diff -r 956922c80481 -r 8495d879012b pip.html --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/pip.html Tue Feb 14 03:27:06 2012 +0000 @@ -0,0 +1,57 @@ +<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN" +"http://www.w3.org/TR/REC-html40/loose.dtd"> +<HEAD> +<TITLE>Priority Inversion Protocol</TITLE> +<BASE HREF="http://www.dcs.kcl.ac.uk/staff/urbanc/"> +</HEAD> + +<BODY TEXT="#000000" + BGCOLOR="#4169E1" + LINK="#0000EF" + VLINK="#51188E" + ALINK="#FF0000"> + +<TABLE WIDTH="100%" + BGCOLOR="#4169E1" + BORDER="0" + FRAME="border" + CELLPADDING="10" + CELLSPACING="2" + RULES="all"> + +<!-- right column --> +<TR> +<TD BGCOLOR="#FFFFFF" WIDTH="75%"> +<H2>Proving the Priority Inheritance Protocol Correct</H2> + +By Xingyuan Zhang, Christian Urban and Chunhan Wu +<p> +In real-time systems with threads, resource locking and +priority scheduling, one faces the problem of Priority +Inversion. This problem can make the behaviour of threads +unpredictable and the resulting bugs can be hard to find. The +Priority Inheritance Protocol is one solution implemented in many +systems for solving this problem, but the correctness of this solution +has never been formally verified in a theorem prover. As already +pointed out in the literature, the original informal investigation of +the Property Inheritance Protocol presents a correctness "proof" for +an incorrect algorithm. In this paper we fix the problem of +this proof by making all notions precise and implementing a variant of +a solution proposed earlier. Our formalisation in Isabelle/HOL +uncovers facts not mentioned in the literature, but also shows how to +efficiently implement this protocol. Earlier correct implementations +were criticised as too inefficient. Our formalisation is based on +Paulson's inductive approach to verifying protocols. +<BR><BR> + + +<BR><BR><BR><BR> + +</TABLE> +<P><!-- Created: Tue Mar 4 00:23:25 GMT 1997 --> +<!-- hhmts start --> +Last modified: Thu Feb 28 20:24:23 CET 2008 +<!-- hhmts end --> +<a href="http://validator.w3.org/check/referer">[Validate this page.]</a> +</BODY> +</HTML>