KVM: Add kvm_arch_vcpu_{un}blocking callbacks

Some times it is useful for architecture implementations of KVM to know
when the VCPU thread is about to block or when it comes back from
blocking (arm/arm64 needs to know this to properly implement timers, for
example).

Therefore provide a generic architecture callback function in line with
what we do elsewhere for KVM generic-arch interactions.

Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>

1 files changed, 3 insertions, 0 deletions

diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 8db1d9361993..7873d6daccb1 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -2018,6 +2018,8 @@ void kvm_vcpu_block(struct kvm_vcpu *vcpu)
                 } while (single_task_running() && ktime_before(cur, stop));
         }
 
+        kvm_arch_vcpu_blocking(vcpu);
+
         for (;;) {
                 prepare_to_wait(&vcpu->wq, &wait, TASK_INTERRUPTIBLE);
 
@@ -2031,6 +2033,7 @@ void kvm_vcpu_block(struct kvm_vcpu *vcpu)
         finish_wait(&vcpu->wq, &wait);
         cur = ktime_get();
 
+        kvm_arch_vcpu_unblocking(vcpu);
 out:
         block_ns = ktime_to_ns(cur) - ktime_to_ns(start);