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| author | Tiago Muck <tiago.muck@arm.com> | 2019-02-25 16:20:32 -0600 |
|---|---|---|
| committer | Tiago Mück <tiago.muck@arm.com> | 2019-05-14 22:01:12 +0000 |
| commit | 42e55cdafdac41830839ac2584d99a8dd5e3d95e (patch) | |
| tree | 0c9b4e7e33eef0c731be478b43424c266e36c2d1 /src/mem/ruby/slicc_interface/Controller.py | |
| parent | 575ac7a14a5f5f242f903949219dbdc310747915 (diff) | |
| download | gem5-42e55cdafdac41830839ac2584d99a8dd5e3d95e.tar.xz | |
mem-ruby: Do not change blocked msg enqueue info
Updating the message counter and enqueue times when adding blocked
messages back to the queue does not make a lot of sense since these
messages are not new arrivals.
More importantly, this may lead to starvation. See the scenario below:
1) Request A for a blocked line X arrives
2) A is handled; X is blocked so A is stalled
3) Request B for X arrives; Reponse for X arrives
4) Response is handled; X unblocked; A added back to the request queue
5) B is handled ahead of A (since A's arrival was updated);
X may become blocked again
If new requests keep comming for X, A may will be stalled forever.
Change-Id: Icad79f3f716a870e91cb3455437b8b3c35f130ac
Signed-off-by: Tiago Muck <tiago.muck@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/18412
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Matthew Poremba <matthew.poremba@amd.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>
Diffstat (limited to 'src/mem/ruby/slicc_interface/Controller.py')
0 files changed, 0 insertions, 0 deletions