Non-disruptive clearing of varying address ranges from cache

• US 10,649,908 B2
• Filed: 02/21/2019
• Issued: 05/12/2020
• Est. Priority Date: 04/19/2017
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Ambroladze, Ekaterina M., Berger, Deanna P. D., Blake, Michael A., Mak, Pak-kin, Sonnelitter, III, Robert J., Tracy, Guy G., Wilson, Chad G.
• Primary Examiner(s): Rossiter, Sean D
• Application Number:
  US16/281,132
• Publication Number:
  US 20190179765A1
• Time in Patent Office: 446 Days
• Field of Search: None
• CPC Class Codes: G06F 12/0804 with main memory updating G06F12/0806 takes precedence
• CPC Class Codes: G06F 12/0864 using pseudo-associative means, e.g. set-associative or hashing
• CPC Class Codes: G06F 12/0891 using clearing, invalidating or resetting means
• CPC Class Codes: G06F 12/0897 with two or more cache hierarchy levels with multilevel cache hierarchies G06F12/0811
• CPC Class Codes: G06F 2212/1024 Latency reduction
• CPC Class Codes: G06F 2212/60 Details of cache memory

Abstract

In an approach for purging an address range from a cache, a processor quiesces a computing system. Cache logic issues a command to purge a section of a cache to higher level memory, wherein the command comprises a starting storage address and a range of storage addresses to be purged. Responsive to each cache of the computing system activating the command, cache logic ends the quiesce of the computing system. Subsequent to ending the quiesce of the computing system, Cache logic purges storage addresses from the cache, based on the command, to the higher level memory.

Claims

1. A method for purging an address range from a cache, the method comprising:

quiescing, by a processor, a computing system;

issuing a command to purge storage addresses from a cache to higher level memory, wherein the command comprises a starting storage address and a range of storage addresses to be purged;

responsive to each cache of the computing system activating the command, ending the quiesce of the computing system; and

subsequent to ending the quiesce of the computing system, purging storage addresses from the cache, based on the command, to the higher level memory.

2. The method of claim 1, further comprising:

concurrent to purging the storage addresses from the cache, identifying an attempt to access a first storage address within the range of storage addresses to be purged from the cache; and

responsive to the attempt, generating an invalid address response.

3. The method of claim 1, further comprising:

updating a configuration array with a location of the purged storage addresses.

4. The method of claim 1, wherein the command further comprises a multiplier.

5. The method of claim 4, wherein the range of storage addresses to be purged is based on the multiplier.

6. The method of claim 1, wherein activating the command further comprises causing the storage addresses from the cache to be inaccessible to operations attempting to access the storage addresses from the cache.

7. A computer program product for purging an address range from a cache, the computer program product comprising:

one or more computer readable storage media and program instructions stored on the one or more computer readable storage media, the program instructions comprising;

program instructions to quiesce a computing system;

program instructions to issue a command to purge storage addresses from a cache to higher level memory, wherein the command comprises a starting storage address and a range of storage addresses to be purged;

responsive to each cache of the computing system activating the command, program instructions to end the quiesce of the computing system; and

subsequent to the program instructions to end the quiesce of the computing system, program instructions to purge storage addresses from the cache, based on the command, to the higher level memory.

8. The computer program product of claim 7, further comprising:

concurrent to the program instructions to purge the storage addresses from the cache, program instructions to identify an attempt to access a first storage address within the range of storage addresses to be purged from the cache; and

responsive to the attempt, program instructions to generate an invalid address response.

9. The computing program product of claim 7, further comprising:

program instructions to update a configuration array with a location of the purged storage addresses.

10. The computer program product of claim 7, wherein the command further comprises a multiplier.

11. The computer program product of claim 10, wherein the range of storage addresses to be purged is based on the multiplier.

12. The computer program product of claim 7, wherein activating the command further comprises causing the storage addresses from the cache to be inaccessible to operations attempting to access the storage addresses from the cache.

13. A computer system for purging an address range from a cache, the computer system comprising:

one or more computer processors;

one or more computer readable storage media;

program instructions stored on the computer readable storage media for execution by at least one of the one or more processors, the program instructions comprising;

program instructions to quiesce a computing system;

program instructions to issue a command to purge storage addresses from a cache to higher level memory, wherein the command comprises a starting storage address and a range of storage addresses to be purged;

responsive to each cache of the computing system activating the command, program instructions to end the quiesce of the computing system; and

subsequent to the program instructions to end the quiesce of the computing system, program instructions to purge storage addresses from the cache, based on the command, to the higher level memory.

14. The computer system of claim 13, further comprising:

concurrent to the program instructions to purge the storage addresses from the cache, program instructions to identify an attempt to access a first storage address within the range of storage addresses to be purged from the cache; and

responsive to the attempt, program instructions to generate an invalid address response.

15. The computing system of claim 13, further comprising:

program instructions to update a configuration array with a location of the purged storage addresses.

16. The computer system of claim 13, wherein the command further comprises a multiplier.

17. The computer system of claim 13, wherein activating the command further comprises causing the storage addresses from the cache to be inaccessible to operations attempting to access the storage addresses from the cache.