What are the methods for synchronizing threads in Linux?

There are several methods of thread synchronization in the Linux operating system.

1. Mutex: Utilize a mutex of type pthread_mutex_t to protect critical sections, ensuring that only one thread can access shared resources at a time. Acquire the lock using the pthread_mutex_lock() function and release it using the pthread_mutex_unlock() function.
2. Condition variable: Use a pthread_cond_t type variable to facilitate communication and synchronization between threads. Threads wait on the condition variable for a specific condition to be met, and when the condition is satisfied, other threads can notify the waiting threads using pthread_cond_signal() or pthread_cond_broadcast().
3. Spin Lock: Implement simple mutual exclusion using a spin lock of type pthread_spinlock_t. Spin locks do not block when trying to acquire the lock, but instead continuously wait until the lock is acquired. Use pthread_spin_lock() to acquire the lock and pthread_spin_unlock() to release it.
4. Semaphore: Utilizing sem_t type semaphore to regulate multiple threads’ access to shared resources. Semaphores can achieve mutual exclusion and synchronization among threads, waiting for a semaphore with sem_wait() function and releasing a semaphore with sem_post() function.
5. Barrier: Using a barrier of type pthread_barrier_t to synchronize multiple threads to execute at a certain point. When all threads reach the barrier, they will continue executing together.
6. Read-Write Lock: Utilize a read-write lock of type pthread_rwlock_t to allow multiple threads to read shared resources simultaneously, but only permit one thread to write to the shared resources. Acquire a read lock using the pthread_rwlock_rdlock() function, and a write lock using the pthread_rwlock_wrlock() function.