ruby, arm: Forward invalidations to the local exclusive monitor

ARM systems require local exclusive monitors for the implementation of
synchronization primitives between processors. A ruby memory system
needs to forward invalidations to the local exclusive monitors to
to correctly determine their state.

Change-Id: I7bc4d0f2a5be0f4e36a25c87aa4a81a3f086fb3c
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/2904
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>

diff --git a/configs/ruby/Ruby.py b/configs/ruby/Ruby.py
index 71f6eef7ca598c2a469f9ffda3f87402b6c7d8bb..04eda5a391352e142181bfd9790b70bf5ae70f36 100644 (file)
--- a/configs/ruby/Ruby.py
+++ b/configs/ruby/Ruby.py
@@ -231,6 +231,8 @@ def send_evicts(options):
     # currently, 2 scenarios warrant forwarding evictions to the CPU:
     # 1. The O3 model must keep the LSQ coherent with the caches
     # 2. The x86 mwait instruction is built on top of coherence invalidations
-    if options.cpu_type == "DerivO3CPU" or buildEnv['TARGET_ISA'] == 'x86':
+    # 3. The local exclusive monitor in ARM systems
+    if options.cpu_type == "DerivO3CPU" or \
+       buildEnv['TARGET_ISA'] in ('x86', 'arm'):
         return True
     return False