[Qemu-devel] [PATCH] simpletrace: fix timestamp argument type

[Stefan Hajnoczi <stefanha@redhat.com>]

The timestamp argument to a trace event method is documented as follows:

  The method can also take a timestamp argument before the trace event
  arguments:

    def runstate_set(self, timestamp, new_state):
        ...

  Timestamps have the uint64_t type and are in nanoseconds.

In reality methods with a timestamp argument actually receive a tuple
like (123456789,) as the timestamp argument.  This is due to a bug in
simpletrace.py.

This patch unpacks the tuple so that methods receive the correct
timestamp argument type.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 scripts/simpletrace.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/scripts/simpletrace.py b/scripts/simpletrace.py
index a3a6315055..be3d1affaf 100755
--- a/scripts/simpletrace.py
+++ b/scripts/simpletrace.py
@@ -199,7 +199,7 @@ def process(events, log, analyzer, read_header=True):
         fn_argcount = len(inspect.getargspec(fn)[0]) - 1
         if fn_argcount == event_argcount + 1:
             # Include timestamp as first argument
-            return lambda _, rec: fn(*((rec[1:2],) + rec[3:3 + event_argcount]))
+            return lambda _, rec: fn(*(rec[1:2] + rec[3:3 + event_argcount]))
         elif fn_argcount == event_argcount + 2:
             # Include timestamp and pid
             return lambda _, rec: fn(*rec[1:3 + event_argcount])
-- 
2.14.3