Bootstrap processor election mechanism on multiple cluster bus system

• US 6,611,911 B1
• Filed: 12/30/1999
• Issued: 08/26/2003
• Est. Priority Date: 12/30/1999
• Status: Expired due to Term

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Binns, Frank, Aaron, Larry D. Jr., LeClerg, Frank E., Edmonds, Bruce C. Jr., Keating, Craig W., OʼShea, David J.
• Primary Examiner(s): Lee, Thomas
• Assistant Examiner(s): Cao, Chun
• Application Number:
  US09/474,781
• Time in Patent Office: 1,335 Days
• Field of Search: 713/1, 713/2
• US Class Current: 713/1
• CPC Class Codes: G06F 15/177 Initialisation or configuration control processor initialisation G06F9/4405

Abstract

A method of electing a bootstrap processor from among a plurality of processor includes creating an atomic access shared location and electing one of said processors as the bootstrap processor.

Claims

1. A method, comprising:

providing a plurality of processors;

providing a storage location shared by the plurality of processors;

providing atomic access to the shared storage location;

electing one of the processors as a bootstrap processor in accordance with a value stored in the shared storage location;

reading the value of the shared storage location by each of the processors and writing the value of the shared storage location by at least one of the processors;

assigning an initial value to the shared storage location;

after reading the value of the shared storage location by one of the plurality of processors, comparing the read value to the initial value; and

if the read value corresponds to the initial value, electing the one processor as the elected bootstrap processor.

2. The method as recited in claim 1, further comprising writing the value of the shared storage location with a value corresponding to the elected bootstrap processor.

3. A method, comprising:

providing a plurality of processors;

providing a storage location shared by the plurality of processors;

providing atomic access to the shared storage location;

electing one of the processors as a bootstrap processor in accordance with a value stored in the shared storage location;

reading the value of the shared storage location by each of the processors and writing the value of the shared storage location by at least one of the processors;

assigning a unique identification to each of the processors, and wherein the writing comprises one of the processors writing the value of the shared storage location with a value corresponding to the unique identification of the processor, the method further comprising;

reading the value of the shared storage location;

comparing the read value to the value corresponding to the unique identification of the processor; and

if the comparison is favorable, electing the processor as the elected bootstrap processor.

4. The method as recited in claim 3, further comprising ignoring further writing of the shared storage location after the elected bootstrap processor is elected.

5. A system, comprising:

a plurality of processors; and

a storage location shared by the plurality of processors,

wherein each processor is adapted to wait a different period of time during boot to access the shared storage location, and wherein one of the processors is elected as a bootstrap processor in accordance with a value stored in the shared storage location, wherein an initial value is assigned to the shared storage location and wherein each processor is adapted to;

read the value stored in the shared storage location;

compare the read value to the initial value; and

take the role of the elected bootstrap processor if the read value corresponds to the initial value.

6. The system as recited in claim 5, wherein each processor is further adapted to write the value of the shared storage location with a value corresponding to the elected bootstrap processor if the read value corresponds to the initial value.

7. A system, comprising:

a plurality of processors; and

a storage location shared by the plurality of processors,

wherein each processor is adapted to wait a different period of time during boot to access the shared storage location, and wherein one of the processors is elected as a bootstrap processor in accordance with a value stored in the shared storage location, wherein a unique identification is assigned to each of the processors, and wherein each processor is adapted to;

write the value of the shared storage location with a value corresponding to the unique identification of the processor;

reading the value of the shared storage location;

compare the read value to the unique identification of the processor; and

take the role of the elected bootstrap processor if the read value corresponds to the unique identification of the processor.

8. The system as recited in claim 7, wherein the shared storage location is adapted to accept the first write operation thereon and to ignore further write operations.