Windows: Use 32-bit distribution of python

python/gevent/_tracer.py

@@ -0,0 +1,179 @@
+# Copyright (c) 2018 gevent. See LICENSE for details.
+# cython: auto_pickle=False,embedsignature=True,always_allow_keywords=False
+from __future__ import print_function, absolute_import, division
+
+import sys
+import traceback
+
+from greenlet import settrace
+from greenlet import getcurrent
+
+from gevent.util import format_run_info
+
+from gevent._compat import perf_counter
+from gevent._util import gmctime
+
+
+__all__ = [
+    'GreenletTracer',
+    'HubSwitchTracer',
+    'MaxSwitchTracer',
+]
+
+# Recall these classes are cython compiled, so
+# class variable declarations are bad.
+
+
+class GreenletTracer(object):
+    def __init__(self):
+        # A counter, incremented by the greenlet trace function
+        # we install on every greenlet switch. This is reset when the
+        # periodic monitoring thread runs.
+
+        self.greenlet_switch_counter = 0
+
+        # The greenlet last switched to.
+        self.active_greenlet = None
+
+        # The trace function that was previously installed,
+        # if any.
+        # NOTE: Calling a class instance is cheaper than
+        # calling a bound method (at least when compiled with cython)
+        # even when it redirects to another function.
+        prev_trace = settrace(self)
+
+        self.previous_trace_function = prev_trace
+
+        self._killed = False
+
+    def kill(self):
+        # Must be called in the monitored thread.
+        if not self._killed:
+            self._killed = True
+            settrace(self.previous_trace_function)
+            self.previous_trace_function = None
+
+    def _trace(self, event, args):
+        # This function runs in the thread we are monitoring.
+        self.greenlet_switch_counter += 1
+        if event in ('switch', 'throw'):
+            # args is (origin, target). This is the only defined
+            # case
+            self.active_greenlet = args[1]
+        else:
+            self.active_greenlet = None
+        if self.previous_trace_function is not None:
+            self.previous_trace_function(event, args)
+
+    def __call__(self, event, args):
+        return self._trace(event, args)
+
+    def did_block_hub(self, hub):
+        # Check to see if we have blocked since the last call to this
+        # method. Returns a true value if we blocked (not in the hub),
+        # a false value if everything is fine.
+
+        # This may be called in the same thread being traced or a
+        # different thread; if a different thread, there is a race
+        # condition with this being incremented in the thread we're
+        # monitoring, but probably not often enough to lead to
+        # annoying false positives.
+
+        active_greenlet = self.active_greenlet
+        did_switch = self.greenlet_switch_counter != 0
+        self.greenlet_switch_counter = 0
+
+        if did_switch or active_greenlet is None or active_greenlet is hub:
+            # Either we switched, or nothing is running (we got a
+            # trace event we don't know about or were requested to
+            # ignore), or we spent the whole time in the hub, blocked
+            # for IO. Nothing to report.
+            return False
+        return True, active_greenlet
+
+    def ignore_current_greenlet_blocking(self):
+        # Don't pay attention to the current greenlet.
+        self.active_greenlet = None
+
+    def monitor_current_greenlet_blocking(self):
+        self.active_greenlet = getcurrent()
+
+    def did_block_hub_report(self, hub, active_greenlet, format_kwargs):
+        report = ['=' * 80,
+                  '\n%s : Greenlet %s appears to be blocked' %
+                  (gmctime(), active_greenlet)]
+        report.append("    Reported by %s" % (self,))
+        try:
+            frame = sys._current_frames()[hub.thread_ident]
+        except KeyError:
+            # The thread holding the hub has died. Perhaps we shouldn't
+            # even report this?
+            stack = ["Unknown: No thread found for hub %r\n" % (hub,)]
+        else:
+            stack = traceback.format_stack(frame)
+        report.append('Blocked Stack (for thread id %s):' % (hex(hub.thread_ident),))
+        report.append(''.join(stack))
+        report.append("Info:")
+        report.extend(format_run_info(**format_kwargs))
+
+        return report
+
+
+class _HubTracer(GreenletTracer):
+    def __init__(self, hub, max_blocking_time):
+        GreenletTracer.__init__(self)
+        self.max_blocking_time = max_blocking_time
+        self.hub = hub
+
+    def kill(self):
+        self.hub = None
+        GreenletTracer.kill(self)
+
+
+class HubSwitchTracer(_HubTracer):
+    # A greenlet tracer that records the last time we switched *into* the hub.
+
+    def __init__(self, hub, max_blocking_time):
+        _HubTracer.__init__(self, hub, max_blocking_time)
+        self.last_entered_hub = 0
+
+    def _trace(self, event, args):
+        GreenletTracer._trace(self, event, args)
+        if self.active_greenlet is self.hub:
+            self.last_entered_hub = perf_counter()
+
+    def did_block_hub(self, hub):
+        if perf_counter() - self.last_entered_hub > self.max_blocking_time:
+            return True, self.active_greenlet
+
+
+class MaxSwitchTracer(_HubTracer):
+    # A greenlet tracer that records the maximum time between switches,
+    # not including time spent in the hub.
+
+    def __init__(self, hub, max_blocking_time):
+        _HubTracer.__init__(self, hub, max_blocking_time)
+        self.last_switch = perf_counter()
+        self.max_blocking = 0
+
+    def _trace(self, event, args):
+        old_active = self.active_greenlet
+        GreenletTracer._trace(self, event, args)
+        if old_active is not self.hub and old_active is not None:
+            # If we're switching out of the hub, the blocking
+            # time doesn't count.
+            switched_at = perf_counter()
+            self.max_blocking = max(self.max_blocking,
+                                    switched_at - self.last_switch)
+
+    def did_block_hub(self, hub):
+        if self.max_blocking == 0:
+            # We never switched. Check the time now
+            self.max_blocking = perf_counter() - self.last_switch
+
+        if self.max_blocking > self.max_blocking_time:
+            return True, self.active_greenlet
+
+
+from gevent._util import import_c_accel
+import_c_accel(globals(), 'gevent.__tracer')