KVM will respond to setting MSR[WE], no matter what is in HID0.
With KVM we also know it will take effect right away, so no need for
a loop, TLF_NAPPING, etc.
KVM paravirt's initcall is moved before SMP init, to avoid any chance
of a race when updating the idle loop handler.
Signed-off-by: Scott Wood <scottwood@xxxxxxxxxxxxx>
---
arch/powerpc/kernel/kvm.c | 21 ++++++++++++++++++++-
1 files changed, 20 insertions(+), 1 deletions(-)
diff --git a/arch/powerpc/kernel/kvm.c b/arch/powerpc/kernel/kvm.c
index eb95a03..5e13500 100644
--- a/arch/powerpc/kernel/kvm.c
+++ b/arch/powerpc/kernel/kvm.c
@@ -30,6 +30,7 @@
#include <asm/cacheflush.h>
#include <asm/disassemble.h>
#include <asm/ppc-opcode.h>
+#include <asm/machdep.h>
#define KVM_MAGIC_PAGE (-4096L)
#define magic_var(x) KVM_MAGIC_PAGE + offsetof(struct kvm_vcpu_arch_shared, x)
@@ -774,6 +775,13 @@ static __init void kvm_free_tmp(void)
}
}
+#ifdef CONFIG_E500
+static void kvm_msrwe_idle(void)
+{
+ mtmsr(mfmsr() | MSR_WE | MSR_EE);
+}
+#endif
+
static int __init kvm_guest_init(void)
{
if (!kvm_para_available())
@@ -789,6 +797,17 @@ static int __init kvm_guest_init(void)
/* Enable napping */
powersave_nap = 1;
#endif
+#ifdef CONFIG_E500
+ /*
+ * Skip the overhead of HID0 accesses that KVM ignores --
+ * just write MSR[WE].
+ *
+ * We don't need _TLF_NAPPING, because under KVM we know
+ * it will take effect right away.
+ */
+ if (ppc_md.power_save == e500_idle)
+ ppc_md.power_save = kvm_msrwe_idle;
+#endif
free_tmp:
kvm_free_tmp();
@@ -796,4 +815,4 @@ free_tmp:
return 0;
}
-postcore_initcall(kvm_guest_init);
+early_initcall(kvm_guest_init);
--
1.7.6
--
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