Directed route load/store packets for distributed switch initialization

• US 9,282,036 B2
• Filed: 02/20/2013
• Issued: 03/08/2016
• Est. Priority Date: 02/20/2013
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Flynn, William T., Kirscht, Joseph A., Walk, Bruce M.
• Primary Examiner(s): Orgad, Edan
• Assistant Examiner(s): Shah, Saumit
• Application Number:
  US13/772,018
• Publication Number:
  US 20140233579A1
• Time in Patent Office: 1,112 Days
• Field of Search: 370/225, 370/290, 370/380, 370/386, 370/390, 370/392, 370/393, 370/396, 370/400, 370/401, 709/230, 709/233
• US Class Current: 1/1
• CPC Class Codes: H04L 45/34 Source routing
• CPC Class Codes: H04L 45/44 Distributed routing
• CPC Class Codes: H04L 45/566 Routing instructions carried by the data packet, e.g. active networks
• CPC Class Codes: H04L 45/66 Layer 2 routing, e.g. in Ethernet based MAN's
• CPC Class Codes: H04L 45/72 Routing based on the source address

Abstract

Techniques are described for transmitting a packet from a source switch module to a destination switch module. Embodiments receive, at the source switch module, from the destination switch module, path information specifying a path from the source switch module to the destination switch module. Upon detecting an occurrence of a predefined event, a packet is generated that includes (i) the received path information and (ii) payload data to be processed at the destination switch module. Embodiments determine an Ethernet port of the source switch module on which to transmit the packet, based on the received path information. The packet is transmitted to a second switch module using the determined Ethernet port.

Claims

1. A method of transmitting a packet from a source switch module to a destination switch module, comprising:

receiving, at the source switch module, from the destination switch module, an ordered listing of Ethernet link identifies specifying a path for transmitting packets from the source switch module to the destination switch module;

upon detecting an occurrence of a predefined event, generating a packet that includes (i) the received ordered listing of Ethernet link identifiers, (ii) a second ordered listing of Ethernet link identifiers, specifying a return path for transmitting data packets from the destination switch module to the source switch module, and (iii) a set of load/store operations to be executed by the destination switch module, wherein an intermediary switch module along the path from the source switch module to the destination switch module is configured to modify the packet by inserting an Ethernet link identifier into the second portion of the packet, the Ethernet link identifier corresponding to a determined incoming Ethernet port on which the intermediary switch module received the packet;

determining an Ethernet port of the source switch module on which to transmit the packet, by selecting one of the ordered listing of Ethernet link identifiers;

transmitting the packet towards the destination switch module using the determined Ethernet port, wherein the destination switch module is configured to copy the set of load/store operations into an execution buffer for automatic execution; and

once the set of load/store operations have been executed by the destination switch module, receiving, at the source switch module, from the destination switch module, a response packet that includes (i) the second ordered listing of Ethernet link identifiers specifying the return path from the destination switch module to the source switch module and (ii) payload data to be processed at the source switch module.

2. The method of claim 1, wherein the packet includes a hop counter value, configured to be incremented at each hop along the path from the source switch module to the destination switch module.

3. The method of claim 2, wherein the hop counter value is used as an index in selecting one of the Ethernet link identifiers from the ordered listing of Ethernet link identifiers.

4. The method of claim 3, further comprising:

incrementing the hop counter value within the packet, before transmitting the packet to the second switch module.

5. The method of claim 1, wherein the payload data comprises an event identifier corresponding to the first event.

6. The method of claim 1, wherein each of the Ethernet link identifiers within the ordered listing of Ethernet link identifiers corresponds to a respective hop along the path from the source switch module to the destination switch module.

7. A non-transitory computer-readable medium containing computer-readable program code that, when executed, performs an operation for transmitting a packet from a source switch module to a destination switch module, comprising:

receiving, at the source switch module, from the destination switch module, an ordered listing of Ethernet link identifies specifying a path for transmitting packets from the source switch module to the destination switch module;

upon detecting an occurrence of a predefined event, generating a packet that includes (i) the received ordered listing of Ethernet link identifiers, (ii) a second ordered listing of Ethernet link identifiers, specifying a return path for transmitting data packets from the destination switch module to the source switch module, and (iii) a set of load/store operations to be executed by the destination switch module, wherein an intermediary switch module along the path from the source switch module to the destination switch module is configured to modify the packet by inserting an Ethernet link identifier into the second portion of the packet, the Ethernet link identifier corresponding to a determined incoming Ethernet port on which the intermediary switch module received the packet;

determining an Ethernet port of the source switch module on which to transmit the packet, by selecting one of the ordered listing of Ethernet link identifiers;

transmitting the packet towards the destination switch module using the determined Ethernet port, wherein the destination switch module is configured to copy the set of load/store operations into an execution buffer for automatic execution; and

once the set of load/store operations have been executed by the destination switch module, receiving, at the source switch module, from the destination switch module, a response packet that includes (i) the second ordered listing of Ethernet link identifiers specifying the return path from the destination switch module to the source switch module and (ii) payload data to be processed at the source switch module.

8. The non-transitory computer-readable medium of claim 7, wherein the packet includes a hop counter value, configured to be incremented at each hop along the path from the source switch module to the destination switch module.

9. The non-transitory computer-readable medium of claim 8, wherein determining the Ethernet port of the source switch module further comprises:

selecting an Ethernet link identifier from an ordered listing of link identifiers, using the hop counter value as an index.

10. The non-transitory computer-readable medium of claim 9, the operation further comprising:

incrementing the hop counter value within the packet, before transmitting the packet to the second switch module.

11. The non-transitory computer-readable medium of claim 7, wherein the payload data comprises an event identifier corresponding to the first event.

12. The non-transitory computer-readable medium of claim 7, wherein each of the Ethernet link identifiers within the ordered listing of Ethernet link identifiers corresponds to a respective hop along the path from the source switch module to the destination switch module.

13. A system, comprising:

a processor; and

a memory containing a program that, when executed by the processor, performs an operation for transmitting a packet from a source switch module to a destination switch module, comprising;

receiving, at the source switch module, from the destination switch module, an ordered listing of Ethernet link identifies specifying a path for transmitting packets from the source switch module to the destination switch module;

upon detecting an occurrence of a predefined event, generating a packet that includes (i) the received ordered listing of Ethernet link identifiers, (ii) a second ordered listing of Ethernet link identifiers, specifying a return path for transmitting data packets from the destination switch module to the source switch module, and (iii) a set of load/store operations to be executed by the destination switch module, wherein an intermediary switch module along the path from the source switch module to the destination switch module is configured to modify the packet by inserting an Ethernet link identifier into the second portion of the packet, the Ethernet link identifier corresponding to a determined incoming Ethernet port on which the intermediary switch module received the packet;

determining an Ethernet port of the source switch module on which to transmit the packet, by selecting one of the ordered listing of Ethernet link identifiers;

transmitting the packet towards the destination switch module using the determined Ethernet port, wherein the destination switch module is configured to copy the set of load/store operations into an execution buffer for automatic execution; and

once the set of load/store operations have been executed by the destination switch module, receiving, at the source switch module, from the destination switch module, a response packet that includes (i) the second ordered listing of Ethernet link identifiers specifying the return path from the destination switch module to the source switch module and (ii) payload data to be processed at the source switch module.

14. The system of claim 13, wherein the packet includes a hop counter value, configured to be incremented at each hop along the path from the source switch module to the destination switch module.

15. The system of claim 14, wherein determining the Ethernet port of the source switch module further comprises:

selecting an Ethernet link identifier from an ordered listing of link identifiers, using the hop counter value as an index.

16. The system of claim 15, the operation further comprising:

incrementing the hop counter value within the packet, before transmitting the packet to the second switch module.

17. The system of claim 13, wherein the payload data comprises an event identifier corresponding to the first event.

18. The system of claim 13, wherein each of the Ethernet link identifiers within the ordered listing of Ethernet link identifiers corresponds to a respective hop along the path from the source switch module to the destination switch module.