tree e9fba72ad3e991d1fb1a6d8f177a60ec57d58f60
parent 2757368c842e445b7dad79941172e396a14d58d5
author Pouya Fotouhi <pfotouhi@ucdavis.edu> 1551302722 -0800
committer Pouya Fotouhi <pfotouhi@ucdavis.edu> 1563901179 +0000

mem-ruby: Adding a new slicc statement - to not evict locked cachelines

Ruby caches block incoming ports with messages on a locked
address to make sure the line would not be replaced by others.
But they do not check the lock upon capacity/conflict misses.

This change adds a new slicc statement "check_on_cache_probe" which takes
two arguments (mandatoryQueue for the controller, and the line subject
to eviction - i.e. address returned by cacheProbe).
If the line is locked, incoming message is delayed for 1 cycle and the
controller skips this request (i.e. does not trigger an event).

Coherence protocols should be updated accordingly. One use case for MESI
Two Level will be added in a separate change.

Signed-off-by: Pouya Fotouhi <pfotouhi@ucdavis.edu>
Change-Id: I79ca2d45518de7a4e382b520a11f8e221b0cb803
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/16808
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Srikant Bharadwaj <srikant.bharadwaj@amd.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>