CS433 aassignment 2

Synchronization of Parallel Programs using Locks and Barriers

This repository contains code for implementing Locks and Barriers in parallel programs using various algorithms.

sync_lib.c contains all algorithms in one place.

Additionally lock algorithms are present under Locks Folder and barrier algorithms under Barriers Folder.

Locks

Locks contains 8 different lock algorithms. We have implemented the following locks:

• lock_omp_critical.c - Lock using #pragma omp critical of OpenMP
• lock_posix.c - Lock using pthread mutex locks of POSIX Threads
• lock_semaphores.c - Lock using binary semaphores implemented using POSIX Threads
• lock_spin.c - Spin Lock using cmpxchg
• lock_lamport.c - Lamport Bakery lock algorithm using POSIX Threads
• TTS.c - Test Test and Set lock algorithm using cmpxchg with POSIX Threads
• lock_ticket.c - Ticket Lock using fetch and increment implemented using cmpxchg with POSIX Threads
• lock_array.c - Array Lock using fetch and increment implemented using cmpxchg with POSIX Threads

Barriers

Barriers contains 6 different barrier algorithms. We have implemented the following barriers:

• Centralised_Barrier.c : Centralised Barrier with sense reversal implemented using pthread mutex and POSIX Threads
• Barrier_Posix_interface.c : Barrier using the pthread_barrier of POSIX Threads
• Posix_conditional.c : Barrier using POSIX conditional variables
• Tree_Busy_Wait.c : Tree Barrier using busy wait flags and POSIX Threads
• Tree_CV.c : Tree Barrier using POSIX condtional variables
• barrier_omp.c : Barrier using #pragma omp barrier of OpenMP

Compiling and Running Code

Compile the code using: To run any lock/barrier algorithm just uncomment the corresponding main_{} function in the main() of sync_lib.c

To compile sync_lib

gcc -O0 -pthread -fopenmp sync_lib.c -o sync_lib

Running the code

./sync_lib N where N is the number of threads to run in the program.