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Commit b7471c6d authored by Don Zickus's avatar Don Zickus Committed by Andi Kleen
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[PATCH] i386: Add SMP support on i386 to reservation framework



This patch includes the changes to make the nmi watchdog on i386 SMP aware.
A bunch of code was moved around to make it simpler to read.  In addition,
it is now possible to determine if a particular NMI was the result of the
watchdog or not.  This feature allows the kernel to filter out unknown NMIs
easier.

Signed-off-by: default avatarDon Zickus <dzickus@redhat.com>
Signed-off-by: default avatarAndi Kleen <ak@suse.de>
parent f2802e7f
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+1 −2
Original line number Original line Diff line number Diff line
@@ -586,8 +586,7 @@ void __devinit setup_local_APIC(void)
			printk("No ESR for 82489DX.\n");
			printk("No ESR for 82489DX.\n");
	}
	}


	if (nmi_watchdog == NMI_LOCAL_APIC)
	setup_apic_nmi_watchdog(NULL);
		setup_apic_nmi_watchdog();
	apic_pm_activate();
	apic_pm_activate();
}
}


+354 −183
Original line number Original line Diff line number Diff line
@@ -24,16 +24,10 @@


#include <asm/smp.h>
#include <asm/smp.h>
#include <asm/nmi.h>
#include <asm/nmi.h>
#include <asm/kdebug.h>


#include "mach_traps.h"
#include "mach_traps.h"


unsigned int nmi_watchdog = NMI_NONE;
extern int unknown_nmi_panic;
static unsigned int nmi_hz = HZ;
static unsigned int nmi_perfctr_msr;	/* the MSR to reset in NMI handler */
static unsigned int nmi_p4_cccr_val;
extern void show_registers(struct pt_regs *regs);

/* perfctr_nmi_owner tracks the ownership of the perfctr registers:
/* perfctr_nmi_owner tracks the ownership of the perfctr registers:
 * evtsel_nmi_owner tracks the ownership of the event selection
 * evtsel_nmi_owner tracks the ownership of the event selection
 * - different performance counters/ event selection may be reserved for
 * - different performance counters/ event selection may be reserved for
@@ -63,51 +57,31 @@ static unsigned int lapic_nmi_owner;
#define LAPIC_NMI_RESERVED	(1<<1)
#define LAPIC_NMI_RESERVED	(1<<1)


/* nmi_active:
/* nmi_active:
 * +1: the lapic NMI watchdog is active, but can be disabled
 * >0: the lapic NMI watchdog is active, but can be disabled
 *  0: the lapic NMI watchdog has not been set up, and cannot
 * <0: the lapic NMI watchdog has not been set up, and cannot
 *     be enabled
 *     be enabled
 * -1: the lapic NMI watchdog is disabled, but can be enabled
 *  0: the lapic NMI watchdog is disabled, but can be enabled
 */
 */
int nmi_active;
atomic_t nmi_active = ATOMIC_INIT(0);		/* oprofile uses this */


#define K7_EVNTSEL_ENABLE	(1 << 22)
unsigned int nmi_watchdog = NMI_DEFAULT;
#define K7_EVNTSEL_INT		(1 << 20)
static unsigned int nmi_hz = HZ;
#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


#define P6_EVNTSEL0_ENABLE	(1 << 22)
struct nmi_watchdog_ctlblk {
#define P6_EVNTSEL_INT		(1 << 20)
	int enabled;
#define P6_EVNTSEL_OS		(1 << 17)
	u64 check_bit;
#define P6_EVNTSEL_USR		(1 << 16)
	unsigned int cccr_msr;
#define P6_EVENT_CPU_CLOCKS_NOT_HALTED	0x79
	unsigned int perfctr_msr;  /* the MSR to reset in NMI handler */
#define P6_NMI_EVENT		P6_EVENT_CPU_CLOCKS_NOT_HALTED
	unsigned int evntsel_msr;  /* the MSR to select the events to handle */
};
static DEFINE_PER_CPU(struct nmi_watchdog_ctlblk, nmi_watchdog_ctlblk);


#define MSR_P4_MISC_ENABLE	0x1A0
/* local prototypes */
#define MSR_P4_MISC_ENABLE_PERF_AVAIL	(1<<7)
static void stop_apic_nmi_watchdog(void *unused);
#define MSR_P4_MISC_ENABLE_PEBS_UNAVAIL	(1<<12)
static int unknown_nmi_panic_callback(struct pt_regs *regs, int cpu);
#define MSR_P4_PERFCTR0		0x300

#define MSR_P4_CCCR0		0x360
extern void show_registers(struct pt_regs *regs);
#define P4_ESCR_EVENT_SELECT(N)	((N)<<25)
extern int unknown_nmi_panic;
#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)
/* 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] */
#define MSR_P4_IQ_COUNTER0	0x30C
#define P4_NMI_CRU_ESCR0	(P4_ESCR_EVENT_SELECT(0x3F)|P4_ESCR_OS|P4_ESCR_USR)
#define P4_NMI_IQ_CCCR0	\
	(P4_CCCR_OVF_PMI0|P4_CCCR_THRESHOLD(15)|P4_CCCR_COMPLEMENT|	\
	 P4_CCCR_COMPARE|P4_CCCR_REQUIRED|P4_CCCR_ESCR_SELECT(4)|P4_CCCR_ENABLE)


/* converts an msr to an appropriate reservation bit */
/* converts an msr to an appropriate reservation bit */
static inline unsigned int nmi_perfctr_msr_to_bit(unsigned int msr)
static inline unsigned int nmi_perfctr_msr_to_bit(unsigned int msr)
@@ -208,6 +182,17 @@ void release_evntsel_nmi(unsigned int msr)
	clear_bit(counter, &__get_cpu_var(evntsel_nmi_owner)[0]);
	clear_bit(counter, &__get_cpu_var(evntsel_nmi_owner)[0]);
}
}


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 == 6));
	case X86_VENDOR_INTEL:
		return ((boot_cpu_data.x86 == 15) || (boot_cpu_data.x86 == 6));
	}
	return 0;
}

#ifdef CONFIG_SMP
#ifdef CONFIG_SMP
/* The performance counters used by NMI_LOCAL_APIC don't trigger when
/* The performance counters used by NMI_LOCAL_APIC don't trigger when
 * the CPU is idle. To make sure the NMI watchdog really ticks on all
 * the CPU is idle. To make sure the NMI watchdog really ticks on all
@@ -234,7 +219,10 @@ static int __init check_nmi_watchdog(void)
	unsigned int *prev_nmi_count;
	unsigned int *prev_nmi_count;
	int cpu;
	int cpu;


	if (nmi_watchdog == NMI_NONE)
	if ((nmi_watchdog == NMI_NONE) || (nmi_watchdog == NMI_DEFAULT))
		return 0;

	if (!atomic_read(&nmi_active))
		return 0;
		return 0;


	prev_nmi_count = kmalloc(NR_CPUS * sizeof(int), GFP_KERNEL);
	prev_nmi_count = kmalloc(NR_CPUS * sizeof(int), GFP_KERNEL);
@@ -258,18 +246,22 @@ static int __init check_nmi_watchdog(void)
		if (!cpu_isset(cpu, cpu_callin_map))
		if (!cpu_isset(cpu, cpu_callin_map))
			continue;
			continue;
#endif
#endif
		if (!per_cpu(nmi_watchdog_ctlblk, cpu).enabled)
			continue;
		if (nmi_count(cpu) - prev_nmi_count[cpu] <= 5) {
		if (nmi_count(cpu) - prev_nmi_count[cpu] <= 5) {
			endflag = 1;
			printk("CPU#%d: NMI appears to be stuck (%d->%d)!\n",
			printk("CPU#%d: NMI appears to be stuck (%d->%d)!\n",
				cpu,
				cpu,
				prev_nmi_count[cpu],
				prev_nmi_count[cpu],
				nmi_count(cpu));
				nmi_count(cpu));
			nmi_active = 0;
			per_cpu(nmi_watchdog_ctlblk, cpu).enabled = 0;
			lapic_nmi_owner &= ~LAPIC_NMI_WATCHDOG;
			atomic_dec(&nmi_active);
		}
	}
	if (!atomic_read(&nmi_active)) {
		kfree(prev_nmi_count);
		kfree(prev_nmi_count);
		atomic_set(&nmi_active, -1);
		return -1;
		return -1;
	}
	}
	}
	endflag = 1;
	endflag = 1;
	printk("OK.\n");
	printk("OK.\n");


@@ -290,31 +282,16 @@ static int __init setup_nmi_watchdog(char *str)


	get_option(&str, &nmi);
	get_option(&str, &nmi);


	if (nmi >= NMI_INVALID)
	if ((nmi >= NMI_INVALID) || (nmi < NMI_NONE))
		return 0;
		return 0;
	if (nmi == NMI_NONE)
		nmi_watchdog = nmi;
	/*
	/*
	 * If any other x86 CPU has a local APIC, then
	 * If any other x86 CPU has a local APIC, then
	 * please test the NMI stuff there and send me the
	 * please test the NMI stuff there and send me the
	 * missing bits. Right now Intel P6/P4 and AMD K7 only.
	 * missing bits. Right now Intel P6/P4 and AMD K7 only.
	 */
	 */
	if ((nmi == NMI_LOCAL_APIC) &&
	if ((nmi == NMI_LOCAL_APIC) && (nmi_known_cpu() == 0))
			(boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) &&
		return 0;  /* no lapic support */
			(boot_cpu_data.x86 == 6 || boot_cpu_data.x86 == 15))
		nmi_watchdog = nmi;
	if ((nmi == NMI_LOCAL_APIC) &&
			(boot_cpu_data.x86_vendor == X86_VENDOR_AMD) &&
	  		(boot_cpu_data.x86 == 6 || boot_cpu_data.x86 == 15))
		nmi_watchdog = nmi;
	/*
	 * We can enable the IO-APIC watchdog
	 * unconditionally.
	 */
	if (nmi == NMI_IO_APIC) {
		nmi_active = 1;
	nmi_watchdog = nmi;
	nmi_watchdog = nmi;
	}
	return 1;
	return 1;
}
}


@@ -322,41 +299,30 @@ __setup("nmi_watchdog=", setup_nmi_watchdog);


static void disable_lapic_nmi_watchdog(void)
static void disable_lapic_nmi_watchdog(void)
{
{
	if (nmi_active <= 0)
	BUG_ON(nmi_watchdog != NMI_LOCAL_APIC);

	if (atomic_read(&nmi_active) <= 0)
		return;
		return;
	switch (boot_cpu_data.x86_vendor) {
	case X86_VENDOR_AMD:
		wrmsr(MSR_K7_EVNTSEL0, 0, 0);
		break;
	case X86_VENDOR_INTEL:
		switch (boot_cpu_data.x86) {
		case 6:
			if (boot_cpu_data.x86_model > 0xd)
				break;


			wrmsr(MSR_P6_EVNTSEL0, 0, 0);
	on_each_cpu(stop_apic_nmi_watchdog, NULL, 0, 1);
			break;
		case 15:
			if (boot_cpu_data.x86_model > 0x4)
				break;


			wrmsr(MSR_P4_IQ_CCCR0, 0, 0);
	BUG_ON(atomic_read(&nmi_active) != 0);
			wrmsr(MSR_P4_CRU_ESCR0, 0, 0);
			break;
		}
		break;
	}
	nmi_active = -1;
	/* tell do_nmi() and others that we're not active any more */
	nmi_watchdog = 0;
}
}


static void enable_lapic_nmi_watchdog(void)
static void enable_lapic_nmi_watchdog(void)
{
{
	if (nmi_active < 0) {
	BUG_ON(nmi_watchdog != NMI_LOCAL_APIC);
		nmi_watchdog = NMI_LOCAL_APIC;

		setup_apic_nmi_watchdog();
	/* 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();
}
}


int reserve_lapic_nmi(void)
int reserve_lapic_nmi(void)
@@ -388,20 +354,25 @@ void release_lapic_nmi(void)


void disable_timer_nmi_watchdog(void)
void disable_timer_nmi_watchdog(void)
{
{
	if ((nmi_watchdog != NMI_IO_APIC) || (nmi_active <= 0))
	BUG_ON(nmi_watchdog != NMI_IO_APIC);

	if (atomic_read(&nmi_active) <= 0)
		return;
		return;


	unset_nmi_callback();
	disable_irq(0);
	nmi_active = -1;
	on_each_cpu(stop_apic_nmi_watchdog, NULL, 0, 1);
	nmi_watchdog = NMI_NONE;

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


void enable_timer_nmi_watchdog(void)
void enable_timer_nmi_watchdog(void)
{
{
	if (nmi_active < 0) {
	BUG_ON(nmi_watchdog != NMI_IO_APIC);
		nmi_watchdog = NMI_IO_APIC;

	if (atomic_read(&nmi_active) == 0) {
		touch_nmi_watchdog();
		touch_nmi_watchdog();
		nmi_active = 1;
		on_each_cpu(setup_apic_nmi_watchdog, NULL, 0, 1);
		enable_irq(0);
	}
	}
}
}


@@ -411,7 +382,7 @@ static int nmi_pm_active; /* nmi_active before suspend */


static int lapic_nmi_suspend(struct sys_device *dev, pm_message_t state)
static int lapic_nmi_suspend(struct sys_device *dev, pm_message_t state)
{
{
	nmi_pm_active = nmi_active;
	nmi_pm_active = atomic_read(&nmi_active);
	disable_lapic_nmi_watchdog();
	disable_lapic_nmi_watchdog();
	return 0;
	return 0;
}
}
@@ -439,7 +410,13 @@ static int __init init_lapic_nmi_sysfs(void)
{
{
	int error;
	int error;


	if (nmi_active == 0 || nmi_watchdog != NMI_LOCAL_APIC)
	/* should really be a BUG_ON but b/c this is an
	 * init call, it just doesn't work.  -dcz
	 */
	if (nmi_watchdog != NMI_LOCAL_APIC)
		return 0;

	if ( atomic_read(&nmi_active) < 0 )
		return 0;
		return 0;


	error = sysdev_class_register(&nmi_sysclass);
	error = sysdev_class_register(&nmi_sysclass);
@@ -457,111 +434,245 @@ late_initcall(init_lapic_nmi_sysfs);
 * Original code written by Keith Owens.
 * Original code written by Keith Owens.
 */
 */


static void write_watchdog_counter(const char *descr)
static void write_watchdog_counter(unsigned int perfctr_msr, const char *descr)
{
{
	u64 count = (u64)cpu_khz * 1000;
	u64 count = (u64)cpu_khz * 1000;


	do_div(count, nmi_hz);
	do_div(count, nmi_hz);
	if(descr)
	if(descr)
		Dprintk("setting %s to -0x%08Lx\n", descr, count);
		Dprintk("setting %s to -0x%08Lx\n", descr, count);
	wrmsrl(nmi_perfctr_msr, 0 - count);
	wrmsrl(perfctr_msr, 0 - count);
}
}


/* 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)
static int setup_k7_watchdog(void)
{
{
	unsigned int perfctr_msr, evntsel_msr;
	unsigned int evntsel;
	unsigned int evntsel;
	struct nmi_watchdog_ctlblk *wd = &__get_cpu_var(nmi_watchdog_ctlblk);


	nmi_perfctr_msr = MSR_K7_PERFCTR0;
	perfctr_msr = MSR_K7_PERFCTR0;

	evntsel_msr = MSR_K7_EVNTSEL0;
	if (!reserve_perfctr_nmi(nmi_perfctr_msr))
	if (!reserve_perfctr_nmi(perfctr_msr))
		goto fail;
		goto fail;


	if (!reserve_evntsel_nmi(MSR_K7_EVNTSEL0))
	if (!reserve_evntsel_nmi(evntsel_msr))
		goto fail1;
		goto fail1;


	wrmsrl(MSR_K7_PERFCTR0, 0UL);
	wrmsrl(perfctr_msr, 0UL);


	evntsel = K7_EVNTSEL_INT
	evntsel = K7_EVNTSEL_INT
		| K7_EVNTSEL_OS
		| K7_EVNTSEL_OS
		| K7_EVNTSEL_USR
		| K7_EVNTSEL_USR
		| K7_NMI_EVENT;
		| K7_NMI_EVENT;


	wrmsr(MSR_K7_EVNTSEL0, evntsel, 0);
	/* setup the timer */
	write_watchdog_counter("K7_PERFCTR0");
	wrmsr(evntsel_msr, evntsel, 0);
	write_watchdog_counter(perfctr_msr, "K7_PERFCTR0");
	apic_write(APIC_LVTPC, APIC_DM_NMI);
	apic_write(APIC_LVTPC, APIC_DM_NMI);
	evntsel |= K7_EVNTSEL_ENABLE;
	evntsel |= K7_EVNTSEL_ENABLE;
	wrmsr(MSR_K7_EVNTSEL0, evntsel, 0);
	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;
	return 1;
fail1:
fail1:
	release_perfctr_nmi(nmi_perfctr_msr);
	release_perfctr_nmi(perfctr_msr);
fail:
fail:
	return 0;
	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(wd->evntsel_msr);
	release_perfctr_nmi(wd->perfctr_msr);
}

#define P6_EVNTSEL0_ENABLE	(1 << 22)
#define P6_EVNTSEL_INT		(1 << 20)
#define P6_EVNTSEL_OS		(1 << 17)
#define P6_EVNTSEL_USR		(1 << 16)
#define P6_EVENT_CPU_CLOCKS_NOT_HALTED	0x79
#define P6_NMI_EVENT		P6_EVENT_CPU_CLOCKS_NOT_HALTED

static int setup_p6_watchdog(void)
static int setup_p6_watchdog(void)
{
{
	unsigned int perfctr_msr, evntsel_msr;
	unsigned int evntsel;
	unsigned int evntsel;
	struct nmi_watchdog_ctlblk *wd = &__get_cpu_var(nmi_watchdog_ctlblk);


	nmi_perfctr_msr = MSR_P6_PERFCTR0;
	perfctr_msr = MSR_P6_PERFCTR0;

	evntsel_msr = MSR_P6_EVNTSEL0;
	if (!reserve_perfctr_nmi(nmi_perfctr_msr))
	if (!reserve_perfctr_nmi(perfctr_msr))
		goto fail;
		goto fail;


	if (!reserve_evntsel_nmi(MSR_P6_EVNTSEL0))
	if (!reserve_evntsel_nmi(evntsel_msr))
		goto fail1;
		goto fail1;


	wrmsrl(perfctr_msr, 0UL);

	evntsel = P6_EVNTSEL_INT
	evntsel = P6_EVNTSEL_INT
		| P6_EVNTSEL_OS
		| P6_EVNTSEL_OS
		| P6_EVNTSEL_USR
		| P6_EVNTSEL_USR
		| P6_NMI_EVENT;
		| P6_NMI_EVENT;


	wrmsr(MSR_P6_EVNTSEL0, evntsel, 0);
	/* setup the timer */
	write_watchdog_counter("P6_PERFCTR0");
	wrmsr(evntsel_msr, evntsel, 0);
	write_watchdog_counter(perfctr_msr, "P6_PERFCTR0");
	apic_write(APIC_LVTPC, APIC_DM_NMI);
	apic_write(APIC_LVTPC, APIC_DM_NMI);
	evntsel |= P6_EVNTSEL0_ENABLE;
	evntsel |= P6_EVNTSEL0_ENABLE;
	wrmsr(MSR_P6_EVNTSEL0, evntsel, 0);
	wrmsr(evntsel_msr, evntsel, 0);

	wd->perfctr_msr = perfctr_msr;
	wd->evntsel_msr = evntsel_msr;
	wd->cccr_msr = 0;  //unused
	wd->check_bit = 1ULL<<39;
	return 1;
	return 1;
fail1:
fail1:
	release_perfctr_nmi(nmi_perfctr_msr);
	release_perfctr_nmi(perfctr_msr);
fail:
fail:
	return 0;
	return 0;
}
}


static void stop_p6_watchdog(void)
{
	struct nmi_watchdog_ctlblk *wd = &__get_cpu_var(nmi_watchdog_ctlblk);

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

	release_evntsel_nmi(wd->evntsel_msr);
	release_perfctr_nmi(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)
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 misc_enable, dummy;
	unsigned int ht_num;
	struct nmi_watchdog_ctlblk *wd = &__get_cpu_var(nmi_watchdog_ctlblk);


	rdmsr(MSR_P4_MISC_ENABLE, misc_enable, dummy);
	rdmsr(MSR_IA32_MISC_ENABLE, misc_enable, dummy);
	if (!(misc_enable & MSR_P4_MISC_ENABLE_PERF_AVAIL))
	if (!(misc_enable & MSR_P4_MISC_ENABLE_PERF_AVAIL))
		return 0;
		return 0;


	nmi_perfctr_msr = MSR_P4_IQ_COUNTER0;
	nmi_p4_cccr_val = P4_NMI_IQ_CCCR0;
#ifdef CONFIG_SMP
#ifdef CONFIG_SMP
	if (smp_num_siblings == 2)
	/* detect which hyperthread we are on */
		nmi_p4_cccr_val |= P4_CCCR_OVF_PMI1;
	if (smp_num_siblings == 2) {
		unsigned int ebx, apicid;

        	ebx = cpuid_ebx(1);
	        apicid = (ebx >> 24) & 0xff;
        	ht_num = apicid & 1;
	} else
#endif
#endif
		ht_num = 0;


	if (!reserve_perfctr_nmi(nmi_perfctr_msr))
	/* 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(perfctr_msr))
		goto fail;
		goto fail;


	if (!reserve_evntsel_nmi(MSR_P4_CRU_ESCR0))
	if (!reserve_evntsel_nmi(evntsel_msr))
		goto fail1;
		goto fail1;


	wrmsr(MSR_P4_CRU_ESCR0, P4_NMI_CRU_ESCR0, 0);
	evntsel = P4_ESCR_EVENT_SELECT(0x3F)
	wrmsr(MSR_P4_IQ_CCCR0, P4_NMI_IQ_CCCR0 & ~P4_CCCR_ENABLE, 0);
	 	| P4_ESCR_OS
	write_watchdog_counter("P4_IQ_COUNTER0");
		| 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);
	write_watchdog_counter(perfctr_msr, "P4_IQ_COUNTER0");
	apic_write(APIC_LVTPC, APIC_DM_NMI);
	apic_write(APIC_LVTPC, APIC_DM_NMI);
	wrmsr(MSR_P4_IQ_CCCR0, nmi_p4_cccr_val, 0);
	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;
	return 1;
fail1:
fail1:
	release_perfctr_nmi(nmi_perfctr_msr);
	release_perfctr_nmi(perfctr_msr);
fail:
fail:
	return 0;
	return 0;
}
}


void setup_apic_nmi_watchdog (void)
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(wd->evntsel_msr);
	release_perfctr_nmi(wd->perfctr_msr);
}

void setup_apic_nmi_watchdog (void *unused)
{
{
	/* only support LOCAL and IO APICs for now */
	if ((nmi_watchdog != NMI_LOCAL_APIC) &&
	    (nmi_watchdog != NMI_IO_APIC))
	    	return;

	if (nmi_watchdog == NMI_LOCAL_APIC) {
		switch (boot_cpu_data.x86_vendor) {
		switch (boot_cpu_data.x86_vendor) {
		case X86_VENDOR_AMD:
		case X86_VENDOR_AMD:
			if (boot_cpu_data.x86 != 6 && boot_cpu_data.x86 != 15)
			if (boot_cpu_data.x86 != 6 && boot_cpu_data.x86 != 15)
@@ -592,8 +703,43 @@ void setup_apic_nmi_watchdog (void)
		default:
		default:
			return;
			return;
		}
		}
	lapic_nmi_owner = LAPIC_NMI_WATCHDOG;
	}
	nmi_active = 1;
	__get_cpu_var(nmi_watchdog_ctlblk.enabled) = 1;
	atomic_inc(&nmi_active);
}

static void stop_apic_nmi_watchdog(void *unused)
{
	/* only support LOCAL and IO APICs for now */
	if ((nmi_watchdog != NMI_LOCAL_APIC) &&
	    (nmi_watchdog != NMI_IO_APIC))
	    	return;

	if (nmi_watchdog == NMI_LOCAL_APIC) {
		switch (boot_cpu_data.x86_vendor) {
		case X86_VENDOR_AMD:
			stop_k7_watchdog();
			break;
		case X86_VENDOR_INTEL:
			switch (boot_cpu_data.x86) {
			case 6:
				if (boot_cpu_data.x86_model > 0xd)
					break;
				stop_p6_watchdog();
				break;
			case 15:
				if (boot_cpu_data.x86_model > 0x4)
					break;
				stop_p4_watchdog();
				break;
			}
			break;
		default:
			return;
		}
	}
	__get_cpu_var(nmi_watchdog_ctlblk.enabled) = 0;
	atomic_dec(&nmi_active);
}
}


/*
/*
@@ -635,7 +781,7 @@ EXPORT_SYMBOL(touch_nmi_watchdog);


extern void die_nmi(struct pt_regs *, const char *msg);
extern void die_nmi(struct pt_regs *, const char *msg);


void nmi_watchdog_tick (struct pt_regs * regs)
void nmi_watchdog_tick (struct pt_regs * regs, unsigned reason)
{
{


	/*
	/*
@@ -644,11 +790,21 @@ void nmi_watchdog_tick (struct pt_regs * regs)
	 * smp_processor_id().
	 * smp_processor_id().
	 */
	 */
	unsigned int sum;
	unsigned int sum;
	int touched = 0;
	int cpu = smp_processor_id();
	int cpu = smp_processor_id();
	struct nmi_watchdog_ctlblk *wd = &__get_cpu_var(nmi_watchdog_ctlblk);
	u64 dummy;

	/* check for other users first */
	if (notify_die(DIE_NMI, "nmi", regs, reason, 2, SIGINT)
			== NOTIFY_STOP) {
		touched = 1;
	}


	sum = per_cpu(irq_stat, cpu).apic_timer_irqs;
	sum = per_cpu(irq_stat, cpu).apic_timer_irqs;


	if (last_irq_sums[cpu] == sum) {
	/* if the apic timer isn't firing, this cpu isn't doing much */
	if (!touched && last_irq_sums[cpu] == sum) {
		/*
		/*
		 * Ayiee, looks like this CPU is stuck ...
		 * Ayiee, looks like this CPU is stuck ...
		 * wait a few IRQs (5 seconds) before doing the oops ...
		 * wait a few IRQs (5 seconds) before doing the oops ...
@@ -663,8 +819,17 @@ void nmi_watchdog_tick (struct pt_regs * regs)
		last_irq_sums[cpu] = sum;
		last_irq_sums[cpu] = sum;
		alert_counter[cpu] = 0;
		alert_counter[cpu] = 0;
	}
	}
	if (nmi_perfctr_msr) {
	/* see if the nmi watchdog went off */
		if (nmi_perfctr_msr == MSR_P4_IQ_COUNTER0) {
	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 P4 uses the cccr msr */
	 		if (wd->cccr_msr != 0) {
	 			/*
	 			/*
	 			 * P4 quirks:
	 			 * P4 quirks:
	 			 * - An overflown perfctr will assert its interrupt
	 			 * - An overflown perfctr will assert its interrupt
@@ -672,18 +837,24 @@ void nmi_watchdog_tick (struct pt_regs * regs)
	 			 * - LVTPC is masked on interrupt and must be
	 			 * - LVTPC is masked on interrupt and must be
	 			 *   unmasked by the LVTPC handler.
	 			 *   unmasked by the LVTPC handler.
	 			 */
	 			 */
			wrmsr(MSR_P4_IQ_CCCR0, nmi_p4_cccr_val, 0);
				rdmsrl(wd->cccr_msr, dummy);
				dummy &= ~P4_CCCR_OVF;
	 			wrmsrl(wd->cccr_msr, dummy);
	 			apic_write(APIC_LVTPC, APIC_DM_NMI);
	 			apic_write(APIC_LVTPC, APIC_DM_NMI);
	 		}
	 		}
		else if (nmi_perfctr_msr == MSR_P6_PERFCTR0) {
			else if (wd->perfctr_msr == MSR_P6_PERFCTR0) {
				/* Only P6 based Pentium M need to re-unmask
				/* Only P6 based Pentium M need to re-unmask
				 * the apic vector but it doesn't hurt
				 * the apic vector but it doesn't hurt
				 * other P6 variant */
				 * other P6 variant */
				apic_write(APIC_LVTPC, APIC_DM_NMI);
				apic_write(APIC_LVTPC, APIC_DM_NMI);
			}
			}
		write_watchdog_counter(NULL);
			/* start the cycle over again */
			write_watchdog_counter(wd->perfctr_msr, NULL);
		}
		}
	}
	}
done:
	return;
}


#ifdef CONFIG_SYSCTL
#ifdef CONFIG_SYSCTL


+1 −1
Original line number Original line Diff line number Diff line
@@ -724,7 +724,7 @@ static void default_do_nmi(struct pt_regs * regs)
		 * so it must be the NMI watchdog.
		 * so it must be the NMI watchdog.
		 */
		 */
		if (nmi_watchdog) {
		if (nmi_watchdog) {
			nmi_watchdog_tick(regs);
			nmi_watchdog_tick(regs, reason);
			return;
			return;
		}
		}
#endif
#endif
+1 −3
Original line number Original line Diff line number Diff line
@@ -42,9 +42,7 @@ static void timer_stop(void)


int __init op_nmi_timer_init(struct oprofile_operations * ops)
int __init op_nmi_timer_init(struct oprofile_operations * ops)
{
{
	extern int nmi_active;
	if (atomic_read(&nmi_active) <= 0)

	if (nmi_active <= 0)
		return -ENODEV;
		return -ENODEV;


	ops->start = timer_start;
	ops->start = timer_start;
+3 −2
Original line number Original line Diff line number Diff line
@@ -32,13 +32,14 @@ extern void release_perfctr_nmi(unsigned int);
extern int reserve_evntsel_nmi(unsigned int);
extern int reserve_evntsel_nmi(unsigned int);
extern void release_evntsel_nmi(unsigned int);
extern void release_evntsel_nmi(unsigned int);


extern void setup_apic_nmi_watchdog (void);
extern void setup_apic_nmi_watchdog (void *);
extern int reserve_lapic_nmi(void);
extern int reserve_lapic_nmi(void);
extern void release_lapic_nmi(void);
extern void release_lapic_nmi(void);
extern void disable_timer_nmi_watchdog(void);
extern void disable_timer_nmi_watchdog(void);
extern void enable_timer_nmi_watchdog(void);
extern void enable_timer_nmi_watchdog(void);
extern void nmi_watchdog_tick (struct pt_regs * regs);
extern void nmi_watchdog_tick (struct pt_regs * regs, unsigned reason);


extern atomic_t nmi_active;
extern unsigned int nmi_watchdog;
extern unsigned int nmi_watchdog;
#define NMI_DEFAULT     -1
#define NMI_DEFAULT     -1
#define NMI_NONE	0
#define NMI_NONE	0