Avi, Marcello,

Newer (guest) kernels use sigp sense running in their spinlock
implementation to check if the other cpu is running before yielding
the processor. This revealed some wrong guest settings, causing
unnecessary exits for every sigp sense running.
 
Signed-off-by: Christian Borntraeger <[email protected]>

---
 arch/s390/include/asm/kvm_host.h |    2 +-
 arch/s390/kvm/kvm-s390.c         |    4 +++-
 2 files changed, 4 insertions(+), 2 deletions(-)

Index: kvm/arch/s390/include/asm/kvm_host.h
===================================================================
--- kvm.orig/arch/s390/include/asm/kvm_host.h
+++ kvm/arch/s390/include/asm/kvm_host.h
@@ -26,7 +26,7 @@
 
 struct sca_entry {
        atomic_t scn;
-       __u64   reserved;
+       __u32   reserved;
        __u64   sda;
        __u64   reserved2[2];
 } __attribute__((packed));
Index: kvm/arch/s390/kvm/kvm-s390.c
===================================================================
--- kvm.orig/arch/s390/kvm/kvm-s390.c
+++ kvm/arch/s390/kvm/kvm-s390.c
@@ -207,6 +207,7 @@ out_nokvm:
 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
 {
        VCPU_EVENT(vcpu, 3, "%s", "free cpu");
+       clear_bit(63 - vcpu->vcpu_id, (unsigned long *) 
&vcpu->kvm->arch.sca->mcn);
        if (vcpu->kvm->arch.sca->cpu[vcpu->vcpu_id].sda ==
                (__u64) vcpu->arch.sie_block)
                vcpu->kvm->arch.sca->cpu[vcpu->vcpu_id].sda = 0;
@@ -296,7 +297,7 @@ int kvm_arch_vcpu_setup(struct kvm_vcpu 
 {
        atomic_set(&vcpu->arch.sie_block->cpuflags, CPUSTAT_ZARCH);
        set_bit(KVM_REQ_MMU_RELOAD, &vcpu->requests);
-       vcpu->arch.sie_block->ecb   = 2;
+       vcpu->arch.sie_block->ecb   = 6;
        vcpu->arch.sie_block->eca   = 0xC1002001U;
        vcpu->arch.sie_block->fac   = (int) (long) facilities;
        hrtimer_init(&vcpu->arch.ckc_timer, CLOCK_REALTIME, HRTIMER_MODE_ABS);
@@ -329,6 +330,7 @@ struct kvm_vcpu *kvm_arch_vcpu_create(st
                kvm->arch.sca->cpu[id].sda = (__u64) vcpu->arch.sie_block;
        vcpu->arch.sie_block->scaoh = (__u32)(((__u64)kvm->arch.sca) >> 32);
        vcpu->arch.sie_block->scaol = (__u32)(__u64)kvm->arch.sca;
+       set_bit(63 - id, (unsigned long *) &kvm->arch.sca->mcn);
 
        spin_lock_init(&vcpu->arch.local_int.lock);
        INIT_LIST_HEAD(&vcpu->arch.local_int.list);
--
To unsubscribe from this list: send the line "unsubscribe kvm" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to