This change adjusts the profiling/tracing support so that the common

path (with no profile/trace function) through eval_code2() and
eval_frame() avoids several checks.

In the common cases of calls, returns, and exception propogation,
eval_code2() and eval_frame() used to test two values in the
thread-state: the profiling function and the tracing function.  With
this change, a flag is set in the thread-state if either of these is
active, allowing a single check to suffice when both are NULL.  This
also simplifies the code needed when either function is in use but is
already active (to avoid profiling/tracing the profiler/tracer); the
flag is set to 0 when the profile/trace code is entered, allowing the
same check to suffice for "already in the tracer" for call/return/
exception events.

1 files changed, 1 insertions, 0 deletions

diff --git a/Include/pystate.h b/Include/pystate.h
index d5e2e1f..15a264c 100644
--- a/Include/pystate.h
+++ b/Include/pystate.h
@@ -49,6 +49,7 @@ typedef struct _ts {
     int recursion_depth;
     int ticker;
     int tracing;
+    int use_tracing;
 
     Py_tracefunc c_profilefunc;
     Py_tracefunc c_tracefunc;