ttas_spin_lock.cpp

#include "pls/internal/helpers/profiler.h"
#include "pls/internal/base/ttas_spin_lock.h"

namespace pls {
    namespace internal {
        namespace base {
            void ttas_spin_lock::lock() {
                PROFILE_LOCK("Acquire Lock")
                int tries = 0;
                int expected = 0;

                do {
                    while (flag_.load(std::memory_order_relaxed) == 1) {
                        tries++;
                        if (tries % yield_at_tries_ == 0) {
                            this_thread::yield();
                        }
                    }

                    expected = 0;
                } while (!flag_.compare_exchange_weak(expected, 1, std::memory_order_acquire));
            }

            bool ttas_spin_lock::try_lock(unsigned int num_tries) {
                PROFILE_LOCK("Try Acquire Lock")
                int expected = 0;

                do {
                    while (flag_.load(std::memory_order_relaxed) == 1) {
                        num_tries--;
                        if (num_tries <= 0) {
                            return false;
                        }
                    }

                    expected = 0;
                } while (!flag_.compare_exchange_weak(expected, 1, std::memory_order_acquire));

                return true;
            }

            void ttas_spin_lock::unlock() {
                flag_.store(0, std::memory_order_release);
            }
        }
    }
}