Meaning
Hardware-supported and software-supported exchange of information allows multiple processor cores on a single system-on-chip or board to coordinate tasks and share memory resources. In multi-core embedded systems, inter processor communication relies on shared memory regions and hardware mailboxes to pass data and signal events without collision. This capability is important for heterogeneous systems where an application processor runs beside a real-time coprocessor.
Transfer Mechanism
Coordination between cores uses dedicated hardware interrupt lines to trigger execution upon data arrival. When one core writes data to a designated shared memory segment, it asserts a hardware event that alerts the receiving core. Utilizing inter processor communication ensures that both processors can operate on the same data block without the risk of simultaneous writes.
Synchronization Method
Locking mechanisms prevent concurrent access to shared buffers by using hardware-enforced semaphores that can only be claimed by one processor at a time. This hardware lock ensures that a master processor cannot overwrite a message before the slave processor has finished reading it. A failing attempt to acquire the semaphore forces the requesting processor to either poll the status or execute a low-power wait instruction until the resource is freed.
Core Overhead
Communication overhead can limit the scaling of multi-core systems. Designers minimize this by using zero-copy buffers.
