Information processing apparatus and task execution method

1. An information processing apparatus, comprising:

an overall control unit including:

a main control unit which executes a main process for controlling said apparatus in a unified manner; and

a plurality of sub-control units, including at least one sub-control unit which executes a task assigned by the main control unit during the execution of the main process, as a sub-process; and

an interrupt unit including:

an event detector which detects an event occurrence upon which an interrupt task is executed during the execution of the main process; and

an interrupt notification unit which notifies said overall control unit of interrupt information indicative of the interrupt task according to the detected event,

wherein the interrupt notification unit selects the sub-control unit, which is in a state capable of executing the interrupt task, from among the plurality of sub-control units, and notifies the selected sub-control unit of the interrupt information,

wherein the sub-control unit notified of the interrupt information executes the interrupt task specified by the interrupt information, as a sub-process, and

wherein interrupt processing in the information processing apparatus, from the event detection through completion of the execution of the specified interrupt task by the sub-control unit, occurs without activity by the main control unit in connection with the interrupt processing.

2. An information processing apparatus according to claim 1 , wherein the sub-control unit includes an interrupt information receiving storage unit for temporarily storing said interrupt information,

wherein the interrupt notification unit informs the sub-control unit of said interrupt information in a manner such that the interrupt information is recorded in the interrupt information receiving storage unit in a sub-control unit which is a notifying party, and

wherein the sub-control unit reads out the interrupt information recorded in the interrupt information receiving storage unit and executes said interrupt task specified by said interrupt information, as a sub-process.

3. An information processing apparatus according to claim 1 , further comprising an auxiliary unit which executes a task instructed from said control unit,

wherein the sub-control unit transfers data generated as a result of execution of the assigned task to said auxiliary unit and, based on the transferred data, said auxiliary unit executes a task which forms a sequel to the task executed by the sub-control unit, and thereby the sub-control unit and said auxiliary unit collaborate together to execute a task as a sub-process.

4. An information processing apparatus according to claim 3 , wherein the sub-control unit transfers the generated data to said auxiliary unit by DMA (Direct Memory Access) transfer.

5. A method for executing tasks in an information processing apparatus including a main control unit which executes a main process for controlling said apparatus in a unified manner, a plurality of sub-control units, including at least one sub-control unit which executes a task assigned by the main control unit during the execution of the main process, as a sub-process, and an interrupt notification unit which notifies said information processing apparatus of interrupt information indicative of an interrupt task, the method comprising:

detecting an event occurrence upon which the interrupt task is executed during the execution of the main process;

having the interrupt notification unit select the sub-control unit, which is in a state capable of executing the interrupt task, and notify the sub-control unit of the interrupt information indicative of the interrupt task according to the detected event;

having the sub-control unit notified of the interrupt information execute the interrupt task specified by the interrupt information, as a sub-process, and

conducting interrupt processing in the information processing apparatus, from the event detection through completion of the execution of the specified interrupt task by the sub-control unit, without the main control unit undertaking any activity in connection with the interrupt processing.

6. A recording medium, readable by a computer, which stores a task execution program, executable by a computer, for executing tasks in an information processing apparatus including a main control unit which executes a main process for controlling said apparatus in a unified manner, a plurality of sub-control units, including at least one sub-control unit which executes a task assigned by the main control unit during the execution of the main process, as a sub-process, and an interrupt notification unit which notifies said information processing apparatus of interrupt information indicative of an interrupt task, the program including the functions of:

detecting an event occurrence upon which the interrupt task is executed during the execution of the main process;

having the interrupt notification unit select the sub-control unit, which is in a state capable of executing the interrupt task, and notify the sub-control unit of the interrupt information indicative of the interrupt task according to the detected event;

having the sub-control unit notified of the interrupt information execute the interrupt task specified by the interrupt information, as a sub-process, and

conducting interrupt processing in the information processing apparatus, from the event detection through completion of the execution of the specified interrupt task by the sub-control unit, without the main control unit undertaking any activity in connection with the interrupt processing.