FLEXIBLE AND EXTENSIBLE RECEIVE SIDE SCALING

• US 20120189013A1
• Filed: 04/03/2012
• Published: 07/26/2012
• Est. Priority Date: 06/28/2006
• Status: Active Grant

• Current Assignee: Linden Cornett, Stephen D. Goglin
• Original Assignee: Linden Cornett, Stephen D. Goglin
• Inventors: Goglin, Stephen D., Cornett, Linden
• Granted Patent: US 8,874,767 B2
• Time in Patent Office: Days
• US Class Current: 370/395.32
• CPC Class Codes: H04L 12/56 Packet switching systems
• CPC Class Codes: H04L 45/745 Address table lookup; Address filtering
• CPC Class Codes: H04L 47/10 Flow control; Congestion control

Abstract

In an embodiment, a method is provided. The method of this embodiment provides in response to receiving a packet, looking up a packet characteristic in one of at least one protocol table to determine one or more fields of the packet to use as a hash value, applying a hash function to the hash value to obtain a hash result, and using the hash result to determine one of a plurality of processors on which to process the packet.

Claims

1. A method comprising:

in response to receiving a packet, looking up a packet characteristic in one of at least one protocol table to determine one or more fields of the packet to use as a hash value;

applying a hash function to the hash value to obtain a hash result; and

using the hash result to determine one of a plurality of processors on which to process the packet.

2. The method of claim 1, wherein said looking up a packet characteristic in one of at least one protocol table to determine one or more fields of the packet to use as a hash value comprises:

obtaining an offset and a mask corresponding to the packet characteristic; and

applying the mask to the packet at a start bit of the packet plus the offset.

3. The method of claim 2, wherein the packet characteristic comprises a protocol.

4. The method of claim 2, wherein the packet characteristic comprises a port identifier.

5. The method of claim 1, wherein said looking up a packet characteristic in one of at least one protocol table to determine one or more fields of the packet to use as a hash value comprises:

performing the following until there are no further layers to reveal;

revealing a next layer to expose a protocol; and

if the exposed protocol is a supported protocol, obtaining one or more default fields of the packet;

setting the revealed next layer to the last revealed protocol;

looking up the packet characteristic corresponding to the last revealed layer in one of the at least one protocol table to obtain an offset and a mask; and

if the packet characteristic is found, applying the offset and the mask to the packet.

6. The method of claim 5, additionally comprising if the packet characteristic is not found in the one of at least one protocol table, then using the one or more default fields as the hash value.

7. The method of claim 6, wherein if there are no default fields, sending the packet to a default one of the plurality of processors.

8. The method of claim 6, wherein the one or more default fields are specified by Microsoft®

RSS (Receive Side Scaling).

9. A system comprising one or more storage mediums having stored thereon, individually or in combination, instructions that when executed by one or more processors, results in the following:

in response to receiving a packet, looking up a packet characteristic in one of at least one protocol table to determine one or more fields of the packet to use as a hash value;

applying a hash function to the hash value to obtain a hash result; and

using the hash result to determine one of a plurality of processors on which to process the packet.

10. The system of claim 9, wherein said looking up a packet characteristic in one of at least one protocol table to determine one or more fields of the packet to use as a hash value comprises:

obtaining an offset and a mask corresponding to the packet characteristic; and

applying the mask to the packet at a start bit of the packet plus the offset.

11. The system of claim 10, wherein the packet characteristic comprises a protocol.

12. The system of claim 10, wherein the packet characteristic comprises a port identifier.

13. The system of claim 9, wherein said looking up a packet characteristic in one of at least one protocol table to determine one or more fields of the packet to use as a hash value comprises:

performing the following until there are no further layers to reveal;

revealing a next layer to expose a protocol; and

if the exposed protocol is a supported protocol, obtaining one or more default fields of the packet;

setting the revealed next layer to the last revealed protocol;

looking up the packet characteristic corresponding to the last revealed layer in one of the at least one protocol table to obtain an offset and a mask; and

if the packet characteristic is found, applying the offset and the mask to the packet.

14. The system of claim 13, wherein the instructions that when executed by one or more processors results in the following additional operations comprising:

if the packet characteristic is not found in the one of at least one protocol table, then using the one or more default fields as the hash value.

15. The system of claim 14, wherein if there are no default fields, sending the packet to a default one of the plurality of processors.

16. The system of claim 14, wherein the one or more default fields are specified by Microsoft®

RSS (Receive Side Scaling).

17. A computer implemented method comprising:

receiving a packet at a network controller; and

determining which of a plurality of processors to select for processing the packet using a hash result that is obtained by applying a hash function with a hash value to a field of the packet, wherein the field of the packet is determined by looking up in at least one protocol table stored in computer readable memory.

18. The method of claim 17, wherein the field of the packet to use as a hash value is determined by looking up a packet characteristic in at least one protocol table stored in computer readable memory.

19. The method of claim 18, wherein said looking up a packet characteristic in one of at least one protocol table comprises:

obtaining an offset and a mask corresponding to the packet characteristic; and

applying the mask to the packet at a start bit of the packet plus the offset.

20. The method of claim 19, wherein said looking up a packet characteristic in one of at least one protocol table comprises:

performing the following until there are no further layers to reveal;

revealing a next layer to expose a protocol; and

if the exposed protocol is a supported protocol, obtaining one or more default fields of the packet;

setting the revealed next layer to the last revealed protocol;

looking up the packet characteristic corresponding to the last revealed layer in one of the at least one protocol table to obtain an offset and a mask; and

if the packet characteristic is found, applying the offset and the mask to the packet.