Method and apparatus for exchanging data between transactional and non-transactional input/output systems in a multi-processing, shared memory environment

• US 6,557,056 B1
• Filed: 12/30/1998
• Issued: 04/29/2003
• Est. Priority Date: 12/30/1998
• Status: Expired due to Term

• Current Assignee: RPX Clearinghouse LLC (RPX Corporation)
• Original Assignee: Nortel Networks Limited (Nortel Networks Corporation)
• Inventors: Lanteigne, Stephen, Lewis, David
• Primary Examiner(s): Shin, Christopher B.
• Assistant Examiner(s): Perveen, Rehana
• Application Number:
  US09/223,004
• Time in Patent Office: 1,581 Days
• Field of Search: 710/52, 710/53, 710/54, 710/55, 710/56, 710/57, 711/147
• US Class Current: 710/52
• CPC Class Codes: G06F 2209/548 Queue
• CPC Class Codes: G06F 9/466 Transaction processing
• CPC Class Codes: G06F 9/544 Buffers; Shared memory; Pipes
• CPC Class Codes: G06F 9/546 Message passing systems or structures, e.g. queues

Abstract

The present invention relates to a queuing system, implemented in the memory of a computer by the execution of a program element. The queuing system includes a queue with a plurality of memory slots, a write pointer and a read pointer. The write pointer permits to enqueue data elements in successive memory slots of the queue. The read pointer permits to dequeue data elements from the queue memory slots for processing, where these data elements are potentially non-dequeuable. Upon identifying a non-dequeuable data element in a particular memory slot of the queue, the read pointer is capable to skip over the particular memory slot and move on to a successive memory slot.

Claims

1. A queuing system for exchanging data elements between a transactional input/output (IO) system and a non-transactional IO system, said queuing system comprising:

a queue including a plurality of memory slots;

a write pointer for successively designating memory slots of said queue permitting a process of either one of the transactional system and the non-transactional system to access the memory slots for enqueuing data elements thereto;

a read pointer for successively designating memory slots of said queue permitting a process of either one of the transactional system and the non-transactional system to access the memory slots for dequeuing and processing data elements contained therein; and

a control functional block operative to control;

a) ownership of each one of said read and write pointers by a process of either one of the transactional system and the non-transactional system;

b) ownership of a memory slot of said queue by a process of either one of the transactional system and the non-transactional system;

said queuing system permitting a controllable exchange of data elements between the transactional system and the non-transactional system.

2. A queuing system as defined in claim 1, wherein a process owns a particular memory slot of said queue for a predetermined maximum period of time, whereby upon expiration of the maximum period of time said control functional block forces the process to relinquish ownership of the particular memory slot of said queue.

3. A queuing system as defined in claim 2, wherein when a process is enqueuing a data element to a particular memory slot of said queue, the process owns the particular memory slot of said queue until the process commits the data element to the particular memory slot of said queue.

4. A queuing system as defined in claim 3, wherein as said read pointer successively designates memory slots of said queue for dequeuing data elements therefrom, said read pointer is operative to bypass an owned memory slot and to designate the succeeding unowned memory slot.

5. A queuing system as defined in claim 3, wherein as said read pointer successively designates memory slots of said queue for dequeuing data elements therefrom, the progress of said read pointer is blocked by an owned memory slot.

6. A queuing system as defined in claim 1, wherein when said control functional block assigns ownership of said write pointer to a process of either one of the transactional system and the non-transactional system, the process acquires ownership of the particular memory slot of said queue designated by said write pointer at the time ownership of said write pointer is assigned to the process.

7. A queuing system as defined in claim 6, wherein once a process acquires ownership of a particular memory slot of said queue designated by said write pointer, the process relinquishes ownership of said write pointer whereby said write pointer designates the succeeding memory slot of said queue.

8. A queuing system as defined in claim 7, wherein when a process owns said write pointer, the process relinquishes ownership of said write pointer by line committing said write pointer.

9. A queuing system as defined in claim 1, wherein said queue is a circular buffer.

10. A queuing system as defined in claim 1, wherein said queuing system further includes a plurality of interfaces, each interface capable to perform a particular manipulation on said queue.

11. A queuing system as defined in claim 10, wherein said manipulation is either one of creating said queue and deleting said queue.

12. A queuing system as defined in claim 10, wherein said manipulation is either one of enqueuing a data element to said queue and dequeuing a data element from said queue.

13. A method for exchanging data elements between a transactional input/output (IO) system and a non-transactional IO system, said method comprising the steps of:

providing a queue that includes a plurality of memory slots;

implementing a write pointer function to successively designate memory slots of said queue to permit a process of either one of the transactional system and the non-transactional system to access the memory slots for enqueuing data elements thereto;

implementing a read pointer function to successively designate memory slots of said queue to permit a process of either one of the transactional system and the non-transactional system to access the memory slots for dequeuing and processing data elements contained therein; and

implementing a control functional block to control;

a) ownership of each one of said read and write pointers by a process of either one of the transactional system and the non-transactional system;

b) ownership of a memory slot of said queue by a process of either one of the transactional system and the non-transactional system;

permitting a controllable exchange of data elements between the transactional system and the non-transactional system.