[PATCH v2 3/8] evtchn: rename and adjust guest_enabled_event()

[Jan Beulich <jbeulich@xxxxxxxx>]

The function isn't about an "event" in general, but about a vIRQ. The
function also failed to honor global vIRQ-s, instead assuming the caller
would pass vCPU 0 in such a case.

While at it also adjust the
- types the function uses,
- single user to make use of domain_vcpu().

Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>
---
v2: New.

--- a/xen/arch/x86/cpu/mcheck/vmce.h
+++ b/xen/arch/x86/cpu/mcheck/vmce.h
@@ -5,9 +5,9 @@
 
 int vmce_init(struct cpuinfo_x86 *c);
 
-#define dom0_vmce_enabled() (hardware_domain && hardware_domain->max_vcpus \
-        && hardware_domain->vcpu[0] \
-        && guest_enabled_event(hardware_domain->vcpu[0], VIRQ_MCA))
+#define dom0_vmce_enabled() \
+    (hardware_domain && \
+     evtchn_virq_enabled(domain_vcpu(hardware_domain, 0), VIRQ_MCA))
 
 int unmmap_broken_page(struct domain *d, mfn_t mfn, unsigned long gfn);
 
--- a/xen/common/event_channel.c
+++ b/xen/common/event_channel.c
@@ -778,9 +778,15 @@ out:
     return ret;
 }
 
-int guest_enabled_event(struct vcpu *v, uint32_t virq)
+bool evtchn_virq_enabled(const struct vcpu *v, unsigned int virq)
 {
-    return ((v != NULL) && (v->virq_to_evtchn[virq] != 0));
+    if ( !v )
+        return false;
+
+    if ( virq_is_global(virq) && v->vcpu_id )
+        v = domain_vcpu(v->domain, 0);
+
+    return v->virq_to_evtchn[virq];
 }
 
 void send_guest_vcpu_virq(struct vcpu *v, uint32_t virq)
--- a/xen/include/xen/event.h
+++ b/xen/include/xen/event.h
@@ -85,8 +85,8 @@ int alloc_unbound_xen_event_channel(
     xen_event_channel_notification_t notification_fn);
 void free_xen_event_channel(struct domain *d, int port);
 
-/* Query if event channel is in use by the guest */
-int guest_enabled_event(struct vcpu *v, uint32_t virq);
+/* Query whether a vIRQ is in use by the guest. */
+bool evtchn_virq_enabled(const struct vcpu *v, unsigned int virq);
 
 /* Notify remote end of a Xen-attached event channel.*/
 void notify_via_xen_event_channel(struct domain *ld, int lport);