Merge git://git.infradead.org/mtd-2.6
[sfrench/cifs-2.6.git] / arch / i386 / kernel / nmi.c
index 9f1e8c1afab75e26daa0ad1ebe6fec79a6a26aec..fba121f7973f7583c4e5de5f7eb77439f51fc4fe 100644 (file)
 #include <linux/sysdev.h>
 #include <linux/sysctl.h>
 #include <linux/percpu.h>
-#include <linux/dmi.h>
 #include <linux/kprobes.h>
 #include <linux/cpumask.h>
 #include <linux/kernel_stat.h>
+#include <linux/kdebug.h>
 
 #include <asm/smp.h>
 #include <asm/nmi.h>
-#include <asm/kdebug.h>
-#include <asm/intel_arch_perfmon.h>
 
 #include "mach_traps.h"
 
 int unknown_nmi_panic;
 int nmi_watchdog_enabled;
 
-/* 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 long, perfctr_nmi_owner[NMI_MAX_COUNTER_LONGS]);
-static DEFINE_PER_CPU(unsigned long, evntsel_nmi_owner[NMI_MAX_COUNTER_LONGS]);
-
 static cpumask_t backtrace_mask = CPU_MASK_NONE;
+
 /* nmi_active:
  * >0: the lapic NMI watchdog is active, but can be disabled
  * <0: the lapic NMI watchdog has not been set up, and cannot
@@ -63,206 +46,11 @@ atomic_t nmi_active = ATOMIC_INIT(0);              /* oprofile uses this */
 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);
 
-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)
-{
-       /* 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);
-
-               switch (boot_cpu_data.x86) {
-               case 6:
-                       return (msr - MSR_P6_PERFCTR0);
-               case 15:
-                       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);
-
-               switch (boot_cpu_data.x86) {
-               case 6:
-                       return (msr - MSR_P6_EVNTSEL0);
-               case 15:
-                       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 == 6)
-                       || (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) || (boot_cpu_data.x86 == 6));
-       }
-       return 0;
-}
-
 static int endflag __initdata = 0;
 
 #ifdef CONFIG_SMP
@@ -284,28 +72,6 @@ static __init void nmi_cpu_busy(void *data)
 }
 #endif
 
-static unsigned int adjust_for_32bit_ctr(unsigned int hz)
-{
-       u64 counter_val;
-       unsigned int retval = hz;
-
-       /*
-        * On Intel CPUs with P6/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
-        */
-       counter_val = (u64)cpu_khz * 1000;
-       do_div(counter_val, retval);
-       if (counter_val > 0x7fffffffULL) {
-               u64 count = (u64)cpu_khz * 1000;
-               do_div(count, 0x7fffffffUL);
-               retval = count + 1;
-       }
-       return retval;
-}
-
 static int __init check_nmi_watchdog(void)
 {
        unsigned int *prev_nmi_count;
@@ -338,14 +104,14 @@ static int __init check_nmi_watchdog(void)
                if (!cpu_isset(cpu, cpu_callin_map))
                        continue;
 #endif
-               if (!per_cpu(nmi_watchdog_ctlblk, cpu).enabled)
+               if (!per_cpu(wd_enabled, cpu))
                        continue;
                if (nmi_count(cpu) - prev_nmi_count[cpu] <= 5) {
                        printk("CPU#%d: NMI appears to be stuck (%d->%d)!\n",
                                cpu,
                                prev_nmi_count[cpu],
                                nmi_count(cpu));
-                       per_cpu(nmi_watchdog_ctlblk, cpu).enabled = 0;
+                       per_cpu(wd_enabled, cpu) = 0;
                        atomic_dec(&nmi_active);
                }
        }
@@ -359,16 +125,8 @@ static 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_P6_PERFCTR0 ||
-                   wd->perfctr_msr == MSR_ARCH_PERFMON_PERFCTR0) {
-                       nmi_hz = adjust_for_32bit_ctr(nmi_hz);
-               }
-       }
+       if (nmi_watchdog == NMI_LOCAL_APIC)
+               nmi_hz = lapic_adjust_nmi_hz(1);
 
        kfree(prev_nmi_count);
        return 0;
@@ -391,85 +149,8 @@ static 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)
-{
-       apic_write_around(APIC_LVT0, APIC_DM_NMI | APIC_LVT_MASKED);
-}
-
-/*
- * Disable timer based NMIs on all CPUs:
- */
-void acpi_nmi_disable(void)
-{
-       if (atomic_read(&nmi_active) && nmi_watchdog == NMI_IO_APIC)
-               on_each_cpu(__acpi_nmi_disable, NULL, 0, 1);
-}
-
-static void __acpi_nmi_enable(void *__unused)
-{
-       apic_write_around(APIC_LVT0, APIC_DM_NMI);
-}
-
-/*
- * Enable timer based NMIs on all CPUs:
- */
-void acpi_nmi_enable(void)
-{
-       if (atomic_read(&nmi_active) && nmi_watchdog == NMI_IO_APIC)
-               on_each_cpu(__acpi_nmi_enable, NULL, 0, 1);
-}
+/* Suspend/resume support */
 
 #ifdef CONFIG_PM
 
@@ -516,7 +197,7 @@ static int __init init_lapic_nmi_sysfs(void)
        if (nmi_watchdog != NMI_LOCAL_APIC)
                return 0;
 
-       if ( atomic_read(&nmi_active) < 0 )
+       if (atomic_read(&nmi_active) < 0)
                return 0;
 
        error = sysdev_class_register(&nmi_sysclass);
@@ -529,433 +210,69 @@ late_initcall(init_lapic_nmi_sysfs);
 
 #endif /* CONFIG_PM */
 
-/*
- * Activate the NMI watchdog via the local APIC.
- * Original code written by Keith Owens.
- */
-
-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(perfctr_msr, 0 - count);
-}
-
-static void write_watchdog_counter32(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);
-       wrmsr(perfctr_msr, (u32)(-count), 0);
-}
-
-/* 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;
-
-       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);
-       write_watchdog_counter(perfctr_msr, "K7_PERFCTR0");
-       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;
-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);
-}
-
-#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);
-
-       perfctr_msr = MSR_P6_PERFCTR0;
-       evntsel_msr = MSR_P6_EVNTSEL0;
-       if (!__reserve_perfctr_nmi(-1, perfctr_msr))
-               goto fail;
-
-       if (!__reserve_evntsel_nmi(-1, evntsel_msr))
-               goto fail1;
-
-       wrmsrl(perfctr_msr, 0UL);
-
-       evntsel = P6_EVNTSEL_INT
-               | P6_EVNTSEL_OS
-               | P6_EVNTSEL_USR
-               | P6_NMI_EVENT;
-
-       /* setup the timer */
-       wrmsr(evntsel_msr, evntsel, 0);
-       nmi_hz = adjust_for_32bit_ctr(nmi_hz);
-       write_watchdog_counter32(perfctr_msr, "P6_PERFCTR0");
-       apic_write(APIC_LVTPC, APIC_DM_NMI);
-       evntsel |= P6_EVNTSEL0_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<<39;
-       return 1;
-fail1:
-       __release_perfctr_nmi(-1, 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(-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)
+static void __acpi_nmi_enable(void *__unused)
 {
-       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);
-       write_watchdog_counter(perfctr_msr, "P4_IQ_COUNTER0");
-       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;
+       apic_write_around(APIC_LVT0, APIC_DM_NMI);
 }
 
-static void stop_p4_watchdog(void)
+/*
+ * Enable timer based NMIs on all CPUs:
+ */
+void acpi_nmi_enable(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);
+       if (atomic_read(&nmi_active) && nmi_watchdog == NMI_IO_APIC)
+               on_each_cpu(__acpi_nmi_enable, NULL, 0, 1);
 }
 
-#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)
+static void __acpi_nmi_disable(void *__unused)
 {
-       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_PERFCTR0;
-       evntsel_msr = MSR_ARCH_PERFMON_EVENTSEL0;
-
-       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);
-       write_watchdog_counter32(perfctr_msr, "INTEL_ARCH_PERFCTR0");
-       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;
+       apic_write(APIC_LVT0, APIC_DM_NMI | APIC_LVT_MASKED);
 }
 
-static void stop_intel_arch_watchdog(void)
+/*
+ * Disable timer based NMIs on all CPUs:
+ */
+void acpi_nmi_disable(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);
+       if (atomic_read(&nmi_active) && nmi_watchdog == NMI_IO_APIC)
+               on_each_cpu(__acpi_nmi_disable, NULL, 0, 1);
 }
 
 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)
-               return;
+       if (__get_cpu_var(wd_enabled))
+               return;
 
        /* cheap hack to support suspend/resume */
        /* if cpu0 is not active neither should the other cpus */
        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 (boot_cpu_data.x86 != 6 && boot_cpu_data.x86 != 15 &&
-                               boot_cpu_data.x86 != 16)
-                               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;
-                       }
-                       switch (boot_cpu_data.x86) {
-                       case 6:
-                               if (boot_cpu_data.x86_model > 0xd)
-                                       return;
-
-                               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:
+       switch (nmi_watchdog) {
+       case NMI_LOCAL_APIC:
+               __get_cpu_var(wd_enabled) = 1; /* enable it before to avoid race with handler */
+               if (lapic_watchdog_init(nmi_hz) < 0) {
+                       __get_cpu_var(wd_enabled) = 0;
                        return;
                }
+               /* FALL THROUGH */
+       case NMI_IO_APIC:
+               __get_cpu_var(wd_enabled) = 1;
+               atomic_inc(&nmi_active);
        }
-       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:
-                       stop_k7_watchdog();
-                       break;
-               case X86_VENDOR_INTEL:
-                       if (cpu_has(&boot_cpu_data, X86_FEATURE_ARCH_PERFMON)) {
-                               stop_intel_arch_watchdog();
-                               break;
-                       }
-                       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;
-               }
-       }
-       wd->enabled = 0;
+       if (nmi_watchdog == NMI_LOCAL_APIC)
+               lapic_watchdog_stop();
+       __get_cpu_var(wd_enabled) = 0;
        atomic_dec(&nmi_active);
 }
 
@@ -1011,8 +328,6 @@ __kprobes int nmi_watchdog_tick(struct pt_regs * regs, unsigned reason)
        unsigned 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 */
@@ -1055,53 +370,20 @@ __kprobes int nmi_watchdog_tick(struct pt_regs * regs, unsigned reason)
                alert_counter[cpu] = 0;
        }
        /* 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);
-                               /* start the cycle over again */
-                               write_watchdog_counter(wd->perfctr_msr, NULL);
-                       }
-                       else if (wd->perfctr_msr == MSR_P6_PERFCTR0 ||
-                                wd->perfctr_msr == MSR_ARCH_PERFMON_PERFCTR0) {
-                               /* P6 based Pentium M need to re-unmask
-                                * the apic vector but it doesn't hurt
-                                * other P6 variant.
-                                * ArchPerfom/Core Duo also needs this */
-                               apic_write(APIC_LVTPC, APIC_DM_NMI);
-                               /* P6/ARCH_PERFMON has 32 bit counter write */
-                               write_watchdog_counter32(wd->perfctr_msr, NULL);
-                       } else {
-                               /* start the cycle over again */
-                               write_watchdog_counter(wd->perfctr_msr, NULL);
-                       }
-                       rc = 1;
-               } else if (nmi_watchdog == 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;
-               }
+       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;
+               break;
        }
-done:
        return rc;
 }
 
@@ -1146,7 +428,7 @@ int proc_nmi_enabled(struct ctl_table *table, int write, struct file *file,
        }
 
        if (nmi_watchdog == NMI_DEFAULT) {
-               if (nmi_known_cpu() > 0)
+               if (lapic_watchdog_ok())
                        nmi_watchdog = NMI_LOCAL_APIC;
                else
                        nmi_watchdog = NMI_IO_APIC;
@@ -1182,11 +464,3 @@ 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);