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Commit 05cb007d authored by Andi Kleen's avatar Andi Kleen Committed by Andi Kleen
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[PATCH] x86-64: Use the 32bit wd_ops for 64bit too. 



This mainly removes a lot of code, replacing it with calls into the new 32bit
perfctr-watchdog.c

Signed-off-by: default avatarAndi Kleen <ak@suse.de>
parent 09198e68

arch/x86_64/kernel/Makefile

+3 −1
Original line number Diff line number Diff line
@@ -8,7 +8,8 @@ obj-y := process.o signal.o entry.o traps.o irq.o \ 
		ptrace.o time.o ioport.o ldt.o setup.o i8259.o sys_x86_64.o \

		x8664_ksyms.o i387.o syscall.o vsyscall.o \

		setup64.o bootflag.o e820.o reboot.o quirks.o i8237.o \

		pci-dma.o pci-nommu.o alternative.o hpet.o tsc.o bugs.o

		pci-dma.o pci-nommu.o alternative.o hpet.o tsc.o bugs.o \

		perfctr-watchdog.o



obj-$(CONFIG_STACKTRACE)	+= stacktrace.o

obj-$(CONFIG_X86_MCE)		+= mce.o therm_throt.o
@@ -57,3 +58,4 @@ i8237-y += ../../i386/kernel/i8237.o 
msr-$(subst m,y,$(CONFIG_X86_MSR))  += ../../i386/kernel/msr.o

alternative-y			+= ../../i386/kernel/alternative.o

pcspeaker-y			+= ../../i386/kernel/pcspeaker.o

perfctr-watchdog-y		+= ../../i386/kernel/cpu/perfctr-watchdog.o

arch/x86_64/kernel/nmi.c

+33 −645
Original line number Diff line number Diff line
@@ -27,28 +27,11 @@ 
#include <asm/proto.h>

#include <asm/kdebug.h>

#include <asm/mce.h>

#include <asm/intel_arch_perfmon.h>



int unknown_nmi_panic;

int nmi_watchdog_enabled;

int panic_on_unrecovered_nmi;



/* perfctr_nmi_owner tracks the ownership of the perfctr registers:

 * evtsel_nmi_owner tracks the ownership of the event selection

 * - different performance counters/ event selection may be reserved for

 *   different subsystems this reservation system just tries to coordinate

 *   things a little

 */



/* this number is calculated from Intel's MSR_P4_CRU_ESCR5 register and it's

 * offset from MSR_P4_BSU_ESCR0.  It will be the max for all platforms (for now)

 */

#define NMI_MAX_COUNTER_BITS 66

#define NMI_MAX_COUNTER_LONGS BITS_TO_LONGS(NMI_MAX_COUNTER_BITS)



static DEFINE_PER_CPU(unsigned, perfctr_nmi_owner[NMI_MAX_COUNTER_LONGS]);

static DEFINE_PER_CPU(unsigned, evntsel_nmi_owner[NMI_MAX_COUNTER_LONGS]);



static cpumask_t backtrace_mask = CPU_MASK_NONE;



/* nmi_active:
@@ -63,191 +46,11 @@ int panic_on_timeout; 
unsigned int nmi_watchdog = NMI_DEFAULT;

static unsigned int nmi_hz = HZ;



struct nmi_watchdog_ctlblk {

	int enabled;

	u64 check_bit;

	unsigned int cccr_msr;

	unsigned int perfctr_msr;  /* the MSR to reset in NMI handler */

	unsigned int evntsel_msr;  /* the MSR to select the events to handle */

};

static DEFINE_PER_CPU(struct nmi_watchdog_ctlblk, nmi_watchdog_ctlblk);

static DEFINE_PER_CPU(short, wd_enabled);



/* local prototypes */

static int unknown_nmi_panic_callback(struct pt_regs *regs, int cpu);



/* converts an msr to an appropriate reservation bit */

static inline unsigned int nmi_perfctr_msr_to_bit(unsigned int msr)

{

	/* returns the bit offset of the performance counter register */

	switch (boot_cpu_data.x86_vendor) {

	case X86_VENDOR_AMD:

		return (msr - MSR_K7_PERFCTR0);

	case X86_VENDOR_INTEL:

		if (cpu_has(&boot_cpu_data, X86_FEATURE_ARCH_PERFMON))

			return (msr - MSR_ARCH_PERFMON_PERFCTR0);

		else

			return (msr - MSR_P4_BPU_PERFCTR0);

	}

	return 0;

}



/* converts an msr to an appropriate reservation bit */

static inline unsigned int nmi_evntsel_msr_to_bit(unsigned int msr)

{

	/* returns the bit offset of the event selection register */

	switch (boot_cpu_data.x86_vendor) {

	case X86_VENDOR_AMD:

		return (msr - MSR_K7_EVNTSEL0);

	case X86_VENDOR_INTEL:

		if (cpu_has(&boot_cpu_data, X86_FEATURE_ARCH_PERFMON))

			return (msr - MSR_ARCH_PERFMON_EVENTSEL0);

		else

			return (msr - MSR_P4_BSU_ESCR0);

	}

	return 0;

}



/* checks for a bit availability (hack for oprofile) */

int avail_to_resrv_perfctr_nmi_bit(unsigned int counter)

{

	int cpu;

	BUG_ON(counter > NMI_MAX_COUNTER_BITS);

	for_each_possible_cpu (cpu) {

		if (test_bit(counter, &per_cpu(perfctr_nmi_owner, cpu)))

			return 0;

	}

	return 1;

}



/* checks the an msr for availability */

int avail_to_resrv_perfctr_nmi(unsigned int msr)

{

	unsigned int counter;

	int cpu;



	counter = nmi_perfctr_msr_to_bit(msr);

	BUG_ON(counter > NMI_MAX_COUNTER_BITS);



	for_each_possible_cpu (cpu) {

		if (test_bit(counter, &per_cpu(perfctr_nmi_owner, cpu)))

			return 0;

	}

	return 1;

}



static int __reserve_perfctr_nmi(int cpu, unsigned int msr)

{

	unsigned int counter;

	if (cpu < 0)

		cpu = smp_processor_id();



	counter = nmi_perfctr_msr_to_bit(msr);

	BUG_ON(counter > NMI_MAX_COUNTER_BITS);



	if (!test_and_set_bit(counter, &per_cpu(perfctr_nmi_owner, cpu)))

		return 1;

	return 0;

}



static void __release_perfctr_nmi(int cpu, unsigned int msr)

{

	unsigned int counter;

	if (cpu < 0)

		cpu = smp_processor_id();



	counter = nmi_perfctr_msr_to_bit(msr);

	BUG_ON(counter > NMI_MAX_COUNTER_BITS);



	clear_bit(counter, &per_cpu(perfctr_nmi_owner, cpu));

}



int reserve_perfctr_nmi(unsigned int msr)

{

	int cpu, i;

	for_each_possible_cpu (cpu) {

		if (!__reserve_perfctr_nmi(cpu, msr)) {

			for_each_possible_cpu (i) {

				if (i >= cpu)

					break;

				__release_perfctr_nmi(i, msr);

			}

			return 0;

		}

	}

	return 1;

}



void release_perfctr_nmi(unsigned int msr)

{

	int cpu;

	for_each_possible_cpu (cpu)

		__release_perfctr_nmi(cpu, msr);

}



int __reserve_evntsel_nmi(int cpu, unsigned int msr)

{

	unsigned int counter;

	if (cpu < 0)

		cpu = smp_processor_id();



	counter = nmi_evntsel_msr_to_bit(msr);

	BUG_ON(counter > NMI_MAX_COUNTER_BITS);



	if (!test_and_set_bit(counter, &per_cpu(evntsel_nmi_owner, cpu)[0]))

		return 1;

	return 0;

}



static void __release_evntsel_nmi(int cpu, unsigned int msr)

{

	unsigned int counter;

	if (cpu < 0)

		cpu = smp_processor_id();



	counter = nmi_evntsel_msr_to_bit(msr);

	BUG_ON(counter > NMI_MAX_COUNTER_BITS);



	clear_bit(counter, &per_cpu(evntsel_nmi_owner, cpu)[0]);

}



int reserve_evntsel_nmi(unsigned int msr)

{

	int cpu, i;

	for_each_possible_cpu (cpu) {

		if (!__reserve_evntsel_nmi(cpu, msr)) {

			for_each_possible_cpu (i) {

				if (i >= cpu)

					break;

				__release_evntsel_nmi(i, msr);

			}

			return 0;

		}

	}

	return 1;

}



void release_evntsel_nmi(unsigned int msr)

{

	int cpu;

	for_each_possible_cpu (cpu) {

		__release_evntsel_nmi(cpu, msr);

	}

}



static __cpuinit inline int nmi_known_cpu(void)

{

	switch (boot_cpu_data.x86_vendor) {

	case X86_VENDOR_AMD:

		return boot_cpu_data.x86 == 15 || boot_cpu_data.x86 == 16;

	case X86_VENDOR_INTEL:

		if (cpu_has(&boot_cpu_data, X86_FEATURE_ARCH_PERFMON))

			return 1;

		else

			return (boot_cpu_data.x86 == 15);

	}

	return 0;

}



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

void nmi_watchdog_default(void)

{
@@ -277,23 +80,6 @@ static __init void nmi_cpu_busy(void *data) 
}

#endif



static unsigned int adjust_for_32bit_ctr(unsigned int hz)

{

	unsigned int retval = hz;



	/*

	 * On Intel CPUs with ARCH_PERFMON only 32 bits in the counter

	 * are writable, with higher bits sign extending from bit 31.

	 * So, we can only program the counter with 31 bit values and

	 * 32nd bit should be 1, for 33.. to be 1.

	 * Find the appropriate nmi_hz

	 */

 	if ((((u64)cpu_khz * 1000) / retval) > 0x7fffffffULL) {

		retval = ((u64)cpu_khz * 1000) / 0x7fffffffUL + 1;

	}

	return retval;

}



int __init check_nmi_watchdog (void)

{

	int *counts;
@@ -322,14 +108,14 @@ int __init check_nmi_watchdog (void) 
	mdelay((20*1000)/nmi_hz); // wait 20 ticks



	for_each_online_cpu(cpu) {

		if (!per_cpu(nmi_watchdog_ctlblk, cpu).enabled)

		if (!per_cpu(wd_enabled, cpu))

			continue;

		if (cpu_pda(cpu)->__nmi_count - counts[cpu] <= 5) {

			printk("CPU#%d: NMI appears to be stuck (%d->%d)!\n",

			       cpu,

			       counts[cpu],

			       cpu_pda(cpu)->__nmi_count);

			per_cpu(nmi_watchdog_ctlblk, cpu).enabled = 0;

			per_cpu(wd_enabled, cpu) = 0;

			atomic_dec(&nmi_active);

		}

	}
@@ -344,13 +130,8 @@ int __init check_nmi_watchdog (void) 


	/* now that we know it works we can reduce NMI frequency to

	   something more reasonable; makes a difference in some configs */

	if (nmi_watchdog == NMI_LOCAL_APIC) {

		struct nmi_watchdog_ctlblk *wd = &__get_cpu_var(nmi_watchdog_ctlblk);



		nmi_hz = 1;

	 	if (wd->perfctr_msr == MSR_ARCH_PERFMON_PERFCTR1)

			nmi_hz = adjust_for_32bit_ctr(nmi_hz);

	}

	if (nmi_watchdog == NMI_LOCAL_APIC)

		nmi_hz = lapic_adjust_nmi_hz(1);



	kfree(counts);

	return 0;
@@ -379,57 +160,6 @@ int __init setup_nmi_watchdog(char *str) 


__setup("nmi_watchdog=", setup_nmi_watchdog);



static void disable_lapic_nmi_watchdog(void)

{

	BUG_ON(nmi_watchdog != NMI_LOCAL_APIC);



	if (atomic_read(&nmi_active) <= 0)

		return;



	on_each_cpu(stop_apic_nmi_watchdog, NULL, 0, 1);



	BUG_ON(atomic_read(&nmi_active) != 0);

}



static void enable_lapic_nmi_watchdog(void)

{

	BUG_ON(nmi_watchdog != NMI_LOCAL_APIC);



	/* are we already enabled */

	if (atomic_read(&nmi_active) != 0)

		return;



	/* are we lapic aware */

	if (nmi_known_cpu() <= 0)

		return;



	on_each_cpu(setup_apic_nmi_watchdog, NULL, 0, 1);

	touch_nmi_watchdog();

}



void disable_timer_nmi_watchdog(void)

{

	BUG_ON(nmi_watchdog != NMI_IO_APIC);



	if (atomic_read(&nmi_active) <= 0)

		return;



	disable_irq(0);

	on_each_cpu(stop_apic_nmi_watchdog, NULL, 0, 1);



	BUG_ON(atomic_read(&nmi_active) != 0);

}



void enable_timer_nmi_watchdog(void)

{

	BUG_ON(nmi_watchdog != NMI_IO_APIC);



	if (atomic_read(&nmi_active) == 0) {

		touch_nmi_watchdog();

		on_each_cpu(setup_apic_nmi_watchdog, NULL, 0, 1);

		enable_irq(0);

	}

}



static void __acpi_nmi_disable(void *__unused)

{
@@ -515,275 +245,9 @@ late_initcall(init_lapic_nmi_sysfs); 


#endif	/* CONFIG_PM */



/*

 * Activate the NMI watchdog via the local APIC.

 * Original code written by Keith Owens.

 */



/* Note that these events don't tick when the CPU idles. This means

   the frequency varies with CPU load. */



#define K7_EVNTSEL_ENABLE	(1 << 22)

#define K7_EVNTSEL_INT		(1 << 20)

#define K7_EVNTSEL_OS		(1 << 17)

#define K7_EVNTSEL_USR		(1 << 16)

#define K7_EVENT_CYCLES_PROCESSOR_IS_RUNNING	0x76

#define K7_NMI_EVENT		K7_EVENT_CYCLES_PROCESSOR_IS_RUNNING



static int setup_k7_watchdog(void)

{

	unsigned int perfctr_msr, evntsel_msr;

	unsigned int evntsel;

	struct nmi_watchdog_ctlblk *wd = &__get_cpu_var(nmi_watchdog_ctlblk);



	perfctr_msr = MSR_K7_PERFCTR0;

	evntsel_msr = MSR_K7_EVNTSEL0;

	if (!__reserve_perfctr_nmi(-1, perfctr_msr))

		goto fail;



	if (!__reserve_evntsel_nmi(-1, evntsel_msr))

		goto fail1;



	/* Simulator may not support it */

	if (checking_wrmsrl(evntsel_msr, 0UL))

		goto fail2;

	wrmsrl(perfctr_msr, 0UL);



	evntsel = K7_EVNTSEL_INT

		| K7_EVNTSEL_OS

		| K7_EVNTSEL_USR

		| K7_NMI_EVENT;



	/* setup the timer */

	wrmsr(evntsel_msr, evntsel, 0);

	wrmsrl(perfctr_msr, -((u64)cpu_khz * 1000 / nmi_hz));

	apic_write(APIC_LVTPC, APIC_DM_NMI);

	evntsel |= K7_EVNTSEL_ENABLE;

	wrmsr(evntsel_msr, evntsel, 0);



	wd->perfctr_msr = perfctr_msr;

	wd->evntsel_msr = evntsel_msr;

	wd->cccr_msr = 0;  //unused

	wd->check_bit = 1ULL<<63;

	return 1;

fail2:

	__release_evntsel_nmi(-1, evntsel_msr);

fail1:

	__release_perfctr_nmi(-1, perfctr_msr);

fail:

	return 0;

}



static void stop_k7_watchdog(void)

{

	struct nmi_watchdog_ctlblk *wd = &__get_cpu_var(nmi_watchdog_ctlblk);



	wrmsr(wd->evntsel_msr, 0, 0);



	__release_evntsel_nmi(-1, wd->evntsel_msr);

	__release_perfctr_nmi(-1, wd->perfctr_msr);

}



/* Note that these events don't tick when the CPU idles. This means

   the frequency varies with CPU load. */



#define MSR_P4_MISC_ENABLE_PERF_AVAIL	(1<<7)

#define P4_ESCR_EVENT_SELECT(N)	((N)<<25)

#define P4_ESCR_OS		(1<<3)

#define P4_ESCR_USR		(1<<2)

#define P4_CCCR_OVF_PMI0	(1<<26)

#define P4_CCCR_OVF_PMI1	(1<<27)

#define P4_CCCR_THRESHOLD(N)	((N)<<20)

#define P4_CCCR_COMPLEMENT	(1<<19)

#define P4_CCCR_COMPARE		(1<<18)

#define P4_CCCR_REQUIRED	(3<<16)

#define P4_CCCR_ESCR_SELECT(N)	((N)<<13)

#define P4_CCCR_ENABLE		(1<<12)

#define P4_CCCR_OVF 		(1<<31)

/* Set up IQ_COUNTER0 to behave like a clock, by having IQ_CCCR0 filter

   CRU_ESCR0 (with any non-null event selector) through a complemented

   max threshold. [IA32-Vol3, Section 14.9.9] */



static int setup_p4_watchdog(void)

{

	unsigned int perfctr_msr, evntsel_msr, cccr_msr;

	unsigned int evntsel, cccr_val;

	unsigned int misc_enable, dummy;

	unsigned int ht_num;

	struct nmi_watchdog_ctlblk *wd = &__get_cpu_var(nmi_watchdog_ctlblk);



	rdmsr(MSR_IA32_MISC_ENABLE, misc_enable, dummy);

	if (!(misc_enable & MSR_P4_MISC_ENABLE_PERF_AVAIL))

		return 0;



#ifdef CONFIG_SMP

	/* detect which hyperthread we are on */

	if (smp_num_siblings == 2) {

		unsigned int ebx, apicid;



        	ebx = cpuid_ebx(1);

	        apicid = (ebx >> 24) & 0xff;

        	ht_num = apicid & 1;

	} else

#endif

		ht_num = 0;



	/* performance counters are shared resources

	 * assign each hyperthread its own set

	 * (re-use the ESCR0 register, seems safe

	 * and keeps the cccr_val the same)

	 */

	if (!ht_num) {

		/* logical cpu 0 */

		perfctr_msr = MSR_P4_IQ_PERFCTR0;

		evntsel_msr = MSR_P4_CRU_ESCR0;

		cccr_msr = MSR_P4_IQ_CCCR0;

		cccr_val = P4_CCCR_OVF_PMI0 | P4_CCCR_ESCR_SELECT(4);

	} else {

		/* logical cpu 1 */

		perfctr_msr = MSR_P4_IQ_PERFCTR1;

		evntsel_msr = MSR_P4_CRU_ESCR0;

		cccr_msr = MSR_P4_IQ_CCCR1;

		cccr_val = P4_CCCR_OVF_PMI1 | P4_CCCR_ESCR_SELECT(4);

	}



	if (!__reserve_perfctr_nmi(-1, perfctr_msr))

		goto fail;



	if (!__reserve_evntsel_nmi(-1, evntsel_msr))

		goto fail1;



	evntsel = P4_ESCR_EVENT_SELECT(0x3F)

	 	| P4_ESCR_OS

		| P4_ESCR_USR;



	cccr_val |= P4_CCCR_THRESHOLD(15)

		 | P4_CCCR_COMPLEMENT

		 | P4_CCCR_COMPARE

		 | P4_CCCR_REQUIRED;



	wrmsr(evntsel_msr, evntsel, 0);

	wrmsr(cccr_msr, cccr_val, 0);

	wrmsrl(perfctr_msr, -((u64)cpu_khz * 1000 / nmi_hz));

	apic_write(APIC_LVTPC, APIC_DM_NMI);

	cccr_val |= P4_CCCR_ENABLE;

	wrmsr(cccr_msr, cccr_val, 0);



	wd->perfctr_msr = perfctr_msr;

	wd->evntsel_msr = evntsel_msr;

	wd->cccr_msr = cccr_msr;

	wd->check_bit = 1ULL<<39;

	return 1;

fail1:

	__release_perfctr_nmi(-1, perfctr_msr);

fail:

	return 0;

}



static void stop_p4_watchdog(void)

{

	struct nmi_watchdog_ctlblk *wd = &__get_cpu_var(nmi_watchdog_ctlblk);



	wrmsr(wd->cccr_msr, 0, 0);

	wrmsr(wd->evntsel_msr, 0, 0);



	__release_evntsel_nmi(-1, wd->evntsel_msr);

	__release_perfctr_nmi(-1, wd->perfctr_msr);

}



#define ARCH_PERFMON_NMI_EVENT_SEL	ARCH_PERFMON_UNHALTED_CORE_CYCLES_SEL

#define ARCH_PERFMON_NMI_EVENT_UMASK	ARCH_PERFMON_UNHALTED_CORE_CYCLES_UMASK



static int setup_intel_arch_watchdog(void)

{

	unsigned int ebx;

	union cpuid10_eax eax;

	unsigned int unused;

	unsigned int perfctr_msr, evntsel_msr;

	unsigned int evntsel;

	struct nmi_watchdog_ctlblk *wd = &__get_cpu_var(nmi_watchdog_ctlblk);



	/*

	 * Check whether the Architectural PerfMon supports

	 * Unhalted Core Cycles Event or not.

	 * NOTE: Corresponding bit = 0 in ebx indicates event present.

	 */

	cpuid(10, &(eax.full), &ebx, &unused, &unused);

	if ((eax.split.mask_length < (ARCH_PERFMON_UNHALTED_CORE_CYCLES_INDEX+1)) ||

	    (ebx & ARCH_PERFMON_UNHALTED_CORE_CYCLES_PRESENT))

		goto fail;



	perfctr_msr = MSR_ARCH_PERFMON_PERFCTR1;

	evntsel_msr = MSR_ARCH_PERFMON_EVENTSEL1;



	if (!__reserve_perfctr_nmi(-1, perfctr_msr))

		goto fail;



	if (!__reserve_evntsel_nmi(-1, evntsel_msr))

		goto fail1;



	wrmsrl(perfctr_msr, 0UL);



	evntsel = ARCH_PERFMON_EVENTSEL_INT

		| ARCH_PERFMON_EVENTSEL_OS

		| ARCH_PERFMON_EVENTSEL_USR

		| ARCH_PERFMON_NMI_EVENT_SEL

		| ARCH_PERFMON_NMI_EVENT_UMASK;



	/* setup the timer */

	wrmsr(evntsel_msr, evntsel, 0);



	nmi_hz = adjust_for_32bit_ctr(nmi_hz);

	wrmsr(perfctr_msr, (u32)(-((u64)cpu_khz * 1000 / nmi_hz)), 0);



	apic_write(APIC_LVTPC, APIC_DM_NMI);

	evntsel |= ARCH_PERFMON_EVENTSEL0_ENABLE;

	wrmsr(evntsel_msr, evntsel, 0);



	wd->perfctr_msr = perfctr_msr;

	wd->evntsel_msr = evntsel_msr;

	wd->cccr_msr = 0;  //unused

	wd->check_bit = 1ULL << (eax.split.bit_width - 1);

	return 1;

fail1:

	__release_perfctr_nmi(-1, perfctr_msr);

fail:

	return 0;

}



static void stop_intel_arch_watchdog(void)

{

	unsigned int ebx;

	union cpuid10_eax eax;

	unsigned int unused;

	struct nmi_watchdog_ctlblk *wd = &__get_cpu_var(nmi_watchdog_ctlblk);



	/*

	 * Check whether the Architectural PerfMon supports

	 * Unhalted Core Cycles Event or not.

	 * NOTE: Corresponding bit = 0 in ebx indicates event present.

	 */

	cpuid(10, &(eax.full), &ebx, &unused, &unused);

	if ((eax.split.mask_length < (ARCH_PERFMON_UNHALTED_CORE_CYCLES_INDEX+1)) ||

	    (ebx & ARCH_PERFMON_UNHALTED_CORE_CYCLES_PRESENT))

		return;



	wrmsr(wd->evntsel_msr, 0, 0);



	__release_evntsel_nmi(-1, wd->evntsel_msr);

	__release_perfctr_nmi(-1, wd->perfctr_msr);

}



void setup_apic_nmi_watchdog(void *unused)

{

	struct nmi_watchdog_ctlblk *wd = &__get_cpu_var(nmi_watchdog_ctlblk);



	/* only support LOCAL and IO APICs for now */

	if ((nmi_watchdog != NMI_LOCAL_APIC) &&

	    (nmi_watchdog != NMI_IO_APIC))

	    	return;



	if (wd->enabled == 1)

	if (__get_cpu_var(wd_enabled) == 1)

		return;



	/* cheap hack to support suspend/resume */
@@ -791,62 +255,31 @@ void setup_apic_nmi_watchdog(void *unused) 
	if ((smp_processor_id() != 0) && (atomic_read(&nmi_active) <= 0))

		return;



	if (nmi_watchdog == NMI_LOCAL_APIC) {

		switch (boot_cpu_data.x86_vendor) {

		case X86_VENDOR_AMD:

			if (strstr(boot_cpu_data.x86_model_id, "Screwdriver"))

				return;

			if (!setup_k7_watchdog())

				return;

			break;

		case X86_VENDOR_INTEL:

			if (cpu_has(&boot_cpu_data, X86_FEATURE_ARCH_PERFMON)) {

				if (!setup_intel_arch_watchdog())

					return;

				break;

			}

			if (!setup_p4_watchdog())

				return;

			break;

		default:

	switch (nmi_watchdog) {

	case NMI_LOCAL_APIC:

		__get_cpu_var(wd_enabled) = 1;

		if (lapic_watchdog_init(nmi_hz) < 0) {

			__get_cpu_var(wd_enabled) = 0;

			return;

		}

	}

	wd->enabled = 1;

		/* FALL THROUGH */

	case NMI_IO_APIC:

		__get_cpu_var(wd_enabled) = 1;

		atomic_inc(&nmi_active);

	}

}



void stop_apic_nmi_watchdog(void *unused)

{

	struct nmi_watchdog_ctlblk *wd = &__get_cpu_var(nmi_watchdog_ctlblk);



	/* only support LOCAL and IO APICs for now */

	if ((nmi_watchdog != NMI_LOCAL_APIC) &&

	    (nmi_watchdog != NMI_IO_APIC))

	    	return;



	if (wd->enabled == 0)

	if (__get_cpu_var(wd_enabled) == 0)

		return;



	if (nmi_watchdog == NMI_LOCAL_APIC) {

		switch (boot_cpu_data.x86_vendor) {

		case X86_VENDOR_AMD:

			if (strstr(boot_cpu_data.x86_model_id, "Screwdriver"))

				return;

			stop_k7_watchdog();

			break;

		case X86_VENDOR_INTEL:

			if (cpu_has(&boot_cpu_data, X86_FEATURE_ARCH_PERFMON)) {

				stop_intel_arch_watchdog();

				break;

			}

			stop_p4_watchdog();

			break;

		default:

			return;

		}

	}

	wd->enabled = 0;

	if (nmi_watchdog == NMI_LOCAL_APIC)

		lapic_watchdog_stop();

	__get_cpu_var(wd_enabled) = 0;

	atomic_dec(&nmi_active);

}
@@ -885,8 +318,6 @@ int __kprobes nmi_watchdog_tick(struct pt_regs * regs, unsigned reason) 
	int sum;

	int touched = 0;

	int cpu = smp_processor_id();

	struct nmi_watchdog_ctlblk *wd = &__get_cpu_var(nmi_watchdog_ctlblk);

	u64 dummy;

	int rc = 0;



	/* check for other users first */
@@ -934,55 +365,20 @@ int __kprobes nmi_watchdog_tick(struct pt_regs * regs, unsigned reason) 
	}



	/* see if the nmi watchdog went off */

	if (wd->enabled) {

		if (nmi_watchdog == NMI_LOCAL_APIC) {

			rdmsrl(wd->perfctr_msr, dummy);

			if (dummy & wd->check_bit){

				/* this wasn't a watchdog timer interrupt */

				goto done;

			}



			/* only Intel uses the cccr msr */

	 		if (wd->cccr_msr != 0) {

	 			/*

	 			 * P4 quirks:

	 			 * - An overflown perfctr will assert its interrupt

	 			 *   until the OVF flag in its CCCR is cleared.

	 			 * - LVTPC is masked on interrupt and must be

	 			 *   unmasked by the LVTPC handler.

	 			 */

				rdmsrl(wd->cccr_msr, dummy);

				dummy &= ~P4_CCCR_OVF;

	 			wrmsrl(wd->cccr_msr, dummy);

	 			apic_write(APIC_LVTPC, APIC_DM_NMI);

				/* start the cycle over again */

				wrmsrl(wd->perfctr_msr,

				       -((u64)cpu_khz * 1000 / nmi_hz));

	 		} else if (wd->perfctr_msr == MSR_ARCH_PERFMON_PERFCTR1) {

				/*

				 * ArchPerfom/Core Duo needs to re-unmask

				 * the apic vector

				 */

				apic_write(APIC_LVTPC, APIC_DM_NMI);

				/* ARCH_PERFMON has 32 bit counter writes */

				wrmsr(wd->perfctr_msr,

				     (u32)(-((u64)cpu_khz * 1000 / nmi_hz)), 0);

			} else {

				/* start the cycle over again */

				wrmsrl(wd->perfctr_msr,

				       -((u64)cpu_khz * 1000 / nmi_hz));

			}

			rc = 1;

		} else 	if (nmi_watchdog == NMI_IO_APIC) {

	if (!__get_cpu_var(wd_enabled))

		return rc;

	switch (nmi_watchdog) {

	case NMI_LOCAL_APIC:

		rc |= lapic_wd_event(nmi_hz);

		break;

	case NMI_IO_APIC:

		/* don't know how to accurately check for this.

		 * just assume it was a watchdog timer interrupt

		 * This matches the old behaviour.

		 */

		rc = 1;

		} else

			printk(KERN_WARNING "Unknown enabled NMI hardware?!\n");

		break;

	}

done:

	return rc;

}
@@ -1067,12 +463,4 @@ void __trigger_all_cpu_backtrace(void) 


EXPORT_SYMBOL(nmi_active);

EXPORT_SYMBOL(nmi_watchdog);

EXPORT_SYMBOL(avail_to_resrv_perfctr_nmi);

EXPORT_SYMBOL(avail_to_resrv_perfctr_nmi_bit);

EXPORT_SYMBOL(reserve_perfctr_nmi);

EXPORT_SYMBOL(release_perfctr_nmi);

EXPORT_SYMBOL(reserve_evntsel_nmi);

EXPORT_SYMBOL(release_evntsel_nmi);

EXPORT_SYMBOL(disable_timer_nmi_watchdog);

EXPORT_SYMBOL(enable_timer_nmi_watchdog);

EXPORT_SYMBOL(touch_nmi_watchdog);

include/asm-x86_64/nmi.h

+9 −0
Original line number Diff line number Diff line
@@ -80,4 +80,13 @@ extern int unknown_nmi_panic; 
void __trigger_all_cpu_backtrace(void);

#define trigger_all_cpu_backtrace() __trigger_all_cpu_backtrace()





void lapic_watchdog_stop(void);

int lapic_watchdog_init(unsigned nmi_hz);

int lapic_wd_event(unsigned nmi_hz);

unsigned lapic_adjust_nmi_hz(unsigned hz);

int lapic_watchdog_ok(void);

void disable_lapic_nmi_watchdog(void);

void enable_lapic_nmi_watchdog(void);



#endif /* ASM_NMI_H */