This chapter is from the book
This chapter is from the book
This chapter is from the book
Exercises
11.1 Modify the example code shown in Figure 11.4 to pass the structure between the threads properly.
11.2 In the example code shown in Figure 11.14, what additional synchronization (if any) is necessary to allow the master thread to change the thread ID associated with a pending job? How would this affect the job_remove function?
11.3 Apply the techniques shown in Figure 11.15 to the worker thread example (Figures 11.1 and 11.14) to implement the worker thread function. Don’t forget to update the queue_init function to initialize the condition variable and change the job_insert and job_append functions to signal the worker threads. What difficulties arise?
11.4 Which sequence of steps is correct?
- Lock a mutex (pthread_mutex_lock).
- Change the condition protected by the mutex.
- Signal threads waiting on the condition (pthread_cond_broadcast).
- Unlock the mutex (pthread_mutex_unlock).
or
- Lock a mutex (pthread_mutex_lock).
- Change the condition protected by the mutex.
- Unlock the mutex (pthread_mutex_unlock).
- Signal threads waiting on the condition (pthread_cond_broadcast).
11.5 What synchronization primitives would you need to implement a barrier? Provide an implementation of the pthread_barrier_wait function.