USING SYMBOL INFORMATION FOR CATEGORIZATION OF DYNAMIC MEMORY ALLOCATIONS

• US 20130007400A1
• Filed: 06/30/2011
• Published: 01/03/2013
• Est. Priority Date: 06/30/2011
• Status: Active Grant

• Current Assignee: Red Hat, Inc. (International Business Machines Corporation)
• Original Assignee: Red Hat, Inc. (International Business Machines Corporation)
• Inventors: Malcolm, David Hugh
• Granted Patent: US 8,725,978 B2
• Time in Patent Office: Days
• US Class Current: 711/170
• CPC Class Codes: G06F 11/3636 by tracing the execution of the program
• CPC Class Codes: G06F 11/3664 Environments for testing or debugging software

Abstract

A programming and debugging system identifies one or more statically-allocated symbols in a symbol table for an inferior process. The statically-allocated symbols pertain to one or more structures for the inferior process. The inferior process has dynamic memory allocations in an inferior process memory space. The symbol table comprises data used to categorize the statically-allocated area of memory. The system locates the structures in the inferior process memory space and determines whether an address of the structures in the inferior process memory space matches an address of a block of the dynamically allocated area of memory. The system categorizes the block of dynamically allocated memory based on the determination of whether an address of the structures matches an address of a block of the dynamically allocated area of memory.

Claims

1. A method, implemented by a computing system programmed to perform the following, comprising:

identifying, by the computing system, one or more statically-allocated symbols in a symbol table for an inferior process, the one or more statically-allocated symbols pertaining to one or more structures for the inferior process, the inferior process having dynamic memory allocations in an inferior process memory space, the symbol table comprising data used to categorize the statically-allocated area of memory;

locating, by the computing system, the one or more structures in the inferior process memory space;

determining, by the computing system, whether an address of the one or more structures in the inferior process memory space matches an address of a block of the dynamically allocated area of memory; and

categorizing, by the computing system, the block of dynamically allocated memory based on the determination of whether an address of the one or more structures matches an address of a block of the dynamically allocated area of memory.

2. The method of claim 1, wherein a statically-allocated symbol pertains to a pointer to a structure.

3. The method of claim 1, further comprising:

iterating through other blocks of dynamically allocated memory within the inferior process memory space based on threshold data stored in memory; and

categorizing the other blocks of dynamically allocated memory based on the structure memory addresses for the statically-allocated symbols pertaining to the structures, wherein the threshold data limits the iterations.

4. The method of claim 1, further comprising:

iterating through blocks of dynamically allocated memory within a memory space that is layered over the inferior process memory space; and

categorizing the blocks of dynamically allocated memory within the layered memory space based on the structure memory addresses for the statically-allocated symbols pertaining to the structures.

5. The method of claim 1, wherein categorizing the block of dynamically allocated memory comprises:

determining that an address of the one or more structures pertaining to the statically-allocated symbols matches an address of a block of the dynamically allocated area of memory; and

categorizing the block as an instance of the structure.

6. The method of claim 1, further comprising:

casting the categorized block as an instance of a structure;

determining that the instance of the structure includes a pointer to a second structure;

locating the second structure in the memory within the inferior process;

determining whether an address of the second structure matches an address of a block of dynamically allocated memory; and

categorizing the block of dynamically allocated memory as an instance of the second structure upon determining that the address of the second structure matches an address of a block of dynamically allocated memory.

7. The method of claim 1, further comprising:

storing categorization data within a debugger process memory space, the categorization data indicating a category for the block of dynamically allocated memory, the debugger process being a process that is separate from the inferior process and having the debugger process memory space that is separate from the inferior process memory space;

generating memory categorization results for the dynamic memory allocations for the inferior process based on the categorization data to allow a user to optimize performance of the inferior process; and

displaying the memory categorization results in a graphical user interface (GUI) to show the categorization of the dynamically allocated area of memory of the inferior process.

8. A system comprising:

a persistent storage unit to store a symbol table for an inferior process, the inferior process having dynamic memory allocations, the symbol table comprising data used to categorize the statically-allocated areas of memory; and

a processing device coupled to the persistent storage unit to identify one or more statically-allocated symbols in the symbol table that pertain to one or more structures for the inferior process, to locate the one or more structure in the inferior process memory space, to determine whether an address of the one or more structures in the inferior process memory space matches an address of a block of the dynamically allocated are of memory, and to categorize by the inferior process the block of dynamically allocated memory based on the determination of whether an address of the one or more structures matches an address of a block of the dynamically allocated area of memory.

9. The system of claim 8, wherein a statically-allocated symbol pertains to a pointer to a structure.

10. The system of claim 8, wherein:

the persistent storage unit is further to store threshold data that limits the processing device iterating through other blocks of dynamically allocated memory within the inferior process memory space; and

the processing device is further to iterate through the other blocks of dynamically allocated memory within the inferior process memory space based on the threshold data, and to categorize by the inferior process of the other blocks of dynamically allocated memory based on the structure memory addresses for the statically-allocated symbols pertaining to the structures.

11. The system of claim 8, wherein the processing device is further to:

iterate through blocks of dynamically allocated memory within a memory space that is layered over the inferior process memory space, and to categorize by the inferior process of the blocks of dynamically allocated memory within the layered memory space based on the structure memory addresses for the statically-allocated symbols pertaining to the structures.

12. The system of claim 8, wherein the processing device is to categorize the block of dynamically allocated memory by:

determining that an address of the one or more structures pertaining to the statically-allocated symbols matches an address of a block of the dynamically allocated area of memory; and

categorizing the block as an instance of the structure.

13. The system of claim 8, wherein the processing device is further to:

cast the categorized block as an instance of the structure, to determine that the instance of the structure includes a pointer to a second structure, to locate the second structure in the memory within the inferior process, to determine whether an address of the second structure matches an address of a block of dynamically allocated memory, and to categorize by the inferior process the block of dynamically allocated memory as an instance of the second structure upon determining that the address of the second structure matches an address of a block of dynamically allocated memory.

14. The system of claim 8, wherein:

the persistent storage unit is further to store categorization data within a debugger process memory space, the categorization data indicating a category for the block of dynamically allocated memory, the debugger process being a process that is separate from the inferior process and having the debugger process memory space that is separate from the inferior process memory space; and

the processing device is further to generate memory categorization results for the dynamic memory allocations for the inferior process based on the categorization data to allow a user to optimize performance of the inferior process and to display the memory categorization results in a graphical user interface (GUI) to show the categorization of the dynamically allocated area of memory of the inferior process.

15. A non-transitory computer-readable storage medium including instructions that, when executed by a computer system, causes the computer system to perform a set of operations comprising:

identifying one or more statically-allocated symbols in a symbol table for an inferior process, the one or more statically-allocated symbols pertaining to one or more structures for the inferior process, the inferior process having dynamic memory allocations in an inferior process memory space, the symbol table comprising data used to categorize the statically-allocated area of memory;

locating the one or more structures in the inferior process memory space;

determining whether an address of the one or more structures in the inferior process memory space matches an address of a block of the dynamically allocated area of memory; and

categorizing the block of dynamically allocated memory based on the determination of whether an address of the one or more structures matches an address of a block of the dynamically allocated are of memory.

16. The non-transitory computer-readable storage medium claim 15, wherein a statically-allocated symbol pertains to a pointer to a structure.

17. The non-transitory computer-readable storage medium claim 15, further comprising:

iterating through other blocks of dynamically allocated memory within the inferior process memory space based on threshold data stored in memory; and

categorizing the other blocks of dynamically allocated memory based on the structure memory addresses for the statically-allocated symbols pertaining to the structures, wherein the threshold data limits the iterations.

18. The non-transitory computer-readable storage medium claim 15, further comprising:

iterating through blocks of dynamically allocated memory within a memory space that is layered over the inferior process memory space; and

categorizing the blocks of dynamically allocated memory within the layered memory space based on the structure memory addresses for the statically-allocated symbols pertaining to the structures.

19. The non-transitory computer-readable storage medium claim 15, wherein categorizing the usage of the block of dynamically allocated memory comprises:

determining that an address of the one or more structures pertaining to the statically-allocated symbols matches an address of a block of the dynamically allocated area of memory; and

categorizing the block as an instance of the structure.

20. The non-transitory computer-readable storage medium claim 19, further comprising:

casting the categorized block as an instance of the structure;

determining that the instance of the structure includes a pointer to a second structure;

locating the second structure in the memory within the inferior process;

determining whether an address of the second structure matches an address of a block of dynamically allocated memory; and

categorizing the block of dynamically allocated memory as an instance of the second structure upon determining that the address of the second structure matches an address of a block of dynamically allocated memory.