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IPDL/Proposal:Shmem access control: Difference between revisions
IPDL/Proposal:Shmem access control (view source)
Revision as of 17:21, 27 October 2009
, 27 October 2009→Optional fine-grained access change for Shmem
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# No write/write hazards: only one actor may have write access (or have reserved it). | # No write/write hazards: only one actor may have write access (or have reserved it). | ||
# No read/write hazards: one actor cannot have +r while the other has +w | # No read/write hazards: one actor cannot have +r while the other has +w | ||
# Shmem "chmod" messages may not race. (It's rather difficult, but possible, to guarantee that access bits stay consistent and hazard free. Deferring.) | |||
The IPDL compiler can only sanity check transfers; it can't do full checking statically, since it doesn't know about "particular" shmem instances. The dynamic check is basically free, though. | The IPDL compiler can only sanity check transfers; it can't do full checking statically, since it doesn't know about "particular" shmem instances. The dynamic check is basically free, though. | ||