bitbake: Use a "fork" multiprocessing context

Python 3.14 changes the default multiprocessing context from "fork" to
"forkserver"; however bitbake heavily relies on "fork" to efficiently
pass data to the child processes. As such, make "fork" context in the bb
namespace and use it in place of the normal multiprocessing module.

Note that multiprocessing contexts were added in Python 3.4, so this
should be safe to use even before Python 3.14

[YOCTO #15858]

(Bitbake rev: 0d9d8d0863e82e986c33c08064ce9a99224a06d5)

Signed-off-by: Joshua Watt <JPEWhacker@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
Signed-off-by: Steve Sakoman <steve@sakoman.com>

1 files changed, 1 insertions, 3 deletions

diff --git a/bitbake/lib/bb/utils.py b/bitbake/lib/bb/utils.py
index 0832422683..694e79f552 100644
--- a/bitbake/lib/bb/utils.py
+++ b/bitbake/lib/bb/utils.py
@@ -12,7 +12,7 @@ import sys
 import errno
 import logging
 import locale
-import multiprocessing
+from bb import multiprocessing
 import importlib
 import importlib.machinery
 import importlib.util
@@ -1198,8 +1198,6 @@ def process_profilelog(fn, pout = None):
 #
 def multiprocessingpool(*args, **kwargs):
 
-    import multiprocessing.pool
-    #import multiprocessing.util
     #multiprocessing.util.log_to_stderr(10)
     # Deal with a multiprocessing bug where signals to the processes would be delayed until the work
     # completes. Putting in a timeout means the signals (like SIGINT/SIGTERM) get processed.