#include <asm/irq_regs.h>
#include <linux/perf_event.h>
-int watchdog_enabled;
+int watchdog_enabled = 1;
int __read_mostly softlockup_thresh = 60;
static DEFINE_PER_CPU(unsigned long, watchdog_touch_ts);
static DEFINE_PER_CPU(struct perf_event *, watchdog_ev);
#endif
-static int no_watchdog;
-
-
/* boot commands */
/*
* Should we panic when a soft-lockup or hard-lockup occurs:
if (!strncmp(str, "panic", 5))
hardlockup_panic = 1;
else if (!strncmp(str, "0", 1))
- no_watchdog = 1;
+ watchdog_enabled = 0;
return 1;
}
__setup("nmi_watchdog=", hardlockup_panic_setup);
static int __init nowatchdog_setup(char *str)
{
- no_watchdog = 1;
+ watchdog_enabled = 0;
return 1;
}
__setup("nowatchdog", nowatchdog_setup);
/* deprecated */
static int __init nosoftlockup_setup(char *str)
{
- no_watchdog = 1;
+ watchdog_enabled = 0;
return 1;
}
__setup("nosoftlockup", nosoftlockup_setup);
goto out_save;
}
- printk(KERN_ERR "NMI watchdog disabled for cpu%i: unable to create perf event: %ld\n",
- cpu, PTR_ERR(event));
+
+ /* vary the KERN level based on the returned errno */
+ if (PTR_ERR(event) == -EOPNOTSUPP)
+ printk(KERN_INFO "NMI watchdog disabled (cpu%i): not supported (no LAPIC?)\n", cpu);
+ else if (PTR_ERR(event) == -ENOENT)
+ printk(KERN_WARNING "NMI watchdog disabled (cpu%i): hardware events not enabled\n", cpu);
+ else
+ printk(KERN_ERR "NMI watchdog disabled (cpu%i): unable to create perf event: %ld\n", cpu, PTR_ERR(event));
return PTR_ERR(event);
/* success path */
wake_up_process(p);
}
- /* if any cpu succeeds, watchdog is considered enabled for the system */
- watchdog_enabled = 1;
-
return 0;
}
static void watchdog_enable_all_cpus(void)
{
int cpu;
- int result = 0;
+
+ watchdog_enabled = 0;
for_each_online_cpu(cpu)
- result += watchdog_enable(cpu);
+ if (!watchdog_enable(cpu))
+ /* if any cpu succeeds, watchdog is considered
+ enabled for the system */
+ watchdog_enabled = 1;
- if (result)
+ if (!watchdog_enabled)
printk(KERN_ERR "watchdog: failed to be enabled on some cpus\n");
}
{
int cpu;
- if (no_watchdog)
- return;
-
for_each_online_cpu(cpu)
watchdog_disable(cpu);
{
proc_dointvec(table, write, buffer, length, ppos);
- if (watchdog_enabled)
- watchdog_enable_all_cpus();
- else
- watchdog_disable_all_cpus();
+ if (write) {
+ if (watchdog_enabled)
+ watchdog_enable_all_cpus();
+ else
+ watchdog_disable_all_cpus();
+ }
return 0;
}
break;
case CPU_ONLINE:
case CPU_ONLINE_FROZEN:
- err = watchdog_enable(hotcpu);
+ if (watchdog_enabled)
+ err = watchdog_enable(hotcpu);
break;
#ifdef CONFIG_HOTPLUG_CPU
case CPU_UP_CANCELED:
void *cpu = (void *)(long)smp_processor_id();
int err;
- if (no_watchdog)
- return;
-
err = cpu_callback(&cpu_nfb, CPU_UP_PREPARE, cpu);
WARN_ON(notifier_to_errno(err));