US 6,289,391 B1Granted

System and method for performing external procedure calls from a server program to a client program while both are running in a heterogeneous computer

AssigneeUnisys Corporation

InventorsNorman Roy Smith, J. Calvin Hale, Mark Joseph Rentmeesters, Andrew D. Milligan

Life of this patent

Estimating the term…

Loading patent…

Abstract

In a heterogeneous computer system including at least one Client CPU, at least one Server CPU and a common memory disposed therebetween for storing first and second operating systems that control operation of the Client and Server CPUs, respectively. There is provided Client and Server Programs, both of which are stored in the same common memory. The Client Program is executed by the Client CPU and the Server Program is executed by the Server CPU. A method and system is disclosed wherein the Server Program is adapted for making function calls to the Client Program and the Client Program is adapted for returning results of the called function to the Server Program. The Server Program includes Procedures for invoking a Client Program function, converting parameters and result data from a format compatible with the first operating system to one compatible with the second operating system.

Claims25

Dependent claims

In a heterogeneous computer system having at least two CPU's and a common memory completely accessible by at least one of said CPUs and being disposed for storing at least two different operating systems that actively run simultaneously and concurrently control resources of said heterogeneous computer system, a method for performing external procedure calls between a first program stored in said common memory and being executed by a first one of said CPU's under control of a first one of said two operating systems and a second program stored in said common memory and being executed by a second one of said CPU's under control of a second one of said two operating systems, said method comprising the steps of:

a. said first program initiating said second program via a CPU-to-CPU signal bus between said at least two CPU's;
b. said second program calling a specific function located in said first program via said CPU-to-CPU signal bus;
c. said second program storing parameters, if any, in a second program stack having a portion thereof within said common memory;
d. said first program fetching directly from said second program stack said parameters, if any, and converting them from a format compatible with said second operating system to a format compatible with said first operating system;
e. said first program performing said specific function;
f. said first program converting results of the preceding step, if any, from a format compatible with said first operating system back to a format compatible with said second operating system;
g. said first program storing in a first program stack in having a portion thereof within said common memory said results to said second program;
and,
h. said second program fetching from said first program stack said results, if any.

6 more elements

In a heterogeneous computer system having at least two CPU's and a common memory completely accessible by at least one of said CPUs and being disposed for storing at least two different operating systems that actively run simultaneously and concurrently control resources of said heterogeneous computer system, a method for performing external procedure calls from a first program stored in said common memory and being executed by a first one of said CPU's under control of a first one of said two operating systems to a second program stored in said common memory and being executed by a second one of said CPU's under control of a second one of said two operating systems, said method comprising the steps of:

a. said first program fetching from said common memory a protocol procedure and passing to said second operating system an identification of said second program;
b. said second operating system attempting to initiate said second program identified in the preceding step and if successful indicating the same to said first program;
c. said second program fetching from said common memory a proxy procedure for calling a specific function in said first program;
d. said second program storing parameters, if any, in a second program stack having a portion thereof within said common memory for disposal to said first program;
e. said proxy procedure fetching from said common memory a protocol procedure for invoking said first program to perform a specific function;
f. said protocol procedure fetching from said common memory a specific stub procedure in said first program for performing said specific function;
g. said stub procedure fetching said parameters directly from said second program stack and converting said parameters, if any, from a format compatible with said second operating system to a format compatible with said first operating system;
h. placing said converted parameters in an activation record for said specific function in a first program stack having a portion thereof within said common memory;
i. said first program performing said specific function and storing the results, if any, in said first program stack;
j. said stub procedure fetching from said first program stack said results of the preceding steps, if any, and converting them from a format compatible with said first operating system back to a format compatible with said second operating system;
k. said first program storing in said second program, stack said results;
and,
l. said second program fetching from said second program stack said results.

10 more elements

Dependencies are inferred from the claim text.