Fine-grained multiprocessor real-time locking with improved blocking

Existing multiprocessor real-time locking protocols that sup-port nesting are subject to adverse blocking that can be avoided when additional resource-usage-pattern information is known. These sources of blocking stem from system over-heads, varying critical section lengths, and a lack of sup-port for replicated resources. In this paper, these issues are resolved in the context of the recently proposed real-time nested locking protocol (RNLP). The resulting protocols are the first to support fine-grained real-time lock nesting while allowing multiple resources to be locked in one atomic op-eration, both spin- and suspension-based waiting to be used together, and resources to be replicated. They also reduce “short-on-long ” blocking, which is very detrimental if both very long and very short critical sections must be supported. 1