buildtools/wafsamba/nothreads.py

   1 #!/usr/bin/env python
   2 # encoding: utf-8
   3 # Thomas Nagy, 2005-2008 (ita)
   4
   5 # this replaces the core of Runner.py in waf with a varient that works
   6 # on systems with completely broken threading (such as Python 2.5.x on
   7 # AIX). For simplicity we enable this when JOBS=1, which is triggered
   8 # by the compatibility makefile used for the waf build. That also ensures
   9 # this code is tested, as it means it is used in the build farm, and by
  10 # anyone using 'make' to build Samba with waf
  11
  12 "Execute the tasks"
  13
  14 import sys, random, time, threading, traceback, os
  15 try: from Queue import Queue
  16 except ImportError: from queue import Queue
  17 import Build, Utils, Logs, Options
  18 from Logs import debug, error
  19 from Constants import *
  20
  21 GAP = 15
  22
  23 run_old = threading.Thread.run
  24 def run(*args, **kwargs):
  25     try:
  26         run_old(*args, **kwargs)
  27     except (KeyboardInterrupt, SystemExit):
  28         raise
  29     except:
  30         sys.excepthook(*sys.exc_info())
  31 threading.Thread.run = run
  32
  33
  34 class TaskConsumer(object):
  35     consumers = 1
  36
  37 def process(tsk):
  38     m = tsk.master
  39     if m.stop:
  40         m.out.put(tsk)
  41         return
  42
  43     try:
  44         tsk.generator.bld.printout(tsk.display())
  45         if tsk.__class__.stat: ret = tsk.__class__.stat(tsk)
  46         # actual call to task's run() function
  47         else: ret = tsk.call_run()
  48     except Exception, e:
  49         tsk.err_msg = Utils.ex_stack()
  50         tsk.hasrun = EXCEPTION
  51
  52         # TODO cleanup
  53         m.error_handler(tsk)
  54         m.out.put(tsk)
  55         return
  56
  57     if ret:
  58         tsk.err_code = ret
  59         tsk.hasrun = CRASHED
  60     else:
  61         try:
  62             tsk.post_run()
  63         except Utils.WafError:
  64             pass
  65         except Exception:
  66             tsk.err_msg = Utils.ex_stack()
  67             tsk.hasrun = EXCEPTION
  68         else:
  69             tsk.hasrun = SUCCESS
  70     if tsk.hasrun != SUCCESS:
  71         m.error_handler(tsk)
  72
  73     m.out.put(tsk)
  74
  75 class Parallel(object):
  76     """
  77     keep the consumer threads busy, and avoid consuming cpu cycles
  78     when no more tasks can be added (end of the build, etc)
  79     """
  80     def __init__(self, bld, j=2):
  81
  82         # number of consumers
  83         self.numjobs = j
  84
  85         self.manager = bld.task_manager
  86         self.manager.current_group = 0
  87
  88         self.total = self.manager.total()
  89
  90         # tasks waiting to be processed - IMPORTANT
  91         self.outstanding = []
  92         self.maxjobs = MAXJOBS
  93
  94         # tasks that are awaiting for another task to complete
  95         self.frozen = []
  96
  97         # tasks returned by the consumers
  98         self.out = Queue(0)
  99
 100         self.count = 0 # tasks not in the producer area
 101
 102         self.processed = 1 # progress indicator
 103
 104         self.stop = False # error condition to stop the build
 105         self.error = False # error flag
 106
 107     def get_next(self):
 108         "override this method to schedule the tasks in a particular order"
 109         if not self.outstanding:
 110             return None
 111         return self.outstanding.pop(0)
 112
 113     def postpone(self, tsk):
 114         "override this method to schedule the tasks in a particular order"
 115         # TODO consider using a deque instead
 116         if random.randint(0, 1):
 117             self.frozen.insert(0, tsk)
 118         else:
 119             self.frozen.append(tsk)
 120
 121     def refill_task_list(self):
 122         "called to set the next group of tasks"
 123
 124         while self.count > self.numjobs + GAP or self.count >= self.maxjobs:
 125             self.get_out()
 126
 127         while not self.outstanding:
 128             if self.count:
 129                 self.get_out()
 130
 131             if self.frozen:
 132                 self.outstanding += self.frozen
 133                 self.frozen = []
 134             elif not self.count:
 135                 (jobs, tmp) = self.manager.get_next_set()
 136                 if jobs != None: self.maxjobs = jobs
 137                 if tmp: self.outstanding += tmp
 138                 break
 139
 140     def get_out(self):
 141         "the tasks that are put to execute are all collected using get_out"
 142         ret = self.out.get()
 143         self.manager.add_finished(ret)
 144         if not self.stop and getattr(ret, 'more_tasks', None):
 145             self.outstanding += ret.more_tasks
 146             self.total += len(ret.more_tasks)
 147         self.count -= 1
 148
 149     def error_handler(self, tsk):
 150         "by default, errors make the build stop (not thread safe so be careful)"
 151         if not Options.options.keep:
 152             self.stop = True
 153         self.error = True
 154
 155     def start(self):
 156         "execute the tasks"
 157
 158         while not self.stop:
 159
 160             self.refill_task_list()
 161
 162             # consider the next task
 163             tsk = self.get_next()
 164             if not tsk:
 165                 if self.count:
 166                     # tasks may add new ones after they are run
 167                     continue
 168                 else:
 169                     # no tasks to run, no tasks running, time to exit
 170                     break
 171
 172             if tsk.hasrun:
 173                 # if the task is marked as "run", just skip it
 174                 self.processed += 1
 175                 self.manager.add_finished(tsk)
 176                 continue
 177
 178             try:
 179                 st = tsk.runnable_status()
 180             except Exception, e:
 181                 self.processed += 1
 182                 if self.stop and not Options.options.keep:
 183                     tsk.hasrun = SKIPPED
 184                     self.manager.add_finished(tsk)
 185                     continue
 186                 self.error_handler(tsk)
 187                 self.manager.add_finished(tsk)
 188                 tsk.hasrun = EXCEPTION
 189                 tsk.err_msg = Utils.ex_stack()
 190                 continue
 191
 192             if st == ASK_LATER:
 193                 self.postpone(tsk)
 194             elif st == SKIP_ME:
 195                 self.processed += 1
 196                 tsk.hasrun = SKIPPED
 197                 self.manager.add_finished(tsk)
 198             else:
 199                 # run me: put the task in ready queue
 200                 tsk.position = (self.processed, self.total)
 201                 self.count += 1
 202                 self.processed += 1
 203                 tsk.master = self
 204
 205                 process(tsk)
 206
 207         # self.count represents the tasks that have been made available to the consumer threads
 208         # collect all the tasks after an error else the message may be incomplete
 209         while self.error and self.count:
 210             self.get_out()
 211
 212         #print loop
 213         assert (self.count == 0 or self.stop)
 214
 215
 216 # enable nothreads
 217 import Runner
 218 Runner.process = process
 219 Runner.Parallel = Parallel