Processor-implemented systems and methods for event handling

• US 8,572,617 B2
• Filed: 07/21/2009
• Issued: 10/29/2013
• Est. Priority Date: 07/21/2009
• Status: Active Grant

• Current Assignee: SAS Institute Incorporated
• Original Assignee: SAS Institute Incorporated
• Inventors: Shorb, Charles Scott
• Primary Examiner(s): KAWSAR, ABDULLAH AL
• Application Number:
  US12/506,718
• Publication Number:
  US 20110023032A1
• Time in Patent Office: 1,561 Days
• Field of Search: None
• US Class Current: 718/102
• CPC Class Codes: G06F 9/522 Barrier synchronisation

Abstract

Processor-implemented systems and methods are provided for synchronization of a thread, wherein the thread waits for one or more events to occur before continuing execution. A processor-implemented system and method can include a wait data structure which stores event conditions in order to determine when the thread should continue execution. Event objects, executing on one or more data processors, allow for thread synchronization. A pointer is stored with respect to a wait data structure in order to provide visibility of event conditions to the event objects. The thread continues execution when the stored event conditions are satisfied.

Claims

1. A computer-implemented method, comprising:

initializing a group of multiple threads in a computer system, wherein the group of multiple threads execute in a multi-thread environment;

synchronizing the group of multiple threads by restricting one thread of the group from executing until multiple event conditions are satisfied, wherein each of the multiple event conditions corresponds to a different one of the multiple events;

initializing multiple event objects, wherein each of the multiple event objects stores information about a different one of the multiple events and a corresponding event condition, and wherein each of the multiple event objects is associated with multiple methods including a wait method for updating and accessing the event condition information stored by the object;

registering the multiple event objects, wherein registering an event object includes using the wait method to perform a wait operation to determine a status of an event by referencing an event condition information corresponding to the event stored by the event object and generating and storing a pointer associated with the event object;

initializing a wait data structure, wherein the wait data structure holds a counter, wherein the counter is configured to indicate when all of the multiple event conditions are satisfied, and wherein initializing includes linking a pointer to the wait data structure;

associating the one restricted thread of the group with the wait data structure;

updating the counter when an event condition is satisfied;

determining that all of the multiple event conditions are satisfied when the counter value reaches zero; and

in response to determining that all of the multiple event conditions are satisfied, ceasing to restrict the one thread of the group from executing.

2. The method of claim 1, wherein storing a pointer provides visibility of an event condition corresponding to an event, and wherein the visibility is provided to an event object corresponding to the event.

3. The method of claim 1, wherein synchronizing the group of multiple threads is done without an operating system lock.

4. The method of claim 1, wherein each of the multiple event objects further includes a method for clearing event information at the event object.

5. The system of claim 1, wherein each of the multiple event objects further includes a post method.

6. The method of claim 1, wherein the events are asynchronous events.

7. A system, comprising:

one or more data processors; and

one or more non transitory computer-readable storage media containing instructions configured to cause the one or more processors to perform operations including;

initializing a group of multiple threads in a computer system, wherein the group of multiple threads execute in a multi-thread environment;

synchronizing the group of multiple threads by restricting one thread of the group from executing until multiple event conditions are satisfied, wherein each of the multiple event conditions corresponds to a different one of the multiple events;

initializing multiple event objects, wherein each of the multiple event objects stores information about a different one of the multiple events and a corresponding event condition, and wherein each of the multiple event objects is associated with multiple methods including a wait method for updating and accessing the event condition information stored by the object;

registering the multiple event objects, wherein registering an event object includes using the wait method to perform a wait operation to determine a status of an event by referencing an event condition information corresponding to the event stored by the event object and generating and storing a pointer associated with the event object;

initializing a wait data structure, wherein the wait data structure holds a counter, wherein the counter is configured to indicate when all of the multiple event conditions are satisfied, and wherein initializing includes linking a pointer to the wait data structure;

associating the one restricted thread of the group with the wait data structure;

updating the counter when an event condition is satisfied;

determining that all of the multiple event conditions are satisfied when the counter value reaches zero; and

in response to determining that all of the multiple event conditions are satisfied, ceasing to restrict the one thread of the group from executing.

8. The system of claim 7, wherein storing a pointer provides visibility of an event condition corresponding to an event, and wherein the visibility is provided to an event object corresponding to the event.

9. The system of claim 7, wherein synchronizing the group of multiple threads is done without an operating system lock.

10. The system of claim 7, wherein each of the multiple event objects further includes a method for clearing event information at the event object.

11. The system of claim 7, wherein each of the multiple event objects further includes a post method.

12. The system of claim 7, wherein the events are asynchronous events.

13. A computer-program product tangibly embodied in a non-transitory machine readable storage medium, and including instructions configured to cause a data processing apparatus to perform operations including:

initializing a group of multiple threads in a computer system, wherein the group of multiple threads execute in a multi-thread environment;

synchronizing the group of multiple threads by restricting one thread of the group from executing until multiple event conditions are satisfied, wherein each of the multiple event conditions corresponds to a different one of the multiple events;

initializing multiple event objects, wherein each of the multiple event objects stores information about a different one of the multiple events and a corresponding event condition, and wherein each of the multiple event objects is associated with multiple methods including a wait method for updating and accessing the event condition information stored by the object;

registering the multiple event objects, wherein registering an event object includes using the wait method to perform a wait operation to determine a status of an event by referencing an event condition information corresponding to the event stored by the event object and generating and storing a pointer associated with the event object;

initializing a wait data structure, wherein the wait data structure holds a counter, wherein the counter is configured to indicate when all of the multiple event conditions are satisfied, and wherein initializing includes linking a pointer to the wait data structure;

associating the one restricted thread of the group with the wait data structure;

updating the counter when an event condition is satisfied;

determining that all of the multiple event conditions are satisfied when the counter value reaches zero; and

in response to determining that all of the multiple event conditions are satisfied, ceasing to restrict the one thread of the group from executing.

14. The computer-program product of claim 13, wherein storing a pointer provides visibility of an event condition corresponding to an event, and wherein the visibility is provided to an event object corresponding to the event.

15. The computer-program product of claim 13, wherein synchronizing the group of multiple threads is done without an operating system lock.

16. The computer-program product of claim 13, wherein each of the multiple event objects further includes a method for clearing event information at the event object.

17. The computer-program product of claim 13, wherein each of the multiple event objects further includes a post method.

18. The computer-program product of claim 13, wherein the events are asynchronous events.