# HG changeset patch
# User kaf24@xxxxxxxxxxxxxxxxxxxx
# Node ID 9d0120a5aa452049ae78488fb990c31a8b973fe8
# Parent 37ac3cf335066dfe0ab67809ac2809fede081cea
Clean up event-channel notification code in Xen.
Signed-off-by: Keir Fraser <keir@xxxxxxxxxxxxx>
diff -r 37ac3cf33506 -r 9d0120a5aa45 xen/arch/ia64/vcpu.c
--- a/xen/arch/ia64/vcpu.c Thu Aug 11 16:23:54 2005
+++ b/xen/arch/ia64/vcpu.c Thu Aug 11 16:48:36 2005
@@ -587,6 +587,14 @@
set_bit(vector,PSCBX(vcpu,irr));
PSCB(vcpu,pending_interruption) = 1;
}
+
+ /* Keir: I think you should unblock when an interrupt is pending. */
+ {
+ int running = test_bit(_VCPUF_running, &vcpu->vcpu_flags);
+ vcpu_unblock(vcpu);
+ if ( running )
+ smp_send_event_check_cpu(vcpu->processor);
+ }
}
void early_tick(VCPU *vcpu)
diff -r 37ac3cf33506 -r 9d0120a5aa45 xen/arch/x86/mm.c
--- a/xen/arch/x86/mm.c Thu Aug 11 16:23:54 2005
+++ b/xen/arch/x86/mm.c Thu Aug 11 16:48:36 2005
@@ -95,6 +95,7 @@
#include <xen/irq.h>
#include <xen/softirq.h>
#include <xen/domain_page.h>
+#include <xen/event.h>
#include <asm/shadow.h>
#include <asm/page.h>
#include <asm/flushtlb.h>
diff -r 37ac3cf33506 -r 9d0120a5aa45 xen/include/asm-x86/event.h
--- a/xen/include/asm-x86/event.h Thu Aug 11 16:23:54 2005
+++ b/xen/include/asm-x86/event.h Thu Aug 11 16:48:36 2005
@@ -11,6 +11,19 @@
static inline void evtchn_notify(struct vcpu *v)
{
+ /*
+ * NB1. 'vcpu_flags' and 'processor' must be checked /after/ update of
+ * pending flag. These values may fluctuate (after all, we hold no
+ * locks) but the key insight is that each change will cause
+ * evtchn_upcall_pending to be polled.
+ *
+ * NB2. We save VCPUF_running across the unblock to avoid a needless
+ * IPI for domains that we IPI'd to unblock.
+ */
+ int running = test_bit(_VCPUF_running, &v->vcpu_flags);
+ vcpu_unblock(v);
+ if ( running )
+ smp_send_event_check_cpu(v->processor);
}
#endif
diff -r 37ac3cf33506 -r 9d0120a5aa45 xen/include/xen/event.h
--- a/xen/include/xen/event.h Thu Aug 11 16:23:54 2005
+++ b/xen/include/xen/event.h Thu Aug 11 16:48:36 2005
@@ -26,30 +26,14 @@
{
struct domain *d = v->domain;
shared_info_t *s = d->shared_info;
- int running;
- /* These three operations must happen in strict order. */
+ /* These four operations must happen in strict order. */
if ( !test_and_set_bit(port, &s->evtchn_pending[0]) &&
!test_bit (port, &s->evtchn_mask[0]) &&
- !test_and_set_bit(port>>5, &v->vcpu_info->evtchn_pending_sel) )
+ !test_and_set_bit(port>>5, &v->vcpu_info->evtchn_pending_sel) &&
+ !test_and_set_bit(0, &v->vcpu_info->evtchn_upcall_pending) )
{
- /* The VCPU pending flag must be set /after/ update to evtchn-pend. */
- set_bit(0, &v->vcpu_info->evtchn_upcall_pending);
evtchn_notify(v);
-
- /*
- * NB1. 'vcpu_flags' and 'processor' must be checked /after/ update of
- * pending flag. These values may fluctuate (after all, we hold no
- * locks) but the key insight is that each change will cause
- * evtchn_upcall_pending to be polled.
- *
- * NB2. We save VCPUF_running across the unblock to avoid a needless
- * IPI for domains that we IPI'd to unblock.
- */
- running = test_bit(_VCPUF_running, &v->vcpu_flags);
- vcpu_unblock(v);
- if ( running )
- smp_send_event_check_cpu(v->processor);
}
}
@@ -73,8 +57,9 @@
*/
extern void send_guest_pirq(struct domain *d, int pirq);
-#define event_pending(_d) \
- ((_d)->vcpu_info->evtchn_upcall_pending && \
- !(_d)->vcpu_info->evtchn_upcall_mask)
+/* Note: Bitwise operations result in fast code with no branches. */
+#define event_pending(v) \
+ ((v)->vcpu_info->evtchn_upcall_pending & \
+ ~(v)->vcpu_info->evtchn_upcall_mask)
#endif /* __XEN_EVENT_H__ */
diff -r 37ac3cf33506 -r 9d0120a5aa45 xen/include/xen/sched.h
--- a/xen/include/xen/sched.h Thu Aug 11 16:23:54 2005
+++ b/xen/include/xen/sched.h Thu Aug 11 16:48:36 2005
@@ -297,10 +297,9 @@
(unsigned long)(_a1), (unsigned long)(_a2), (unsigned long)(_a3), \
(unsigned long)(_a4), (unsigned long)(_a5), (unsigned long)(_a6))
-#define hypercall_preempt_check() (unlikely( \
- softirq_pending(smp_processor_id()) | \
- (!!current->vcpu_info->evtchn_upcall_pending & \
- !current->vcpu_info->evtchn_upcall_mask) \
+#define hypercall_preempt_check() (unlikely( \
+ softirq_pending(smp_processor_id()) | \
+ event_pending(current) \
))
/* This domain_hash and domain_list are protected by the domlist_lock. */
_______________________________________________
Xen-changelog mailing list
Xen-changelog@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-changelog
|
Home