trace: dynamically allocate event IDs at runtime

Instead of having the code generator assign event IDs and
event VCPU IDs, assign them when the events are registered
at runtime. This will allow code to be generated from
individual trace-events without having to figure out
globally unique numbering at build time.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Lluís Vilanova <vilanova@ac.upc.edu>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 1475588159-30598-16-git-send-email-berrange@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

2 files changed, 2 insertions, 12 deletions

diff --git a/scripts/tracetool/format/events_c.py b/scripts/tracetool/format/events_c.py
index 8817555..a976c22 100644
--- a/scripts/tracetool/format/events_c.py
+++ b/scripts/tracetool/format/events_c.py
@@ -28,25 +28,19 @@ def generate(events, backend):
     for e in events:
         out('uint16_t %s;' % e.api(e.QEMU_DSTATE))
 
-    next_id = 0
-    next_vcpu_id = 0
     for e in events:
-        id = next_id
-        next_id += 1
         if "vcpu" in e.properties:
-            vcpu_id = next_vcpu_id
-            next_vcpu_id += 1
+            vcpu_id = 0
         else:
             vcpu_id = "TRACE_VCPU_EVENT_NONE"
         out('TraceEvent %(event)s = {',
-            '    .id = %(id)s,',
+            '    .id = 0,',
             '    .vcpu_id = %(vcpu_id)s,',
             '    .name = \"%(name)s\",',
             '    .sstate = %(sstate)s,',
             '    .dstate = &%(dstate)s ',
             '};',
             event = e.api(e.QEMU_EVENT),
-            id = id,
             vcpu_id = vcpu_id,
             name = e.name,
             sstate = "TRACE_%s_ENABLED" % e.name.upper(),
diff --git a/scripts/tracetool/format/events_h.py b/scripts/tracetool/format/events_h.py
index ca6d730..1cb332b 100644
--- a/scripts/tracetool/format/events_h.py
+++ b/scripts/tracetool/format/events_h.py
@@ -32,10 +32,6 @@ def generate(events, backend):
     for e in events:
         out('extern uint16_t %s;' % e.api(e.QEMU_DSTATE))
 
-    numvcpu = len([e for e in events if "vcpu" in e.properties])
-
-    out("#define TRACE_VCPU_EVENT_COUNT %d" % numvcpu)
-
     # static state
     for e in events:
         if 'disable' in e.properties: