From ca8723023f25c9a70d76cbd6101f8fb4ffec2fa0 Mon Sep 17 00:00:00 2001 From: Christian Borntraeger Date: Tue, 12 May 2009 17:21:49 +0200 Subject: KVM: s390: use hrtimer for clock wakeup from idle - v2 This patch reworks the s390 clock comparator wakeup to hrtimer. The clock comparator is a per-cpu value that is compared against the TOD clock. If ckc <= TOD an external interrupt 1004 is triggered. Since the clock comparator and the TOD clock have a much higher resolution than jiffies we should use hrtimers to trigger the wakeup. This speeds up guest nanosleep for small values. Since hrtimers callbacks run in hard-irq context, I added a tasklet to do the actual work with enabled interrupts. Signed-off-by: Christian Borntraeger Signed-off-by: Carsten Otte Signed-off-by: Christian Ehrhardt Signed-off-by: Avi Kivity --- arch/s390/kvm/kvm-s390.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) (limited to 'arch/s390/kvm/kvm-s390.c') diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c index 86567e174fd7..dc3d06811fd8 100644 --- a/arch/s390/kvm/kvm-s390.c +++ b/arch/s390/kvm/kvm-s390.c @@ -15,6 +15,7 @@ #include #include #include +#include #include #include #include @@ -283,8 +284,10 @@ int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu) vcpu->arch.sie_block->gmsor = vcpu->kvm->arch.guest_origin; vcpu->arch.sie_block->ecb = 2; vcpu->arch.sie_block->eca = 0xC1002001U; - setup_timer(&vcpu->arch.ckc_timer, kvm_s390_idle_wakeup, - (unsigned long) vcpu); + hrtimer_init(&vcpu->arch.ckc_timer, CLOCK_REALTIME, HRTIMER_MODE_ABS); + tasklet_init(&vcpu->arch.tasklet, kvm_s390_tasklet, + (unsigned long) vcpu); + vcpu->arch.ckc_timer.function = kvm_s390_idle_wakeup; get_cpu_id(&vcpu->arch.cpu_id); vcpu->arch.cpu_id.version = 0xff; return 0; -- cgit v1.2.2