Thread safe tips for python extending
In fact, the habit of using python write some single-threaded expansion, has not encountered such problems
Write a python today in the extension of the time encountered a problem. Through the python launched a c + + thread, the thread c + + will be a pullback python interface. Debugging has been for a long time is not aware of the security thread reasons, because c + + threads in the vm call python when the pyobject. thread is not safe. Therefore, when c + + threading operation vm directly to a certain object it is very wrong result.
I search the information in the http://www.python.org/dev/peps/pep-0311/ have talked about how the vm synchronous python. Two vm lock function can be done, and c + + thread synchronization. Is The so-called GIL (Global Interpreter Lock).
There are two ways to accomplish the following:
1. Py_BEGIN_ALLOW_THREADS, Py_END_ALLOW_THREADS this to Acer
2. PyGILState_Ensure and PyGILState_Release
But I Py_BEGIN_ALLOW_THREADS not seem useful, I will not have to get to the bottom, because PyGILState_Ensure enough. Do not have too much time to study the documents, to use the time to look back on.
I look at the sample code:
# Include "Python.h"
# Include "ceval.h"
Class PyGILHelper
(
Public:
PyGILHelper ():
MState (PyGILState_Ensure ())
(
)
~ PyGILHelper ()
(
PyGILState_Release (mState);
)
Protected:
PyGILState_STATE mState;
);
Usage is simple:
PyGILHelper lock;
/ / Some c api code
Tags: Thread