FIFO-based network interface supporting out-of-order processing

• US 6,327,625 B1
• Filed: 11/30/1999
• Issued: 12/04/2001
• Est. Priority Date: 11/30/1999
• Status: Expired due to Term

• Current Assignee: Hewlett Packard Enterprise Development LP (Hewlett-Packard Enterprise Company)
• Original Assignee: 3Com Corporation (HP Inc.)
• Inventors: Wang, Chi-Lie, Yang, Li-Jau, Ho, Ngo Thanh
• Primary Examiner(s): Etienne, Ario
• Application Number:
  US09/451,395
• Time in Patent Office: 735 Days
• Field of Search: 709/235, 709/220, 709/250, 710/52, 710/129
• US Class Current: 709/235
• CPC Class Codes: H04L 47/2441 relying on flow classification, e.g. using integrated services [IntServ]
• CPC Class Codes: H04L 47/34 ensuring sequence integrity, e.g. using sequence numbers
• CPC Class Codes: H04L 47/50 Queue scheduling
• CPC Class Codes: H04L 47/624 Altering the ordering of packets in an individual queue
• CPC Class Codes: H04L 47/6245 Modifications to standard FIFO or LIFO
• CPC Class Codes: H04L 63/0236 Filtering by address, protocol, port number or service, e.g. IP-address or URL

Abstract

Support for priority and IP security packets, and other protocols at the network interface level and in conjunction with FIFO-based packet buffers is provided by allowing out of order processing of certain packets in the FIFO. The optimized character of FIFO for sequential transfer is maintained, while particular types of packets are processed out of order to achieve minimum latency and maximum data security in an intelligent network interface card. A buffer stores data packets in an order of receipt. Logic is included in the network interface to transfer packets out of the buffer according to the order of receipt, and according to the respective packet types so that packets having a particular packet type are transferred out of the order of receipt relative to packets having other packet types.

Claims

1. A computer system, comprising:

a host processor;

a network interface having a first port coupled to the host processor, and second port adapted for at least one of receiving data from and transmitting data to a network;

a buffer coupled to the first and second ports which stores data packets from one of the first and second ports in an order of receipt, said packets identifiable as having respective packet types from a plurality of packet types; and

logic to transfer packets out of the buffer to the other of the first and second ports according to the order of receipt, and according to the respective packet types so that packets having a particular packet type are transferred out of the order of receipt, relative to packets having another packet type.

2. The computer system of claim 1, comprising logic to maintain a list of packets stored in the buffer having the particular packet type, and wherein the logic to transfer packets is responsive to the list.

3. The computer system of claim 1, comprising logic to set parameters associated with the packets in the buffer having the particular packet type, and the logic to transfer packets is responsive to the parameters.

4. The computer system of claim 1, wherein the particular type of packet comprises a priority packet.

5. The computer system of claim 1, wherein the particular type of packet comprises a packet suitable for processing with a security protocol.

6. The computer system of claim 1, wherein the logic to transfer the packets includes processing resources which write a control field in the buffer in association with each packet, indicating the type of packet, whether the packet is ready for transfer, and whether the packet has already been transferred.

7. A computer system, comprising:

a host processor;

a network interface having a first port coupled to the host processor, and second port adapted for at least one of receiving data from and transmitting data to a network;

a buffer coupled to the first and second ports which stores data packets from one of the first and second ports in an order of receipt, said packets identifiable as having respective packet types from a plurality of packet types;

logic to transfer packets out of the buffer to the other of the first and second ports according to the order of receipt, and according to the respective packet types so that packets having a particular packet type are transferred out of the order of receipt, relative to packets having another packet type; and

a data filter coupled with the buffer to generate identifiers which identify packets of data stored in the buffer as members of one of a plurality of packet types.

8. A computer system, comprising:

a host processor;

a network interface having a first port coupled to the host processor, and second port adapted for at least one of receiving data from and transmitting data to a network;

a buffer coupled to the first and second ports which stores data packets from one of the first and second ports in an order of receipt, said packets identifiable as having respective packet types from a plurality of packet types;

logic to transfer packets out of the buffer to the other of the first and second ports according to the order of receipt, and according to the respective packet types so that packets having a particular packet type are transferred out of the order of receipt, relative to packets having another packet type;

a data filter coupled with the buffer to generate identifiers which identify packets of data as members of one of a plurality of packet types when the packets are stored in the buffer; and

logic to write the identifiers in the buffer.

9. A computer system, comprising:

a host processor;

a network interface having a first port coupled to the host processor, and second port adapted for at least one of receiving data from and transmitting data to a network;

a buffer coupled to the first and second ports which stores data packets from one of the first and second ports in an order of receipt, said packets identifiable as having respective packet types from a plurality of packet types; and

logic to transfer packets out of the buffer to the other of the first and second ports according to the order of receipt, and according to the respective packet types so that packets having a particular packet type are transferred out of the order of receipt, relative to packets having another packet type;

wherein the particular type of packet comprises a payload suitable for processing according to a particular process prior to transfer, and the network interface includes logic, responsive to the particular packet type, to process the payload according to the particular process and generate control data associated with the particular packet indicating a state of the processing, and the logic to transfer the packet is responsive to the control data so that the particular packet may be transferred out of the order of receipt relative to other packets having other packet types and other packets having the particular packet type based on the control data.

10. A computer system, comprising:

a host processor;

a network interface having a first port coupled to the host processor, and second port adapted for at least one of receiving data from and transmitting data to a network;

a buffer coupled to the first and second ports which stores data packets from one of the first and second ports in an order of receipt, said packets identifiable as having respective packet types from a plurality of packet types; and

logic to transfer packets out of the buffer to the other of the first and second ports according to the order of receipt, and according to the respective packet types so that packets having a particular packet type are transferred out of the order of receipt, relative to packets having another packet type;

wherein the particular process comprises a security protocol compliant with IPsec.

11. A computer system, comprising:

a host processor;

a network interface having a first port coupled to the host processor, and second port adapted for at least one of receiving data from and transmitting data to a network;

a buffer coupled to the first and second ports which stores data packets from one of the first and second ports in an order of receipt, said packets identifiable as having respective packet types from a plurality of packet types; and

logic to transfer packets out of the buffer to the other of the first and second ports according to the order of receipt, and according to the respective packet types so that packets having a particular packet type are transferred out of the order of receipt, relative to packets having another packet type;

wherein the logic to transfer the packets includes processing resources which

set up a control field for each packet stored in the buffer;

write parameters in the control field indicating the packet type, and whether the packet has already been transferred;

maintain a queue of entries identifying packets having the particular packet type;

maintain an indicator of fullness of the buffer; and

transfer a packet from the buffer according to a priority rule which

causes transfer of a packet identified by an entry in the queue out of the order of receipt, and

causes transfer of a packet not identified by an entry in the queue in the order of receipt of the packet, if the parameters in the control field indicate the packet has not already been transferred, and the queue of entries is empty or the indicator of fullness exceeds a threshold.

12. A computer system, comprising:

a host processor;

a network interface having a first port coupled to the host processor, and second port adapted for at least one of receiving data from and transmitting data to a network;

a buffer coupled to the first and second ports which stores data packets from one of the first and second ports in an order of receipt, said packets identifiable as having respective packet types from a plurality of packet types; and

logic to transfer packets out of the buffer to the other of the first and second ports according to the order of receipt, and according to the respective packet types so that packets having a particular packet type are transferred out of the order of receipt, relative to packets having another packet type;

wherein the logic to transfer the packets includes processing resources which

set up a control field for each packet stored in the buffer;

write a parameter in the control field indicating the packet type;

process packets having the particular packet type according to a particular process;

write a parameter in the control field indicating whether the processing according to the particular process is complete; and

transfer a packet from the buffer according to a priority rule which

skips transfer of a packet having the particular packet type if the parameter in the control field indicates the processing is not complete, and

causes transfer of a packet in the order of receipt, if parameters in the control field indicates the packet is ready for transfer.

13. A computer system, comprising:

a host processor;

a network interface having a first port coupled to the host processor, and second port adapted for at least one of receiving data from and transmitting data to a network;

a buffer coupled to the first and second ports which stores data packets from one of the first and second ports in an order of receipt, said packets identifiable as having respective packet types from a plurality of packet types; and

logic to transfer packets out of the buffer to the other of the first and second ports according to the order of receipt, and according to the respective packet types so that packets having a particular packet type are transferred out of the order of receipt, relative to packets having another packet type;

wherein the plurality of packet types includes first and second packet types in addition to the particular packet type, and the logic to transfer the packets includes processing resources which

set up a control field for each packet stored in the buffer;

write parameters in the control field indicating the packet type, and whether the packet has already been transferred;

maintain a queue of entries identifying packets having the particular packet type;

process packets having the second packet type according to a particular process;

write a parameter in the control field for packets having the second packet type indicating whether the processing according to the particular process is complete;

maintain an indicator of fullness of the buffer; and

transfer a packet from the buffer according to a priority rule which

causes transfer of a packet identified by an entry in the queue ahead of packets in the buffer having the first and second packet types relative to the order of receipt,

causes transfer of a packet having the first packet type in the order of receipt, if the parameters in the control field indicate the packet is ready for transfer, and the queue of entries is empty or the indicator of fullness exceeds a threshold, and

causes transfer of a packet having the second packet type after packets having the first packet type relative to the order of receipt if the parameter in the control field indicates the processing is not complete.

14. The computer system of claim 13, wherein the particular type of packet comprises a priority packet, and the second type of packet comprises a packet suitable for processing with a security protocol.

15. A method for managing transfer of data packets between a host processor and a network, comprising:

storing packets in a first-in-first-out buffer in an order of receipt;

identifying packets as having respective packet types from a plurality of packet types; and

transferring packets out of the first-in-a first-out buffer according to the order of receipt, and according to the packet type so that packets having a particular packet type are transferred out of the order of receipt relative to packets having another packet type.

16. The method of claim 15, wherein the particular type of packet comprises a priority packet.

17. The method of claim 15, wherein the particular type of packet comprises a packet suitable for processing with a security protocol.

18. A method for managing transfer of data packets between a host processor and a network, comprising:

storing packets in a first-in-first-out buffer in an order of receipt;

identifying packets as having respective packet types from a plurality of packet types;

transferring packets out of the first-in-a first-out buffer according to the order of receipt, and according to the packet type so that packets having a particular packet type are transferred out of the order of receipt relative to packets having another packet type;

setting up a control field for each packet stored in the buffer;

writing a parameter in the control field indicating the packet type;

processing packets having the particular packet type according to a particular process;

writing a parameter in the control field indicating whether the processing according to the particular process is complete; and

transferring a packet from the buffer according to a priority rule which skips transferring of a packet having the particular type if the parameter in the control field indicates the process is not complete.

19. A method for managing transfer of data packets between a host processor and a network, comprising:

storing packets in a first-in-first-out buffer in an order of receipt;

identifying packets as having respective packet types from a plurality of packet types; and

transferring packets out of the first-in-a first-out buffer according to the order of receipt, and according to the packet type so that packets having a particular packet type are transferred out of the order of receipt relative to packets having another packet type;

wherein the plurality of packet types includes first and second packet types in addition to the particular packet type, and including;

setting up a control field for each packet stored in the buffer indicating an order of receipt;

writing parameters in the control field indicating the packet type, and whether the packet has already been transferred;

maintaining a queue of entries identifying packets having the particular packet type;

processing packets having the second packet type according to a particular process;

writing a parameter in the control field for packets having the second packet type indicating whether the processing according to the particular process is complete;

maintaining an indicator of fullness of the buffer; and

transferring a packet from the buffer according to a priority rule which

causes transferring of a packet identified by an entry in the queue ahead of packets in the buffer having the first and second packet types relative to the order of receipt,

causes transferring of a packet having the first packet type in the order of receipt the packet, if the parameters in the control field indicate the packet has not already been transferred, and the queue of entries is empty or the indicator of fullness exceeds a threshold, and

skips transferring of a packet having the second packet type if the parameter in the control field indicates the processing is not complete.

20. The method of claim 19, wherein the particular type of packet comprises a priority packet, and the second type of packet comprises a packet suitable for processing with a security protocol.

21. A method for managing transfer of data packets between a host processor and a network, comprising:

storing packets in a first-in-first-out buffer in an order of receipt;

identifying packets as having respective packets types from a plurality of packets types;

transferring packets out of the first-in-first-out buffer according to the order of receipt, and according to the packet type so that packets having a particular packet type are transferred out of the order of receipt relative to packets having another packet type; and

storing control parameters associated with packets in the first-in-first-out buffer, the control parameters indicating the packet type, whether the packet is ready for transfer, and whether the packet has already been transferred.

22. A method for managing transfer of data packets between a host processor and a network, comprising:

storing packets in a first-in-first-out buffer in an order of receipt;

identifying packets as having respective packet types from a plurality of packet types;

transferring packets out of the first-in-a first-out buffer according to the order of receipt, and according to the packet type so that packets having a particular packet type are transferred out of the order of receipt relative to packets having another packet type;

setting up a control field for each packet stored in the buffer;

writing parameters in the control field indicating the packet type, and whether the packet has already been transferred;

maintaining a queue of entries identifying packets having the particular packet type;

maintaining an indicator of fullness of the buffer; and

transferring a packet from the buffer according to a priority rule which

causes transferring of a packet identified by an entry in the queue out of the order of receipt, and

causes transferring of a packet not identified by an entry in the queue in the order of receipt the packet, if the parameters in the control field indicate the packet is ready for transfer and has not already been transferred, and the queue of entries is empty or the indicator of fullness exceeds a threshold.

23. An integrated circuit for use in a network interface for a host computer, comprising:

a first port adapted for at least one of receiving data from and transmitting data to the host processor, and second port adapted for at least one of receiving data from and transmitting data to a network;

a buffer coupled to the first and second ports which stores data packets from one of the first and second ports in an order of receipt, said packets identifiable as having respective packet types from a plurality of packet types; and

logic to transfer packets out of the buffer to the other of the first and second ports according to the order of receipt, and according to the respective packet types so that packets having a particular packet type are transferred out of the order of receipt, relative to packets having another packet type.

24. The integrated circuit of claim 23, comprising logic to maintain a list of packets stored in the buffer having the particular packet type, and wherein the logic to transfer packets is responsive to the list.

25. The integrated circuit of claim 23, comprising logic to set parameters associated with the packets in the buffer having the particular packet type, and the logic to transfer packets is responsive to the parameters.

26. The integrated circuit of claim 23, wherein the particular type of packet comprises a priority packet.

27. The integrated circuit of claim 23, wherein the particular type of packet comprises a packet suitable for processing with a security protocol.

28. The integrated circuit of claim 23, wherein the logic to transfer the packets includes processing resources which write a control field in the buffer in association with each packet, indicating the type of packet, whether the packet is ready for transfer, and whether the packet has already been transferred.

29. An integrated circuit for use in a network interface for a host computer, comprising:

a first port adapted for at least one of receiving data from and transmitting data to the host processor, and second port adapted for at least one of receiving data from and transmitting data to a network;

a buffer coupled to the first and second ports which stores data packets from one of the first and second ports in an order of receipt, said packets identifiable as having respective packet types from a plurality of packet types;

logic to transfer packets out of the buffer to the other of the first and second ports according to the order of receipt, and according to the respective packet types so that packets having a particular packet type are transferred out of the order of receipt, relative to packets having another packet type;

a data filter coupled with the buffer to generate identifiers which identify packets of data as members of one of a plurality of packet types when the packets are stored in the buffer; and

logic to write the identifiers in the buffer.

30. An integrated circuit for use in a network interface for a host computer, comprising:

a first port adapted for at least one of receiving data from and transmitting data to the host processor, and second port adapted for at least one of receiving data from and transmitting data to a network;

a buffer coupled to the first and second ports which stores data packets from one of the first and second ports in an order of receipt, said packets identifiable as having respective packet types from a plurality of packet types;

logic to transfer packets out of the buffer to the other of the first and second ports according to the order of receipt, and according to the respective packet types so that packets having a particular packet type are transferred out of the order of receipt, relative to packets having another packet type; and

a data filter coupled with the buffer to generate identifiers which identify packets of data stored in the buffer as members of one of a plurality of packet types.

31. An integrated circuit for use in a network interface for a host computer, comprising:

a first port adapted for at least one of receiving data from and transmitting data to the host processor, and second port adapted for at least one of receiving data from and transmitting data to a network;

a buffer coupled to the first and second ports which stores data packets from one of the first and second ports in an order of receipt, said packets identifiable as having respective packet types from a plurality of packet types; and

logic to transfer packets out of the buffer to the other of the first and second ports according to the order of receipt, and according to the respective packet types so that packets having a particular packet type are transferred out of the order of receipt, relative to packets having another packet type;

wherein the particular type of packet comprises a payload suitable for processing according to a particular process prior to transfer, and the integrated circuit includes logic, responsive to the particular packet type, to process the payload according to the particular process and generate control data associated with the particular packet indicating a state of the processing, and the logic to transfer the packet is responsive to the control data so that the particular packet may be transferred out of the order of receipt relative to other packets having other packet types and other packets having the particular packet type based on the control data.

32. The integrated circuit of claim 31, wherein the particular process comprises a security protocol compliant with IPsec.

33. An integrated circuit for use in a network interface for a host computer, comprising:

a first port adapted for at least one of receiving data from and transmitting data to the host processor, and second port adapted for at least one of receiving data from and transmitting data to a network;

a buffer coupled to the first and second ports which stores data packets from one of the first and second ports in an order of receipt, said packets identifiable as having respective packet types from a plurality of packet types; and

logic to transfer packets out of the buffer to the other of the first and second ports according to the order of receipt, and according to the respective packet types so that packets having a particular packet type are transferred out of the order of receipt, relative to packets having another packet type;

wherein the logic to transfer the packets includes processing resources which

set up a control field for each packet stored in the buffer;

write parameters in the control field indicating the packet type, and whether the packet has already been transferred;

maintain a queue of entries identifying packets having the particular packet type;

maintain an indicator of fullness of the buffer; and

transfer a packet from the buffer according to a priority rule which

causes transfer of a packet identified by an entry in the queue out of the order of receipt, and

causes transfer of a packet not identified by an entry in the queue in the order of receipt the packet, if the parameters in the control field indicate the packet has not already been transferred, and the queue of entries is empty or the indicator of fullness exceeds a threshold.

34. An integrated circuit for use in a network interface for a host computer, comprising:

a first port adapted for at least one of receiving data from and transmitting data to the host processor, and second port adapted for at least one of receiving data from and transmitting data to a network;

a buffer coupled to the first and second ports which stores data packets from one of the first and second ports in an order of receipt, said packets identifiable as having respective packet types from a plurality of packet types; and

logic to transfer packets out of the buffer to the other of the first and second ports according to the order of receipt, and according to the respective packet types so that packets having a particular packet type are transferred out of the order of receipt, relative to packets having another packet type;

wherein the logic to transfer the packets includes processing resources which

set up a control field for each packet stored in the buffer;

write a parameter in the control field indicating the packet type;

process packets having the particular packet type according to a particular process;

write a parameter in the control field indicating whether the processing according to the particular process is complete; and

transfer a packet from the buffer according to a priority rule which

skips transfer of a packet having the particular packet type if the parameter in the control field indicates the processing is not complete, and

causes transfer of a packet in the order of receipt, if parameters in the control field indicates the packet is ready for transfer.

35. An integrated circuit for use in a network interface for a host computer, comprising:

a first port adapted for at least one of receiving data from and transmitting data to the host processor, and second port adapted for at least one of receiving data from and transmitting data to a network;

a buffer coupled to the first and second ports which stores data packets from one of the first and second ports in an order of receipt, said packets identifiable as having respective packet types from a plurality of packet types; and

logic to transfer packets out of the buffer to the other of the first and second ports according to the order of receipt, and according to the respective packet types so that packets having a particular packet type are transferred out of the order of receipt, relative to packets having another packet type;

wherein the plurality of packet types includes first and second packet types in addition to the particular packet type, and the logic to transfer the packets includes processing resources which

set up a control field for each packet stored in the buffer;

write parameters in the control field indicating the packet type, and whether the packet has already been transferred;

maintain a queue of entries identifying packets having the particular packet type;

process packets having the second packet type according to a particular process;

write a parameter in the control field for packets having the second packet type indicating whether the processing according to the particular process is complete;

maintain an indicator of fullness of the buffer; and

transfer a packet from the buffer according to a priority rule which

causes transfer of a packet identified by an entry in the queue ahead of packets in the buffer having the first and second packet types relative to the order of receipt,

causes transfer of a packet having the first packet type in the order of receipt, if the parameters in the control field indicate the packet is ready for transfer, and the queue of entries is empty or the indicator of fullness exceeds a threshold, and

causes transfer of a packet having the second packet type after packets having the first packet type relative to the order of receipt if the parameter in the control field indicate the processing is complete.

36. The integrated circuit of claim 35, wherein the particular type of packet comprises a priority packet, and the second type of packet comprises a packet suitable for processing with a security protocol.