kvm / dtrace: disable KVM steal-time accounting when DTrace is in use

This feature does clocksource work in interrupt context, which interoperates
badly with the DTrace probes there.

Signed-off-by: Nick Alcock <nick.alcock@oracle.com>

diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c
index 9435620062df30e549d1510baaf9c4c72ab90290..e2532a7c7475843cd0c301b8300ffbb57e643936 100644 (file)
--- a/arch/x86/kernel/kvm.c
+++ b/arch/x86/kernel/kvm.c
@@ -399,6 +399,7 @@ static struct notifier_block kvm_pv_reboot_nb = {
        .notifier_call = kvm_pv_reboot_notify,
 };
 
+#ifndef CONFIG_DTRACE
 static u64 kvm_steal_clock(int cpu)
 {
        u64 steal;
@@ -415,6 +416,7 @@ static u64 kvm_steal_clock(int cpu)
 
        return steal;
 }
+#endif
 
 void kvm_disable_steal_time(void)
 {
@@ -490,10 +492,12 @@ void __init kvm_guest_init(void)
        if (kvm_para_has_feature(KVM_FEATURE_ASYNC_PF))
                x86_init.irqs.trap_init = kvm_apf_trap_init;
 
+#ifndef CONFIG_DTRACE
        if (kvm_para_has_feature(KVM_FEATURE_STEAL_TIME)) {
                has_steal_clock = 1;
                pv_time_ops.steal_clock = kvm_steal_clock;
        }
+#endif
 
        if (kvm_para_has_feature(KVM_FEATURE_PV_EOI))
                apic_set_eoi_write(kvm_guest_apic_eoi_write);