PACKET STEERING

• US 20130114599A1
• Filed: 11/08/2011
• Published: 05/09/2013
• Est. Priority Date: 11/08/2011
• Status: Active Grant

• Current Assignee: Mellanox Technologies Limited (NVIDIA Corporation)
• Original Assignee: Mellanox Technologies Limited (NVIDIA Corporation)
• Inventors: Bloch, Noam, Shahar, Ariel, Chapman, Hillel, Arad, Nir Haim, Wated, Amir
• Granted Patent: US 9,397,960 B2
• Time in Patent Office: Days
• US Class Current: 370/392
• CPC Class Codes: H04L 45/38 Flow based routing
• CPC Class Codes: H04L 45/74 Address processing for routing
• CPC Class Codes: H04L 45/745 Address table lookup; Address filtering
• CPC Class Codes: H04L 47/10 Flow control; Congestion control
• CPC Class Codes: H04L 49/351 for local area network [LAN], e.g. Ethernet switches
• CPC Class Codes: H04L 49/355 Application aware switches, e.g. for HTTP
• CPC Class Codes: H04L 49/358 Infiniband Switches
• CPC Class Codes: H04L 49/70 Virtual switches

Abstract

A method for steering packets, including receiving a packet and determining parameters to be used in steering the packet to a specific destination, in one or more initial steering stages, based on one or more packet specific attributes. The method further includes determining an identity of the specific destination of the packet in one or more subsequent steering stages, governed by the parameters determined in the one or more initial stages and one or more packet specific attributes, and forwarding the packet to the determined specific destination.

Claims

1. A method of steering a packet, comprising:

receiving a packet by a packet steering unit;

determining parameters to be used in steering the packet to a specific destination, in one or more initial steering stages, based on one or more packet specific attributes;

determining an identity of the specific destination of the packet in one or more subsequent steering stages, governed by the parameters determined in the one or more initial stages and one or more packet specific attributes; and

forwarding the packet to the determined specific destination.

2. The method of claim 1, wherein determining parameters to be used in steering the packet comprises determining a lookup table used in the one or more subsequent stages.

3. The method of claim 2, wherein determining parameters to be used in steering the packet comprises determining a key to be used in accessing the lookup table in the one or more subsequent stages.

4. The method of claim 1, wherein each of the one or more steering stages includes accessing a lookup table.

5. The method of claim 4, wherein the one or more initial stages and the one or more subsequent stages include together accessing a plurality of different lookup tables.

6. The method of claim 5, wherein the one or more initial and subsequent stages include accessing a plurality of different lookup tables, each corresponding to a respective virtual machine on a computer serviced by the packet steering unit.

7. The method of claim 4, wherein the packet includes an InfiniBand unicast packet.

8. The method of claim 7, and comprising receiving a multicast packet and forwarding the multicast packet based on a lookup to one or more steering tables.

9. The method of claim 1, wherein the packet steering unit handles one or more other packets between at least some pairs of stages.

10. The method of claim 1, wherein the packet specific attributes comprise information in the packet.

11. The method of claim 1, wherein the packet specific attributes comprise information on the packet not included in the packet.

12. The method of claim 1, comprising forwarding the packet to at least one additional destination, based on information from one or more of the stages.

13. The method of claim 12, wherein forwarding the packet to the at least one additional destination comprises forwarding before the one or more subsequent stages.

14. The method of claim 12, wherein forwarding the packet to the at least one additional destination comprises forwarding to a plurality of destinations determined in a single stage.

15. The method of claim 1, wherein in each stage only fields from a single protocol-layer header are used in determining the parameters or the destination identity.

16. The method of claim 1, wherein determining the parameters and the identity of the specific destination of the packet include a first specific total number of stages, and comprising receiving an additional packet and forwarding the additional packet after a second specific total number of stages different from the first specific total number of stages.

17. The method of claim 1, wherein determining the parameters and the identity of the specific destination of the packet include accessing a first specific total number of fields of the packet, and comprising receiving an additional packet and forwarding the additional packet after accessing a second specific total number of fields of the additional packet, different from the first specific total number of fields.

18. The method of claim 1, wherein determining the parameters and the identity of the specific destination of the packet include accessing a specific set of fields of the packet, and comprising receiving an additional packet and forwarding the additional packet after accessing at least one field not included in the specific set.

19. A packet steering unit, comprising:

at least one packet queue in which packets containing information are accumulated;

one or more steering tables configured with entries including instructions for handling corresponding InfiniBand packets responsively to the information contained therein; and

a steering engine configured to identify for each unicast InfiniBand packet in the packet queue, responsively to the information contained in the packet, a corresponding entry of a table of the one or more steering tables and to handle the packet according to the corresponding entry.

20. The packet steering unit of claim 19, wherein at least some of the entries of the one or more steering tables include instructions on a further handling stage to be performed for the corresponding packets.

21. The packet steering unit of claim 19, wherein the steering engine is additionally configured to identify for multicast packets in the packet queue, responsively to the information contained in the packet, a corresponding entry of a table and to handle the packet according to the corresponding entry.

22. The packet steering unit of claim 21, wherein the one or more steering tables comprise a plurality of steering tables.

23. The packet steering unit of claim 22, wherein the plurality of steering tables include at least two tables having entries of different sizes.

24. The packet steering unit of claim 19, wherein the steering engine is additionally configured to identify for non-InfiniBand packets in the packet queue, responsively to the information contained in the packet, a corresponding entry of a table and to handle the packet according to the corresponding entry.

25. A packet steering unit, comprising:

an input interface configured to receive packets for steering;

one or more memory units configured with instructions on fields of packets to be used in determining steering destinations of packets; and

a hardware-logic steering engine configured to determine steering destinations of packets received through the input interface, by examining the fields indicated by the one or more memory units, and accordingly to steer the packets.

26. The packet steering unit of claim 25, wherein the input interface comprises a plurality of ports, and wherein at least one of the ports can receive packets of different protocols according to a port configuration.

27. The packet steering unit of claim 25, wherein the input interface comprises a plurality of ports configured to receive packets in accordance with different protocols and wherein the steering engine is configured to steer packets of the different protocols concurrently.

28. The packet steering unit of claim 25, wherein the one or more memory units are configured with a plurality of steering tables including the instructions on fields of packets to be used in determining steering destinations of packets.

29. The packet steering unit of claim 28, wherein the hardware-logic steering engine is configured to access a plurality of table entries in determining for one or more packets a single destination.

30. The packet steering unit of claim 29, wherein the hardware-logic steering engine is configured to use different packet fields in accessing each of the plurality of table entries.

31. The packet steering unit of claim 29, wherein each table entry includes an instruction on whether an additional lookup stage should be performed for the current packet and the packet fields to be used in the additional lookup stage, if an additional lookup is to be performed.

32. The packet steering unit of claim 29, wherein the hardware-logic steering engine is configured to access different numbers of table entries for different packets.

33. The packet steering unit of claim 29, wherein the hardware-logic steering engine is configured to access entries of a plurality of tables in determining for one or more packets a single destination.

34. The packet steering unit of claim 29, wherein the hardware-logic steering engine is configured to access a plurality of tables having different entry sizes, in determining for one or more packets a single destination.

35. The packet steering unit of claim 25, comprising a memory unit configured with a list of packet field arrangements and wherein the steering engine is configured to determine for each packet handling stage it performs, an entry of the list which determines the fields of the packets to be used in the stage.

36. The packet steering unit of claim 25, wherein the steering unit is configured to handle a plurality of packets concurrently.

37. The packet steering unit of claim 36, wherein the steering unit is configured to be able to examine different fields of packets handled concurrently.

38. A packet steering unit, comprising:

an input interface configured to receive packets for steering;

a packet pool for storing a plurality of packets from the input interface concurrently;

at least one memory unit configured with one or more steering tables having entries including instructions for forwarding corresponding packets and instructions on a further handling stage to be performed for the corresponding packets; and

a hardware-logic steering engine configured to perform handling stages in which the engine determines for a packet in the packet pool a corresponding entry in the at least one memory unit and handles the packet according to the instructions in the corresponding entry,

wherein the steering engine is configured to handle a plurality of packets concurrently, such that at least some first packets are handled between a plurality of handling stages of a single second packet.

39. The packet steering unit of claim 38, wherein the hardware-logic steering engine is configured to avoid beginning handling of a packet belonging to a same stream as an other packet currently being handled, until the handling of the other packet is completed.

40. The packet steering unit of claim 38, wherein the packet pool is configured to store at least 16 packets.

41. The packet steering unit of claim 38, wherein the hardware-logic steering engine is configured to sequentially go through the packets in the packet pool and perform on each packet in the pool a single handling stage each time it is reached sequentially.

42. The packet steering unit of claim 38, wherein the one or more steering tables are configured with instructions such that at least one packet undergoes a plurality of handling stages for determining a single destination of the packet.

43. The packet steering unit of claim 38, wherein the packet pool includes for each packet which previously underwent a handling session, an indication of a set of parameters to be used in handling the packet by the steering engine in a next handling stage.

44. The packet steering unit of claim 38, wherein the one or more steering tables are configured with instructions such that different packets undergo different numbers of handling stages.

45. The packet steering unit of claim 38, wherein the one or more steering tables are configured with instructions such that at least one packet undergoes only a single handling stage.

46. The packet steering unit of claim 38, wherein the one or more steering tables are configured with instructions such that at least one packet undergoes at least three handling stages, in selecting a single destination of the packet.

47. The packet steering unit of claim 38, wherein the one or more steering tables are configured with instructions such that at least one packet undergoes at least five handling stages.

48. The packet steering unit of claim 38, wherein the steering engine is configured to determine for packets a corresponding entry of the table, based on one or more fields of the packet.

49. The packet steering unit of claim 48, wherein the one or more fields of the packet used by the steering engine in any specific handling stage of a packet include fields of only a single protocol layer.

50. The packet steering unit of claim 48, wherein the one or more fields of the packet used by the steering engine in at least one specific handling stage of a packet include fields of a plurality of different protocol layers.

51. The packet steering unit of claim 38, wherein the one or more steering tables comprise a plurality of different steering tables.

52. A packet steering unit, comprising:

at least one packet queue in which packets containing information are accumulated;

one or more steering tables configured with entries including instructions on a destination of corresponding packets or on an additional table entry lookup to be performed for the packet; and

a steering engine configured to access for each packet in the packet queue, responsively to the information contained in the packet, a corresponding table entry and to handle the packet according to the corresponding entry, including, for at least some packets, accessing an additional table entry indicated by the accessed entry.

53. The packet steering unit of claim 52, wherein the one or more steering tables are configured to have the steering engine access entries of a plurality of steering tables in handling at least one of the packets.

54. The packet steering unit of claim 53, wherein the one or more steering tables are configured to have the steering engine access entries of different sizes in handling at least one of the packets.