Collaboration diagram for Critical sections:

Used to protect short regions of code against concurrent access.

• Your system is a bare-metal system (probably with an RTOS) and interrupts are under your control: Implement this as LockInterrupts() / UnlockInterrupts()
• Your system uses an RTOS with deferred interrupt handling from a worker thread: Implement as a global mutex or lock/unlock scheduler
• Your system uses a high-level OS with e.g. POSIX signals: Implement as a global mutex