Methods and apparatus for detecting deadlock in multithreading programs

Abstract

A method of detecting deadlock in a multithreading program is provided. An invocation graph is constructed having a single root and a plurality of nodes corresponding to one or more functions written in code of the multithreading program. A resource graph is computed in accordance with one or more resource sets in effect at each node of the invocation graph. It is determined whether cycles exist between two or more nodes of the resource graph. A cycle is an indication of deadlock in the multithreading program.

Description

FIELD OF THE INVENTION [0001] The present invention relates generally to multithreading programs and, more particularly, to techniques for detecting deadlock in multithreading programs. BACKGROUND OF THE INVENTION [0002] Deadlock is a pernicious condition in which multiple processes are prohibited from making progress, because each is waiting for one or more resources that are being used by some other process. However, deadlock is difficult to detect because it may occur only under specific conditions involving, for example, the interleaving or timing of the executing threads. [0003] In a simple example of deadlock, an operating system contains two files, file1 and file2. Two concurrently running processes, thread1 and thread2, both require file1 and file2 to complete successfully. If thread1 opens file1, and thread2 opens file2, deadlock may result when thread1 attempts to open file2 before closing file1, and thread2 attempts to open file1 before closing file2. Thus, the two proces...

AI Technical Summary

Benefits of technology

[0016] The approach of the present invention includes detailed reporting at both the interprocedural and intraprocedural level allowing for the clear identification of resource contention locations. The method is general in that it works on a resource cycle strategy through an abstract description of the program involving graphs and not details of the programming language. Thus, the embodiments of the present invention may be applied to any language which implements monitors and may be scaled to large problems.

Problems solved by technology

Deadlock is a pernicious condition in which multiple processes are prohibited from making progress, because each is waiting for one or more resources that are being used by some other process.

However, deadlock is difficult to detect because it may occur only under specific conditions involving, for example, the interleaving or timing of the executing threads.

Images