On some configs the following build error triggers: arch/x86/kernel/apic/hw_nmi.c:35: error: 'apic' undeclared (first use in this function) arch/x86/kernel/apic/hw_nmi.c:35: error: (Each undeclared identifier is reported only once arch/x86/kernel/apic/hw_nmi.c:35: error: for each function it appears in.) Because asm/apic.h was only included implicitly. Include it explicitly. Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Don Zickus <dzickus@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Cyrill Gorcunov <gorcunov@gmail.com> LKML-Reference: <1273713674-8434-1-git-send-regression-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
		
			
				
	
	
		
			107 lines
		
	
	
	
		
			2.6 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			107 lines
		
	
	
	
		
			2.6 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
/*
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 *  HW NMI watchdog support
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 *
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 *  started by Don Zickus, Copyright (C) 2010 Red Hat, Inc.
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 *
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 *  Arch specific calls to support NMI watchdog
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 *
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 *  Bits copied from original nmi.c file
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 *
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 */
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#include <asm/apic.h>
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#include <linux/cpumask.h>
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#include <linux/kdebug.h>
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#include <linux/notifier.h>
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#include <linux/kprobes.h>
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#include <linux/nmi.h>
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#include <linux/module.h>
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/* For reliability, we're prepared to waste bits here. */
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static DECLARE_BITMAP(backtrace_mask, NR_CPUS) __read_mostly;
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u64 hw_nmi_get_sample_period(void)
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{
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	return (u64)(cpu_khz) * 1000 * 60;
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}
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#ifdef ARCH_HAS_NMI_WATCHDOG
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void arch_trigger_all_cpu_backtrace(void)
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{
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	int i;
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	cpumask_copy(to_cpumask(backtrace_mask), cpu_online_mask);
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	printk(KERN_INFO "sending NMI to all CPUs:\n");
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	apic->send_IPI_all(NMI_VECTOR);
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	/* Wait for up to 10 seconds for all CPUs to do the backtrace */
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	for (i = 0; i < 10 * 1000; i++) {
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		if (cpumask_empty(to_cpumask(backtrace_mask)))
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			break;
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		mdelay(1);
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	}
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}
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static int __kprobes
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arch_trigger_all_cpu_backtrace_handler(struct notifier_block *self,
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			 unsigned long cmd, void *__args)
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{
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	struct die_args *args = __args;
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	struct pt_regs *regs;
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	int cpu = smp_processor_id();
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	switch (cmd) {
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	case DIE_NMI:
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	case DIE_NMI_IPI:
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		break;
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	default:
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		return NOTIFY_DONE;
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	}
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	regs = args->regs;
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	if (cpumask_test_cpu(cpu, to_cpumask(backtrace_mask))) {
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		static arch_spinlock_t lock = __ARCH_SPIN_LOCK_UNLOCKED;
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		arch_spin_lock(&lock);
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		printk(KERN_WARNING "NMI backtrace for cpu %d\n", cpu);
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		show_regs(regs);
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		dump_stack();
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		arch_spin_unlock(&lock);
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		cpumask_clear_cpu(cpu, to_cpumask(backtrace_mask));
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		return NOTIFY_STOP;
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	}
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	return NOTIFY_DONE;
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}
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static __read_mostly struct notifier_block backtrace_notifier = {
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	.notifier_call          = arch_trigger_all_cpu_backtrace_handler,
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	.next                   = NULL,
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	.priority               = 1
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};
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static int __init register_trigger_all_cpu_backtrace(void)
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{
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	register_die_notifier(&backtrace_notifier);
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	return 0;
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}
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early_initcall(register_trigger_all_cpu_backtrace);
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#endif
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/* STUB calls to mimic old nmi_watchdog behaviour */
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#if defined(CONFIG_X86_LOCAL_APIC)
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unsigned int nmi_watchdog = NMI_NONE;
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EXPORT_SYMBOL(nmi_watchdog);
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void acpi_nmi_enable(void) { return; }
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void acpi_nmi_disable(void) { return; }
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#endif
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atomic_t nmi_active = ATOMIC_INIT(0);           /* oprofile uses this */
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EXPORT_SYMBOL(nmi_active);
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int unknown_nmi_panic;
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void cpu_nmi_set_wd_enabled(void) { return; }
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void stop_apic_nmi_watchdog(void *unused) { return; }
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void setup_apic_nmi_watchdog(void *unused) { return; }
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int __init check_nmi_watchdog(void) { return 0; }
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