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>

diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h
index 3df1e97..c4072d9 100644 (file)
--- a/arch/arm/include/asm/kvm_host.h
+++ b/arch/arm/include/asm/kvm_host.h
@@ -33,6 +33,7 @@
 #define KVM_PRIVATE_MEM_SLOTS 4
 #define KVM_COALESCED_MMIO_PAGE_OFFSET 1
 #define KVM_HAVE_ONE_REG
+#define KVM_HALT_POLL_NS_DEFAULT 500000
 
 #define KVM_VCPU_MAX_FEATURES 2
 

diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index 4562459..ed03968 100644 (file)
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -33,6 +33,7 @@
 #define KVM_USER_MEM_SLOTS 32
 #define KVM_PRIVATE_MEM_SLOTS 4
 #define KVM_COALESCED_MMIO_PAGE_OFFSET 1
+#define KVM_HALT_POLL_NS_DEFAULT 500000
 
 #include <kvm/arm_vgic.h>
 #include <kvm/arm_arch_timer.h>

diff --git a/arch/mips/include/asm/kvm_host.h b/arch/mips/include/asm/kvm_host.h
index 3a54dbc..5a1a882 100644 (file)
--- a/arch/mips/include/asm/kvm_host.h
+++ b/arch/mips/include/asm/kvm_host.h
@@ -61,6 +61,7 @@
 #define KVM_PRIVATE_MEM_SLOTS  0
 
 #define KVM_COALESCED_MMIO_PAGE_OFFSET 1
+#define KVM_HALT_POLL_NS_DEFAULT 500000
 
 
 

diff --cc arch/powerpc/include/asm/kvm_host.h
Simple merge

diff --cc arch/s390/include/asm/kvm_host.h
Simple merge

diff --cc arch/x86/include/asm/kvm_host.h
Simple merge

diff --cc virt/kvm/kvm_main.c
Simple merge