GPU CTA Synchronization via Atomic Semaphore Arrays

The patent extracts the synchronization function from the interrupt-based system and implements it using atomic operations within the GPU's parallel processing architecture. The atomic add operation to increment the semaphore counter and the atomic compare-exchange operation to check for completion are executed directly by the thread array without involving the CPU interrupt system, thereby eliminating repetitive interrupt traffic while maintaining synchronization reliability.

The patent introduces a semaphore counter as an intermediary data structure that mediates synchronization between CTAs. Instead of using CPU interrupts as the intermediary mechanism, the semaphore counter allows threads to coordinate their execution progress through atomic operations, reducing the need for CPU intervention and improving overall system performance.

The patent extracts the synchronization checkpoint mechanism from the interrupt-driven model and implements it using atomic operations. Each synchronization point uses an atomic add operation to increment a semaphore counter and an atomic compare-exchange operation to verify completion, allowing multiple checkpoints to be established without generating proportional interrupt traffic.

The patent enables continuous synchronization operations within the GPU's parallel processing stream. By using atomic operations that can be executed continuously by the thread array without CPU intervention, the system maintains multiple synchronization checkpoints while avoiding the disruptive nature of repetitive interrupts, thus reducing interrupt traffic volume.

The patent substitutes the mechanical interrupt-based synchronization system with a software-based atomic operation system. Instead of relying on hardware interrupts and OS-level interrupt handling, the synchronization is achieved through atomic read-modify-write operations executed directly by the GPU's parallel processing units, eliminating the fundamental constraint of interrupt service time.

The patent implements self-service synchronization where the thread arrays perform their own synchronization operations using atomic instructions. The threads autonomously check the semaphore counter and proceed when the completion condition is met, without requiring external interrupt service from the OS, thereby eliminating the throughput constraint imposed by interrupt handling overhead.