commit 920552b213e3dc832a874b4e7ba29ecddbab31bc
author David Hildenbrand <dahi@linux.vnet.ibm.com> Fri Sep 18 12:34:53 2015 +0200
committer Paolo Bonzini <pbonzini@redhat.com> Fri Sep 25 10:31:30 2015 +0200
tree c07ed91961b7842a5056f98794c4827a0e493cea
parent 58c95070da3a504fbeca7939435bbb062cb96ea3

KVM: disable halt_poll_ns as default for s390x

We observed some performance degradation on s390x with dynamic
halt polling. Until we can provide a proper fix, let's enable
halt_poll_ns as default only for supported architectures.

Architectures are now free to set their own halt_poll_ns
default value.

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

arch/x86/include/asm/kvm_host.h

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 349f80a..2beee03 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -40,6 +40,7 @@
 
 #define KVM_PIO_PAGE_OFFSET 1
 #define KVM_COALESCED_MMIO_PAGE_OFFSET 2
+#define KVM_HALT_POLL_NS_DEFAULT 500000
 
 #define KVM_IRQCHIP_NUM_PINS  KVM_IOAPIC_NUM_PINS