US 6,557,166 B2 · Program correcting method and system

Abstract

Correction of a program which resides on a main storage and which is simultaneously callable by a plurality of command processors is performed by minimizing the stop time of a computer system without reloading a program. A particular command processor calls a correction execution program which corrects a program in accordance with a program correction command. The correction execution program reads program correction information, sets correction execution declaration information in all entries of other command processor in the correction execution declaration area of the main storage and after clearing all entries, the correction execution program corrects the program in accordance with the program correction information. The correction execution program sets correction completion reporting information in all entries for all of the other command processors in the correction completion reporting area of the main storage. The correction execution program waits for the correction completion reporting area to be cleared, at which time it sends the corrected program to the external storage. The program to be corrected calls a correction wait program, which recognizes the command processor which has called the correction wait program itself, checks an entry of the appropriate command processor in the correction execution declaration area. When the correction execution declaration information has been set, the correction wait program clears the correction execution declaration information, repeatedly checks the entry of the appropriate command processor in the correction completion reporting area, and when the correction completion reporting information has been set, clears same to thereby terminate the processing.

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Claims8

Dependent claims

A computer program on a storage medium for correcting a program stored in a main storage, access to which is shared by a plurality of command processors which can call said program simultaneously, said computer program when executed causes a computer to perform the steps of:

ensuring a first area and a second area, each having subareas corresponding to the respective command processors in said main storage;
designating a command processor which executes program correction from among a plurality of command processors;
fetching, by a first program, program correction information including at least a correction place and contents of a second program;
setting, by said first program, a flag in each of said subareas of said first area other than a subarea corresponding to the designated command processor in accordance with a command from the designated command processor;
calling a third program from said second program which is run by one of said plurality of command processors other than the designated processor;
causing, by said third program, the respective command processors other than the designated command processor to determine whether flags have been set in subareas of said first area corresponding to the respective command processors other than the designated command processor;
clearing, by said third program, the flags, if set, in each of said subareas of said first area corresponding to the respective command processors other than the designated command processor;
determining whether the flags have been cleared in the subareas of said first area corresponding to the respective command processors other than the designated command processor;
correcting the program to be corrected in accordance with the correction information in said first program when the flags in all of said subareas of said first area other than the subarea for the designated command processor are determined to have been cleared;
and
setting flags, by said first program, in all of said subareas of said second area other than the subarea corresponding to the designated command processor when the correction to the program to be corrected has been completed.

8 more elements

Dependencies are inferred from the claim text.

Description2,324 words

Summary855 words

#The present invention relates to methods of correcting a program in a computer system, and more particularly to a method of correcting a program which resides always on a main storage of a computer system which is difficult to stop.

#As a method of correcting a program in a computer system, there is a method of rewriting a program in its entirety in the computer system by reloading a corrected program. A method of correcting a program in a computer system without reloading such a program is disclosed in JP-A-3-97030 entitled “PROGRAM CORRECTING SYSTEM” in which a correcting program provided beforehand in the computer system is replaced with a program to be corrected.

#Correction to a program having a reentrant structure constructed such that two or more tasks can be used simultaneously, which is an object of the present invention, by reloading a corrected program has been found impractical because it requires much labor for initialization in the reloading of the corrected program. The method of correcting a program by replacing a correcting program provided beforehand in the computer system with a program to be corrected has the following problems. For a program having a reentrant structure such as that of the present invention, it has been found that there is a danger that a program may run by another command processor in the course of its correction, which should be avoided. It has also been found desirable even in such a case to minimize the time in which the running of the program has been avoided to thereby minimize the influence on the availability factor of the system.

Brief description of the drawings3 figures

#FIG. 1 is a block diagram indicative of the essential portion of a computer system as one embodiment of the present invention;

#FIG. 2 is a flow chart indicative of processing by a correction execution program called by a command processor IPm; and

#FIG. 3 is a flow chart indicative of the processing of a correction wait program 16 called by a program 15 to be corrected, when the program correction is executed.

Detailed description1,396 words

#One embodiment of a computer system according to the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a block diagram indicative of the essential portion of a computer system as one embodiment of the present invention In FIG. 1, reference numeral 10 denotes a user console through which the operator inputs a correction command for a program; 11, an external storage which stores correction information 21 which contains addresses of a portion of the program to be corrected and information on the content of the program to be corrected; 120, 121, . . . , 12n, corresponding command processors IP0, IP1, . . . , IPn which are connected to a main storage 20, which contains a system control program 13, which in turn, includes a correction execution program 14 executed when the system receives a command for program correction, a program 15 to be corrected, and a correction wait program 16 which is called by the program 15. The system control program 13 has a storage area 17 for program correction information 21 received from the external storage 11. The main storage 20 has a correction execution declaration area 18 and a correction completion reporting area 19. Reference characters A0, A1, . . . , An denote correction execution declaration area entries. Reference characters B0, B1, . . . , Bn denote entries in the correction completion reporting area corresponding to the respective command processors IP0, IP1, . . . , IPn.

#Actual correction to a program will be described next. When the system control program 13 of the main storage 20 receives a request for program correction by the operator through the user console 10, it designates one (IPm in the present embodiment) of the plurality of command processors IP connected to the main storage 20 and commands the IPm to call the correction execution program. Upon receiving the command, the command processor IPm executes the correction execution program 14 of the main storage 20.

#FIG. 2 is a flow chart indicative of processing by a correction execution program called by a command processor IPm. FIG. 3 is a flow chart indicative of the processing of a correction wait program 16 called by a program 15 to be corrected, when the program correction is executed. Referring to FIGS. 2 and 3, when the correction execution program 14 receives a startup command by the command processor IPm at step 205, it transfers program correction information 21 from the external storage 11 to the program correction information storage area 17 of the system control program 13 (step 201). The correction execution program 14 determines at step 202 whether the transfer at step 201 has succeeded. If there is no program correction information 21 in the external storage 11 or the program correction information 21 cannot be transferred due to some failure of the external storage 11, it informs the user console 10 of this fact (step 204) and terminates the processing. When the transfer has succeeded, the IPm checks whether the program correction information 21 is proper by comparing program correction information 21 in which an uncorrected program and a program to be corrected are contained with the program 15 to be corrected (step 203). When the propriety of the program correction information 21 can not be confirmed, the correction execution program 14 displays a message to that effect on the console 10 and reports it to the operator (step 204) to thereby terminate the processing.

Facts

Application

09/750,039Filed 29 Dec 2000 · continuation

Priority

JP 7-08465816 Mar 1995

Published

US 2001/0000825 A13 May 2001

Granted

29 Apr 2003

Term ended

26 Apr 2016

Estimated · how

20 years from earliest known nonprovisional domestic filing plus recorded patent term adjustment, including 49 days of adjustment. Maintenance-fee lapses, terminal disclaimers and statutory extensions have not been checked. The continuity chain may be incomplete; this is not an enforceability determination.

Classification3 codes

G06F 8/71
Software maintenance or management: version control ; Configuration management
G06F 8/656
Updates: while running
G06F
Computing and data processing

Program correcting method and system

Life of this patent

Program correcting method and system

Life of this patent

Life of this patent

Abstract

Drawings

Drawings

Claims8

Description2,324 words

Drawings

Classification3 codes

Life of this patent

Description2,324 words