Data processing system

• US 20080072236A1
• Filed: 09/10/2007
• Published: 03/20/2008
• Est. Priority Date: 03/10/2005
• Status: Active Grant

• Current Assignee: Xilinx, Inc. (Advanced Micro Devices, Inc.)
• Original Assignee: SolarFlare Communications Incorporated (Advanced Micro Devices, Inc.)
• Inventors: Riddoch, David, Law, Greg, Pope, Steven
• Granted Patent: US 8,650,569 B2
• Time in Patent Office: Days
• US Class Current: 718/108
• CPC Class Codes: G06F 21/57 Certifying or maintaining trusted computer platforms, e.g. secure boots or power-downs, version controls, system software checks, secure updates or assessing vulnerabilities
• CPC Class Codes: G06F 9/461 Saving or restoring of program or task context
• CPC Class Codes: G06F 9/4843 by program, e.g. task dispatcher, supervisor, operating system
• CPC Class Codes: G06F 9/526 Mutual exclusion algorithms
• CPC Class Codes: G06F 9/545 where tasks reside in different layers, e.g. user- and kernel-space
• CPC Class Codes: H04L 45/00 Routing or path finding of packets in data switching networks routing or path finding in wireless networks H04W40/00
• CPC Class Codes: H04L 45/02 Topology update or discovery
• CPC Class Codes: H04L 45/54 Organization of routing tables

Abstract

A data processing system comprising an operating system for supporting processes, such that the process are associated with one or more resources and the operating system being arranged to police the accessing by processes of resources so as to inhibit a process from accessing resources with which it is not associated. Part of this system is an interface for interfacing between each process and the operating system and a memory for storing state information for at least one process. The interface may be arranged to analyze instructions from the processes to the operating system, and upon detecting an instruction to re-initialize a process cause state information corresponding to that pre-existing state information to be stored in the memory as state information for the re-initialized process and to be associated with the resource.

Claims

1. A data processing system comprising:

an operating system for supporting processes, each process being associated with one or more resources, the operating system being arranged to police the accessing by processes of resources so as to inhibit a process from accessing resources with which it is not associated, and being responsive to instructions of a certain type to re-initialise a process;

an interface for interfacing between each process and the operating system; and

a memory for storing state information for at least one process, the state information being associated with a resource;

the interface being arranged to analyse instructions from the processes to the operating system, and being arranged to, on detecting an instruction to re-initialise a process so as to be associated with a resource that is associated with pre-existing state information, cause state information corresponding to that pre-existing state information to be stored in the memory as state information for the re-initialised process and to be associated with the resource.

2. A data processing system as claimed in claim 1, wherein the said instructions include exec( ) instructions.

3. A data processing system as claimed in claim 1, wherein the interface is arranged to, when two or more resources are associated with the process, cause the said state information corresponding to the said pre-existing state information to be associated with the resource in response to an attempt to access the resource.

4. A data processing system as claimed in claim 1, wherein the operating system is responsive to instructions of another type to duplicate a process.

5. A data processing system as claimed in claim 4, wherein the said instructions of another type include fork( ) instructions.

6. A data processing system as claimed in any claim 1, wherein the resource with which the state information is associated is a memory area storing data for transmission and/or reception by the data processing system.

7. A data processing system as claimed in claim 6, wherein the state information is one or more of:

data transmission information, reception state information, information defining a virtual hardware interface, TCP windows, information defining unacknowledged buffers and information defining timeout values.

8. A data processing system as claimed in any claim 1, wherein the system is arranged to be capable of using the state information to form a memory mapping onto the resource.

9. A data processing system as claimed in any claim 1, wherein the operating system has a table indicating which state information is associated with which resource.

10. A data processing system as claimed in claim 1, wherein the interface is arranged to, on detecting an instruction to re-initialize a process so as to be associated with a resource that is associated with pre-existing state information, store a record of that instruction and then pass the instruction to the operating system.

11. A data processing system as claimed in claim 10, wherein the operating system is arranged to call the interface to configure state information for a re-initialised process, and the interface is arranged to, on being called to configure state information for a process to check whether it has a record of there having been an instruction to re-initialise that process so as to be associated with a resource that is associated with preexisting state information;

and if so, cause state information corresponding to that pre-existing state information to be stored in the memory as state information for the process and to be associated with the resource, and otherwise generate fresh state information for the process.

12. A data processing system as claimed in claim 1, wherein each resource is identifiable by means of a file descriptor.

13. A data processing system as claimed in claim 12, wherein a resource can be identifiable by multiple file descriptors.

14. A data processing system as claimed in claim 13, wherein the operating system is arranged to, in response to instructions to re-initialise a process and allocate a new file descriptor to that process, preferentially allocate a new resource to that process, identifiable by the new file descriptor.

15. A data processing system as claimed in claim 1, wherein the state information is stored in memory that is shared between the operating system and the interface.

16. A data processing system as claimed in claim 1, wherein the interface is a library.

17. A data processing system as claimed in claim 1, wherein the interface is an application program interface.

18. An interface for use by a data processing system comprising an operating system for supporting processes, each process being associated with one or more resources, the operating system being arranged to police the accessing by processes of resources so as to inhibit a process from accessing resources with which it is not associated, and being responsive to instructions of a certain type to re-initialise a process and a memory for storing state information for at least one process, the state information being associated with a resource;

the interface being for interfacing between each process and the operating system; and

being arranged to analyse instructions from the processes to the operating system, and being arranged to, on detecting an instruction to re-initialise a process so as to be associated with a resource that is associated with pre-existing state information, cause state information corresponding to that pre-existing state information to be stored in the memory as state information for the re-initialised process and to be associated with the resource.

19. A data carrier storing program data defining an interface as claimed in claim 18.

20. A method for processing instructions in a data processing system comprising:

an operating system for supporting processes, each process being associated with one or more resources, the operating system being arranged to police the accessing by processes of resources so as to inhibit a process from accessing resources with which it is not associated, and being responsive to instructions of a certain type to re-initialise a process;

an interface for interfacing between each process and the operating system; and

a memory for storing state information for at least one process, the state information being associated with a resource;

the method comprising the steps of;

analysing instructions from the processes to the operating system; and

on detecting an instruction to re-initialise a process so as to be associated with a resource that is associated with pre-existing state information, causing state information corresponding to that pre-existing state information to be stored in the memory as state information for the re-initialised process and to be associated with the resource.

21-92. -92. (canceled)