diff --git a/meta/poky/bitbake/lib/bb/runqueue.py b/meta/poky/bitbake/lib/bb/runqueue.py
new file mode 100644
index 0000000..383c183
--- /dev/null
+++ b/meta/poky/bitbake/lib/bb/runqueue.py
@@ -0,0 +1,2756 @@
+#!/usr/bin/env python
+# ex:ts=4:sw=4:sts=4:et
+# -*- tab-width: 4; c-basic-offset: 4; indent-tabs-mode: nil -*-
+"""
+BitBake 'RunQueue' implementation
+
+Handles preparation and execution of a queue of tasks
+"""
+
+# Copyright (C) 2006-2007  Richard Purdie
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License version 2 as
+# published by the Free Software Foundation.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License along
+# with this program; if not, write to the Free Software Foundation, Inc.,
+# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+
+import copy
+import os
+import sys
+import signal
+import stat
+import fcntl
+import errno
+import logging
+import re
+import bb
+from bb import msg, data, event
+from bb import monitordisk
+import subprocess
+import pickle
+from multiprocessing import Process
+
+bblogger = logging.getLogger("BitBake")
+logger = logging.getLogger("BitBake.RunQueue")
+
+__find_md5__ = re.compile( r'(?i)(?<![a-z0-9])[a-f0-9]{32}(?![a-z0-9])' )
+
+def fn_from_tid(tid):
+     return tid.rsplit(":", 1)[0]
+
+def taskname_from_tid(tid):
+    return tid.rsplit(":", 1)[1]
+
+def mc_from_tid(tid):
+    if tid.startswith('multiconfig:'):
+        return tid.split(':')[1]
+    return ""
+
+def split_tid(tid):
+    (mc, fn, taskname, _) = split_tid_mcfn(tid)
+    return (mc, fn, taskname)
+
+def split_tid_mcfn(tid):
+    if tid.startswith('multiconfig:'):
+        elems = tid.split(':')
+        mc = elems[1]
+        fn = ":".join(elems[2:-1])
+        taskname = elems[-1]
+        mcfn = "multiconfig:" + mc + ":" + fn
+    else:
+        tid = tid.rsplit(":", 1)
+        mc = ""
+        fn = tid[0]
+        taskname = tid[1]
+        mcfn = fn
+
+    return (mc, fn, taskname, mcfn)
+
+def build_tid(mc, fn, taskname):
+    if mc:
+        return "multiconfig:" + mc + ":" + fn + ":" + taskname
+    return fn + ":" + taskname
+
+class RunQueueStats:
+    """
+    Holds statistics on the tasks handled by the associated runQueue
+    """
+    def __init__(self, total):
+        self.completed = 0
+        self.skipped = 0
+        self.failed = 0
+        self.active = 0
+        self.total = total
+
+    def copy(self):
+        obj = self.__class__(self.total)
+        obj.__dict__.update(self.__dict__)
+        return obj
+
+    def taskFailed(self):
+        self.active = self.active - 1
+        self.failed = self.failed + 1
+
+    def taskCompleted(self):
+        self.active = self.active - 1
+        self.completed = self.completed + 1
+
+    def taskSkipped(self):
+        self.active = self.active + 1
+        self.skipped = self.skipped + 1
+
+    def taskActive(self):
+        self.active = self.active + 1
+
+# These values indicate the next step due to be run in the
+# runQueue state machine
+runQueuePrepare = 2
+runQueueSceneInit = 3
+runQueueSceneRun = 4
+runQueueRunInit = 5
+runQueueRunning = 6
+runQueueFailed = 7
+runQueueCleanUp = 8
+runQueueComplete = 9
+
+class RunQueueScheduler(object):
+    """
+    Control the order tasks are scheduled in.
+    """
+    name = "basic"
+
+    def __init__(self, runqueue, rqdata):
+        """
+        The default scheduler just returns the first buildable task (the
+        priority map is sorted by task number)
+        """
+        self.rq = runqueue
+        self.rqdata = rqdata
+        self.numTasks = len(self.rqdata.runtaskentries)
+
+        self.prio_map = [self.rqdata.runtaskentries.keys()]
+
+        self.buildable = []
+        self.skip_maxthread = {}
+        self.stamps = {}
+        for tid in self.rqdata.runtaskentries:
+            (mc, fn, taskname, taskfn) = split_tid_mcfn(tid)
+            self.stamps[tid] = bb.build.stampfile(taskname, self.rqdata.dataCaches[mc], taskfn, noextra=True)
+            if tid in self.rq.runq_buildable:
+                self.buildable.append(tid)
+
+        self.rev_prio_map = None
+
+    def next_buildable_task(self):
+        """
+        Return the id of the first task we find that is buildable
+        """
+        self.buildable = [x for x in self.buildable if x not in self.rq.runq_running]
+        if not self.buildable:
+            return None
+
+        # Filter out tasks that have a max number of threads that have been exceeded
+        skip_buildable = {}
+        for running in self.rq.runq_running.difference(self.rq.runq_complete):
+            rtaskname = taskname_from_tid(running)
+            if rtaskname not in self.skip_maxthread:
+                self.skip_maxthread[rtaskname] = self.rq.cfgData.getVarFlag(rtaskname, "number_threads")
+            if not self.skip_maxthread[rtaskname]:
+                continue
+            if rtaskname in skip_buildable:
+                skip_buildable[rtaskname] += 1
+            else:
+                skip_buildable[rtaskname] = 1
+
+        if len(self.buildable) == 1:
+            tid = self.buildable[0]
+            taskname = taskname_from_tid(tid)
+            if taskname in skip_buildable and skip_buildable[taskname] >= int(self.skip_maxthread[taskname]):
+                return None
+            stamp = self.stamps[tid]
+            if stamp not in self.rq.build_stamps.values():
+                return tid
+
+        if not self.rev_prio_map:
+            self.rev_prio_map = {}
+            for tid in self.rqdata.runtaskentries:
+                self.rev_prio_map[tid] = self.prio_map.index(tid)
+
+        best = None
+        bestprio = None
+        for tid in self.buildable:
+            taskname = taskname_from_tid(tid)
+            if taskname in skip_buildable and skip_buildable[taskname] >= int(self.skip_maxthread[taskname]):
+                continue
+            prio = self.rev_prio_map[tid]
+            if bestprio is None or bestprio > prio:
+                stamp = self.stamps[tid]
+                if stamp in self.rq.build_stamps.values():
+                    continue
+                bestprio = prio
+                best = tid
+
+        return best
+
+    def next(self):
+        """
+        Return the id of the task we should build next
+        """
+        if self.rq.can_start_task():
+            return self.next_buildable_task()
+
+    def newbuildable(self, task):
+        self.buildable.append(task)
+
+    def describe_task(self, taskid):
+        result = 'ID %s' % taskid
+        if self.rev_prio_map:
+            result = result + (' pri %d' % self.rev_prio_map[taskid])
+        return result
+
+    def dump_prio(self, comment):
+        bb.debug(3, '%s (most important first):\n%s' %
+                 (comment,
+                  '\n'.join(['%d. %s' % (index + 1, self.describe_task(taskid)) for
+                             index, taskid in enumerate(self.prio_map)])))
+
+class RunQueueSchedulerSpeed(RunQueueScheduler):
+    """
+    A scheduler optimised for speed. The priority map is sorted by task weight,
+    heavier weighted tasks (tasks needed by the most other tasks) are run first.
+    """
+    name = "speed"
+
+    def __init__(self, runqueue, rqdata):
+        """
+        The priority map is sorted by task weight.
+        """
+        RunQueueScheduler.__init__(self, runqueue, rqdata)
+
+        weights = {}
+        for tid in self.rqdata.runtaskentries:
+            weight = self.rqdata.runtaskentries[tid].weight
+            if not weight in weights:
+                weights[weight] = []
+            weights[weight].append(tid)
+
+        self.prio_map = []
+        for weight in sorted(weights):
+            for w in weights[weight]:
+                self.prio_map.append(w)
+
+        self.prio_map.reverse()
+
+class RunQueueSchedulerCompletion(RunQueueSchedulerSpeed):
+    """
+    A scheduler optimised to complete .bb files as quickly as possible. The
+    priority map is sorted by task weight, but then reordered so once a given
+    .bb file starts to build, it's completed as quickly as possible by
+    running all tasks related to the same .bb file one after the after.
+    This works well where disk space is at a premium and classes like OE's
+    rm_work are in force.
+    """
+    name = "completion"
+
+    def __init__(self, runqueue, rqdata):
+        super(RunQueueSchedulerCompletion, self).__init__(runqueue, rqdata)
+
+        # Extract list of tasks for each recipe, with tasks sorted
+        # ascending from "must run first" (typically do_fetch) to
+        # "runs last" (do_build). The speed scheduler prioritizes
+        # tasks that must run first before the ones that run later;
+        # this is what we depend on here.
+        task_lists = {}
+        for taskid in self.prio_map:
+            fn, taskname = taskid.rsplit(':', 1)
+            task_lists.setdefault(fn, []).append(taskname)
+
+        # Now unify the different task lists. The strategy is that
+        # common tasks get skipped and new ones get inserted after the
+        # preceeding common one(s) as they are found. Because task
+        # lists should differ only by their number of tasks, but not
+        # the ordering of the common tasks, this should result in a
+        # deterministic result that is a superset of the individual
+        # task ordering.
+        all_tasks = []
+        for recipe, new_tasks in task_lists.items():
+            index = 0
+            old_task = all_tasks[index] if index < len(all_tasks) else None
+            for new_task in new_tasks:
+                if old_task == new_task:
+                    # Common task, skip it. This is the fast-path which
+                    # avoids a full search.
+                    index += 1
+                    old_task = all_tasks[index] if index < len(all_tasks) else None
+                else:
+                    try:
+                        index = all_tasks.index(new_task)
+                        # Already present, just not at the current
+                        # place. We re-synchronized by changing the
+                        # index so that it matches again. Now
+                        # move on to the next existing task.
+                        index += 1
+                        old_task = all_tasks[index] if index < len(all_tasks) else None
+                    except ValueError:
+                        # Not present. Insert before old_task, which
+                        # remains the same (but gets shifted back).
+                        all_tasks.insert(index, new_task)
+                        index += 1
+        bb.debug(3, 'merged task list: %s'  % all_tasks)
+
+        # Now reverse the order so that tasks that finish the work on one
+        # recipe are considered more imporant (= come first). The ordering
+        # is now so that do_build is most important.
+        all_tasks.reverse()
+
+        # Group tasks of the same kind before tasks of less important
+        # kinds at the head of the queue (because earlier = lower
+        # priority number = runs earlier), while preserving the
+        # ordering by recipe. If recipe foo is more important than
+        # bar, then the goal is to work on foo's do_populate_sysroot
+        # before bar's do_populate_sysroot and on the more important
+        # tasks of foo before any of the less important tasks in any
+        # other recipe (if those other recipes are more important than
+        # foo).
+        #
+        # All of this only applies when tasks are runable. Explicit
+        # dependencies still override this ordering by priority.
+        #
+        # Here's an example why this priority re-ordering helps with
+        # minimizing disk usage. Consider a recipe foo with a higher
+        # priority than bar where foo DEPENDS on bar. Then the
+        # implicit rule (from base.bbclass) is that foo's do_configure
+        # depends on bar's do_populate_sysroot. This ensures that
+        # bar's do_populate_sysroot gets done first. Normally the
+        # tasks from foo would continue to run once that is done, and
+        # bar only gets completed and cleaned up later. By ordering
+        # bar's task that depend on bar's do_populate_sysroot before foo's
+        # do_configure, that problem gets avoided.
+        task_index = 0
+        self.dump_prio('original priorities')
+        for task in all_tasks:
+            for index in range(task_index, self.numTasks):
+                taskid = self.prio_map[index]
+                taskname = taskid.rsplit(':', 1)[1]
+                if taskname == task:
+                    del self.prio_map[index]
+                    self.prio_map.insert(task_index, taskid)
+                    task_index += 1
+        self.dump_prio('completion priorities')
+
+class RunTaskEntry(object):
+    def __init__(self):
+        self.depends = set()
+        self.revdeps = set()
+        self.hash = None
+        self.task = None
+        self.weight = 1
+
+class RunQueueData:
+    """
+    BitBake Run Queue implementation
+    """
+    def __init__(self, rq, cooker, cfgData, dataCaches, taskData, targets):
+        self.cooker = cooker
+        self.dataCaches = dataCaches
+        self.taskData = taskData
+        self.targets = targets
+        self.rq = rq
+        self.warn_multi_bb = False
+
+        self.stampwhitelist = cfgData.getVar("BB_STAMP_WHITELIST") or ""
+        self.multi_provider_whitelist = (cfgData.getVar("MULTI_PROVIDER_WHITELIST") or "").split()
+        self.setscenewhitelist = get_setscene_enforce_whitelist(cfgData)
+        self.setscenewhitelist_checked = False
+        self.setscene_enforce = (cfgData.getVar('BB_SETSCENE_ENFORCE') == "1")
+        self.init_progress_reporter = bb.progress.DummyMultiStageProcessProgressReporter()
+
+        self.reset()
+
+    def reset(self):
+        self.runtaskentries = {}
+
+    def runq_depends_names(self, ids):
+        import re
+        ret = []
+        for id in ids:
+            nam = os.path.basename(id)
+            nam = re.sub("_[^,]*,", ",", nam)
+            ret.extend([nam])
+        return ret
+
+    def get_task_hash(self, tid):
+        return self.runtaskentries[tid].hash
+
+    def get_user_idstring(self, tid, task_name_suffix = ""):
+        return tid + task_name_suffix
+
+    def get_short_user_idstring(self, task, task_name_suffix = ""):
+        (mc, fn, taskname, taskfn) = split_tid_mcfn(task)
+        pn = self.dataCaches[mc].pkg_fn[taskfn]
+        taskname = taskname_from_tid(task) + task_name_suffix
+        return "%s:%s" % (pn, taskname)
+
+    def circular_depchains_handler(self, tasks):
+        """
+        Some tasks aren't buildable, likely due to circular dependency issues.
+        Identify the circular dependencies and print them in a user readable format.
+        """
+        from copy import deepcopy
+
+        valid_chains = []
+        explored_deps = {}
+        msgs = []
+
+        class TooManyLoops(Exception):
+            pass
+
+        def chain_reorder(chain):
+            """
+            Reorder a dependency chain so the lowest task id is first
+            """
+            lowest = 0
+            new_chain = []
+            for entry in range(len(chain)):
+                if chain[entry] < chain[lowest]:
+                    lowest = entry
+            new_chain.extend(chain[lowest:])
+            new_chain.extend(chain[:lowest])
+            return new_chain
+
+        def chain_compare_equal(chain1, chain2):
+            """
+            Compare two dependency chains and see if they're the same
+            """
+            if len(chain1) != len(chain2):
+                return False
+            for index in range(len(chain1)):
+                if chain1[index] != chain2[index]:
+                    return False
+            return True
+
+        def chain_array_contains(chain, chain_array):
+            """
+            Return True if chain_array contains chain
+            """
+            for ch in chain_array:
+                if chain_compare_equal(ch, chain):
+                    return True
+            return False
+
+        def find_chains(tid, prev_chain):
+            prev_chain.append(tid)
+            total_deps = []
+            total_deps.extend(self.runtaskentries[tid].revdeps)
+            for revdep in self.runtaskentries[tid].revdeps:
+                if revdep in prev_chain:
+                    idx = prev_chain.index(revdep)
+                    # To prevent duplicates, reorder the chain to start with the lowest taskid
+                    # and search through an array of those we've already printed
+                    chain = prev_chain[idx:]
+                    new_chain = chain_reorder(chain)
+                    if not chain_array_contains(new_chain, valid_chains):
+                        valid_chains.append(new_chain)
+                        msgs.append("Dependency loop #%d found:\n" % len(valid_chains))
+                        for dep in new_chain:
+                            msgs.append("  Task %s (dependent Tasks %s)\n" % (dep, self.runq_depends_names(self.runtaskentries[dep].depends)))
+                        msgs.append("\n")
+                    if len(valid_chains) > 10:
+                        msgs.append("Aborted dependency loops search after 10 matches.\n")
+                        raise TooManyLoops
+                    continue
+                scan = False
+                if revdep not in explored_deps:
+                    scan = True
+                elif revdep in explored_deps[revdep]:
+                    scan = True
+                else:
+                    for dep in prev_chain:
+                        if dep in explored_deps[revdep]:
+                            scan = True
+                if scan:
+                    find_chains(revdep, copy.deepcopy(prev_chain))
+                for dep in explored_deps[revdep]:
+                    if dep not in total_deps:
+                        total_deps.append(dep)
+
+            explored_deps[tid] = total_deps
+
+        try:
+            for task in tasks:
+                find_chains(task, [])
+        except TooManyLoops:
+            pass
+
+        return msgs
+
+    def calculate_task_weights(self, endpoints):
+        """
+        Calculate a number representing the "weight" of each task. Heavier weighted tasks
+        have more dependencies and hence should be executed sooner for maximum speed.
+
+        This function also sanity checks the task list finding tasks that are not
+        possible to execute due to circular dependencies.
+        """
+
+        numTasks = len(self.runtaskentries)
+        weight = {}
+        deps_left = {}
+        task_done = {}
+
+        for tid in self.runtaskentries:
+            task_done[tid] = False
+            weight[tid] = 1
+            deps_left[tid] = len(self.runtaskentries[tid].revdeps)
+
+        for tid in endpoints:
+            weight[tid] = 10
+            task_done[tid] = True
+
+        while True:
+            next_points = []
+            for tid in endpoints:
+                for revdep in self.runtaskentries[tid].depends:
+                    weight[revdep] = weight[revdep] + weight[tid]
+                    deps_left[revdep] = deps_left[revdep] - 1
+                    if deps_left[revdep] == 0:
+                        next_points.append(revdep)
+                        task_done[revdep] = True
+            endpoints = next_points
+            if len(next_points) == 0:
+                break
+
+        # Circular dependency sanity check
+        problem_tasks = []
+        for tid in self.runtaskentries:
+            if task_done[tid] is False or deps_left[tid] != 0:
+                problem_tasks.append(tid)
+                logger.debug(2, "Task %s is not buildable", tid)
+                logger.debug(2, "(Complete marker was %s and the remaining dependency count was %s)\n", task_done[tid], deps_left[tid])
+            self.runtaskentries[tid].weight = weight[tid]
+
+        if problem_tasks:
+            message = "%s unbuildable tasks were found.\n" % len(problem_tasks)
+            message = message + "These are usually caused by circular dependencies and any circular dependency chains found will be printed below. Increase the debug level to see a list of unbuildable tasks.\n\n"
+            message = message + "Identifying dependency loops (this may take a short while)...\n"
+            logger.error(message)
+
+            msgs = self.circular_depchains_handler(problem_tasks)
+
+            message = "\n"
+            for msg in msgs:
+                message = message + msg
+            bb.msg.fatal("RunQueue", message)
+
+        return weight
+
+    def prepare(self):
+        """
+        Turn a set of taskData into a RunQueue and compute data needed
+        to optimise the execution order.
+        """
+
+        runq_build = {}
+        recursivetasks = {}
+        recursiveitasks = {}
+        recursivetasksselfref = set()
+
+        taskData = self.taskData
+
+        found = False
+        for mc in self.taskData:
+            if len(taskData[mc].taskentries) > 0:
+                found = True
+                break
+        if not found:
+            # Nothing to do
+            return 0
+
+        self.init_progress_reporter.start()
+        self.init_progress_reporter.next_stage()
+
+        # Step A - Work out a list of tasks to run
+        #
+        # Taskdata gives us a list of possible providers for every build and run
+        # target ordered by priority. It also gives information on each of those
+        # providers.
+        #
+        # To create the actual list of tasks to execute we fix the list of
+        # providers and then resolve the dependencies into task IDs. This
+        # process is repeated for each type of dependency (tdepends, deptask,
+        # rdeptast, recrdeptask, idepends).
+
+        def add_build_dependencies(depids, tasknames, depends, mc):
+            for depname in depids:
+                # Won't be in build_targets if ASSUME_PROVIDED
+                if depname not in taskData[mc].build_targets or not taskData[mc].build_targets[depname]:
+                    continue
+                depdata = taskData[mc].build_targets[depname][0]
+                if depdata is None:
+                    continue
+                for taskname in tasknames:
+                    t = depdata + ":" + taskname
+                    if t in taskData[mc].taskentries:
+                        depends.add(t)
+
+        def add_runtime_dependencies(depids, tasknames, depends, mc):
+            for depname in depids:
+                if depname not in taskData[mc].run_targets or not taskData[mc].run_targets[depname]:
+                    continue
+                depdata = taskData[mc].run_targets[depname][0]
+                if depdata is None:
+                    continue
+                for taskname in tasknames:
+                    t = depdata + ":" + taskname
+                    if t in taskData[mc].taskentries:
+                        depends.add(t)
+
+        def add_mc_dependencies(mc, tid):
+            mcdeps = taskData[mc].get_mcdepends()
+            for dep in mcdeps:
+                mcdependency = dep.split(':')
+                pn = mcdependency[3]
+                frommc = mcdependency[1]
+                mcdep = mcdependency[2]
+                deptask = mcdependency[4]
+                if mc == frommc:
+                    fn = taskData[mcdep].build_targets[pn][0]
+                    newdep = '%s:%s' % (fn,deptask)
+                    taskData[mc].taskentries[tid].tdepends.append(newdep)
+
+        for mc in taskData:
+            for tid in taskData[mc].taskentries:
+
+                (mc, fn, taskname, taskfn) = split_tid_mcfn(tid)
+                #runtid = build_tid(mc, fn, taskname)
+
+                #logger.debug(2, "Processing %s,%s:%s", mc, fn, taskname)
+
+                depends = set()
+                task_deps = self.dataCaches[mc].task_deps[taskfn]
+
+                self.runtaskentries[tid] = RunTaskEntry()
+
+                if fn in taskData[mc].failed_fns:
+                    continue
+
+                # We add multiconfig dependencies before processing internal task deps (tdepends)
+                if 'mcdepends' in task_deps and taskname in task_deps['mcdepends']:
+                    add_mc_dependencies(mc, tid)
+
+                # Resolve task internal dependencies
+                #
+                # e.g. addtask before X after Y
+                for t in taskData[mc].taskentries[tid].tdepends:
+                    (depmc, depfn, deptaskname, _) = split_tid_mcfn(t)
+                    depends.add(build_tid(depmc, depfn, deptaskname))
+
+                # Resolve 'deptask' dependencies
+                #
+                # e.g. do_sometask[deptask] = "do_someothertask"
+                # (makes sure sometask runs after someothertask of all DEPENDS)
+                if 'deptask' in task_deps and taskname in task_deps['deptask']:
+                    tasknames = task_deps['deptask'][taskname].split()
+                    add_build_dependencies(taskData[mc].depids[taskfn], tasknames, depends, mc)
+
+                # Resolve 'rdeptask' dependencies
+                #
+                # e.g. do_sometask[rdeptask] = "do_someothertask"
+                # (makes sure sometask runs after someothertask of all RDEPENDS)
+                if 'rdeptask' in task_deps and taskname in task_deps['rdeptask']:
+                    tasknames = task_deps['rdeptask'][taskname].split()
+                    add_runtime_dependencies(taskData[mc].rdepids[taskfn], tasknames, depends, mc)
+
+                # Resolve inter-task dependencies
+                #
+                # e.g. do_sometask[depends] = "targetname:do_someothertask"
+                # (makes sure sometask runs after targetname's someothertask)
+                idepends = taskData[mc].taskentries[tid].idepends
+                for (depname, idependtask) in idepends:
+                    if depname in taskData[mc].build_targets and taskData[mc].build_targets[depname] and not depname in taskData[mc].failed_deps:
+                        # Won't be in build_targets if ASSUME_PROVIDED
+                        depdata = taskData[mc].build_targets[depname][0]
+                        if depdata is not None:
+                            t = depdata + ":" + idependtask
+                            depends.add(t)
+                            if t not in taskData[mc].taskentries:
+                                bb.msg.fatal("RunQueue", "Task %s in %s depends upon non-existent task %s in %s" % (taskname, fn, idependtask, depdata))
+                irdepends = taskData[mc].taskentries[tid].irdepends
+                for (depname, idependtask) in irdepends:
+                    if depname in taskData[mc].run_targets:
+                        # Won't be in run_targets if ASSUME_PROVIDED
+                        if not taskData[mc].run_targets[depname]:
+                            continue
+                        depdata = taskData[mc].run_targets[depname][0]
+                        if depdata is not None:
+                            t = depdata + ":" + idependtask
+                            depends.add(t)
+                            if t not in taskData[mc].taskentries:
+                                bb.msg.fatal("RunQueue", "Task %s in %s rdepends upon non-existent task %s in %s" % (taskname, fn, idependtask, depdata))
+
+                # Resolve recursive 'recrdeptask' dependencies (Part A)
+                #
+                # e.g. do_sometask[recrdeptask] = "do_someothertask"
+                # (makes sure sometask runs after someothertask of all DEPENDS, RDEPENDS and intertask dependencies, recursively)
+                # We cover the recursive part of the dependencies below
+                if 'recrdeptask' in task_deps and taskname in task_deps['recrdeptask']:
+                    tasknames = task_deps['recrdeptask'][taskname].split()
+                    recursivetasks[tid] = tasknames
+                    add_build_dependencies(taskData[mc].depids[taskfn], tasknames, depends, mc)
+                    add_runtime_dependencies(taskData[mc].rdepids[taskfn], tasknames, depends, mc)
+                    if taskname in tasknames:
+                        recursivetasksselfref.add(tid)
+
+                    if 'recideptask' in task_deps and taskname in task_deps['recideptask']:
+                        recursiveitasks[tid] = []
+                        for t in task_deps['recideptask'][taskname].split():
+                            newdep = build_tid(mc, fn, t)
+                            recursiveitasks[tid].append(newdep)
+
+                self.runtaskentries[tid].depends = depends
+                # Remove all self references
+                self.runtaskentries[tid].depends.discard(tid)
+
+        #self.dump_data()
+
+        self.init_progress_reporter.next_stage()
+
+        # Resolve recursive 'recrdeptask' dependencies (Part B)
+        #
+        # e.g. do_sometask[recrdeptask] = "do_someothertask"
+        # (makes sure sometask runs after someothertask of all DEPENDS, RDEPENDS and intertask dependencies, recursively)
+        # We need to do this separately since we need all of runtaskentries[*].depends to be complete before this is processed
+
+        # Generating/interating recursive lists of dependencies is painful and potentially slow
+        # Precompute recursive task dependencies here by:
+        #     a) create a temp list of reverse dependencies (revdeps)
+        #     b) walk up the ends of the chains (when a given task no longer has dependencies i.e. len(deps) == 0)
+        #     c) combine the total list of dependencies in cumulativedeps
+        #     d) optimise by pre-truncating 'task' off the items in cumulativedeps (keeps items in sets lower)
+
+
+        revdeps = {}
+        deps = {}
+        cumulativedeps = {}
+        for tid in self.runtaskentries:
+            deps[tid] = set(self.runtaskentries[tid].depends)
+            revdeps[tid] = set()
+            cumulativedeps[tid] = set()
+        # Generate a temp list of reverse dependencies
+        for tid in self.runtaskentries:
+            for dep in self.runtaskentries[tid].depends:
+                revdeps[dep].add(tid)
+        # Find the dependency chain endpoints
+        endpoints = set()
+        for tid in self.runtaskentries:
+            if len(deps[tid]) == 0:
+                endpoints.add(tid)
+        # Iterate the chains collating dependencies
+        while endpoints:
+            next = set()
+            for tid in endpoints:
+                for dep in revdeps[tid]:
+                    cumulativedeps[dep].add(fn_from_tid(tid))
+                    cumulativedeps[dep].update(cumulativedeps[tid])
+                    if tid in deps[dep]:
+                        deps[dep].remove(tid)
+                    if len(deps[dep]) == 0:
+                        next.add(dep)
+            endpoints = next
+        #for tid in deps:
+        #    if len(deps[tid]) != 0:
+        #        bb.warn("Sanity test failure, dependencies left for %s (%s)" % (tid, deps[tid]))
+
+        # Loop here since recrdeptasks can depend upon other recrdeptasks and we have to
+        # resolve these recursively until we aren't adding any further extra dependencies
+        extradeps = True
+        while extradeps:
+            extradeps = 0
+            for tid in recursivetasks:
+                tasknames = recursivetasks[tid]
+
+                totaldeps = set(self.runtaskentries[tid].depends)
+                if tid in recursiveitasks:
+                    totaldeps.update(recursiveitasks[tid])
+                    for dep in recursiveitasks[tid]:
+                        if dep not in self.runtaskentries:
+                            continue
+                        totaldeps.update(self.runtaskentries[dep].depends)
+
+                deps = set()
+                for dep in totaldeps:
+                    if dep in cumulativedeps:
+                        deps.update(cumulativedeps[dep])
+
+                for t in deps:
+                    for taskname in tasknames:
+                        newtid = t + ":" + taskname
+                        if newtid == tid:
+                            continue
+                        if newtid in self.runtaskentries and newtid not in self.runtaskentries[tid].depends:
+                            extradeps += 1
+                            self.runtaskentries[tid].depends.add(newtid)
+
+                # Handle recursive tasks which depend upon other recursive tasks
+                deps = set()
+                for dep in self.runtaskentries[tid].depends.intersection(recursivetasks):
+                    deps.update(self.runtaskentries[dep].depends.difference(self.runtaskentries[tid].depends))
+                for newtid in deps:
+                    for taskname in tasknames:
+                        if not newtid.endswith(":" + taskname):
+                            continue
+                        if newtid in self.runtaskentries:
+                            extradeps += 1
+                            self.runtaskentries[tid].depends.add(newtid)
+
+            bb.debug(1, "Added %s recursive dependencies in this loop" % extradeps)
+
+        # Remove recrdeptask circular references so that do_a[recrdeptask] = "do_a do_b" can work
+        for tid in recursivetasksselfref:
+            self.runtaskentries[tid].depends.difference_update(recursivetasksselfref)
+
+        self.init_progress_reporter.next_stage()
+
+        #self.dump_data()
+
+        # Step B - Mark all active tasks
+        #
+        # Start with the tasks we were asked to run and mark all dependencies
+        # as active too. If the task is to be 'forced', clear its stamp. Once
+        # all active tasks are marked, prune the ones we don't need.
+
+        logger.verbose("Marking Active Tasks")
+
+        def mark_active(tid, depth):
+            """
+            Mark an item as active along with its depends
+            (calls itself recursively)
+            """
+
+            if tid in runq_build:
+                return
+
+            runq_build[tid] = 1
+
+            depends = self.runtaskentries[tid].depends
+            for depend in depends:
+                mark_active(depend, depth+1)
+
+        self.target_tids = []
+        for (mc, target, task, fn) in self.targets:
+
+            if target not in taskData[mc].build_targets or not taskData[mc].build_targets[target]:
+                continue
+
+            if target in taskData[mc].failed_deps:
+                continue
+
+            parents = False
+            if task.endswith('-'):
+                parents = True
+                task = task[:-1]
+
+            if fn in taskData[mc].failed_fns:
+                continue
+
+            # fn already has mc prefix
+            tid = fn + ":" + task
+            self.target_tids.append(tid)
+            if tid not in taskData[mc].taskentries:
+                import difflib
+                tasks = []
+                for x in taskData[mc].taskentries:
+                    if x.startswith(fn + ":"):
+                        tasks.append(taskname_from_tid(x))
+                close_matches = difflib.get_close_matches(task, tasks, cutoff=0.7)
+                if close_matches:
+                    extra = ". Close matches:\n  %s" % "\n  ".join(close_matches)
+                else:
+                    extra = ""
+                bb.msg.fatal("RunQueue", "Task %s does not exist for target %s (%s)%s" % (task, target, tid, extra))
+
+            # For tasks called "XXXX-", ony run their dependencies
+            if parents:
+                for i in self.runtaskentries[tid].depends:
+                    mark_active(i, 1)
+            else:
+                mark_active(tid, 1)
+
+        self.init_progress_reporter.next_stage()
+
+        # Step C - Prune all inactive tasks
+        #
+        # Once all active tasks are marked, prune the ones we don't need.
+
+        delcount = {}
+        for tid in list(self.runtaskentries.keys()):
+            if tid not in runq_build:
+                delcount[tid] = self.runtaskentries[tid]
+                del self.runtaskentries[tid]
+
+        # Handle --runall
+        if self.cooker.configuration.runall:
+            # re-run the mark_active and then drop unused tasks from new list
+            runq_build = {}
+
+            for task in self.cooker.configuration.runall:
+                runall_tids = set()
+                for tid in list(self.runtaskentries):
+                    wanttid = fn_from_tid(tid) + ":do_%s" % task
+                    if wanttid in delcount:
+                        self.runtaskentries[wanttid] = delcount[wanttid]
+                    if wanttid in self.runtaskentries:
+                        runall_tids.add(wanttid)
+
+                for tid in list(runall_tids):
+                    mark_active(tid,1)
+
+            for tid in list(self.runtaskentries.keys()):
+                if tid not in runq_build:
+                    delcount[tid] = self.runtaskentries[tid]
+                    del self.runtaskentries[tid]
+
+            if len(self.runtaskentries) == 0:
+                bb.msg.fatal("RunQueue", "Could not find any tasks with the tasknames %s to run within the recipes of the taskgraphs of the targets %s" % (str(self.cooker.configuration.runall), str(self.targets)))
+
+        self.init_progress_reporter.next_stage()
+
+        # Handle runonly
+        if self.cooker.configuration.runonly:
+            # re-run the mark_active and then drop unused tasks from new list
+            runq_build = {}
+
+            for task in self.cooker.configuration.runonly:
+                runonly_tids = { k: v for k, v in self.runtaskentries.items() if taskname_from_tid(k) == "do_%s" % task }
+
+                for tid in list(runonly_tids):
+                    mark_active(tid,1)
+
+            for tid in list(self.runtaskentries.keys()):
+                if tid not in runq_build:
+                    delcount[tid] = self.runtaskentries[tid]
+                    del self.runtaskentries[tid]
+
+            if len(self.runtaskentries) == 0:
+                bb.msg.fatal("RunQueue", "Could not find any tasks with the tasknames %s to run within the taskgraphs of the targets %s" % (str(self.cooker.configuration.runonly), str(self.targets)))
+
+        #
+        # Step D - Sanity checks and computation
+        #
+
+        # Check to make sure we still have tasks to run
+        if len(self.runtaskentries) == 0:
+            if not taskData[''].abort:
+                bb.msg.fatal("RunQueue", "All buildable tasks have been run but the build is incomplete (--continue mode). Errors for the tasks that failed will have been printed above.")
+            else:
+                bb.msg.fatal("RunQueue", "No active tasks and not in --continue mode?! Please report this bug.")
+
+        logger.verbose("Pruned %s inactive tasks, %s left", len(delcount), len(self.runtaskentries))
+
+        logger.verbose("Assign Weightings")
+
+        self.init_progress_reporter.next_stage()
+
+        # Generate a list of reverse dependencies to ease future calculations
+        for tid in self.runtaskentries:
+            for dep in self.runtaskentries[tid].depends:
+                self.runtaskentries[dep].revdeps.add(tid)
+
+        self.init_progress_reporter.next_stage()
+
+        # Identify tasks at the end of dependency chains
+        # Error on circular dependency loops (length two)
+        endpoints = []
+        for tid in self.runtaskentries:
+            revdeps = self.runtaskentries[tid].revdeps
+            if len(revdeps) == 0:
+                endpoints.append(tid)
+            for dep in revdeps:
+                if dep in self.runtaskentries[tid].depends:
+                    bb.msg.fatal("RunQueue", "Task %s has circular dependency on %s" % (tid, dep))
+
+
+        logger.verbose("Compute totals (have %s endpoint(s))", len(endpoints))
+
+        self.init_progress_reporter.next_stage()
+
+        # Calculate task weights
+        # Check of higher length circular dependencies
+        self.runq_weight = self.calculate_task_weights(endpoints)
+
+        self.init_progress_reporter.next_stage()
+
+        # Sanity Check - Check for multiple tasks building the same provider
+        for mc in self.dataCaches:
+            prov_list = {}
+            seen_fn = []
+            for tid in self.runtaskentries:
+                (tidmc, fn, taskname, taskfn) = split_tid_mcfn(tid)
+                if taskfn in seen_fn:
+                    continue
+                if mc != tidmc:
+                    continue
+                seen_fn.append(taskfn)
+                for prov in self.dataCaches[mc].fn_provides[taskfn]:
+                    if prov not in prov_list:
+                        prov_list[prov] = [taskfn]
+                    elif taskfn not in prov_list[prov]:
+                        prov_list[prov].append(taskfn)
+            for prov in prov_list:
+                if len(prov_list[prov]) < 2:
+                    continue
+                if prov in self.multi_provider_whitelist:
+                    continue
+                seen_pn = []
+                # If two versions of the same PN are being built its fatal, we don't support it.
+                for fn in prov_list[prov]:
+                    pn = self.dataCaches[mc].pkg_fn[fn]
+                    if pn not in seen_pn:
+                        seen_pn.append(pn)
+                    else:
+                        bb.fatal("Multiple versions of %s are due to be built (%s). Only one version of a given PN should be built in any given build. You likely need to set PREFERRED_VERSION_%s to select the correct version or don't depend on multiple versions." % (pn, " ".join(prov_list[prov]), pn))
+                msg = "Multiple .bb files are due to be built which each provide %s:\n  %s" % (prov, "\n  ".join(prov_list[prov]))
+                #
+                # Construct a list of things which uniquely depend on each provider
+                # since this may help the user figure out which dependency is triggering this warning
+                #
+                msg += "\nA list of tasks depending on these providers is shown and may help explain where the dependency comes from."
+                deplist = {}
+                commondeps = None
+                for provfn in prov_list[prov]:
+                    deps = set()
+                    for tid in self.runtaskentries:
+                        fn = fn_from_tid(tid)
+                        if fn != provfn:
+                            continue
+                        for dep in self.runtaskentries[tid].revdeps:
+                            fn = fn_from_tid(dep)
+                            if fn == provfn:
+                                continue
+                            deps.add(dep)
+                    if not commondeps:
+                        commondeps = set(deps)
+                    else:
+                        commondeps &= deps
+                    deplist[provfn] = deps
+                for provfn in deplist:
+                    msg += "\n%s has unique dependees:\n  %s" % (provfn, "\n  ".join(deplist[provfn] - commondeps))
+                #
+                # Construct a list of provides and runtime providers for each recipe
+                # (rprovides has to cover RPROVIDES, PACKAGES, PACKAGES_DYNAMIC)
+                #
+                msg += "\nIt could be that one recipe provides something the other doesn't and should. The following provider and runtime provider differences may be helpful."
+                provide_results = {}
+                rprovide_results = {}
+                commonprovs = None
+                commonrprovs = None
+                for provfn in prov_list[prov]:
+                    provides = set(self.dataCaches[mc].fn_provides[provfn])
+                    rprovides = set()
+                    for rprovide in self.dataCaches[mc].rproviders:
+                        if provfn in self.dataCaches[mc].rproviders[rprovide]:
+                            rprovides.add(rprovide)
+                    for package in self.dataCaches[mc].packages:
+                        if provfn in self.dataCaches[mc].packages[package]:
+                            rprovides.add(package)
+                    for package in self.dataCaches[mc].packages_dynamic:
+                        if provfn in self.dataCaches[mc].packages_dynamic[package]:
+                            rprovides.add(package)
+                    if not commonprovs:
+                        commonprovs = set(provides)
+                    else:
+                        commonprovs &= provides
+                    provide_results[provfn] = provides
+                    if not commonrprovs:
+                        commonrprovs = set(rprovides)
+                    else:
+                        commonrprovs &= rprovides
+                    rprovide_results[provfn] = rprovides
+                #msg += "\nCommon provides:\n  %s" % ("\n  ".join(commonprovs))
+                #msg += "\nCommon rprovides:\n  %s" % ("\n  ".join(commonrprovs))
+                for provfn in prov_list[prov]:
+                    msg += "\n%s has unique provides:\n  %s" % (provfn, "\n  ".join(provide_results[provfn] - commonprovs))
+                    msg += "\n%s has unique rprovides:\n  %s" % (provfn, "\n  ".join(rprovide_results[provfn] - commonrprovs))
+
+                if self.warn_multi_bb:
+                    logger.verbnote(msg)
+                else:
+                    logger.error(msg)
+
+        self.init_progress_reporter.next_stage()
+
+        # Create a whitelist usable by the stamp checks
+        self.stampfnwhitelist = {}
+        for mc in self.taskData:
+            self.stampfnwhitelist[mc] = []
+            for entry in self.stampwhitelist.split():
+                if entry not in self.taskData[mc].build_targets:
+                    continue
+                fn = self.taskData.build_targets[entry][0]
+                self.stampfnwhitelist[mc].append(fn)
+
+        self.init_progress_reporter.next_stage()
+
+        # Iterate over the task list looking for tasks with a 'setscene' function
+        self.runq_setscene_tids = []
+        if not self.cooker.configuration.nosetscene:
+            for tid in self.runtaskentries:
+                (mc, fn, taskname, _) = split_tid_mcfn(tid)
+                setscenetid = tid + "_setscene"
+                if setscenetid not in taskData[mc].taskentries:
+                    continue
+                self.runq_setscene_tids.append(tid)
+
+        def invalidate_task(tid, error_nostamp):
+            (mc, fn, taskname, taskfn) = split_tid_mcfn(tid)
+            taskdep = self.dataCaches[mc].task_deps[taskfn]
+            if fn + ":" + taskname not in taskData[mc].taskentries:
+                logger.warning("Task %s does not exist, invalidating this task will have no effect" % taskname)
+            if 'nostamp' in taskdep and taskname in taskdep['nostamp']:
+                if error_nostamp:
+                    bb.fatal("Task %s is marked nostamp, cannot invalidate this task" % taskname)
+                else:
+                    bb.debug(1, "Task %s is marked nostamp, cannot invalidate this task" % taskname)
+            else:
+                logger.verbose("Invalidate task %s, %s", taskname, fn)
+                bb.parse.siggen.invalidate_task(taskname, self.dataCaches[mc], taskfn)
+
+        self.init_progress_reporter.next_stage()
+
+        # Invalidate task if force mode active
+        if self.cooker.configuration.force:
+            for tid in self.target_tids:
+                invalidate_task(tid, False)
+
+        # Invalidate task if invalidate mode active
+        if self.cooker.configuration.invalidate_stamp:
+            for tid in self.target_tids:
+                fn = fn_from_tid(tid)
+                for st in self.cooker.configuration.invalidate_stamp.split(','):
+                    if not st.startswith("do_"):
+                        st = "do_%s" % st
+                    invalidate_task(fn + ":" + st, True)
+
+        self.init_progress_reporter.next_stage()
+
+        # Create and print to the logs a virtual/xxxx -> PN (fn) table
+        for mc in taskData:
+            virtmap = taskData[mc].get_providermap(prefix="virtual/")
+            virtpnmap = {}
+            for v in virtmap:
+                virtpnmap[v] = self.dataCaches[mc].pkg_fn[virtmap[v]]
+                bb.debug(2, "%s resolved to: %s (%s)" % (v, virtpnmap[v], virtmap[v]))
+            if hasattr(bb.parse.siggen, "tasks_resolved"):
+                bb.parse.siggen.tasks_resolved(virtmap, virtpnmap, self.dataCaches[mc])
+
+        self.init_progress_reporter.next_stage()
+
+        # Iterate over the task list and call into the siggen code
+        dealtwith = set()
+        todeal = set(self.runtaskentries)
+        while len(todeal) > 0:
+            for tid in todeal.copy():
+                if len(self.runtaskentries[tid].depends - dealtwith) == 0:
+                    dealtwith.add(tid)
+                    todeal.remove(tid)
+                    procdep = []
+                    for dep in self.runtaskentries[tid].depends:
+                        procdep.append(fn_from_tid(dep) + "." + taskname_from_tid(dep))
+                    (mc, fn, taskname, taskfn) = split_tid_mcfn(tid)
+                    self.runtaskentries[tid].hash = bb.parse.siggen.get_taskhash(taskfn, taskname, procdep, self.dataCaches[mc])
+                    task = self.runtaskentries[tid].task
+
+        bb.parse.siggen.writeout_file_checksum_cache()
+
+        #self.dump_data()
+        return len(self.runtaskentries)
+
+    def dump_data(self):
+        """
+        Dump some debug information on the internal data structures
+        """
+        logger.debug(3, "run_tasks:")
+        for tid in self.runtaskentries:
+            logger.debug(3, " %s: %s   Deps %s RevDeps %s", tid,
+                         self.runtaskentries[tid].weight,
+                         self.runtaskentries[tid].depends,
+                         self.runtaskentries[tid].revdeps)
+
+class RunQueueWorker():
+    def __init__(self, process, pipe):
+        self.process = process
+        self.pipe = pipe
+
+class RunQueue:
+    def __init__(self, cooker, cfgData, dataCaches, taskData, targets):
+
+        self.cooker = cooker
+        self.cfgData = cfgData
+        self.rqdata = RunQueueData(self, cooker, cfgData, dataCaches, taskData, targets)
+
+        self.stamppolicy = cfgData.getVar("BB_STAMP_POLICY") or "perfile"
+        self.hashvalidate = cfgData.getVar("BB_HASHCHECK_FUNCTION") or None
+        self.setsceneverify = cfgData.getVar("BB_SETSCENE_VERIFY_FUNCTION2") or None
+        self.depvalidate = cfgData.getVar("BB_SETSCENE_DEPVALID") or None
+
+        self.state = runQueuePrepare
+
+        # For disk space monitor
+        # Invoked at regular time intervals via the bitbake heartbeat event
+        # while the build is running. We generate a unique name for the handler
+        # here, just in case that there ever is more than one RunQueue instance,
+        # start the handler when reaching runQueueSceneRun, and stop it when
+        # done with the build.
+        self.dm = monitordisk.diskMonitor(cfgData)
+        self.dm_event_handler_name = '_bb_diskmonitor_' + str(id(self))
+        self.dm_event_handler_registered = False
+        self.rqexe = None
+        self.worker = {}
+        self.fakeworker = {}
+
+    def _start_worker(self, mc, fakeroot = False, rqexec = None):
+        logger.debug(1, "Starting bitbake-worker")
+        magic = "decafbad"
+        if self.cooker.configuration.profile:
+            magic = "decafbadbad"
+        if fakeroot:
+            magic = magic + "beef"
+            mcdata = self.cooker.databuilder.mcdata[mc]
+            fakerootcmd = mcdata.getVar("FAKEROOTCMD")
+            fakerootenv = (mcdata.getVar("FAKEROOTBASEENV") or "").split()
+            env = os.environ.copy()
+            for key, value in (var.split('=') for var in fakerootenv):
+                env[key] = value
+            worker = subprocess.Popen([fakerootcmd, "bitbake-worker", magic], stdout=subprocess.PIPE, stdin=subprocess.PIPE, env=env)
+        else:
+            worker = subprocess.Popen(["bitbake-worker", magic], stdout=subprocess.PIPE, stdin=subprocess.PIPE)
+        bb.utils.nonblockingfd(worker.stdout)
+        workerpipe = runQueuePipe(worker.stdout, None, self.cfgData, self, rqexec)
+
+        runqhash = {}
+        for tid in self.rqdata.runtaskentries:
+            runqhash[tid] = self.rqdata.runtaskentries[tid].hash
+
+        workerdata = {
+            "taskdeps" : self.rqdata.dataCaches[mc].task_deps,
+            "fakerootenv" : self.rqdata.dataCaches[mc].fakerootenv,
+            "fakerootdirs" : self.rqdata.dataCaches[mc].fakerootdirs,
+            "fakerootnoenv" : self.rqdata.dataCaches[mc].fakerootnoenv,
+            "sigdata" : bb.parse.siggen.get_taskdata(),
+            "runq_hash" : runqhash,
+            "logdefaultdebug" : bb.msg.loggerDefaultDebugLevel,
+            "logdefaultverbose" : bb.msg.loggerDefaultVerbose,
+            "logdefaultverboselogs" : bb.msg.loggerVerboseLogs,
+            "logdefaultdomain" : bb.msg.loggerDefaultDomains,
+            "prhost" : self.cooker.prhost,
+            "buildname" : self.cfgData.getVar("BUILDNAME"),
+            "date" : self.cfgData.getVar("DATE"),
+            "time" : self.cfgData.getVar("TIME"),
+        }
+
+        worker.stdin.write(b"<cookerconfig>" + pickle.dumps(self.cooker.configuration) + b"</cookerconfig>")
+        worker.stdin.write(b"<extraconfigdata>" + pickle.dumps(self.cooker.extraconfigdata) + b"</extraconfigdata>")
+        worker.stdin.write(b"<workerdata>" + pickle.dumps(workerdata) + b"</workerdata>")
+        worker.stdin.flush()
+
+        return RunQueueWorker(worker, workerpipe)
+
+    def _teardown_worker(self, worker):
+        if not worker:
+            return
+        logger.debug(1, "Teardown for bitbake-worker")
+        try:
+           worker.process.stdin.write(b"<quit></quit>")
+           worker.process.stdin.flush()
+           worker.process.stdin.close()
+        except IOError:
+           pass
+        while worker.process.returncode is None:
+            worker.pipe.read()
+            worker.process.poll()
+        while worker.pipe.read():
+            continue
+        worker.pipe.close()
+
+    def start_worker(self):
+        if self.worker:
+            self.teardown_workers()
+        self.teardown = False
+        for mc in self.rqdata.dataCaches:
+            self.worker[mc] = self._start_worker(mc)
+
+    def start_fakeworker(self, rqexec, mc):
+        if not mc in self.fakeworker:
+            self.fakeworker[mc] = self._start_worker(mc, True, rqexec)
+
+    def teardown_workers(self):
+        self.teardown = True
+        for mc in self.worker:
+            self._teardown_worker(self.worker[mc])
+        self.worker = {}
+        for mc in self.fakeworker:
+            self._teardown_worker(self.fakeworker[mc])
+        self.fakeworker = {}
+
+    def read_workers(self):
+        for mc in self.worker:
+            self.worker[mc].pipe.read()
+        for mc in self.fakeworker:
+            self.fakeworker[mc].pipe.read()
+
+    def active_fds(self):
+        fds = []
+        for mc in self.worker:
+            fds.append(self.worker[mc].pipe.input)
+        for mc in self.fakeworker:
+            fds.append(self.fakeworker[mc].pipe.input)
+        return fds
+
+    def check_stamp_task(self, tid, taskname = None, recurse = False, cache = None):
+        def get_timestamp(f):
+            try:
+                if not os.access(f, os.F_OK):
+                    return None
+                return os.stat(f)[stat.ST_MTIME]
+            except:
+                return None
+
+        (mc, fn, tn, taskfn) = split_tid_mcfn(tid)
+        if taskname is None:
+            taskname = tn
+
+        if self.stamppolicy == "perfile":
+            fulldeptree = False
+        else:
+            fulldeptree = True
+            stampwhitelist = []
+            if self.stamppolicy == "whitelist":
+                stampwhitelist = self.rqdata.stampfnwhitelist[mc]
+
+        stampfile = bb.build.stampfile(taskname, self.rqdata.dataCaches[mc], taskfn)
+
+        # If the stamp is missing, it's not current
+        if not os.access(stampfile, os.F_OK):
+            logger.debug(2, "Stampfile %s not available", stampfile)
+            return False
+        # If it's a 'nostamp' task, it's not current
+        taskdep = self.rqdata.dataCaches[mc].task_deps[taskfn]
+        if 'nostamp' in taskdep and taskname in taskdep['nostamp']:
+            logger.debug(2, "%s.%s is nostamp\n", fn, taskname)
+            return False
+
+        if taskname != "do_setscene" and taskname.endswith("_setscene"):
+            return True
+
+        if cache is None:
+            cache = {}
+
+        iscurrent = True
+        t1 = get_timestamp(stampfile)
+        for dep in self.rqdata.runtaskentries[tid].depends:
+            if iscurrent:
+                (mc2, fn2, taskname2, taskfn2) = split_tid_mcfn(dep)
+                stampfile2 = bb.build.stampfile(taskname2, self.rqdata.dataCaches[mc2], taskfn2)
+                stampfile3 = bb.build.stampfile(taskname2 + "_setscene", self.rqdata.dataCaches[mc2], taskfn2)
+                t2 = get_timestamp(stampfile2)
+                t3 = get_timestamp(stampfile3)
+                if t3 and not t2:
+                    continue
+                if t3 and t3 > t2:
+                    continue
+                if fn == fn2 or (fulldeptree and fn2 not in stampwhitelist):
+                    if not t2:
+                        logger.debug(2, 'Stampfile %s does not exist', stampfile2)
+                        iscurrent = False
+                        break
+                    if t1 < t2:
+                        logger.debug(2, 'Stampfile %s < %s', stampfile, stampfile2)
+                        iscurrent = False
+                        break
+                    if recurse and iscurrent:
+                        if dep in cache:
+                            iscurrent = cache[dep]
+                            if not iscurrent:
+                                logger.debug(2, 'Stampfile for dependency %s:%s invalid (cached)' % (fn2, taskname2))
+                        else:
+                            iscurrent = self.check_stamp_task(dep, recurse=True, cache=cache)
+                            cache[dep] = iscurrent
+        if recurse:
+            cache[tid] = iscurrent
+        return iscurrent
+
+    def _execute_runqueue(self):
+        """
+        Run the tasks in a queue prepared by rqdata.prepare()
+        Upon failure, optionally try to recover the build using any alternate providers
+        (if the abort on failure configuration option isn't set)
+        """
+
+        retval = True
+
+        if self.state is runQueuePrepare:
+            self.rqexe = RunQueueExecuteDummy(self)
+            # NOTE: if you add, remove or significantly refactor the stages of this
+            # process then you should recalculate the weightings here. This is quite
+            # easy to do - just change the next line temporarily to pass debug=True as
+            # the last parameter and you'll get a printout of the weightings as well
+            # as a map to the lines where next_stage() was called. Of course this isn't
+            # critical, but it helps to keep the progress reporting accurate.
+            self.rqdata.init_progress_reporter = bb.progress.MultiStageProcessProgressReporter(self.cooker.data,
+                                                            "Initialising tasks",
+                                                            [43, 967, 4, 3, 1, 5, 3, 7, 13, 1, 2, 1, 1, 246, 35, 1, 38, 1, 35, 2, 338, 204, 142, 3, 3, 37, 244])
+            if self.rqdata.prepare() == 0:
+                self.state = runQueueComplete
+            else:
+                self.state = runQueueSceneInit
+                self.rqdata.init_progress_reporter.next_stage()
+
+                # we are ready to run,  emit dependency info to any UI or class which
+                # needs it
+                depgraph = self.cooker.buildDependTree(self, self.rqdata.taskData)
+                self.rqdata.init_progress_reporter.next_stage()
+                bb.event.fire(bb.event.DepTreeGenerated(depgraph), self.cooker.data)
+
+        if self.state is runQueueSceneInit:
+            if not self.dm_event_handler_registered:
+                 res = bb.event.register(self.dm_event_handler_name,
+                                         lambda x: self.dm.check(self) if self.state in [runQueueSceneRun, runQueueRunning, runQueueCleanUp] else False,
+                                         ('bb.event.HeartbeatEvent',))
+                 self.dm_event_handler_registered = True
+
+            dump = self.cooker.configuration.dump_signatures
+            if dump:
+                self.rqdata.init_progress_reporter.finish()
+                if 'printdiff' in dump:
+                    invalidtasks = self.print_diffscenetasks()
+                self.dump_signatures(dump)
+                if 'printdiff' in dump:
+                    self.write_diffscenetasks(invalidtasks)
+                self.state = runQueueComplete
+            else:
+                self.rqdata.init_progress_reporter.next_stage()
+                self.start_worker()
+                self.rqdata.init_progress_reporter.next_stage()
+                self.rqexe = RunQueueExecuteScenequeue(self)
+
+        if self.state is runQueueSceneRun:
+            retval = self.rqexe.execute()
+
+        if self.state is runQueueRunInit:
+            if self.cooker.configuration.setsceneonly:
+                self.state = runQueueComplete
+            else:
+                # Just in case we didn't setscene
+                self.rqdata.init_progress_reporter.finish()
+                logger.info("Executing RunQueue Tasks")
+                self.rqexe = RunQueueExecuteTasks(self)
+                self.state = runQueueRunning
+
+        if self.state is runQueueRunning:
+            retval = self.rqexe.execute()
+
+        if self.state is runQueueCleanUp:
+            retval = self.rqexe.finish()
+
+        build_done = self.state is runQueueComplete or self.state is runQueueFailed
+
+        if build_done and self.dm_event_handler_registered:
+            bb.event.remove(self.dm_event_handler_name, None)
+            self.dm_event_handler_registered = False
+
+        if build_done and self.rqexe:
+            self.teardown_workers()
+            if self.rqexe.stats.failed:
+                logger.info("Tasks Summary: Attempted %d tasks of which %d didn't need to be rerun and %d failed.", self.rqexe.stats.completed + self.rqexe.stats.failed, self.rqexe.stats.skipped, self.rqexe.stats.failed)
+            else:
+                # Let's avoid the word "failed" if nothing actually did
+                logger.info("Tasks Summary: Attempted %d tasks of which %d didn't need to be rerun and all succeeded.", self.rqexe.stats.completed, self.rqexe.stats.skipped)
+
+        if self.state is runQueueFailed:
+            raise bb.runqueue.TaskFailure(self.rqexe.failed_tids)
+
+        if self.state is runQueueComplete:
+            # All done
+            return False
+
+        # Loop
+        return retval
+
+    def execute_runqueue(self):
+        # Catch unexpected exceptions and ensure we exit when an error occurs, not loop.
+        try:
+            return self._execute_runqueue()
+        except bb.runqueue.TaskFailure:
+            raise
+        except SystemExit:
+            raise
+        except bb.BBHandledException:
+            try:
+                self.teardown_workers()
+            except:
+                pass
+            self.state = runQueueComplete
+            raise
+        except Exception as err:
+            logger.exception("An uncaught exception occurred in runqueue")
+            try:
+                self.teardown_workers()
+            except:
+                pass
+            self.state = runQueueComplete
+            raise
+
+    def finish_runqueue(self, now = False):
+        if not self.rqexe:
+            self.state = runQueueComplete
+            return
+
+        if now:
+            self.rqexe.finish_now()
+        else:
+            self.rqexe.finish()
+
+    def rq_dump_sigfn(self, fn, options):
+        bb_cache = bb.cache.NoCache(self.cooker.databuilder)
+        the_data = bb_cache.loadDataFull(fn, self.cooker.collection.get_file_appends(fn))
+        siggen = bb.parse.siggen
+        dataCaches = self.rqdata.dataCaches
+        siggen.dump_sigfn(fn, dataCaches, options)
+
+    def dump_signatures(self, options):
+        fns = set()
+        bb.note("Reparsing files to collect dependency data")
+
+        for tid in self.rqdata.runtaskentries:
+            fn = fn_from_tid(tid)
+            fns.add(fn)
+
+        max_process = int(self.cfgData.getVar("BB_NUMBER_PARSE_THREADS") or os.cpu_count() or 1)
+        # We cannot use the real multiprocessing.Pool easily due to some local data
+        # that can't be pickled. This is a cheap multi-process solution.
+        launched = []
+        while fns:
+            if len(launched) < max_process:
+                p = Process(target=self.rq_dump_sigfn, args=(fns.pop(), options))
+                p.start()
+                launched.append(p)
+            for q in launched:
+                # The finished processes are joined when calling is_alive()
+                if not q.is_alive():
+                    launched.remove(q)
+        for p in launched:
+                p.join()
+
+        bb.parse.siggen.dump_sigs(self.rqdata.dataCaches, options)
+
+        return
+
+    def print_diffscenetasks(self):
+
+        valid = []
+        sq_hash = []
+        sq_hashfn = []
+        sq_fn = []
+        sq_taskname = []
+        sq_task = []
+        noexec = []
+        stamppresent = []
+        valid_new = set()
+
+        for tid in self.rqdata.runtaskentries:
+            (mc, fn, taskname, taskfn) = split_tid_mcfn(tid)
+            taskdep = self.rqdata.dataCaches[mc].task_deps[taskfn]
+
+            if 'noexec' in taskdep and taskname in taskdep['noexec']:
+                noexec.append(tid)
+                continue
+
+            sq_fn.append(fn)
+            sq_hashfn.append(self.rqdata.dataCaches[mc].hashfn[taskfn])
+            sq_hash.append(self.rqdata.runtaskentries[tid].hash)
+            sq_taskname.append(taskname)
+            sq_task.append(tid)
+        locs = { "sq_fn" : sq_fn, "sq_task" : sq_taskname, "sq_hash" : sq_hash, "sq_hashfn" : sq_hashfn, "d" : self.cooker.data }
+        try:
+            call = self.hashvalidate + "(sq_fn, sq_task, sq_hash, sq_hashfn, d, siginfo=True)"
+            valid = bb.utils.better_eval(call, locs)
+        # Handle version with no siginfo parameter
+        except TypeError:
+            call = self.hashvalidate + "(sq_fn, sq_task, sq_hash, sq_hashfn, d)"
+            valid = bb.utils.better_eval(call, locs)
+        for v in valid:
+            valid_new.add(sq_task[v])
+
+        # Tasks which are both setscene and noexec never care about dependencies
+        # We therefore find tasks which are setscene and noexec and mark their
+        # unique dependencies as valid.
+        for tid in noexec:
+            if tid not in self.rqdata.runq_setscene_tids:
+                continue
+            for dep in self.rqdata.runtaskentries[tid].depends:
+                hasnoexecparents = True
+                for dep2 in self.rqdata.runtaskentries[dep].revdeps:
+                    if dep2 in self.rqdata.runq_setscene_tids and dep2 in noexec:
+                        continue
+                    hasnoexecparents = False
+                    break
+                if hasnoexecparents:
+                    valid_new.add(dep)
+
+        invalidtasks = set()
+        for tid in self.rqdata.runtaskentries:
+            if tid not in valid_new and tid not in noexec:
+                invalidtasks.add(tid)
+
+        found = set()
+        processed = set()
+        for tid in invalidtasks:
+            toprocess = set([tid])
+            while toprocess:
+                next = set()
+                for t in toprocess:
+                    for dep in self.rqdata.runtaskentries[t].depends:
+                        if dep in invalidtasks:
+                            found.add(tid)
+                        if dep not in processed:
+                            processed.add(dep)
+                            next.add(dep)
+                toprocess = next
+                if tid in found:
+                    toprocess = set()
+
+        tasklist = []
+        for tid in invalidtasks.difference(found):
+            tasklist.append(tid)
+
+        if tasklist:
+            bb.plain("The differences between the current build and any cached tasks start at the following tasks:\n" + "\n".join(tasklist))
+
+        return invalidtasks.difference(found)
+
+    def write_diffscenetasks(self, invalidtasks):
+
+        # Define recursion callback
+        def recursecb(key, hash1, hash2):
+            hashes = [hash1, hash2]
+            hashfiles = bb.siggen.find_siginfo(key, None, hashes, self.cfgData)
+
+            recout = []
+            if len(hashfiles) == 2:
+                out2 = bb.siggen.compare_sigfiles(hashfiles[hash1], hashfiles[hash2], recursecb)
+                recout.extend(list('  ' + l for l in out2))
+            else:
+                recout.append("Unable to find matching sigdata for %s with hashes %s or %s" % (key, hash1, hash2))
+
+            return recout
+
+
+        for tid in invalidtasks:
+            (mc, fn, taskname, taskfn) = split_tid_mcfn(tid)
+            pn = self.rqdata.dataCaches[mc].pkg_fn[taskfn]
+            h = self.rqdata.runtaskentries[tid].hash
+            matches = bb.siggen.find_siginfo(pn, taskname, [], self.cfgData)
+            match = None
+            for m in matches:
+                if h in m:
+                    match = m
+            if match is None:
+                bb.fatal("Can't find a task we're supposed to have written out? (hash: %s)?" % h)
+            matches = {k : v for k, v in iter(matches.items()) if h not in k}
+            if matches:
+                latestmatch = sorted(matches.keys(), key=lambda f: matches[f])[-1]
+                prevh = __find_md5__.search(latestmatch).group(0)
+                output = bb.siggen.compare_sigfiles(latestmatch, match, recursecb)
+                bb.plain("\nTask %s:%s couldn't be used from the cache because:\n  We need hash %s, closest matching task was %s\n  " % (pn, taskname, h, prevh) + '\n  '.join(output))
+
+class RunQueueExecute:
+
+    def __init__(self, rq):
+        self.rq = rq
+        self.cooker = rq.cooker
+        self.cfgData = rq.cfgData
+        self.rqdata = rq.rqdata
+
+        self.number_tasks = int(self.cfgData.getVar("BB_NUMBER_THREADS") or 1)
+        self.scheduler = self.cfgData.getVar("BB_SCHEDULER") or "speed"
+
+        self.runq_buildable = set()
+        self.runq_running = set()
+        self.runq_complete = set()
+
+        self.build_stamps = {}
+        self.build_stamps2 = []
+        self.failed_tids = []
+
+        self.stampcache = {}
+
+        for mc in rq.worker:
+            rq.worker[mc].pipe.setrunqueueexec(self)
+        for mc in rq.fakeworker:
+            rq.fakeworker[mc].pipe.setrunqueueexec(self)
+
+        if self.number_tasks <= 0:
+             bb.fatal("Invalid BB_NUMBER_THREADS %s" % self.number_tasks)
+
+    def runqueue_process_waitpid(self, task, status):
+
+        # self.build_stamps[pid] may not exist when use shared work directory.
+        if task in self.build_stamps:
+            self.build_stamps2.remove(self.build_stamps[task])
+            del self.build_stamps[task]
+
+        if status != 0:
+            self.task_fail(task, status)
+        else:
+            self.task_complete(task)
+        return True
+
+    def finish_now(self):
+        for mc in self.rq.worker:
+            try:
+                self.rq.worker[mc].process.stdin.write(b"<finishnow></finishnow>")
+                self.rq.worker[mc].process.stdin.flush()
+            except IOError:
+                # worker must have died?
+                pass
+        for mc in self.rq.fakeworker:
+            try:
+                self.rq.fakeworker[mc].process.stdin.write(b"<finishnow></finishnow>")
+                self.rq.fakeworker[mc].process.stdin.flush()
+            except IOError:
+                # worker must have died?
+                pass
+
+        if len(self.failed_tids) != 0:
+            self.rq.state = runQueueFailed
+            return
+
+        self.rq.state = runQueueComplete
+        return
+
+    def finish(self):
+        self.rq.state = runQueueCleanUp
+
+        if self.stats.active > 0:
+            bb.event.fire(runQueueExitWait(self.stats.active), self.cfgData)
+            self.rq.read_workers()
+            return self.rq.active_fds()
+
+        if len(self.failed_tids) != 0:
+            self.rq.state = runQueueFailed
+            return True
+
+        self.rq.state = runQueueComplete
+        return True
+
+    def check_dependencies(self, task, taskdeps, setscene = False):
+        if not self.rq.depvalidate:
+            return False
+
+        taskdata = {}
+        taskdeps.add(task)
+        for dep in taskdeps:
+            (mc, fn, taskname, taskfn) = split_tid_mcfn(dep)
+            pn = self.rqdata.dataCaches[mc].pkg_fn[taskfn]
+            taskdata[dep] = [pn, taskname, fn]
+        call = self.rq.depvalidate + "(task, taskdata, notneeded, d)"
+        locs = { "task" : task, "taskdata" : taskdata, "notneeded" : self.scenequeue_notneeded, "d" : self.cooker.data }
+        valid = bb.utils.better_eval(call, locs)
+        return valid
+
+    def can_start_task(self):
+        can_start = self.stats.active < self.number_tasks
+        return can_start
+
+class RunQueueExecuteDummy(RunQueueExecute):
+    def __init__(self, rq):
+        self.rq = rq
+        self.stats = RunQueueStats(0)
+
+    def finish(self):
+        self.rq.state = runQueueComplete
+        return
+
+class RunQueueExecuteTasks(RunQueueExecute):
+    def __init__(self, rq):
+        RunQueueExecute.__init__(self, rq)
+
+        self.stats = RunQueueStats(len(self.rqdata.runtaskentries))
+
+        self.stampcache = {}
+
+        initial_covered = self.rq.scenequeue_covered.copy()
+
+        # Mark initial buildable tasks
+        for tid in self.rqdata.runtaskentries:
+            if len(self.rqdata.runtaskentries[tid].depends) == 0:
+                self.runq_buildable.add(tid)
+            if len(self.rqdata.runtaskentries[tid].revdeps) > 0 and self.rqdata.runtaskentries[tid].revdeps.issubset(self.rq.scenequeue_covered):
+                self.rq.scenequeue_covered.add(tid)
+
+        found = True
+        while found:
+            found = False
+            for tid in self.rqdata.runtaskentries:
+                if tid in self.rq.scenequeue_covered:
+                    continue
+                logger.debug(1, 'Considering %s: %s' % (tid, str(self.rqdata.runtaskentries[tid].revdeps)))
+
+                if len(self.rqdata.runtaskentries[tid].revdeps) > 0 and self.rqdata.runtaskentries[tid].revdeps.issubset(self.rq.scenequeue_covered):
+                    if tid in self.rq.scenequeue_notcovered:
+                        continue
+                    found = True
+                    self.rq.scenequeue_covered.add(tid)
+
+        logger.debug(1, 'Skip list (pre setsceneverify) %s', sorted(self.rq.scenequeue_covered))
+
+        # Allow the metadata to elect for setscene tasks to run anyway
+        covered_remove = set()
+        if self.rq.setsceneverify:
+            invalidtasks = []
+            tasknames = {}
+            fns = {}
+            for tid in self.rqdata.runtaskentries:
+                (mc, fn, taskname, taskfn) = split_tid_mcfn(tid)
+                taskdep = self.rqdata.dataCaches[mc].task_deps[taskfn]
+                fns[tid] = taskfn
+                tasknames[tid] = taskname
+                if 'noexec' in taskdep and taskname in taskdep['noexec']:
+                    continue
+                if self.rq.check_stamp_task(tid, taskname + "_setscene", cache=self.stampcache):
+                    logger.debug(2, 'Setscene stamp current for task %s', tid)
+                    continue
+                if self.rq.check_stamp_task(tid, taskname, recurse = True, cache=self.stampcache):
+                    logger.debug(2, 'Normal stamp current for task %s', tid)
+                    continue
+                invalidtasks.append(tid)
+
+            call = self.rq.setsceneverify + "(covered, tasknames, fns, d, invalidtasks=invalidtasks)"
+            locs = { "covered" : self.rq.scenequeue_covered, "tasknames" : tasknames, "fns" : fns, "d" : self.cooker.data, "invalidtasks" : invalidtasks }
+            covered_remove = bb.utils.better_eval(call, locs)
+
+        def removecoveredtask(tid):
+            (mc, fn, taskname, taskfn) = split_tid_mcfn(tid)
+            taskname = taskname + '_setscene'
+            bb.build.del_stamp(taskname, self.rqdata.dataCaches[mc], taskfn)
+            self.rq.scenequeue_covered.remove(tid)
+
+        toremove = covered_remove | self.rq.scenequeue_notcovered
+        for task in toremove:
+            logger.debug(1, 'Not skipping task %s due to setsceneverify', task)
+        while toremove:
+            covered_remove = []
+            for task in toremove:
+                if task in self.rq.scenequeue_covered:
+                    removecoveredtask(task)
+                for deptask in self.rqdata.runtaskentries[task].depends:
+                    if deptask not in self.rq.scenequeue_covered:
+                        continue
+                    if deptask in toremove or deptask in covered_remove or deptask in initial_covered:
+                        continue
+                    logger.debug(1, 'Task %s depends on task %s so not skipping' % (task, deptask))
+                    covered_remove.append(deptask)
+            toremove = covered_remove
+
+        logger.debug(1, 'Full skip list %s', self.rq.scenequeue_covered)
+
+
+        for mc in self.rqdata.dataCaches:
+            target_pairs = []
+            for tid in self.rqdata.target_tids:
+                (tidmc, fn, taskname, _) = split_tid_mcfn(tid)
+                if tidmc == mc:
+                    target_pairs.append((fn, taskname))
+
+            event.fire(bb.event.StampUpdate(target_pairs, self.rqdata.dataCaches[mc].stamp), self.cfgData)
+
+        schedulers = self.get_schedulers()
+        for scheduler in schedulers:
+            if self.scheduler == scheduler.name:
+                self.sched = scheduler(self, self.rqdata)
+                logger.debug(1, "Using runqueue scheduler '%s'", scheduler.name)
+                break
+        else:
+            bb.fatal("Invalid scheduler '%s'.  Available schedulers: %s" %
+                     (self.scheduler, ", ".join(obj.name for obj in schedulers)))
+
+    def get_schedulers(self):
+        schedulers = set(obj for obj in globals().values()
+                             if type(obj) is type and
+                                issubclass(obj, RunQueueScheduler))
+
+        user_schedulers = self.cfgData.getVar("BB_SCHEDULERS")
+        if user_schedulers:
+            for sched in user_schedulers.split():
+                if not "." in sched:
+                    bb.note("Ignoring scheduler '%s' from BB_SCHEDULERS: not an import" % sched)
+                    continue
+
+                modname, name = sched.rsplit(".", 1)
+                try:
+                    module = __import__(modname, fromlist=(name,))
+                except ImportError as exc:
+                    logger.critical("Unable to import scheduler '%s' from '%s': %s" % (name, modname, exc))
+                    raise SystemExit(1)
+                else:
+                    schedulers.add(getattr(module, name))
+        return schedulers
+
+    def setbuildable(self, task):
+        self.runq_buildable.add(task)
+        self.sched.newbuildable(task)
+
+    def task_completeoutright(self, task):
+        """
+        Mark a task as completed
+        Look at the reverse dependencies and mark any task with
+        completed dependencies as buildable
+        """
+        self.runq_complete.add(task)
+        for revdep in self.rqdata.runtaskentries[task].revdeps:
+            if revdep in self.runq_running:
+                continue
+            if revdep in self.runq_buildable:
+                continue
+            alldeps = True
+            for dep in self.rqdata.runtaskentries[revdep].depends:
+                if dep not in self.runq_complete:
+                    alldeps = False
+                    break
+            if alldeps:
+                self.setbuildable(revdep)
+                logger.debug(1, "Marking task %s as buildable", revdep)
+
+    def task_complete(self, task):
+        self.stats.taskCompleted()
+        bb.event.fire(runQueueTaskCompleted(task, self.stats, self.rq), self.cfgData)
+        self.task_completeoutright(task)
+
+    def task_fail(self, task, exitcode):
+        """
+        Called when a task has failed
+        Updates the state engine with the failure
+        """
+        self.stats.taskFailed()
+        self.failed_tids.append(task)
+        bb.event.fire(runQueueTaskFailed(task, self.stats, exitcode, self.rq), self.cfgData)
+        if self.rqdata.taskData[''].abort:
+            self.rq.state = runQueueCleanUp
+
+    def task_skip(self, task, reason):
+        self.runq_running.add(task)
+        self.setbuildable(task)
+        bb.event.fire(runQueueTaskSkipped(task, self.stats, self.rq, reason), self.cfgData)
+        self.task_completeoutright(task)
+        self.stats.taskSkipped()
+        self.stats.taskCompleted()
+
+    def execute(self):
+        """
+        Run the tasks in a queue prepared by rqdata.prepare()
+        """
+
+        if self.rqdata.setscenewhitelist is not None and not self.rqdata.setscenewhitelist_checked:
+            self.rqdata.setscenewhitelist_checked = True
+
+            # Check tasks that are going to run against the whitelist
+            def check_norun_task(tid, showerror=False):
+                (mc, fn, taskname, taskfn) = split_tid_mcfn(tid)
+                # Ignore covered tasks
+                if tid in self.rq.scenequeue_covered:
+                    return False
+                # Ignore stamped tasks
+                if self.rq.check_stamp_task(tid, taskname, cache=self.stampcache):
+                    return False
+                # Ignore noexec tasks
+                taskdep = self.rqdata.dataCaches[mc].task_deps[taskfn]
+                if 'noexec' in taskdep and taskname in taskdep['noexec']:
+                    return False
+
+                pn = self.rqdata.dataCaches[mc].pkg_fn[taskfn]
+                if not check_setscene_enforce_whitelist(pn, taskname, self.rqdata.setscenewhitelist):
+                    if showerror:
+                        if tid in self.rqdata.runq_setscene_tids:
+                            logger.error('Task %s.%s attempted to execute unexpectedly and should have been setscened' % (pn, taskname))
+                        else:
+                            logger.error('Task %s.%s attempted to execute unexpectedly' % (pn, taskname))
+                    return True
+                return False
+            # Look to see if any tasks that we think shouldn't run are going to
+            unexpected = False
+            for tid in self.rqdata.runtaskentries:
+                if check_norun_task(tid):
+                    unexpected = True
+                    break
+            if unexpected:
+                # Run through the tasks in the rough order they'd have executed and print errors
+                # (since the order can be useful - usually missing sstate for the last few tasks
+                # is the cause of the problem)
+                task = self.sched.next()
+                while task is not None:
+                    check_norun_task(task, showerror=True)
+                    self.task_skip(task, 'Setscene enforcement check')
+                    task = self.sched.next()
+
+                self.rq.state = runQueueCleanUp
+                return True
+
+        self.rq.read_workers()
+
+        if self.stats.total == 0:
+            # nothing to do
+            self.rq.state = runQueueCleanUp
+
+        task = self.sched.next()
+        if task is not None:
+            (mc, fn, taskname, taskfn) = split_tid_mcfn(task)
+
+            if task in self.rq.scenequeue_covered:
+                logger.debug(2, "Setscene covered task %s", task)
+                self.task_skip(task, "covered")
+                return True
+
+            if self.rq.check_stamp_task(task, taskname, cache=self.stampcache):
+                logger.debug(2, "Stamp current task %s", task)
+
+                self.task_skip(task, "existing")
+                return True
+
+            taskdep = self.rqdata.dataCaches[mc].task_deps[taskfn]
+            if 'noexec' in taskdep and taskname in taskdep['noexec']:
+                startevent = runQueueTaskStarted(task, self.stats, self.rq,
+                                                 noexec=True)
+                bb.event.fire(startevent, self.cfgData)
+                self.runq_running.add(task)
+                self.stats.taskActive()
+                if not (self.cooker.configuration.dry_run or self.rqdata.setscene_enforce):
+                    bb.build.make_stamp(taskname, self.rqdata.dataCaches[mc], taskfn)
+                self.task_complete(task)
+                return True
+            else:
+                startevent = runQueueTaskStarted(task, self.stats, self.rq)
+                bb.event.fire(startevent, self.cfgData)
+
+            taskdepdata = self.build_taskdepdata(task)
+
+            taskdep = self.rqdata.dataCaches[mc].task_deps[taskfn]
+            if 'fakeroot' in taskdep and taskname in taskdep['fakeroot'] and not (self.cooker.configuration.dry_run or self.rqdata.setscene_enforce):
+                if not mc in self.rq.fakeworker:
+                    try:
+                        self.rq.start_fakeworker(self, mc)
+                    except OSError as exc:
+                        logger.critical("Failed to spawn fakeroot worker to run %s: %s" % (task, str(exc)))
+                        self.rq.state = runQueueFailed
+                        self.stats.taskFailed()
+                        return True
+                self.rq.fakeworker[mc].process.stdin.write(b"<runtask>" + pickle.dumps((taskfn, task, taskname, False, self.cooker.collection.get_file_appends(taskfn), taskdepdata, self.rqdata.setscene_enforce)) + b"</runtask>")
+                self.rq.fakeworker[mc].process.stdin.flush()
+            else:
+                self.rq.worker[mc].process.stdin.write(b"<runtask>" + pickle.dumps((taskfn, task, taskname, False, self.cooker.collection.get_file_appends(taskfn), taskdepdata, self.rqdata.setscene_enforce)) + b"</runtask>")
+                self.rq.worker[mc].process.stdin.flush()
+
+            self.build_stamps[task] = bb.build.stampfile(taskname, self.rqdata.dataCaches[mc], taskfn, noextra=True)
+            self.build_stamps2.append(self.build_stamps[task])
+            self.runq_running.add(task)
+            self.stats.taskActive()
+            if self.can_start_task():
+                return True
+
+        if self.stats.active > 0:
+            self.rq.read_workers()
+            return self.rq.active_fds()
+
+        if len(self.failed_tids) != 0:
+            self.rq.state = runQueueFailed
+            return True
+
+        # Sanity Checks
+        for task in self.rqdata.runtaskentries:
+            if task not in self.runq_buildable:
+                logger.error("Task %s never buildable!", task)
+            if task not in self.runq_running:
+                logger.error("Task %s never ran!", task)
+            if task not in self.runq_complete:
+                logger.error("Task %s never completed!", task)
+        self.rq.state = runQueueComplete
+
+        return True
+
+    def filtermcdeps(self, task, deps):
+        ret = set()
+        mainmc = mc_from_tid(task)
+        for dep in deps:
+            mc = mc_from_tid(dep)
+            if mc != mainmc:
+                continue
+            ret.add(dep)
+        return ret
+
+    # We filter out multiconfig dependencies from taskdepdata we pass to the tasks 
+    # as most code can't handle them
+    def build_taskdepdata(self, task):
+        taskdepdata = {}
+        next = self.rqdata.runtaskentries[task].depends
+        next.add(task)
+        next = self.filtermcdeps(task, next)
+        while next:
+            additional = []
+            for revdep in next:
+                (mc, fn, taskname, taskfn) = split_tid_mcfn(revdep)
+                pn = self.rqdata.dataCaches[mc].pkg_fn[taskfn]
+                deps = self.rqdata.runtaskentries[revdep].depends
+                provides = self.rqdata.dataCaches[mc].fn_provides[taskfn]
+                taskhash = self.rqdata.runtaskentries[revdep].hash
+                taskdepdata[revdep] = [pn, taskname, fn, deps, provides, taskhash]
+                deps = self.filtermcdeps(task, deps)
+                for revdep2 in deps:
+                    if revdep2 not in taskdepdata:
+                        additional.append(revdep2)
+            next = additional
+
+        #bb.note("Task %s: " % task + str(taskdepdata).replace("], ", "],\n"))
+        return taskdepdata
+
+class RunQueueExecuteScenequeue(RunQueueExecute):
+    def __init__(self, rq):
+        RunQueueExecute.__init__(self, rq)
+
+        self.scenequeue_covered = set()
+        self.scenequeue_notcovered = set()
+        self.scenequeue_notneeded = set()
+
+        # If we don't have any setscene functions, skip this step
+        if len(self.rqdata.runq_setscene_tids) == 0:
+            rq.scenequeue_covered = set()
+            rq.scenequeue_notcovered = set()
+            rq.state = runQueueRunInit
+            return
+
+        self.stats = RunQueueStats(len(self.rqdata.runq_setscene_tids))
+
+        sq_revdeps = {}
+        sq_revdeps_new = {}
+        sq_revdeps_squash = {}
+        self.sq_harddeps = {}
+        self.stamps = {}
+
+        # We need to construct a dependency graph for the setscene functions. Intermediate
+        # dependencies between the setscene tasks only complicate the code. This code
+        # therefore aims to collapse the huge runqueue dependency tree into a smaller one
+        # only containing the setscene functions.
+
+        self.rqdata.init_progress_reporter.next_stage()
+
+        # First process the chains up to the first setscene task.
+        endpoints = {}
+        for tid in self.rqdata.runtaskentries:
+            sq_revdeps[tid] = copy.copy(self.rqdata.runtaskentries[tid].revdeps)
+            sq_revdeps_new[tid] = set()
+            if (len(sq_revdeps[tid]) == 0) and tid not in self.rqdata.runq_setscene_tids:
+                #bb.warn("Added endpoint %s" % (tid))
+                endpoints[tid] = set()
+
+        self.rqdata.init_progress_reporter.next_stage()
+
+        # Secondly process the chains between setscene tasks.
+        for tid in self.rqdata.runq_setscene_tids:
+            #bb.warn("Added endpoint 2 %s" % (tid))
+            for dep in self.rqdata.runtaskentries[tid].depends:
+                    if tid in sq_revdeps[dep]:
+                        sq_revdeps[dep].remove(tid)
+                    if dep not in endpoints:
+                        endpoints[dep] = set()
+                    #bb.warn("  Added endpoint 3 %s" % (dep))
+                    endpoints[dep].add(tid)
+
+        self.rqdata.init_progress_reporter.next_stage()
+
+        def process_endpoints(endpoints):
+            newendpoints = {}
+            for point, task in endpoints.items():
+                tasks = set()
+                if task:
+                    tasks |= task
+                if sq_revdeps_new[point]:
+                    tasks |= sq_revdeps_new[point]
+                sq_revdeps_new[point] = set()
+                if point in self.rqdata.runq_setscene_tids:
+                    sq_revdeps_new[point] = tasks
+                    tasks = set()
+                    continue
+                for dep in self.rqdata.runtaskentries[point].depends:
+                    if point in sq_revdeps[dep]:
+                        sq_revdeps[dep].remove(point)
+                    if tasks:
+                        sq_revdeps_new[dep] |= tasks
+                    if len(sq_revdeps[dep]) == 0 and dep not in self.rqdata.runq_setscene_tids:
+                        newendpoints[dep] = task
+            if len(newendpoints) != 0:
+                process_endpoints(newendpoints)
+
+        process_endpoints(endpoints)
+
+        self.rqdata.init_progress_reporter.next_stage()
+
+        # Build a list of setscene tasks which are "unskippable"
+        # These are direct endpoints referenced by the build
+        endpoints2 = {}
+        sq_revdeps2 = {}
+        sq_revdeps_new2 = {}
+        def process_endpoints2(endpoints):
+            newendpoints = {}
+            for point, task in endpoints.items():
+                tasks = set([point])
+                if task:
+                    tasks |= task
+                if sq_revdeps_new2[point]:
+                    tasks |= sq_revdeps_new2[point]
+                sq_revdeps_new2[point] = set()
+                if point in self.rqdata.runq_setscene_tids:
+                    sq_revdeps_new2[point] = tasks
+                for dep in self.rqdata.runtaskentries[point].depends:
+                    if point in sq_revdeps2[dep]:
+                        sq_revdeps2[dep].remove(point)
+                    if tasks:
+                        sq_revdeps_new2[dep] |= tasks
+                    if (len(sq_revdeps2[dep]) == 0 or len(sq_revdeps_new2[dep]) != 0) and dep not in self.rqdata.runq_setscene_tids:
+                        newendpoints[dep] = tasks
+            if len(newendpoints) != 0:
+                process_endpoints2(newendpoints)
+        for tid in self.rqdata.runtaskentries:
+            sq_revdeps2[tid] = copy.copy(self.rqdata.runtaskentries[tid].revdeps)
+            sq_revdeps_new2[tid] = set()
+            if (len(sq_revdeps2[tid]) == 0) and tid not in self.rqdata.runq_setscene_tids:
+                endpoints2[tid] = set()
+        process_endpoints2(endpoints2)
+        self.unskippable = []
+        for tid in self.rqdata.runq_setscene_tids:
+            if sq_revdeps_new2[tid]:
+                self.unskippable.append(tid)
+
+        self.rqdata.init_progress_reporter.next_stage(len(self.rqdata.runtaskentries))
+
+        for taskcounter, tid in enumerate(self.rqdata.runtaskentries):
+            if tid in self.rqdata.runq_setscene_tids:
+                deps = set()
+                for dep in sq_revdeps_new[tid]:
+                    deps.add(dep)
+                sq_revdeps_squash[tid] = deps
+            elif len(sq_revdeps_new[tid]) != 0:
+                bb.msg.fatal("RunQueue", "Something went badly wrong during scenequeue generation, aborting. Please report this problem.")
+            self.rqdata.init_progress_reporter.update(taskcounter)
+
+        self.rqdata.init_progress_reporter.next_stage()
+
+        # Resolve setscene inter-task dependencies
+        # e.g. do_sometask_setscene[depends] = "targetname:do_someothertask_setscene"
+        # Note that anything explicitly depended upon will have its reverse dependencies removed to avoid circular dependencies
+        for tid in self.rqdata.runq_setscene_tids:
+                (mc, fn, taskname, taskfn) = split_tid_mcfn(tid)
+                realtid = tid + "_setscene"
+                idepends = self.rqdata.taskData[mc].taskentries[realtid].idepends
+                self.stamps[tid] = bb.build.stampfile(taskname + "_setscene", self.rqdata.dataCaches[mc], taskfn, noextra=True)
+                for (depname, idependtask) in idepends:
+
+                    if depname not in self.rqdata.taskData[mc].build_targets:
+                        continue
+
+                    depfn = self.rqdata.taskData[mc].build_targets[depname][0]
+                    if depfn is None:
+                         continue
+                    deptid = depfn + ":" + idependtask.replace("_setscene", "")
+                    if deptid not in self.rqdata.runtaskentries:
+                        bb.msg.fatal("RunQueue", "Task %s depends upon non-existent task %s:%s" % (realtid, depfn, idependtask))
+
+                    if not deptid in self.sq_harddeps:
+                        self.sq_harddeps[deptid] = set()
+                    self.sq_harddeps[deptid].add(tid)
+
+                    sq_revdeps_squash[tid].add(deptid)
+                    # Have to zero this to avoid circular dependencies
+                    sq_revdeps_squash[deptid] = set()
+
+        self.rqdata.init_progress_reporter.next_stage()
+
+        for task in self.sq_harddeps:
+             for dep in self.sq_harddeps[task]:
+                 sq_revdeps_squash[dep].add(task)
+
+        self.rqdata.init_progress_reporter.next_stage()
+
+        #for tid in sq_revdeps_squash:
+        #    for dep in sq_revdeps_squash[tid]:
+        #        data = data + "\n   %s" % dep
+        #    bb.warn("Task %s_setscene: is %s " % (tid, data
+
+        self.sq_deps = {}
+        self.sq_revdeps = sq_revdeps_squash
+        self.sq_revdeps2 = copy.deepcopy(self.sq_revdeps)
+
+        for tid in self.sq_revdeps:
+            self.sq_deps[tid] = set()
+        for tid in self.sq_revdeps:
+            for dep in self.sq_revdeps[tid]:
+                self.sq_deps[dep].add(tid)
+
+        self.rqdata.init_progress_reporter.next_stage()
+
+        for tid in self.sq_revdeps:
+            if len(self.sq_revdeps[tid]) == 0:
+                self.runq_buildable.add(tid)
+
+        self.rqdata.init_progress_reporter.finish()
+
+        self.outrightfail = []
+        if self.rq.hashvalidate:
+            sq_hash = []
+            sq_hashfn = []
+            sq_fn = []
+            sq_taskname = []
+            sq_task = []
+            noexec = []
+            stamppresent = []
+            for tid in self.sq_revdeps:
+                (mc, fn, taskname, taskfn) = split_tid_mcfn(tid)
+
+                taskdep = self.rqdata.dataCaches[mc].task_deps[taskfn]
+
+                if 'noexec' in taskdep and taskname in taskdep['noexec']:
+                    noexec.append(tid)
+                    self.task_skip(tid)
+                    bb.build.make_stamp(taskname + "_setscene", self.rqdata.dataCaches[mc], taskfn)
+                    continue
+
+                if self.rq.check_stamp_task(tid, taskname + "_setscene", cache=self.stampcache):
+                    logger.debug(2, 'Setscene stamp current for task %s', tid)
+                    stamppresent.append(tid)
+                    self.task_skip(tid)
+                    continue
+
+                if self.rq.check_stamp_task(tid, taskname, recurse = True, cache=self.stampcache):
+                    logger.debug(2, 'Normal stamp current for task %s', tid)
+                    stamppresent.append(tid)
+                    self.task_skip(tid)
+                    continue
+
+                sq_fn.append(fn)
+                sq_hashfn.append(self.rqdata.dataCaches[mc].hashfn[taskfn])
+                sq_hash.append(self.rqdata.runtaskentries[tid].hash)
+                sq_taskname.append(taskname)
+                sq_task.append(tid)
+
+            self.cooker.data.setVar("BB_SETSCENE_STAMPCURRENT_COUNT", len(stamppresent))
+
+            call = self.rq.hashvalidate + "(sq_fn, sq_task, sq_hash, sq_hashfn, d)"
+            locs = { "sq_fn" : sq_fn, "sq_task" : sq_taskname, "sq_hash" : sq_hash, "sq_hashfn" : sq_hashfn, "d" : self.cooker.data }
+            valid = bb.utils.better_eval(call, locs)
+
+            self.cooker.data.delVar("BB_SETSCENE_STAMPCURRENT_COUNT")
+
+            valid_new = stamppresent
+            for v in valid:
+                valid_new.append(sq_task[v])
+
+            for tid in self.sq_revdeps:
+                if tid not in valid_new and tid not in noexec:
+                    logger.debug(2, 'No package found, so skipping setscene task %s', tid)
+                    self.outrightfail.append(tid)
+
+        logger.info('Executing SetScene Tasks')
+
+        self.rq.state = runQueueSceneRun
+
+    def scenequeue_updatecounters(self, task, fail = False):
+        for dep in self.sq_deps[task]:
+            if fail and task in self.sq_harddeps and dep in self.sq_harddeps[task]:
+                logger.debug(2, "%s was unavailable and is a hard dependency of %s so skipping" % (task, dep))
+                self.scenequeue_updatecounters(dep, fail)
+                continue
+            if task not in self.sq_revdeps2[dep]:
+                # May already have been removed by the fail case above
+                continue
+            self.sq_revdeps2[dep].remove(task)
+            if len(self.sq_revdeps2[dep]) == 0:
+                self.runq_buildable.add(dep)
+
+    def task_completeoutright(self, task):
+        """
+        Mark a task as completed
+        Look at the reverse dependencies and mark any task with
+        completed dependencies as buildable
+        """
+
+        logger.debug(1, 'Found task %s which could be accelerated', task)
+        self.scenequeue_covered.add(task)
+        self.scenequeue_updatecounters(task)
+
+    def check_taskfail(self, task):
+        if self.rqdata.setscenewhitelist is not None:
+            realtask = task.split('_setscene')[0]
+            (mc, fn, taskname, taskfn) = split_tid_mcfn(realtask)
+            pn = self.rqdata.dataCaches[mc].pkg_fn[taskfn]
+            if not check_setscene_enforce_whitelist(pn, taskname, self.rqdata.setscenewhitelist):
+                logger.error('Task %s.%s failed' % (pn, taskname + "_setscene"))
+                self.rq.state = runQueueCleanUp
+
+    def task_complete(self, task):
+        self.stats.taskCompleted()
+        bb.event.fire(sceneQueueTaskCompleted(task, self.stats, self.rq), self.cfgData)
+        self.task_completeoutright(task)
+
+    def task_fail(self, task, result):
+        self.stats.taskFailed()
+        bb.event.fire(sceneQueueTaskFailed(task, self.stats, result, self), self.cfgData)
+        self.scenequeue_notcovered.add(task)
+        self.scenequeue_updatecounters(task, True)
+        self.check_taskfail(task)
+
+    def task_failoutright(self, task):
+        self.runq_running.add(task)
+        self.runq_buildable.add(task)
+        self.stats.taskSkipped()
+        self.stats.taskCompleted()
+        self.scenequeue_notcovered.add(task)
+        self.scenequeue_updatecounters(task, True)
+
+    def task_skip(self, task):
+        self.runq_running.add(task)
+        self.runq_buildable.add(task)
+        self.task_completeoutright(task)
+        self.stats.taskSkipped()
+        self.stats.taskCompleted()
+
+    def execute(self):
+        """
+        Run the tasks in a queue prepared by prepare_runqueue
+        """
+
+        self.rq.read_workers()
+
+        task = None
+        if self.can_start_task():
+            # Find the next setscene to run
+            for nexttask in self.rqdata.runq_setscene_tids:
+                if nexttask in self.runq_buildable and nexttask not in self.runq_running and self.stamps[nexttask] not in self.build_stamps.values():
+                    if nexttask in self.unskippable:
+                        logger.debug(2, "Setscene task %s is unskippable" % nexttask)
+                    if nexttask not in self.unskippable and len(self.sq_revdeps[nexttask]) > 0 and self.sq_revdeps[nexttask].issubset(self.scenequeue_covered) and self.check_dependencies(nexttask, self.sq_revdeps[nexttask], True):
+                        fn = fn_from_tid(nexttask)
+                        foundtarget = False
+
+                        if nexttask in self.rqdata.target_tids:
+                            foundtarget = True
+                        if not foundtarget:
+                            logger.debug(2, "Skipping setscene for task %s" % nexttask)
+                            self.task_skip(nexttask)
+                            self.scenequeue_notneeded.add(nexttask)
+                            return True
+                    if nexttask in self.outrightfail:
+                        self.task_failoutright(nexttask)
+                        return True
+                    task = nexttask
+                    break
+        if task is not None:
+            (mc, fn, taskname, taskfn) = split_tid_mcfn(task)
+            taskname = taskname + "_setscene"
+            if self.rq.check_stamp_task(task, taskname_from_tid(task), recurse = True, cache=self.stampcache):
+                logger.debug(2, 'Stamp for underlying task %s is current, so skipping setscene variant', task)
+                self.task_failoutright(task)
+                return True
+
+            if self.cooker.configuration.force:
+                if task in self.rqdata.target_tids:
+                    self.task_failoutright(task)
+                    return True
+
+            if self.rq.check_stamp_task(task, taskname, cache=self.stampcache):
+                logger.debug(2, 'Setscene stamp current task %s, so skip it and its dependencies', task)
+                self.task_skip(task)
+                return True
+
+            startevent = sceneQueueTaskStarted(task, self.stats, self.rq)
+            bb.event.fire(startevent, self.cfgData)
+
+            taskdepdata = self.build_taskdepdata(task)
+
+            taskdep = self.rqdata.dataCaches[mc].task_deps[taskfn]
+            if 'fakeroot' in taskdep and taskname in taskdep['fakeroot'] and not self.cooker.configuration.dry_run:
+                if not mc in self.rq.fakeworker:
+                    self.rq.start_fakeworker(self, mc)
+                self.rq.fakeworker[mc].process.stdin.write(b"<runtask>" + pickle.dumps((taskfn, task, taskname, True, self.cooker.collection.get_file_appends(taskfn), taskdepdata, False)) + b"</runtask>")
+                self.rq.fakeworker[mc].process.stdin.flush()
+            else:
+                self.rq.worker[mc].process.stdin.write(b"<runtask>" + pickle.dumps((taskfn, task, taskname, True, self.cooker.collection.get_file_appends(taskfn), taskdepdata, False)) + b"</runtask>")
+                self.rq.worker[mc].process.stdin.flush()
+
+            self.build_stamps[task] = bb.build.stampfile(taskname, self.rqdata.dataCaches[mc], taskfn, noextra=True)
+            self.build_stamps2.append(self.build_stamps[task])
+            self.runq_running.add(task)
+            self.stats.taskActive()
+            if self.can_start_task():
+                return True
+
+        if self.stats.active > 0:
+            self.rq.read_workers()
+            return self.rq.active_fds()
+
+        #for tid in self.sq_revdeps:
+        #    if tid not in self.runq_running:
+        #        buildable = tid in self.runq_buildable
+        #        revdeps = self.sq_revdeps[tid]
+        #        bb.warn("Found we didn't run %s %s %s" % (tid, buildable, str(revdeps)))
+
+        self.rq.scenequeue_covered = self.scenequeue_covered
+        self.rq.scenequeue_notcovered = self.scenequeue_notcovered
+
+        logger.debug(1, 'We can skip tasks %s', "\n".join(sorted(self.rq.scenequeue_covered)))
+
+        self.rq.state = runQueueRunInit
+
+        completeevent = sceneQueueComplete(self.stats, self.rq)
+        bb.event.fire(completeevent, self.cfgData)
+
+        return True
+
+    def runqueue_process_waitpid(self, task, status):
+        RunQueueExecute.runqueue_process_waitpid(self, task, status)
+
+
+    def build_taskdepdata(self, task):
+        def getsetscenedeps(tid):
+            deps = set()
+            (mc, fn, taskname, _) = split_tid_mcfn(tid)
+            realtid = tid + "_setscene"
+            idepends = self.rqdata.taskData[mc].taskentries[realtid].idepends
+            for (depname, idependtask) in idepends:
+                if depname not in self.rqdata.taskData[mc].build_targets:
+                    continue
+
+                depfn = self.rqdata.taskData[mc].build_targets[depname][0]
+                if depfn is None:
+                     continue
+                deptid = depfn + ":" + idependtask.replace("_setscene", "")
+                deps.add(deptid)
+            return deps
+
+        taskdepdata = {}
+        next = getsetscenedeps(task)
+        next.add(task)
+        while next:
+            additional = []
+            for revdep in next:
+                (mc, fn, taskname, taskfn) = split_tid_mcfn(revdep)
+                pn = self.rqdata.dataCaches[mc].pkg_fn[taskfn]
+                deps = getsetscenedeps(revdep)
+                provides = self.rqdata.dataCaches[mc].fn_provides[taskfn]
+                taskhash = self.rqdata.runtaskentries[revdep].hash
+                taskdepdata[revdep] = [pn, taskname, fn, deps, provides, taskhash]
+                for revdep2 in deps:
+                    if revdep2 not in taskdepdata:
+                        additional.append(revdep2)
+            next = additional
+
+        #bb.note("Task %s: " % task + str(taskdepdata).replace("], ", "],\n"))
+        return taskdepdata
+
+class TaskFailure(Exception):
+    """
+    Exception raised when a task in a runqueue fails
+    """
+    def __init__(self, x):
+        self.args = x
+
+
+class runQueueExitWait(bb.event.Event):
+    """
+    Event when waiting for task processes to exit
+    """
+
+    def __init__(self, remain):
+        self.remain = remain
+        self.message = "Waiting for %s active tasks to finish" % remain
+        bb.event.Event.__init__(self)
+
+class runQueueEvent(bb.event.Event):
+    """
+    Base runQueue event class
+    """
+    def __init__(self, task, stats, rq):
+        self.taskid = task
+        self.taskstring = task
+        self.taskname = taskname_from_tid(task)
+        self.taskfile = fn_from_tid(task)
+        self.taskhash = rq.rqdata.get_task_hash(task)
+        self.stats = stats.copy()
+        bb.event.Event.__init__(self)
+
+class sceneQueueEvent(runQueueEvent):
+    """
+    Base sceneQueue event class
+    """
+    def __init__(self, task, stats, rq, noexec=False):
+        runQueueEvent.__init__(self, task, stats, rq)
+        self.taskstring = task + "_setscene"
+        self.taskname = taskname_from_tid(task) + "_setscene"
+        self.taskfile = fn_from_tid(task)
+        self.taskhash = rq.rqdata.get_task_hash(task)
+
+class runQueueTaskStarted(runQueueEvent):
+    """
+    Event notifying a task was started
+    """
+    def __init__(self, task, stats, rq, noexec=False):
+        runQueueEvent.__init__(self, task, stats, rq)
+        self.noexec = noexec
+
+class sceneQueueTaskStarted(sceneQueueEvent):
+    """
+    Event notifying a setscene task was started
+    """
+    def __init__(self, task, stats, rq, noexec=False):
+        sceneQueueEvent.__init__(self, task, stats, rq)
+        self.noexec = noexec
+
+class runQueueTaskFailed(runQueueEvent):
+    """
+    Event notifying a task failed
+    """
+    def __init__(self, task, stats, exitcode, rq):
+        runQueueEvent.__init__(self, task, stats, rq)
+        self.exitcode = exitcode
+
+    def __str__(self):
+        return "Task (%s) failed with exit code '%s'" % (self.taskstring, self.exitcode)
+
+class sceneQueueTaskFailed(sceneQueueEvent):
+    """
+    Event notifying a setscene task failed
+    """
+    def __init__(self, task, stats, exitcode, rq):
+        sceneQueueEvent.__init__(self, task, stats, rq)
+        self.exitcode = exitcode
+
+    def __str__(self):
+        return "Setscene task (%s) failed with exit code '%s' - real task will be run instead" % (self.taskstring, self.exitcode)
+
+class sceneQueueComplete(sceneQueueEvent):
+    """
+    Event when all the sceneQueue tasks are complete
+    """
+    def __init__(self, stats, rq):
+        self.stats = stats.copy()
+        bb.event.Event.__init__(self)
+
+class runQueueTaskCompleted(runQueueEvent):
+    """
+    Event notifying a task completed
+    """
+
+class sceneQueueTaskCompleted(sceneQueueEvent):
+    """
+    Event notifying a setscene task completed
+    """
+
+class runQueueTaskSkipped(runQueueEvent):
+    """
+    Event notifying a task was skipped
+    """
+    def __init__(self, task, stats, rq, reason):
+        runQueueEvent.__init__(self, task, stats, rq)
+        self.reason = reason
+
+class runQueuePipe():
+    """
+    Abstraction for a pipe between a worker thread and the server
+    """
+    def __init__(self, pipein, pipeout, d, rq, rqexec):
+        self.input = pipein
+        if pipeout:
+            pipeout.close()
+        bb.utils.nonblockingfd(self.input)
+        self.queue = b""
+        self.d = d
+        self.rq = rq
+        self.rqexec = rqexec
+
+    def setrunqueueexec(self, rqexec):
+        self.rqexec = rqexec
+
+    def read(self):
+        for workers, name in [(self.rq.worker, "Worker"), (self.rq.fakeworker, "Fakeroot")]:
+            for worker in workers.values():
+                worker.process.poll()
+                if worker.process.returncode is not None and not self.rq.teardown:
+                    bb.error("%s process (%s) exited unexpectedly (%s), shutting down..." % (name, worker.process.pid, str(worker.process.returncode)))
+                    self.rq.finish_runqueue(True)
+
+        start = len(self.queue)
+        try:
+            self.queue = self.queue + (self.input.read(102400) or b"")
+        except (OSError, IOError) as e:
+            if e.errno != errno.EAGAIN:
+                raise
+        end = len(self.queue)
+        found = True
+        while found and len(self.queue):
+            found = False
+            index = self.queue.find(b"</event>")
+            while index != -1 and self.queue.startswith(b"<event>"):
+                try:
+                    event = pickle.loads(self.queue[7:index])
+                except ValueError as e:
+                    bb.msg.fatal("RunQueue", "failed load pickle '%s': '%s'" % (e, self.queue[7:index]))
+                bb.event.fire_from_worker(event, self.d)
+                found = True
+                self.queue = self.queue[index+8:]
+                index = self.queue.find(b"</event>")
+            index = self.queue.find(b"</exitcode>")
+            while index != -1 and self.queue.startswith(b"<exitcode>"):
+                try:
+                    task, status = pickle.loads(self.queue[10:index])
+                except ValueError as e:
+                    bb.msg.fatal("RunQueue", "failed load pickle '%s': '%s'" % (e, self.queue[10:index]))
+                self.rqexec.runqueue_process_waitpid(task, status)
+                found = True
+                self.queue = self.queue[index+11:]
+                index = self.queue.find(b"</exitcode>")
+        return (end > start)
+
+    def close(self):
+        while self.read():
+            continue
+        if len(self.queue) > 0:
+            print("Warning, worker left partial message: %s" % self.queue)
+        self.input.close()
+
+def get_setscene_enforce_whitelist(d):
+    if d.getVar('BB_SETSCENE_ENFORCE') != '1':
+        return None
+    whitelist = (d.getVar("BB_SETSCENE_ENFORCE_WHITELIST") or "").split()
+    outlist = []
+    for item in whitelist[:]:
+        if item.startswith('%:'):
+            for target in sys.argv[1:]:
+                if not target.startswith('-'):
+                    outlist.append(target.split(':')[0] + ':' + item.split(':')[1])
+        else:
+            outlist.append(item)
+    return outlist
+
+def check_setscene_enforce_whitelist(pn, taskname, whitelist):
+    import fnmatch
+    if whitelist is not None:
+        item = '%s:%s' % (pn, taskname)
+        for whitelist_item in whitelist:
+            if fnmatch.fnmatch(item, whitelist_item):
+                return True
+        return False
+    return True