path: root/arch/s390/kvm/kvm-s390.c
diff options
authorChristian Borntraeger <borntraeger@de.ibm.com>2009-05-12 17:21:49 +0200
committerAvi Kivity <avi@redhat.com>2009-06-10 11:48:55 +0300
commitca8723023f25c9a70d76cbd6101f8fb4ffec2fa0 (patch)
treeef753d244a55271279b5b2cf29b28db5b35b454c /arch/s390/kvm/kvm-s390.c
parent2668dab794272f0898491acaf1e77e9a005abc0f (diff)
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 <borntraeger@de.ibm.com> Signed-off-by: Carsten Otte <cotte@de.ibm.com> Signed-off-by: Christian Ehrhardt <ehrhardt@de.ibm.com> Signed-off-by: Avi Kivity <avi@redhat.com>
Diffstat (limited to 'arch/s390/kvm/kvm-s390.c')
1 files changed, 5 insertions, 2 deletions
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 86567e174fd..dc3d06811fd 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -15,6 +15,7 @@
#include <linux/compiler.h>
#include <linux/err.h>
#include <linux/fs.h>
+#include <linux/hrtimer.h>
#include <linux/init.h>
#include <linux/kvm.h>
#include <linux/kvm_host.h>
@@ -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;
vcpu->arch.cpu_id.version = 0xff;
return 0;