck_check_cpu, NULL, 1, 1);
- schedule_delayed_work(&mcheck_work, check_interval * HZ);
/*
* It's ok to read stale data here for notify_user and
* writes.
*/
if (notify_user && console_logged) {
+ static unsigned long last_print;
+ unsigned long now = jiffies;
+
+ /* if we logged an MCE, reduce the polling interval */
+ next_interval = max(next_interval/2, HZ/100);
notify_user = 0;
clear_bit(0, &console_logged);
- printk(KERN_INFO "Machine check events logged\n");
+ if (time_after_eq(now, last_print + (check_interval*HZ))) {
+ last_print = now;
+ printk(KERN_INFO "Machine check events logged\n");
+ }
+ } else {
+ next_interval = min(next_interval*2, check_interval*HZ);
}
+
+ schedule_delayed_work(&mcheck_work, next_interval);
}
static __init int periodic_mcheck_init(void)
{
- if (check_interval)
- schedule_delayed_work(&mcheck_work, check_interval*HZ);
+ next_interval = check_interval * HZ;
+ if (next_interval)
+ schedule_delayed_work(&mcheck_work, next_interval);
return 0;
}
__initcall(periodic_mcheck_init);
}
}
-static struct file_operations mce_chrdev_ops = {
+static const struct file_operations mce_chrdev_ops = {
.read = mce_read,
.ioctl = mce_ioctl,
};
/* Reinit MCEs after user configuration changes */
static void mce_restart(void)
{
- if (check_interval)
+ if (next_interval)
cancel_delayed_work(&mcheck_work);
/* Timer race is harmless here */
on_each_cpu(mce_init, NULL, 1, 1);
- if (check_interval)
- schedule_delayed_work(&mcheck_work, check_interval*HZ);
+ next_interval = check_interval * HZ;
+ if (next_interval)
+ schedule_delayed_work(&mcheck_work, next_interval);
}
static struct sysdev_class mce_sysclass = {
} \
static SYSDEV_ATTR(name, 0644, show_ ## name, set_ ## name);
+/* TBD should generate these dynamically based on number of available banks */
ACCESSOR(bank0ctl,bank[0],mce_restart())
ACCESSOR(bank1ctl,bank[1],mce_restart())
ACCESSOR(bank2ctl,bank[2],mce_restart())
ACCESSOR(bank3ctl,bank[3],mce_restart())
ACCESSOR(bank4ctl,bank[4],mce_restart())
ACCESSOR(bank5ctl,bank[5],mce_restart())
-static struct sysdev_attribute * bank_attributes[NR_BANKS] = {
- &attr_bank0ctl, &attr_bank1ctl, &attr_bank2ctl,
- &attr_bank3ctl, &attr_bank4ctl, &attr_bank5ctl};
+
+static ssize_t show_trigger(struct sys_device *s, char *buf)
+{
+ strcpy(buf, trigger);
+ strcat(buf, "\n");
+ return strlen(trigger) + 1;
+}
+
+static ssize_t set_trigger(struct sys_device *s,const char *buf,size_t siz)
+{
+ char *p;
+ int len;
+ strncpy(trigger, buf, sizeof(trigger));
+ trigger[sizeof(trigger)-1] = 0;
+ len = strlen(trigger);
+ p = strchr(trigger, '\n');
+ if (*p) *p = 0;
+ return len;
+}
+
+static SYSDEV_ATTR(trigger, 0644, show_trigger, set_trigger);
ACCESSOR(tolerant,tolerant,)
ACCESSOR(check_interval,check_interval,mce_restart())
+static struct sysdev_attribute *mce_attributes[] = {
+ &attr_bank0ctl, &attr_bank1ctl, &attr_bank2ctl,
+ &attr_bank3ctl, &attr_bank4ctl, &attr_bank5ctl,
+ &attr_tolerant, &attr_check_interval, &attr_trigger,
+ NULL
+};
/* Per cpu sysdev init. All of the cpus still share the same ctl bank */
static __cpuinit int mce_create_device(unsigned int cpu)
err = sysdev_register(&per_cpu(device_mce,cpu));
if (!err) {
- for (i = 0; i < banks; i++)
+ for (i = 0; mce_attributes[i]; i++)
sysdev_create_file(&per_cpu(device_mce,cpu),
- bank_attributes[i]);
- sysdev_create_file(&per_cpu(device_mce,cpu), &attr_tolerant);
- sysdev_create_file(&per_cpu(device_mce,cpu), &attr_check_interval);
+ mce_attributes[i]);
}
return err;
}
{
int i;
- for (i = 0; i < banks; i++)
+ for (i = 0; mce_attributes[i]; i++)
sysdev_remove_file(&per_cpu(device_mce,cpu),
- bank_attributes[i]);
- sysdev_remove_file(&per_cpu(device_mce,cpu), &attr_tolerant);
- sysdev_remove_file(&per_cpu(device_mce,cpu), &attr_check_interval);
+ mce_attributes[i]);
sysdev_unregister(&per_cpu(device_mce,cpu));
memset(&per_cpu(device_mce, cpu).kobj, 0, sizeof(struct kobject));
}