[pypy-svn] r16173 - pypy/dist/pypy/interpreter

[arigo at codespeak.net]

Author: arigo
Date: Fri Aug 19 19:14:21 2005
New Revision: 16173

Modified:
   pypy/dist/pypy/interpreter/baseobjspace.py
   pypy/dist/pypy/interpreter/executioncontext.py
   pypy/dist/pypy/interpreter/miscutils.py
Log:
A change in preparation for thread support (which remains completely
independent from the core): the 'space.threadlocals' object, which contained
the executioncontext, has now a well-defined method-based interface for
reading and setting the executioncontext and for "making a pause" between
bytecodes, for cooperative scheduling.

Thread strategies are implemented by patching 'space.threadlocals' to point to
an instance of a different class, with methods that really provide thread
support.  The default 'space.threadlocals' holds just a single
executioncontext, like before.  Patching is done in the init method of the
selected thread module.



Modified: pypy/dist/pypy/interpreter/baseobjspace.py
==============================================================================
--- pypy/dist/pypy/interpreter/baseobjspace.py	(original)
+++ pypy/dist/pypy/interpreter/baseobjspace.py	Fri Aug 19 19:14:21 2005
@@ -230,17 +230,17 @@
 
     def getexecutioncontext(self):
         "Return what we consider to be the active execution context."
-        ec = self.threadlocals.executioncontext
+        ec = self.threadlocals.getvalue()
         if ec is None:
             ec = self.createexecutioncontext()
-            self.threadlocals.executioncontext = ec
+            self.threadlocals.setvalue(ec)
         return ec
 
     def _freeze_(self):
         # Important: the annotator must not see a prebuilt ExecutionContext
         # for reasons related to the specialization of the framestack attribute
         # so we make sure there is no executioncontext at freeze-time
-        self.threadlocals.executioncontext = None
+        self.threadlocals.setvalue(None)
         return True 
 
     def createexecutioncontext(self):

Modified: pypy/dist/pypy/interpreter/executioncontext.py
==============================================================================
--- pypy/dist/pypy/interpreter/executioncontext.py	(original)
+++ pypy/dist/pypy/interpreter/executioncontext.py	Fri Aug 19 19:14:21 2005
@@ -20,7 +20,7 @@
                                  self.space.wrap("maximum recursion depth exceeded"))
         try:
             frame.f_back = self.framestack.top()
-        except:
+        except IndexError:
             frame.f_back = None
 
         if not frame.hide():
@@ -57,6 +57,7 @@
 
     def bytecode_trace(self, frame):
         "Trace function called before each bytecode."
+        self.space.threadlocals.yield_thread()
         if self.is_tracing or frame.w_f_trace is None:
             return
         code = getattr(frame, 'pycode')

Modified: pypy/dist/pypy/interpreter/miscutils.py
==============================================================================
--- pypy/dist/pypy/interpreter/miscutils.py	(original)
+++ pypy/dist/pypy/interpreter/miscutils.py	Fri Aug 19 19:14:21 2005
@@ -82,9 +82,20 @@
 
 
 class ThreadLocals:
-    """Thread-local storage."""
-    # XXX this is not really thread-local at the moment.
-    # XXX reconsider how this should be implemented when we add threads.
+    """Pseudo thread-local storage, for 'space.threadlocals'.
+    This is not really thread-local at all; the intention is that the PyPy
+    implementation of the 'thread' module knows how to provide a real
+    implementation for this feature, and patches 'space.threadlocals' when
+    'thread' is initialized.
+    """
+    _value = None
 
-    def __init__(self):
-        self.executioncontext = None
+    def getvalue(self):
+        return self._value
+
+    def setvalue(self, value):
+        self._value = value
+
+    def yield_thread(self):
+        """Called from time to time between the interpretation of bytecodes.
+        Hook for threading models that require it."""