Commit c376d454 authored by Cyrill Gorcunov's avatar Cyrill Gorcunov Committed by Ingo Molnar
Browse files

x86: nmi_watchdog - use NMI_NONE by default 



There is no need to keep NMI_DISABLED definition and use it
for nmi_watchdog by default. Here is the point why:

- IO-APIC and APIC chips are programmed for nmi_watchdog support at very
  early stage of kernel booting and not having nmi_watchdog specified as
  boot option lead only to nmi_watchdog becomes to NMI_NONE anyway
- enable nmi_watchdog thru /proc/sys/kernel/nmi if it was not specified at
  boot is not possible too (even having this sysfs entry)

Signed-off-by: default avatarCyrill Gorcunov <gorcunov@gmail.com>
Cc: macro@linux-mips.org
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent 2b6addad

arch/x86/kernel/apic_64.c

+0 −1
Original line number Diff line number Diff line
@@ -826,7 +826,6 @@ static void __cpuinit lapic_setup_esr(void) 
void __cpuinit end_local_APIC_setup(void)

{

	lapic_setup_esr();

	nmi_watchdog_default();

	setup_apic_nmi_watchdog(NULL);

	apic_pm_activate();

}

arch/x86/kernel/io_apic_64.c

+0 −2
Original line number Diff line number Diff line
@@ -1729,7 +1729,6 @@ static inline void __init check_timer(void) 
		}

		unmask_IO_APIC_irq(0);

		if (!no_timer_check && timer_irq_works()) {

			nmi_watchdog_default();

			if (nmi_watchdog == NMI_IO_APIC) {

				setup_nmi();

				enable_8259A_irq(0);
@@ -1758,7 +1757,6 @@ static inline void __init check_timer(void) 
		if (timer_irq_works()) {

			apic_printk(APIC_VERBOSE," works.\n");

			timer_through_8259 = 1;

			nmi_watchdog_default();

			if (nmi_watchdog == NMI_IO_APIC) {

				disable_8259A_irq(0);

				setup_nmi();

arch/x86/kernel/nmi.c

+3 −23
Original line number Diff line number Diff line
@@ -52,7 +52,7 @@ static cpumask_t backtrace_mask = CPU_MASK_NONE; 
atomic_t nmi_active = ATOMIC_INIT(0);		/* oprofile uses this */

EXPORT_SYMBOL(nmi_active);



unsigned int nmi_watchdog = NMI_DEFAULT;

unsigned int nmi_watchdog = NMI_NONE;

EXPORT_SYMBOL(nmi_watchdog);



static int panic_on_timeout;
@@ -92,14 +92,6 @@ static inline unsigned int get_timer_irqs(int cpu) 
#endif

}



/* Run after command line and cpu_init init, but before all other checks */

void nmi_watchdog_default(void)

{

	if (nmi_watchdog != NMI_DEFAULT)

		return;

	nmi_watchdog = NMI_NONE;

}



#ifdef CONFIG_SMP

/*

 * The performance counters used by NMI_LOCAL_APIC don't trigger when
@@ -127,7 +119,7 @@ int __init check_nmi_watchdog(void) 
	unsigned int *prev_nmi_count;

	int cpu;



	if (nmi_watchdog == NMI_NONE || nmi_watchdog == NMI_DISABLED)

	if (nmi_watchdog == NMI_NONE)

		return 0;



	if (!atomic_read(&nmi_active))
@@ -482,24 +474,12 @@ int proc_nmi_enabled(struct ctl_table *table, int write, struct file *file, 
	if (!!old_state == !!nmi_watchdog_enabled)

		return 0;



	if (atomic_read(&nmi_active) < 0 || nmi_watchdog == NMI_DISABLED) {

	if (atomic_read(&nmi_active) < 0 || nmi_watchdog == NMI_NONE) {

		printk(KERN_WARNING

			"NMI watchdog is permanently disabled\n");

		return -EIO;

	}



	/* if nmi_watchdog is not set yet, then set it */

	nmi_watchdog_default();



#ifdef CONFIG_X86_32

	if (nmi_watchdog == NMI_NONE) {

		if (lapic_watchdog_ok())

			nmi_watchdog = NMI_LOCAL_APIC;

		else

			nmi_watchdog = NMI_IO_APIC;

	}

#endif



	if (nmi_watchdog == NMI_LOCAL_APIC) {

		if (nmi_watchdog_enabled)

			enable_lapic_nmi_watchdog();

arch/x86/kernel/smpboot.c

+0 −1
Original line number Diff line number Diff line
@@ -1139,7 +1139,6 @@ static void __init smp_cpu_index_default(void) 
void __init native_smp_prepare_cpus(unsigned int max_cpus)

{

	preempt_disable();

	nmi_watchdog_default();

	smp_cpu_index_default();

	current_cpu_data = boot_cpu_data;

	cpu_callin_map = cpumask_of_cpu(0);

include/asm-x86/nmi.h

+0 −3
Original line number Diff line number Diff line
@@ -20,7 +20,6 @@ extern void default_do_nmi(struct pt_regs *); 
#endif



extern void die_nmi(char *str, struct pt_regs *regs, int do_panic);

extern void nmi_watchdog_default(void);

extern int check_nmi_watchdog(void);

extern int nmi_watchdog_enabled;

extern int avail_to_resrv_perfctr_nmi_bit(unsigned int);
@@ -38,12 +37,10 @@ extern int nmi_watchdog_tick(struct pt_regs *regs, unsigned reason); 


extern atomic_t nmi_active;

extern unsigned int nmi_watchdog;

#define NMI_DISABLED    -1

#define NMI_NONE	0

#define NMI_IO_APIC	1

#define NMI_LOCAL_APIC	2

#define NMI_INVALID	3

#define NMI_DEFAULT	NMI_DISABLED



struct ctl_table;

struct file;

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