Data processing apparatus, program, recording medium, and content playback apparatus

• US 20070061600A1
• Filed: 08/31/2006
• Published: 03/15/2007
• Est. Priority Date: 08/31/2005
• Status: Active Grant

• Current Assignee: Socionext Inc.
• Original Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Inventors: Kuroda, Manabu, Furuya, Osamu
• Granted Patent: US 7,584,312 B2
• Time in Patent Office: Days
• US Class Current: 713/300
• CPC Class Codes: G06F 1/3203 Power management, i.e. event-based initiation of a power-saving mode
• CPC Class Codes: G06F 1/3246 by software initiated power-off

Abstract

A data processing apparatus stops a supply of data to a buffer when the buffer becomes full, and thereafter performs processing such as moving to a low-power mode and switching execution tasks. The data processing apparatus then reverts from the low-power mode and resumes execution of a task for supplying data to the buffer when a predetermined reversion condition is satisfied. The predetermined reversion condition is that, for example, processing with respect to data in a predetermined data cluster is completed, a predetermined time period has elapsed, or a cycle handler notifies an event occurrence.

Claims

1. A data processing apparatus comprising:

a buffer;

a data supply unit operable to supply data to the buffer;

a processing execution unit operable to read the data from the buffer and execute processing;

a buffer management unit operable to manage a stored data amount of the buffer;

a supply control unit having a normal mode and a low-power mode as operation modes, and operable to

during the normal mode, control the data supply unit to supply the data to the buffer, according to the stored data amount of the buffer, and

restrict the control during the low-power mode; and

a power control unit operable to

move the supply control unit from the normal mode to the low-power mode when the stored data amount of the buffer reaches a predetermined threshold, and

after performing the move, revert the supply control unit from the low-power mode to the normal mode when a predetermined reversion condition is satisfied.

2. The data processing apparatus of claim 1, wherein

the predetermined reversion condition is that the processing execution unit executes processing with respect to data in a predetermined data cluster.

3. The data processing apparatus of claim 2, further comprising:

a target performance management unit operable to manage a processing capacity to be achieved by the processing execution unit, and control an amount of the data in the predetermined data cluster according to the processing capacity.

4. The data processing apparatus of claim 1, wherein

the buffer management unit includes a lower-limit detection subunit operable to detect that the stored data amount of the buffer is less than or equal to a predetermined lower threshold, and

the predetermined reversion condition is that the lower-limit detection subunit performs the detection after the power control unit has performed the move.

5. The data processing apparatus of claim 4, further comprising:

a target performance management unit operable to manage a processing capacity to be achieved by the processing execution unit, and control a value of the predetermined lower threshold according to the processing capacity.

6. The data processing apparatus of claim 1, wherein

the predetermined reversion condition is that a predetermined time period has elapsed after the power control unit has performed the move.

7. The data processing apparatus of claim 6, further comprising:

a target performance management unit operable to manage a processing capacity to be achieved by the processing execution unit, and control a value of the predetermined time period according to the processing capacity.

8. The data processing apparatus of claim 1, further comprising:

a cyclic event occurrence unit operable to notify an event occurrence at a predetermined cycle, wherein

the predetermined reversion condition is that the cyclic event occurrence unit notifies the event occurrence after the power control unit has performed the move.

9. The data processing apparatus of claim 8, further comprising:

a target performance management unit operable to manage a processing capacity to be achieved by the processing execution unit, and control a length of the predetermined cycle according to the processing capacity.

10. The data processing apparatus of claim 1, wherein

the supply control unit has a plurality of the low-power modes, each having a different power consumption,

the data processing apparatus further comprises a target performance management unit operable to manage a processing capacity to be achieved by the processing execution unit, and

the power control unit includes a selection subunit operable to select one of the plurality of low-power modes according to the processing capacity, and moves the supply control unit to the low-power mode selected by the selection subunit.

11. A data processing apparatus comprising:

a buffer;

a processing execution unit operable to read data from the buffer and execute processing;

a buffer management unit operable to manage a stored data amount of the buffer;

a task execution unit operable to execute one or more tasks including a data supply control task for controlling, according to the stored data amount of the buffer, processing for supplying the data to the buffer; and

a task execution right control unit operable to

stop execution of the data supply control task when the stored data amount of the buffer reaches a predetermined threshold while the data supply control task has been allocated a task execution right in the task execution unit, and

after performing the stopping, control allocation of the task execution right such that the execution of the data supply control task is resumed when a predetermined resumption condition is satisfied.

12. The data processing apparatus of claim 11, wherein

the task execution right control unit

along with stopping the execution of the data supply control task, transfers the task execution right that was allocated to the data supply control task to a simultaneous task for performing processing other than for supplying the data to the buffer, and

after performing the stopping, controls the allocation of the task execution right by allocating the task execution right to the data supply control task when the predetermined resumption condition is satisfied.

13. The data processing apparatus of claim 12, being able to operate in a plurality of operation modes having respectively differing power consumptions, and further comprising:

a normal mode and a low-power mode as the operation modes; and

a power control unit operable to

move the data processing apparatus from the normal mode to the low-power mode when none of the one or more tasks to be executed are present in the task execution unit or all of the one or more tasks are in an execution wait state after the task execution right control unit has performed the transfer, and

after performing the move, revert the data processing apparatus from the low-power mode to the normal mode when the predetermined resumption condition is satisfied.

14. The data processing apparatus of claim 13, wherein

the predetermined resumption condition is that any of the one or more tasks becomes executable after the power control unit has performed the move.

15. The data processing apparatus of claim 13, further comprising:

a plurality of the low-power modes, each having a different power consumption; and

a target performance management unit operable to manage a processing capacity to be achieved by the processing execution unit, wherein

the power control unit includes a selection subunit operable to select one of the plurality of low-power modes according to the processing capacity, and

the power control unit moves the data processing apparatus to the low-power mode selected by the selection subunit.

16. The data processing apparatus of claim 11, being able to operate in a plurality of operation modes having respectively differing power consumptions, and further comprising a normal mode and a low-power mode as the operation modes, wherein

the task execution unit allocates the task execution right to the one or more tasks, and executes the one or more tasks by a round-robin method, and

the data processing apparatus further comprises a power control unit operable to cause the data processing apparatus to operate in the low-power mode in a time slot of the data supply control task while the execution thereof has been stopped by the task execution right control unit.

17. The data processing apparatus of claim 16, further comprising:

a plurality of the low-power modes, each having a different power consumption; and

a target performance management unit operable to manage a processing capacity to be achieved by the processing execution unit, wherein

the power control unit includes a selection subunit operable to select one of the plurality of low-power modes according to the processing capacity, and

the power control unit causes the data processing apparatus to operate in the low-power mode selected by the selection subunit, in the time slot.

18. The data processing apparatus of claim 11, wherein

the predetermined resumption condition is that the processing execution unit executes processing with respect to data in a predetermined data cluster.

19. The data processing apparatus of claim 18, further comprising:

a target performance management unit operable to manage a processing capacity to be achieved by the processing execution unit, and control an amount of the data in the predetermined data cluster according to the processing capacity.

20. The data processing apparatus of claim 11, wherein

the buffer management unit includes a lower-limit detection subunit operable to detect that the stored data amount of the buffer is below a predetermined lower threshold, and

the predetermined resumption condition is that the lower-limit detection subunit performs the detection after the task execution right control unit has performed the stopping.

21. The data processing apparatus of claim 20, further comprising:

a target performance management unit operable to manage a processing capacity to be achieved by the processing execution unit, and control a value of the predetermined lower threshold according to the processing capacity.

22. The data processing apparatus of claim 11, wherein

the predetermined resumption condition is that a predetermined time period has elapsed after the task execution right control unit has performed the stopping.

23. The data processing apparatus of claim 22, further comprising:

a target performance management unit operable to manage a processing capacity to be achieved by the processing execution unit, and control a value of the predetermined time period according to the processing capacity.

24. The data processing apparatus of claim 11, further comprising a cyclic event occurrence unit operable to notify an event occurrence at a predetermined cycle, wherein

the predetermined resumption condition is that the cyclic event occurrence unit notifies the event occurrence after the task execution right control unit has performed the stopping.

25. The data processing apparatus of claim 24, further comprising:

a target performance management unit operable to manage a processing capacity to be achieved by the processing execution unit, and control a length of the predetermined cycle according to the processing capacity.

26. A content playback apparatus for sequentially reading data of digital content that is recorded on a recording medium and is playable by performing predetermined decoding processing, and for playing back the read data, the content playback apparatus comprising:

a buffer;

a data supply unit operable to sequentially read the data of the digital content from the recording medium, and supply the read data to the buffer;

a decoder operable to sequentially read the data from the buffer, and decode the read data;

a playback processing unit operable to playback the decoded data;

a remaining amount observing unit operable to manage a stored data amount of the buffer;

a data supply control unit having a normal mode and a low-power mode as operation modes, and operable to

during the normal mode, control the supply of the data to the buffer, according to whether the stored data amount of the buffer has reached a predetermined threshold, and

restrict functions for the control while operating in the low-power mode; and

a data supply control mode control unit operable to

move the data supply control unit from the normal mode to the low-power mode when the stored data amount of the buffer reaches a predetermined threshold, and

after performing the move, revert the data supply control unit from the low-power mode to the normal mode when a predetermined reversion condition is satisfied.

27. A computer-readable control program for supplying data to a buffer included in a data processing apparatus that can operate in a normal mode and a low-power mode as operation modes, and when operating in the low-power mode restricts processing for controlling a supply of data to the buffer according to a stored data amount of the buffer, and for causing the data processing apparatus to execute processing using the data supplied to the buffer, the control program comprising:

a processing execution step of reading the data from the buffer and executing processing;

a buffer management step of managing the stored data amount of the buffer;

a supply control step of controlling the supply of data to the buffer according to the stored data amount of the buffer; and

a power control step of moving the data processing apparatus from the normal mode to the low-power mode when the stored data amount of the buffer reaches a predetermined threshold, and after performing the move, reverting the data processing apparatus from the low-power mode to the normal mode when a predetermined reversion condition is satisfied.

28. A recording medium having recorded thereon a computer-readable control program for supplying data to a buffer included in a data processing apparatus that can operate in a normal mode and a low-power mode as operation modes, and when operating in the low-power mode restricts processing for controlling a supply of data to the buffer according to a stored data amount of the buffer, and for causing the data processing apparatus to execute processing using the data supplied to the buffer, the control program comprising:

a processing execution step of reading the data from the buffer and executing processing;

a buffer management step of managing the stored data amount of the buffer;

a supply control step of controlling the supply of data to the buffer according to the stored data amount of the buffer; and

a power control step of moving the data processing apparatus from the normal mode to the low-power mode when the stored data amount of the buffer reaches a predetermined threshold, and after performing the move, reverting the data processing apparatus from the low-power mode to the normal mode when a predetermined reversion condition is satisfied.

29. A computer-readable control-program for supplying data to a buffer included in a data processing apparatus, and causing the data processing apparatus to execute processing using the data supplied to the buffer, the control program comprising:

a processing execution step of reading data from the buffer and executing processing;

a buffer management step of managing a stored data amount of the buffer;

a task execution step of executing one or more tasks including a data supply control task for controlling, according to the stored data amount of the buffer, processing for supplying the data to the buffer; and

a task execution right control step of

stopping execution of the data supply control task when the stored data amount of the buffer reaches a predetermined threshold while the data supply control task has been allocated a task execution right in the task execution step, and

after performing the stopping, controlling allocation of the task execution right such that the execution of the data supply control task is resumed when a predetermined resumption condition is satisfied.

30. A recording medium having recorded thereon a computer-readable control program for supplying data to a buffer included in a data processing apparatus, and causing the data processing apparatus to execute processing using the data supplied to the buffer, the control program comprising:

a processing execution step of reading data from the buffer and executing processing;

a buffer management step of managing a stored data amount of the buffer;

a task execution step of executing one or more tasks including a data supply control task for controlling, according to the stored data amount of the buffer, processing for supplying the data to the buffer; and

a task execution right control step of

stopping execution of the data supply control task when the stored data amount of the buffer reaches a predetermined threshold while the data supply control task has been allocated a task execution right in the task execution step, and

after performing the stopping, controlling allocation of the task execution right such that the execution of the data supply control task is resumed when a predetermined resumption condition is satisfied.