System for querying a peripheral device to determine its processing capabilities and then offloading specific processing tasks from a host to the peripheral device when needed

• US 6,141,705 A
• Filed: 06/12/1998
• Issued: 10/31/2000
• Est. Priority Date: 06/12/1998
• Status: Expired due to Term

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Brandon, Kyle, Srinavas, Nk, Hyder, Jameel, Anand, Sanjay
• Primary Examiner(s): Lee, Thomas C.
• Assistant Examiner(s): ELAMIN, ABDELMONIEM I
• Application Number:
  US09/097,169
• Time in Patent Office: 872 Days
• Field of Search: 709/203, 709/219, 709/223, 711/39, 714/104, 710/15
• US Class Current: 710/15
• CPC Class Codes: G06F 2209/509 Offload
• CPC Class Codes: G06F 9/5044 considering hardware capabilities
• CPC Class Codes: G06F 9/5055 considering software capabilities, i.e. software resources associated or available to the machine
• CPC Class Codes: H04L 63/0428 wherein the data content is protected, e.g. by encrypting or encapsulating the payload
• CPC Class Codes: H04L 63/1458 Denial of Service
• CPC Class Codes: H04L 69/12 Protocol engines
• CPC Class Codes: H04L 69/22 Parsing or analysis of headers
• CPC Class Codes: H04L 69/24 Negotiation of communication capabilities
• CPC Class Codes: H04L 69/32 Architecture of open systems interconnection [OSI] 7-layer type protocol stacks, e.g. the interfaces between the data link level and the physical level
• CPC Class Codes: H04L 69/321 Interlayer communication protocols or service data unit [SDU] definitions; Interfaces between layers
• CPC Class Codes: H04L 9/40 Network security protocols

Abstract

The present invention is directed to a method and computer program product for offloading specific processing tasks that would otherwise be performed in a computer system'"'"'s processor and memory, to a peripheral device, or devices, that are connected to the computer. The computing task is then performed by the peripheral, thereby saving computer system resources for other computing tasks and increasing the overall computing efficiency of the computer system. In one preferred embodiment, the disclosed method is utilized in a layered network model, wherein computing tasks that are typically performed in network applications are instead offloaded to the network interface card (NIC) peripheral. An application executing on the computer system first queries the processing, or task offload capabilities of the NIC, and then selectively enables those capabilities that may be subsequently needed by the application. The specific processing capabilities of a NIC are made available by creating a task offload buffer data structure, which contains data indicative of the processing capabilities of the corresponding NIC. Once an application has discerned the capabilities of a particular NIC, it will selectively utilize any of the enabled task offload capabilities of the NIC by appending packet extension data to the network data packet that is forwarded to the NIC. The device driver of the NIC will review the data contained in the packet extension, and then cause the NIC to perform the specified operating task(s). This offloading of computing tasks on a per-packet basis allows an application to selectively offload tasks on a dynamic, as-needed basis. As such, applications executing on the computer system processor are able to offload tasks in instances where it is busy processing other computing tasks and processor overhead is high. Multiple tasks can also be offloaded in batches to a particular peripheral.

Claims

1. In a computer system environment having at least one software component and at least one peripheral hardware device, a method for dynamically offloading, on a per-packet basis and depending on the then current needs of the computer system, an operating task from the software component to the peripheral hardware device thereby freeing up host processor resources and increasing the overall efficiency of the computer system, the method comprising:

a step for querying the peripheral hardware device to determine the task offload capabilities of the peripheral hardware device;

a step for enabling selected task offload capabilities of the peripheral hardware device to the extent such selected task offload capabilities are needed for one or more packets;

in the event that an operating task to be performed for a packet by the software component corresponds to an enabled task offload capability on the peripheral hardware device, and depending on the then current needs of the computer system, performing the act of selectively offloading the operating task from the software component to the peripheral hardware device by sending a data packet to the peripheral hardware device indicating that the peripheral hardware device perform the specified operating task; and

a step for performing at the peripheral hardware device the offloaded operating task.

2. A computer-readable medium having computer-executable instructions for performing the steps and act recited in claim 1.

3. A method as recited in claim 1, wherein the peripheral hardware device is a network interface card (NIC) that is operatively connected to the computer system.

4. A method as recited in claim 1, wherein the software component is a network software application executing in a layered network model.

5. A method as recited in claim 1, wherein the task offload capabilities of the peripheral hardware device are queried by reading task data stored in at least one task offload buffer associated with the peripheral hardware device, wherein the task data is indicative of the particular task offload capability of the peripheral hardware device.

6. A method as recited in claim 5, wherein the peripheral hardware device has multiple task offload buffers associated with it, thereby defining multiple task offload capabilities of the peripheral hardware device.

7. A method as defined in claim 1, wherein the selected task offload capabilities of the peripheral hardware device are enabled by setting at least one flag indicator in a task offload buffer associated with the peripheral hardware device.

8. A method as defined in claim 1, wherein the packet is a network data packet comprising network data and packet extension data, wherein the packet extension data is comprised of at least one data field indicative of at least one operating task to be performed by the peripheral hardware device.

9. A method as defined in claim 8, wherein the peripheral hardware device is a Network Interface Card (NIC).

10. A method as defined in claim 1, wherein the operating task is selected from one or more of the following operating tasks:

a checksum operation;

an encryption operation;

a message digest calculation operation;

a TCP segmentation operation; and

a decryption operation.

11. A method as recited in claim 1, the software component comprising a transport protocol driver software component, the computer system including a network interface card (NIC) device driver, wherein the peripheral hardware device comprises a corresponding network interface card (NIC) connected to the computer system,

wherein the step for guerying the peripheral hardware device to determine the task offload capabilities of the peripheral hardware device comprises the following:

an act of creating a data structure that includes task data that identifies the task offload capabilities of the NIC;

an act of querying the task data contained within the data structure to identify the task offload capabilities of the NIC;

wherein the act of selectively offloading the operating task comprises an act of appending task offload data to the packet; and

wherein the step for performing the offloaded operating task comprises an act of performing the at least one offloaded task at the NIC in accordance with the appended task offload data.

12. A computer-readable medium having computer-executable instructions for performing the steps and acts recited in claim 11.

13. A method as defined in claim 11, wherein the data structure comprises:

a first data field containing data representing a type of task offload capability; and

a second data field containing data necessary for performing the task offload defined in the first data field.

14. A method as defined in claim 11, wherein the NIC is selectively enabled to perform at least one of the identified task offload capabilities by writing at least one data field into the data structure.

15. A method as defined in claim 11, wherein the task offload data appended to the packet comprises a first data field representing the type of offloaded task to be performed by the NIC when the NIC receives the packet.

16. A method as defined in claim 15, wherein the task offload data further comprises a second data field containing at east one pointer to a memory location, the memory location containing data needed to perform the offloaded task specified in the first data field of the task offload data.

17. A computer-readable medium having computer-executable instructions for dynamically offloading, on a per-packet basis and depending on the then current needs of the computer system, a computing task to be executed at a network interface card (NIC) that is connected to a computer system thereby freeing up host processor resources and increasing the overall efficiency of the computer system, the computer-readable medium further including computer-executable instructions comprising:

a step for notifying applications executing on the computer system of any task offload processing capabilities of the NIC;

for every network data packet that is destined for the NIC from an application executing on the computer system, a step for reviewing a packet extension data structure appended to the data packet, the packet extension data structure containing information for identification of one or more particular operating tasks being offloaded to the NIC; and

a step for causing the NIC to perform an operating task in accordance with data contained within the packet extension data structure appended to the network data packet.

18. A computer-readable medium as defined in claim 17, wherein the computer-executable instructions for performing the notifying step comprise the steps of creating a task offload buffer data structure comprising a first data field containing data representing a type of task offload capability for the NIC.

19. A computer-readable medium as defined in claim 18, wherein the task offload buffer data structure further comprises at least one additional data field containing data necessary for performing the task offload defined in the first data field.

20. A computer-readable medium as defined in claim 17, wherein the packet extension data structure appended to the network data packet comprises a first data field representing the type of operating task that is to be performed by the NIC.

21. A computer-readable medium as defined in claim 20, wherein the packet extension data structure further comprises at least one additional data field containing at least one pointer to a memory location, the memory location containing data needed to perform the operating task specified in the first data field of the packet extension data structure.

22. In a computer system environment having at least one software component and at least one peripheral hardware device, a method for dynamically offloading, on a per-packet basis and depending on the then current needs of the computer system, an operating task from the software component to the peripheral hardware device thereby freeing up host processor resources and increasing the overall efficiency of the computer system, the method comprising:

an act of reading task data stored in at least one task offload buffer associated with the peripheral hardware device, wherein the task data is indicative of the particular task offload capability of the peripheral hardware device

an act of querying the task data contained within the at least one task offload buffer to identify the task offload capabilities of the peripheral hardware device;

an act of setting at least one flag indicator in a task offload buffer associated with the peripheral hardware device, wherein the flag indicator represents the enabling of an associated task offload capability needed for one or more packet;

in the event that an operating task to be performed for a packet by the software component corresponds to an enabled task offload capability on the peripheral hardware device, and depending on the then current needs of the computer system, performing the act of selectively offloading the operating task from the software component to the peripheral hardware device by appending task offload data to a data packet and sending the data packet to the peripheral hardware device; and

an act of performing the at least one offloaded task at the peripheral hardware device in accordance with the appended task offload data.

23. A computer-readable medium having computer-executable instructions for performing the acts recited in claim 22.

24. A method as recited in claim 22, wherein the peripheral hardware device is a network interface card (NIC) that is operatively connected to the computer system.

25. A method as recited in claim 22, wherein the software component is a network software application executing in a layered network model.

26. A method as recited in claim 22, wherein the peripheral hardware device has multiple task offload buffers associated with it, thereby defining multiple task offload capabilities of the peripheral hardware device.

27. A method as defined in claim 22, wherein the peripheral hardware device is a Network Interface Card (NIC).

28. A method as defined in claim 22, wherein the operating task is selected from one or more of the following operating tasks:

a checksum operation;

an encryption operation;

a message digest calculation operation;

a TCP segmentation operation; and

a decryption operation.