#include <linux/percpu.h>
#include <linux/ctype.h>
#include <linux/kmod.h>
+#include <linux/kdebug.h>
#include <asm/processor.h>
#include <asm/msr.h>
#include <asm/mce.h>
-#include <asm/kdebug.h>
#include <asm/uaccess.h>
#include <asm/smp.h>
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);
+ call_usermodehelper(trigger, trigger_argv, NULL, UMH_NO_WAIT);
}
}
#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);
* Character device to read and clear the MCE log.
*/
+static DEFINE_SPINLOCK(mce_state_lock);
+static int open_count; /* #times opened */
+static int open_exclu; /* already open exclusive? */
+
+static int mce_open(struct inode *inode, struct file *file)
+{
+ spin_lock(&mce_state_lock);
+
+ if (open_exclu || (open_count && (file->f_flags & O_EXCL))) {
+ spin_unlock(&mce_state_lock);
+ return -EBUSY;
+ }
+
+ if (file->f_flags & O_EXCL)
+ open_exclu = 1;
+ open_count++;
+
+ spin_unlock(&mce_state_lock);
+
+ return 0;
+}
+
+static int mce_release(struct inode *inode, struct file *file)
+{
+ spin_lock(&mce_state_lock);
+
+ open_count--;
+ open_exclu = 0;
+
+ spin_unlock(&mce_state_lock);
+
+ return 0;
+}
+
static void collect_tscs(void *data)
{
unsigned long *cpu_tsc = (unsigned long *)data;
for (i = 0; i < next; i++) {
unsigned long start = jiffies;
while (!mcelog.entry[i].finished) {
- if (!time_before(jiffies, start + 2)) {
+ if (time_after_eq(jiffies, start + 2)) {
memset(mcelog.entry + i,0, sizeof(struct mce));
- continue;
+ goto timeout;
}
cpu_relax();
}
smp_rmb();
err |= copy_to_user(buf, mcelog.entry + i, sizeof(struct mce));
buf += sizeof(struct mce);
+ timeout:
+ ;
}
memset(mcelog.entry, 0, next * sizeof(struct mce));
}
static const struct file_operations mce_chrdev_ops = {
+ .open = mce_open,
+ .release = mce_release,
.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 = {
switch (action) {
case CPU_ONLINE:
+ case CPU_ONLINE_FROZEN:
mce_create_device(cpu);
break;
case CPU_DEAD:
+ case CPU_DEAD_FROZEN:
mce_remove_device(cpu);
break;
}