By Cormac Flanagan, Stephen N. Freund

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Atomizer A Dynamic Atomicity Checker For
Multithreaded Programs

• By Cormac Flanagan, Stephen N. Freund
• 24th April, 2008
• Hong,Shin

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Contents

• Introduction
• Multithreaded Programs
• Formal definition of multithreaded program
• The standard semantics of execution
• The serialized semantics of execution
• Atomicity requirements
• Dynamic Atomicity Checking
• Reduction
• Checking atomicity via reduction
• Inferring Protecting Locks

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Introduction 1/4

• A race condition occurs when two threads
  simultaneously access the same data variable, and
  at least one of the access is a write.
• In practice, race conditions are commonly avoided
  by protecting each data structure with a lock.
• Unfortunately, the absence of race condition is
  not sufficient to ensure the absence of errors
  due to unexpected interference between threads.

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Introduction 2/4

• Example java.lang.StringBuffer

• public final class StringBuffer
• public synchronized int length()