Method and apparatus for making inter-process procedure calls through shared memory

• US 8,191,076 B2
• Filed: 08/05/2010
• Issued: 05/29/2012
• Est. Priority Date: 10/25/2005
• Status: Active Grant

• Current Assignee: Oracle International Corporation (Oracle Corporation)
• Original Assignee: Oracle International Corporation (Oracle Corporation)
• Inventors: Lari, Mohammad Shoaib, Krishnaswamy, Srinath
• Primary Examiner(s): Puente, Emerson
• Assistant Examiner(s): VERDI, KIMBLEANN C
• Application Number:
  US12/851,345
• Publication Number:
  US 20100313206A1
• Time in Patent Office: 663 Days
• Field of Search: 719/312
• US Class Current: 719/312
• CPC Class Codes: G06F 9/52 Program synchronisation; Mutual exclusion, e.g. by means of semaphores
• CPC Class Codes: G06F 9/547 Remote procedure calls [RPC]; Web services

Abstract

One embodiment of the present invention provides a system that facilitates making an inter-process procedure call through a shared memory that is shared between a client process and a server process, wherein the client makes the inter-process procedure call as if the client is making a local procedure call, but the procedure call actually executes on the server. The system operates by an Application Programming Interface (API) to allow the client to make an inter-process procedure call. The system then allocates a section of the shared memory for the data structure parameters of the inter-process procedure call.

Claims

1. A method comprising:

receiving a request from a client at a server to make an inter-process procedure call;

allocating, at the server, a section of shared memory for the inter-process procedure call;

acquiring a lock, by the server, on the section of shared memory;

determining, by the server, whether a flag indicating a completion of the inter-process procedure call has been cleared by the client;

in response to the flag not being cleared,

releasing the lock, by the server;

waiting for a predetermined amount of time, by the server; and

reacquiring the lock, by the server; and

in response to the flag being cleared, processing the inter-process procedure call by;

retrieving, by the server, parameters stored by the client from the section of shared memory;

executing, by the server, the inter-process procedure call;

storing, by the server, results of the inter-process procedure call in the section of shared memory;

setting the flag, by the server, to indicate the completion of the inter-process procedure call; and

releasing the lock, by the server.

2. The method of claim 1, wherein the client and server reside on a same machine.

3. The method of claim 1, further comprising:

allowing the client to acquire the lock; and

in response to the flag being set, allowing the client to process the results of the inter-process procedure call from the section of shared memory at the client.

4. The method of claim 1, wherein the client operates in a multi-threaded environment.

5. The method of claim 1, wherein the server services calls from multiple clients by waiting on locks on more than one section of shared memory.

6. The method of claim 1, wherein the server comprises multiple threads, and wherein each thread serves one or more clients.

7. The method of claim 1, wherein the client is an enterprise application running on a middle tier in a multi-tier application environment.

8. A non-transitory computer readable storage medium storing instructions which when executed by a computer cause the computer to perform a method, the method comprising:

receiving a request from a client at a server to make an inter-process procedure call;

allocating, at the server, a section of shared memory for the inter-process procedure call;

acquiring a lock, by the server, on the section of shared memory;

determining, by the server, whether a flag indicating a completion of the inter-process procedure call has been cleared by the client;

in response to the flag not being cleared,

releasing the lock, by the server;

waiting for a predetermined amount of time, by the server; and

reacquiring the lock, by the server; and

in response to the flag being cleared, processing the inter-process procedure call by;

retrieving, by the server, parameters stored by the client from the section of shared memory;

executing, by the server, the inter-process procedure call;

storing, by the server, results of the inter-process procedure call in the section of shared memory;

setting the flag, by the server, to indicate the completion of the inter-process procedure call; and

releasing the lock, by the server.

9. The storage medium of claim 8, wherein the client and server reside on a same machine.

10. The storage medium of claim 8, wherein the method further comprises:

allowing the client to acquire the lock; and

in response to the flag being set, allowing the client to process the results of the inter-process procedure call from the section of shared memory at the client.

11. The storage medium of claim 8, wherein the client operates in a multi-threaded environment.

12. The storage medium of claim 8, wherein the server services calls from multiple clients by waiting on locks on more than one section of shared memory.

13. The storage medium of claim 8, wherein the server comprises multiple threads, and wherein each thread serves one or more clients.

14. The storage medium of claim 8, wherein the client is an enterprise application running on a middle tier in a multi-tier application environment.

15. A computer system, comprising:

a processor;

a shared memory;

a receiving mechanism coupled to the processor and configured to receive a request from a client process of a client at a server process of a server to make an inter-process procedure call;

a memory allocation mechanism, at the server, configured to allocate a section of the shared memory for the inter-process procedure call;

a lock acquisition/release mechanism configured to acquire/release a lock on the section of shared memory;

a determining mechanism configured to determine whether a flag indicating a completion of the inter-process procedure call has been cleared by the client process, wherein in response to the flag not being cleared, the lock acquisition/release mechanism is configured to;

release the lock, by the server process;

wait for a predetermined amount of time, by the server process; and

reacquire the lock, by the server process;

a processing mechanism configured to process the inter-process procedure call on the server, which comprises;

a parameter retrieval mechanism configured to retrieve parameters stored by the client process from the section of shared memory in response to the flag being cleared;

an execution mechanism configured to execute the inter-process procedure call;

a flag-setting mechanism configured to set a flag to indicate that the server process has completed processing the inter-process procedure call; and

a result-storing mechanism configured to store results of the inter-process procedure call in the section of shared memory; and

wherein the lock acquisition/release mechanism is further configured to release the lock, by the server process.

16. The computer system of claim 15, wherein the client process and server process reside on the same machine.

17. The computer system of claim 15, wherein the server process is configured to:

allow the client process to acquire the lock; and

in response to the flag being set, allow the client process to process the results of the inter-process procedure call from the section of shared memory at the client.

18. The computer system of claim 15, wherein the client process operates in a multi-threaded environment.

19. The computer system of claim 15, wherein the server process services calls from multiple clients by waiting on locks on more than one section of shared memory.

20. The computer system of claim 15, wherein the server process comprises multiple threads, and wherein each thread serves one or more clients.

21. The computer system of claim 15, wherein the client process is an enterprise application running on a middle tier in a multi-tier application environment.