Major SMP Improvements

Sebastian Huber sebastian.huber at
Fri May 15 11:41:00 UTC 2015

It provides a major performance boost for SMP configurations, see and

It was tested on the Altera Cyclone V, ESA/Gaisler NGMP and Freescale T4240
platforms using the standard RTEMS testsuite, a randomized test case that
covers the thread queue and watchdog implementation (it run several days) and
with heavy load network traffic using the new network stack (it uses hundreds
of locks). After two years of work all tests pass now on the NGMP platform in
uni-processor and SMP configurations.

The BSPs compile and link the samples using the latest RSB based tool chain
(except targets with a broken compiler, e.g. AVR, Moxie).

With this patch set the SMP support of RTEMS can be considered to be
practically useful on targets with more than two processors.  This is
definitely not the case for the current Git master (possible RTEMS 4.11).  Also
timestamps are broken on SMP in the current Git master.  So it may make sense
to include this patch set in the RTEMS 4.11 release.  We don't have additional
RTEMS work in the next three months planned so this is the last big change set
for a while.

This work was sponsored by the European Space Agency (ESA).

More information about the devel mailing list