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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:  Don Zickus <dzickus@redhat.com>
Signed-off-by: Andi Kleen <ak@suse.de>
This commit is contained in:
Don Zickus 2006-09-26 10:52:26 +02:00 committed by Andi Kleen
parent f2802e7f57
commit b7471c6da9
5 changed files with 361 additions and 192 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
arch/i386/kernel/apic.c
View File

@ -586,8 +586,7 @@ void __devinit setup_local_APIC(void)
printk("No ESR for 82489DX.\n");
}
if (nmi_watchdog == NMI_LOCAL_APIC)
setup_apic_nmi_watchdog();
setup_apic_nmi_watchdog(NULL);
apic_pm_activate();
}

539
arch/i386/kernel/nmi.c
View File

@ -24,16 +24,10 @@
#include <asm/smp.h>
#include <asm/nmi.h>
#include <asm/kdebug.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:
* evtsel_nmi_owner tracks the ownership of the event selection
* - 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)
/* nmi_active:
* +1: 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 is active, but can be disabled
* <0: the lapic NMI watchdog has not been set up, and cannot
* 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)
#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
unsigned int nmi_watchdog = NMI_DEFAULT;
static unsigned int nmi_hz = HZ;
#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
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);
#define MSR_P4_MISC_ENABLE 0x1A0
#define MSR_P4_MISC_ENABLE_PERF_AVAIL (1<<7)
#define MSR_P4_MISC_ENABLE_PEBS_UNAVAIL (1<<12)
#define MSR_P4_PERFCTR0 0x300
#define MSR_P4_CCCR0 0x360
#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)
/* 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)
/* local prototypes */
static void stop_apic_nmi_watchdog(void *unused);
static int unknown_nmi_panic_callback(struct pt_regs *regs, int cpu);
extern void show_registers(struct pt_regs *regs);
extern int unknown_nmi_panic;
/* converts an msr to an appropriate reservation bit */
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]);
}
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
/* 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
@ -234,7 +219,10 @@ static int __init check_nmi_watchdog(void)
unsigned int *prev_nmi_count;
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;
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))
continue;
#endif
if (!per_cpu(nmi_watchdog_ctlblk, cpu).enabled)
continue;
if (nmi_count(cpu) - prev_nmi_count[cpu] <= 5) {
endflag = 1;
printk("CPU#%d: NMI appears to be stuck (%d->%d)!\n",
cpu,
prev_nmi_count[cpu],
nmi_count(cpu));
nmi_active = 0;
lapic_nmi_owner &= ~LAPIC_NMI_WATCHDOG;
kfree(prev_nmi_count);
return -1;
per_cpu(nmi_watchdog_ctlblk, cpu).enabled = 0;
atomic_dec(&nmi_active);
}
}
if (!atomic_read(&nmi_active)) {
kfree(prev_nmi_count);
atomic_set(&nmi_active, -1);
return -1;
}
endflag = 1;
printk("OK.\n");
@ -290,31 +282,16 @@ static int __init setup_nmi_watchdog(char *str)
get_option(&str, &nmi);
if (nmi >= NMI_INVALID)
if ((nmi >= NMI_INVALID) || (nmi < NMI_NONE))
return 0;
if (nmi == NMI_NONE)
nmi_watchdog = nmi;
/*
* If any other x86 CPU has a local APIC, then
* please test the NMI stuff there and send me the
* missing bits. Right now Intel P6/P4 and AMD K7 only.
*/
if ((nmi == NMI_LOCAL_APIC) &&
(boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) &&
(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;
}
if ((nmi == NMI_LOCAL_APIC) && (nmi_known_cpu() == 0))
return 0; /* no lapic support */
nmi_watchdog = nmi;
return 1;
}
@ -322,41 +299,30 @@ __setup("nmi_watchdog=", setup_nmi_watchdog);
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;
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);
break;
case 15:
if (boot_cpu_data.x86_model > 0x4)
break;
on_each_cpu(stop_apic_nmi_watchdog, NULL, 0, 1);
wrmsr(MSR_P4_IQ_CCCR0, 0, 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;
BUG_ON(atomic_read(&nmi_active) != 0);
}
static void enable_lapic_nmi_watchdog(void)
{
if (nmi_active < 0) {
nmi_watchdog = NMI_LOCAL_APIC;
setup_apic_nmi_watchdog();
}
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();
}
int reserve_lapic_nmi(void)
@ -388,20 +354,25 @@ void release_lapic_nmi(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;
unset_nmi_callback();
nmi_active = -1;
nmi_watchdog = NMI_NONE;
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)
{
if (nmi_active < 0) {
nmi_watchdog = NMI_IO_APIC;
BUG_ON(nmi_watchdog != NMI_IO_APIC);
if (atomic_read(&nmi_active) == 0) {
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)
{
nmi_pm_active = nmi_active;
nmi_pm_active = atomic_read(&nmi_active);
disable_lapic_nmi_watchdog();
return 0;
}
@ -439,7 +410,13 @@ static int __init init_lapic_nmi_sysfs(void)
{
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;
error = sysdev_class_register(&nmi_sysclass);
@ -457,143 +434,312 @@ late_initcall(init_lapic_nmi_sysfs);
* 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;
do_div(count, nmi_hz);
if(descr)
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)
{
unsigned int perfctr_msr, evntsel_msr;
unsigned int evntsel;
struct nmi_watchdog_ctlblk *wd = &__get_cpu_var(nmi_watchdog_ctlblk);
nmi_perfctr_msr = MSR_K7_PERFCTR0;
if (!reserve_perfctr_nmi(nmi_perfctr_msr))
perfctr_msr = MSR_K7_PERFCTR0;
evntsel_msr = MSR_K7_EVNTSEL0;
if (!reserve_perfctr_nmi(perfctr_msr))
goto fail;
if (!reserve_evntsel_nmi(MSR_K7_EVNTSEL0))
if (!reserve_evntsel_nmi(evntsel_msr))
goto fail1;
wrmsrl(MSR_K7_PERFCTR0, 0UL);
wrmsrl(perfctr_msr, 0UL);
evntsel = K7_EVNTSEL_INT
| K7_EVNTSEL_OS
| K7_EVNTSEL_USR
| K7_NMI_EVENT;
wrmsr(MSR_K7_EVNTSEL0, evntsel, 0);
write_watchdog_counter("K7_PERFCTR0");
/* setup the timer */
wrmsr(evntsel_msr, evntsel, 0);
write_watchdog_counter(perfctr_msr, "K7_PERFCTR0");
apic_write(APIC_LVTPC, APIC_DM_NMI);
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;
fail1:
release_perfctr_nmi(nmi_perfctr_msr);
release_perfctr_nmi(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(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)
{
unsigned int perfctr_msr, evntsel_msr;
unsigned int evntsel;
struct nmi_watchdog_ctlblk *wd = &__get_cpu_var(nmi_watchdog_ctlblk);
nmi_perfctr_msr = MSR_P6_PERFCTR0;
if (!reserve_perfctr_nmi(nmi_perfctr_msr))
perfctr_msr = MSR_P6_PERFCTR0;
evntsel_msr = MSR_P6_EVNTSEL0;
if (!reserve_perfctr_nmi(perfctr_msr))
goto fail;
if (!reserve_evntsel_nmi(MSR_P6_EVNTSEL0))
if (!reserve_evntsel_nmi(evntsel_msr))
goto fail1;
wrmsrl(perfctr_msr, 0UL);
evntsel = P6_EVNTSEL_INT
| P6_EVNTSEL_OS
| P6_EVNTSEL_USR
| P6_NMI_EVENT;
wrmsr(MSR_P6_EVNTSEL0, evntsel, 0);
write_watchdog_counter("P6_PERFCTR0");
/* setup the timer */
wrmsr(evntsel_msr, evntsel, 0);
write_watchdog_counter(perfctr_msr, "P6_PERFCTR0");
apic_write(APIC_LVTPC, APIC_DM_NMI);
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;
fail1:
release_perfctr_nmi(nmi_perfctr_msr);
release_perfctr_nmi(perfctr_msr);
fail:
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)
{
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_P4_MISC_ENABLE, misc_enable, dummy);
rdmsr(MSR_IA32_MISC_ENABLE, misc_enable, dummy);
if (!(misc_enable & MSR_P4_MISC_ENABLE_PERF_AVAIL))
return 0;
nmi_perfctr_msr = MSR_P4_IQ_COUNTER0;
nmi_p4_cccr_val = P4_NMI_IQ_CCCR0;
#ifdef CONFIG_SMP
if (smp_num_siblings == 2)
nmi_p4_cccr_val |= P4_CCCR_OVF_PMI1;
#endif
/* detect which hyperthread we are on */
if (smp_num_siblings == 2) {
unsigned int ebx, apicid;
if (!reserve_perfctr_nmi(nmi_perfctr_msr))
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(perfctr_msr))
goto fail;
if (!reserve_evntsel_nmi(MSR_P4_CRU_ESCR0))
if (!reserve_evntsel_nmi(evntsel_msr))
goto fail1;
wrmsr(MSR_P4_CRU_ESCR0, P4_NMI_CRU_ESCR0, 0);
wrmsr(MSR_P4_IQ_CCCR0, P4_NMI_IQ_CCCR0 & ~P4_CCCR_ENABLE, 0);
write_watchdog_counter("P4_IQ_COUNTER0");
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);
write_watchdog_counter(perfctr_msr, "P4_IQ_COUNTER0");
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;
fail1:
release_perfctr_nmi(nmi_perfctr_msr);
release_perfctr_nmi(perfctr_msr);
fail:
return 0;
}
void setup_apic_nmi_watchdog (void)
static void stop_p4_watchdog(void)
{
switch (boot_cpu_data.x86_vendor) {
case X86_VENDOR_AMD:
if (boot_cpu_data.x86 != 6 && boot_cpu_data.x86 != 15)
return;
if (!setup_k7_watchdog())
return;
break;
case X86_VENDOR_INTEL:
switch (boot_cpu_data.x86) {
case 6:
if (boot_cpu_data.x86_model > 0xd)
return;
struct nmi_watchdog_ctlblk *wd = &__get_cpu_var(nmi_watchdog_ctlblk);
if(!setup_p6_watchdog())
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) {
case X86_VENDOR_AMD:
if (boot_cpu_data.x86 != 6 && boot_cpu_data.x86 != 15)
return;
if (!setup_k7_watchdog())
return;
break;
case 15:
if (boot_cpu_data.x86_model > 0x4)
return;
case X86_VENDOR_INTEL:
switch (boot_cpu_data.x86) {
case 6:
if (boot_cpu_data.x86_model > 0xd)
return;
if (!setup_p4_watchdog())
if (!setup_p6_watchdog())
return;
break;
case 15:
if (boot_cpu_data.x86_model > 0x4)
return;
if (!setup_p4_watchdog())
return;
break;
default:
return;
}
break;
default:
return;
}
break;
default:
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);
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().
*/
unsigned int sum;
int touched = 0;
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;
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 ...
* wait a few IRQs (5 seconds) before doing the oops ...
@ -663,26 +819,41 @@ void nmi_watchdog_tick (struct pt_regs * regs)
last_irq_sums[cpu] = sum;
alert_counter[cpu] = 0;
}
if (nmi_perfctr_msr) {
if (nmi_perfctr_msr == MSR_P4_IQ_COUNTER0) {
/*
* 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.
*/
wrmsr(MSR_P4_IQ_CCCR0, nmi_p4_cccr_val, 0);
apic_write(APIC_LVTPC, APIC_DM_NMI);
/* 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 P4 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);
}
else if (wd->perfctr_msr == MSR_P6_PERFCTR0) {
/* Only P6 based Pentium M need to re-unmask
* the apic vector but it doesn't hurt
* other P6 variant */
apic_write(APIC_LVTPC, APIC_DM_NMI);
}
/* start the cycle over again */
write_watchdog_counter(wd->perfctr_msr, NULL);
}
else if (nmi_perfctr_msr == MSR_P6_PERFCTR0) {
/* Only P6 based Pentium M need to re-unmask
* the apic vector but it doesn't hurt
* other P6 variant */
apic_write(APIC_LVTPC, APIC_DM_NMI);
}
write_watchdog_counter(NULL);
}
done:
return;
}
#ifdef CONFIG_SYSCTL

2
arch/i386/kernel/traps.c
View File

@ -724,7 +724,7 @@ static void default_do_nmi(struct pt_regs * regs)
* so it must be the NMI watchdog.
*/
if (nmi_watchdog) {
nmi_watchdog_tick(regs);
nmi_watchdog_tick(regs, reason);
return;
}
#endif

4
arch/i386/oprofile/nmi_timer_int.c
View File

@ -42,9 +42,7 @@ static void timer_stop(void)
int __init op_nmi_timer_init(struct oprofile_operations * ops)
{
extern int nmi_active;
if (nmi_active <= 0)
if (atomic_read(&nmi_active) <= 0)
return -ENODEV;
ops->start = timer_start;

5
include/asm-i386/nmi.h
View File

@ -32,13 +32,14 @@ extern void release_perfctr_nmi(unsigned int);
extern int reserve_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 void release_lapic_nmi(void);
extern void disable_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;
#define NMI_DEFAULT -1
#define NMI_NONE 0