Concurrency Control & Coordination

Synchronization Mechanisms

Mutual Exclusion

• Exclusive access to only one thread at at time
• mutex

Waiting on other threads

• Specific condition before proceeding
• Condition variable

Thread Creation

Thread type

• Thread data structure
• thread ID, PC, Stack Pointer, registers, stack, other attributes

Fork(procedure, args)

• create a thread
• not UNIX system fork

Join(thread)

• terminate a thread

Thread thread1;
Shared_list list;
thread1 = fork(safe_insert, 4);
safe_insert(6);
join(thread1); // wait until t1 completes