powerpc/kernel/watchdog.c

7  * This uses code from arch/sparc/kernel/nmi.c and kernel/watchdog.c
17 #include <linux/nmi.h>
32 #include <asm/nmi.h>
41  * The local soft-NMI, and the SMP checker.
43  * The soft-NMI checker can detect lockups on the local CPU. When interrupts
47  * watchdog's soft_nmi_interrupt(), which appears to Linux as an NMI
50  * The soft-NMI checker will compare the heartbeat timestamp for this CPU
54  * The limitation of the soft-NMI watchdog is that it does not work when
70  * Some platforms implement true NMI IPIs, which can be used by the SMP
72  * state with the NMI IPI, to get crash/debug data from it. This way the
99  * Try to take the exclusive watchdog action / NMI IPI / printing lock.
131 	hard_irq_disable(); /* Make it soft-NMI safe */  in wd_smp_lock()
163 	 * __wd_nmi_output must be set after we printk from NMI context.  in wd_lockup_ipi()
165 	 * printk from NMI context defers printing to the console to irq_work.  in wd_lockup_ipi()
166 	 * If that NMI was taken in some code that is hard-locked, then irqs  in wd_lockup_ipi()
179 	/* Do not panic from here because that can recurse into NMI IPI layer */  in wd_lockup_ipi()
359 		 * Something has called printk from NMI context. It might be  in watchdog_timer_interrupt()
386 		 * Taking wd_smp_lock here means it is a soft-NMI lock, which  in DEFINE_INTERRUPT_HANDLER_NMI()
587 	pr_info("Set the NMI watchdog timeout factor to %llu%%\n", pct);  in watchdog_hardlockup_set_timeout_pct()