bitbake: knotty/uihelper: Switch from pids to tids for Task event management

We've seen cases where a task can execute with a given pid, complete
and a new task can start using the same pid before the UI handler has
had time to adapt.

Traceback (most recent call last):
  File "/home/pokybuild/yocto-worker/qemux86-alt/build/bitbake/lib/bb/ui/knotty.py", line 484, in main
    helper.eventHandler(event)
  File "/home/pokybuild/yocto-worker/qemux86-alt/build/bitbake/lib/bb/ui/uihelper.py", line 30, in eventHandler
    del self.running_tasks[event.pid]
KeyError: 13490

This means using pids to match up events on the UI side is a bad
idea. Change the code to use task ids instead. There is a small
amount of fuzzy matching for the progress information since there
is no task information there and we don't want the overhead of a task
ID in every event, however since pid reuse is unlikely, we can live
with a progress bar not quite working properly in a corner case like
this.

[YOCTO #13667]

(Bitbake rev: e427eafa1bb04008d12100ccc5c862122bba53e0)

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

1 files changed, 24 insertions, 15 deletions

diff --git a/bitbake/lib/bb/ui/uihelper.py b/bitbake/lib/bb/ui/uihelper.py
index c8dd7df087..48d808ae28 100644
--- a/bitbake/lib/bb/ui/uihelper.py
+++ b/bitbake/lib/bb/ui/uihelper.py
@@ -15,39 +15,48 @@ class BBUIHelper:
         # Running PIDs preserves the order tasks were executed in
         self.running_pids = []
         self.failed_tasks = []
+        self.pidmap = {}
         self.tasknumber_current = 0
         self.tasknumber_total = 0
 
     def eventHandler(self, event):
+        # PIDs are a bad idea as they can be reused before we process all UI events.
+        # We maintain a 'fuzzy' match for TaskProgress since there is no other way to match
+        def removetid(pid, tid):
+            self.running_pids.remove(tid)
+            del self.running_tasks[tid]
+            if self.pidmap[pid] == tid:
+                del self.pidmap[pid]
+            self.needUpdate = True
+
         if isinstance(event, bb.build.TaskStarted):
+            tid = event._fn + ":" + event._task
             if event._mc != "default":
-                self.running_tasks[event.pid] = { 'title' : "mc:%s:%s %s" % (event._mc, event._package, event._task), 'starttime' : time.time() }
+                self.running_tasks[tid] = { 'title' : "mc:%s:%s %s" % (event._mc, event._package, event._task), 'starttime' : time.time(), 'pid' : event.pid }
             else:
-                self.running_tasks[event.pid] = { 'title' : "%s %s" % (event._package, event._task), 'starttime' : time.time() }
-            self.running_pids.append(event.pid)
+                self.running_tasks[tid] = { 'title' : "%s %s" % (event._package, event._task), 'starttime' : time.time(), 'pid' : event.pid }
+            self.running_pids.append(tid)
+            self.pidmap[event.pid] = tid
             self.needUpdate = True
         elif isinstance(event, bb.build.TaskSucceeded):
-            del self.running_tasks[event.pid]
-            self.running_pids.remove(event.pid)
-            self.needUpdate = True
+            tid = event._fn + ":" + event._task
+            removetid(event.pid, tid)
         elif isinstance(event, bb.build.TaskFailedSilent):
-            del self.running_tasks[event.pid]
-            self.running_pids.remove(event.pid)
+            tid = event._fn + ":" + event._task
+            removetid(event.pid, tid)
             # Don't add to the failed tasks list since this is e.g. a setscene task failure
-            self.needUpdate = True
         elif isinstance(event, bb.build.TaskFailed):
-            del self.running_tasks[event.pid]
-            self.running_pids.remove(event.pid)
+            tid = event._fn + ":" + event._task
+            removetid(event.pid, tid)
             self.failed_tasks.append( { 'title' : "%s %s" % (event._package, event._task)})
-            self.needUpdate = True
         elif isinstance(event, bb.runqueue.runQueueTaskStarted):
             self.tasknumber_current = event.stats.completed + event.stats.active + event.stats.failed + 1
             self.tasknumber_total = event.stats.total
             self.needUpdate = True
         elif isinstance(event, bb.build.TaskProgress):
-            if event.pid > 0:
-                self.running_tasks[event.pid]['progress'] = event.progress
-                self.running_tasks[event.pid]['rate'] = event.rate
+            if event.pid > 0 and event.pid in self.pidmap:
+                self.running_tasks[self.pidmap[event.pid]]['progress'] = event.progress
+                self.running_tasks[self.pidmap[event.pid]]['rate'] = event.rate
                 self.needUpdate = True
         else:
             return False