xen/vtimer: fixes and improvements

Do not try to save and restore the vtimer for the idle domain.

Inject the vtimer interrupt from the Xen timer handler, taking care of
setting the timer as masked in the ctl field, so that at restore time it
is not going to fire the interrupt again.

No need to disable the vtimer before writing the new offset on restore:
the vtimer is already disabled.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Committed-by: Ian Campbell <ian.campbell@citrix.com>

1 files changed, 8 insertions, 2 deletions

diff --git a/xen/arch/arm/vtimer.c b/xen/arch/arm/vtimer.c
index 85201b5b05..f4326f8ffd 100644
--- a/xen/arch/arm/vtimer.c
+++ b/xen/arch/arm/vtimer.c
@@ -40,7 +40,8 @@ static void phys_timer_expired(void *data)
 static void virt_timer_expired(void *data)
 {
     struct vtimer *t = data;
-    vcpu_wake(t->v);
+    t->ctl |= CNTx_CTL_MASK;
+    vgic_vcpu_inject_irq(t->v, 27, 1);
 }
  
 int vcpu_vtimer_init(struct vcpu *v)
@@ -73,6 +74,9 @@ void vcpu_timer_destroy(struct vcpu *v)
 
 int virt_timer_save(struct vcpu *v)
 {
+    if ( is_idle_domain(v->domain) )
+        return 0;
+
     v->arch.virt_timer.ctl = READ_CP32(CNTV_CTL);
     WRITE_CP32(v->arch.virt_timer.ctl & ~CNTx_CTL_ENABLE, CNTV_CTL);
     v->arch.virt_timer.cval = READ_CP64(CNTV_CVAL);
@@ -86,9 +90,11 @@ int virt_timer_save(struct vcpu *v)
 
 int virt_timer_restore(struct vcpu *v)
 {
+    if ( is_idle_domain(v->domain) )
+        return 0;
+
     stop_timer(&v->arch.virt_timer.timer);
 
-    WRITE_CP32(v->arch.virt_timer.ctl & ~CNTx_CTL_ENABLE, CNTV_CTL);
     WRITE_CP64(v->arch.virt_timer.offset, CNTVOFF);
     WRITE_CP64(v->arch.virt_timer.cval, CNTV_CVAL);
     WRITE_CP32(v->arch.virt_timer.ctl, CNTV_CTL);