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Diffstat (limited to 'arch/x86/kernel/cpu/perfctr-watchdog.c')
-rw-r--r--arch/x86/kernel/cpu/perfctr-watchdog.c97
1 files changed, 81 insertions, 16 deletions
diff --git a/arch/x86/kernel/cpu/perfctr-watchdog.c b/arch/x86/kernel/cpu/perfctr-watchdog.c
index 05cc22dbd4f..9abd48b2267 100644
--- a/arch/x86/kernel/cpu/perfctr-watchdog.c
+++ b/arch/x86/kernel/cpu/perfctr-watchdog.c
@@ -17,6 +17,8 @@
#include <linux/bitops.h>
#include <linux/smp.h>
#include <linux/nmi.h>
+#include <linux/kprobes.h>
+
#include <asm/apic.h>
#include <asm/intel_arch_perfmon.h>
@@ -295,13 +297,19 @@ static int setup_k7_watchdog(unsigned nmi_hz)
/* setup the timer */
wrmsr(evntsel_msr, evntsel, 0);
write_watchdog_counter(perfctr_msr, "K7_PERFCTR0",nmi_hz);
- apic_write(APIC_LVTPC, APIC_DM_NMI);
- evntsel |= K7_EVNTSEL_ENABLE;
- wrmsr(evntsel_msr, evntsel, 0);
+ /* initialize the wd struct before enabling */
wd->perfctr_msr = perfctr_msr;
wd->evntsel_msr = evntsel_msr;
wd->cccr_msr = 0; /* unused */
+
+ /* ok, everything is initialized, announce that we're set */
+ cpu_nmi_set_wd_enabled();
+
+ apic_write(APIC_LVTPC, APIC_DM_NMI);
+ evntsel |= K7_EVNTSEL_ENABLE;
+ wrmsr(evntsel_msr, evntsel, 0);
+
return 1;
}
@@ -330,7 +338,8 @@ static void single_msr_unreserve(void)
release_perfctr_nmi(wd_ops->perfctr);
}
-static void single_msr_rearm(struct nmi_watchdog_ctlblk *wd, unsigned nmi_hz)
+static void __kprobes
+single_msr_rearm(struct nmi_watchdog_ctlblk *wd, unsigned nmi_hz)
{
/* start the cycle over again */
write_watchdog_counter(wd->perfctr_msr, NULL, nmi_hz);
@@ -379,17 +388,23 @@ static int setup_p6_watchdog(unsigned nmi_hz)
wrmsr(evntsel_msr, evntsel, 0);
nmi_hz = adjust_for_32bit_ctr(nmi_hz);
write_watchdog_counter32(perfctr_msr, "P6_PERFCTR0",nmi_hz);
- apic_write(APIC_LVTPC, APIC_DM_NMI);
- evntsel |= P6_EVNTSEL0_ENABLE;
- wrmsr(evntsel_msr, evntsel, 0);
+ /* initialize the wd struct before enabling */
wd->perfctr_msr = perfctr_msr;
wd->evntsel_msr = evntsel_msr;
wd->cccr_msr = 0; /* unused */
+
+ /* ok, everything is initialized, announce that we're set */
+ cpu_nmi_set_wd_enabled();
+
+ apic_write(APIC_LVTPC, APIC_DM_NMI);
+ evntsel |= P6_EVNTSEL0_ENABLE;
+ wrmsr(evntsel_msr, evntsel, 0);
+
return 1;
}
-static void p6_rearm(struct nmi_watchdog_ctlblk *wd, unsigned nmi_hz)
+static void __kprobes p6_rearm(struct nmi_watchdog_ctlblk *wd, unsigned nmi_hz)
{
/*
* P6 based Pentium M need to re-unmask
@@ -432,6 +447,27 @@ static const struct wd_ops p6_wd_ops = {
#define P4_CCCR_ENABLE (1 << 12)
#define P4_CCCR_OVF (1 << 31)
+#define P4_CONTROLS 18
+static unsigned int p4_controls[18] = {
+ MSR_P4_BPU_CCCR0,
+ MSR_P4_BPU_CCCR1,
+ MSR_P4_BPU_CCCR2,
+ MSR_P4_BPU_CCCR3,
+ MSR_P4_MS_CCCR0,
+ MSR_P4_MS_CCCR1,
+ MSR_P4_MS_CCCR2,
+ MSR_P4_MS_CCCR3,
+ MSR_P4_FLAME_CCCR0,
+ MSR_P4_FLAME_CCCR1,
+ MSR_P4_FLAME_CCCR2,
+ MSR_P4_FLAME_CCCR3,
+ MSR_P4_IQ_CCCR0,
+ MSR_P4_IQ_CCCR1,
+ MSR_P4_IQ_CCCR2,
+ MSR_P4_IQ_CCCR3,
+ MSR_P4_IQ_CCCR4,
+ MSR_P4_IQ_CCCR5,
+};
/*
* 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
@@ -473,6 +509,26 @@ static int setup_p4_watchdog(unsigned nmi_hz)
evntsel_msr = MSR_P4_CRU_ESCR0;
cccr_msr = MSR_P4_IQ_CCCR0;
cccr_val = P4_CCCR_OVF_PMI0 | P4_CCCR_ESCR_SELECT(4);
+
+ /*
+ * If we're on the kdump kernel or other situation, we may
+ * still have other performance counter registers set to
+ * interrupt and they'll keep interrupting forever because
+ * of the P4_CCCR_OVF quirk. So we need to ACK all the
+ * pending interrupts and disable all the registers here,
+ * before reenabling the NMI delivery. Refer to p4_rearm()
+ * about the P4_CCCR_OVF quirk.
+ */
+ if (reset_devices) {
+ unsigned int low, high;
+ int i;
+
+ for (i = 0; i < P4_CONTROLS; i++) {
+ rdmsr(p4_controls[i], low, high);
+ low &= ~(P4_CCCR_ENABLE | P4_CCCR_OVF);
+ wrmsr(p4_controls[i], low, high);
+ }
+ }
} else {
/* logical cpu 1 */
perfctr_msr = MSR_P4_IQ_PERFCTR1;
@@ -499,12 +555,17 @@ static int setup_p4_watchdog(unsigned nmi_hz)
wrmsr(evntsel_msr, evntsel, 0);
wrmsr(cccr_msr, cccr_val, 0);
write_watchdog_counter(perfctr_msr, "P4_IQ_COUNTER0", 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;
+
+ /* ok, everything is initialized, announce that we're set */
+ cpu_nmi_set_wd_enabled();
+
+ apic_write(APIC_LVTPC, APIC_DM_NMI);
+ cccr_val |= P4_CCCR_ENABLE;
+ wrmsr(cccr_msr, cccr_val, 0);
return 1;
}
@@ -547,7 +608,7 @@ static void p4_unreserve(void)
release_perfctr_nmi(MSR_P4_IQ_PERFCTR0);
}
-static void p4_rearm(struct nmi_watchdog_ctlblk *wd, unsigned nmi_hz)
+static void __kprobes p4_rearm(struct nmi_watchdog_ctlblk *wd, unsigned nmi_hz)
{
unsigned dummy;
/*
@@ -620,13 +681,17 @@ static int setup_intel_arch_watchdog(unsigned nmi_hz)
wrmsr(evntsel_msr, evntsel, 0);
nmi_hz = adjust_for_32bit_ctr(nmi_hz);
write_watchdog_counter32(perfctr_msr, "INTEL_ARCH_PERFCTR0", nmi_hz);
- 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 */
+
+ /* ok, everything is initialized, announce that we're set */
+ cpu_nmi_set_wd_enabled();
+
+ apic_write(APIC_LVTPC, APIC_DM_NMI);
+ evntsel |= ARCH_PERFMON_EVENTSEL0_ENABLE;
+ wrmsr(evntsel_msr, evntsel, 0);
intel_arch_wd_ops.checkbit = 1ULL << (eax.split.bit_width - 1);
return 1;
}
@@ -722,7 +787,7 @@ unsigned lapic_adjust_nmi_hz(unsigned hz)
return hz;
}
-int lapic_wd_event(unsigned nmi_hz)
+int __kprobes lapic_wd_event(unsigned nmi_hz)
{
struct nmi_watchdog_ctlblk *wd = &__get_cpu_var(nmi_watchdog_ctlblk);
u64 ctr;