Thread synchronization by transitioning threads to spin lock and sleep state

An apparatus, comprising:

• a processor system having a first processor configured to execute a main thread and a second processor configured to execute a slave thread;
• a memory storing program instructions that when executed by the processor system are configured to:
• obtain an initial work unit at the main thread;
• divide the initial work unit into a first work unit and another work unit;
• send, via a wake-up message, the first work unit from the main thread to the slave thread;
• and
• process the other work unit at the main thread;
• transition the slave thread from a sleep state to a spin-lock state in response to the wake-up message from the main thread;
• transition the slave thread out of the spin-lock state to process the first work unit from the main thread;
• determine, at the main thread, an elapsed time period until receipt of a second work unit for the slave thread before the receipt of the second work unit;
• and
• transition the slave thread to the spin-lock state if the elapsed time period satisfies a threshold time period, or to the sleep state if the elapsed time period does not satisfy the threshold time period.

A non-transitory computer readable medium having instructions stored thereon that when executed by a processor system cause the processor system to perform a method of synchronizing a main thread and a slave thread, comprising:

• obtaining an initial work unit at the main thread;
• dividing the initial work unit into a first work unit and another work unit;
• sending, via a wake-up message, the first work unit from the main thread to the slave thread;
• and
• processing the other work unit at the main thread;
• transitioning the slave thread from a sleep state to a spin-lock state in response to the wake-up message from the main thread;
• transitioning the slave thread out of the spin-lock state to process the first work unit from the main thread;
• determining, at the main thread, an elapsed time period until receipt of a second work unit for the slave thread, wherein the act of determining the elapsed time period is performed before the receipt of the second work unit;
• and
• transitioning the slave thread to the spin-lock state if the elapsed time period satisfies a threshold time period, or to the sleep state if the elapsed time period does not satisfy the threshold time period.