On Fri, 2008-08-15 at 16:28 -0400, Gregory Haskins wrote: > The kernel currently addresses priority-inversion through priority- > inheritence. However, all of the priority-inheritence logic is > integrated into the Real-Time Mutex infrastructure. This causes a few > problems: > > 1) This tightly coupled relationship makes it difficult to extend to > other areas of the kernel (for instance, pi-aware wait-queues may > be desirable). > 2) Enhancing the rtmutex infrastructure becomes challenging because > there is no seperation between the locking code, and the pi-code. > > This patch aims to rectify these shortcomings by designing a stand-alone > pi framework which can then be used to replace the rtmutex-specific > version. The goal of this framework is to provide similar functionality > to the existing subsystem, but with sole focus on PI and the > relationships between objects that can boost priority, and the objects > that get boosted. > > We introduce the concept of a "pi_source" and a "pi_sink", where, as the > name suggests provides the basic relationship of a priority source, and > its boosted target. A pi_source acts as a reference to some arbitrary > source of priority, and a pi_sink can be boosted (or deboosted) by > a pi_source. For more details, please read the library documentation. > > There are currently no users of this inteface. You should have started out by discussing your design - the document just rambles a bit about some implementation details - it doesn't talk about how it maps to the PI problem space. Anyway - from what I can make of the code, you managed to convert the pi graph walking code that used to be in rt_mutex_adjust_prio_chain() and was iterative, into a recursive function call. Not something you should do lightly.. -- To unsubscribe from this list: send the line "unsubscribe linux-rt-users" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
