trace: Add per-vCPU tracing states for events with the 'vcpu' property

Each vCPU gets a 'trace_dstate' bitmap to control the per-vCPU dynamic
tracing state of events with the 'vcpu' property.

Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

1 files changed, 23 insertions, 7 deletions

diff --git a/trace/control-internal.h b/trace/control-internal.h
index b326d88d72..a4e5f4aa06 100644
--- a/trace/control-internal.h
+++ b/trace/control-internal.h
@@ -10,8 +10,13 @@
 #ifndef TRACE__CONTROL_INTERNAL_H
 #define TRACE__CONTROL_INTERNAL_H
 
+#include <stddef.h>                     /* size_t */
+
+#include "qom/cpu.h"
+
+
 extern TraceEvent trace_events[];
-extern bool trace_events_dstate[];
+extern uint16_t trace_events_dstate[];
 extern int trace_events_enabled_count;
 
 
@@ -74,13 +79,24 @@ static inline bool trace_event_get_state_dynamic(TraceEvent *ev)
     return trace_event_get_state_dynamic_by_id(id);
 }
 
-static inline void trace_event_set_state_dynamic(TraceEvent *ev, bool state)
+static inline bool trace_event_get_vcpu_state_dynamic_by_vcpu_id(CPUState *vcpu,
+                                                                 TraceEventVCPUID id)
 {
-    int id = trace_event_get_id(ev);
-    assert(ev != NULL);
-    assert(trace_event_get_state_static(ev));
-    trace_events_enabled_count += state - trace_events_dstate[id];
-    trace_events_dstate[id] = state;
+    /* it's on fast path, avoid consistency checks (asserts) */
+    if (unlikely(trace_events_enabled_count)) {
+        return test_bit(id, vcpu->trace_dstate);
+    } else {
+        return false;
+    }
+}
+
+static inline bool trace_event_get_vcpu_state_dynamic(CPUState *vcpu,
+                                                      TraceEvent *ev)
+{
+    TraceEventVCPUID id;
+    assert(trace_event_is_vcpu(ev));
+    id = trace_event_get_vcpu_id(ev);
+    return trace_event_get_vcpu_state_dynamic_by_vcpu_id(vcpu, id);
 }
 
 #endif /* TRACE__CONTROL_INTERNAL_H */