An optimal k-exclusion real-time locking protocol motivated by multi-GPU systems

Abstract

Graphics processing units (GPUs) are becoming increasingly important in today's platforms as their increased generality allows for them to be used as powerful co-processors. In previous work, we have found that GPUs may be integrated into real-time systems through the treatment of GPUs as shared resources, allocated to real-time tasks through mutual exclusion locking protocols. In this paper, we present an optimal k-exclusion locking protocol for globally-scheduled job-level static-priority (JLSP) systems. This protocol may be used to manage a pool of GPU resources in such systems.

Supporting Nested Locking in Multiprocessor Real-Time Systems

“…The O-KGLP is a k-exclusion lock, and thus satisfies Property T1. By Theorem 1 of [8], the O-KGLP is asymptotically optimal, and progress is ensured because of the bounded duration of pi-block in each component of the O-KGLP by Lemmas 2-5 and 7 of [8]. Thus Property T2 holds under the O-KGLP.…”

“…Elliott and Anderson developed a k-exclusion locking protocol specifically for globally scheduled systems called the O-KGLP [8]. In the O-KGLP, non-resource-requesting jobs are not affected by the behavior of the locking protocol.…”

“…From Lemmas 2-5 and 7 of [8], the maximum piblocking per token request is 2m/k + 2 times the maximum duration of time a job can hold a token (i.e., the "maximum critical section length" from the perspective of the O-KGLP). By Lemma 1 (of this paper), a token-holding job can be blocked by k − 1 requests, and thus the maximum duration of time a job can hold a token is kL max .…”

Fine-grained multiprocessor real-time locking with improved blocking

“…We do this by leveraging recent work on asymptotically optimal realtime k-exclusion protocols [7,8,13]. Such protocols provide a limited form of replication: they enable requests to be performed on k replicas of a single resource.…”

Robust Real-Time Multiprocessor Interrupt Handling Motivated by GPUs

“…10 A full description of the k-FMLP is available in Appendix A of the online version of this paper at http://www.cs.unc.edu/~anderson/ papers.html. A detailed discussion of some issues that arise when constructing a real-time k-exclusion protocol can be found in [30].…”