path: root/meta/lib/oe/
diff options
authorRichard Purdie <>2019-02-16 14:01:56 (GMT)
committerRichard Purdie <>2019-02-17 10:19:59 (GMT)
commitf3e56f1b57584a136e14386fec2de95e73960eb4 (patch)
treed230ee269b9628b9fc976437f609b91996413d00 /meta/lib/oe/
parent050aab7f45ed13e01da5ff760e8292c091b27ee6 (diff)
lib/oe/utils: Fix hang in multiprocess_launch()
If large results values are returned by the subprocesses, we can hit a deadlock where the subprocess is trying to write data back to the parent, the pipe is full and the parent is waiting for the child to exit. Avoid this by calling the update() method which would trigger reading a result from the child, avoiding the deadlock. The issue is described in (From OE-Core rev: 0035e8066ecbbff94d6a1994a9f72b1368d660d2) Signed-off-by: Richard Purdie <>
Diffstat (limited to 'meta/lib/oe/')
1 files changed, 4 insertions, 0 deletions
diff --git a/meta/lib/oe/ b/meta/lib/oe/
index 0c1d48a..3a49609 100644
--- a/meta/lib/oe/
+++ b/meta/lib/oe/
@@ -307,6 +307,10 @@ def multiprocess_launch(target, items, d, extraargs=None):
307 p.start() 307 p.start()
308 launched.append(p) 308 launched.append(p)
309 for q in launched: 309 for q in launched:
310 # Have to manually call update() to avoid deadlocks. The pipe can be full and
311 # transfer stalled until we try and read the results object but the subprocess won't exit
312 # as it still has data to write (
313 q.update()
310 # The finished processes are joined when calling is_alive() 314 # The finished processes are joined when calling is_alive()
311 if not q.is_alive(): 315 if not q.is_alive():
312 if q.exception: 316 if q.exception: