Apparatus and method for controlling allocation of data into a cache storage
US10394716B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 6, 2018 |
| Grant date | Aug 27, 2019 |
| Priority date | — |
| Expiry date | Apr 6, 2038 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F2212/1052
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
An apparatus and method are provided for controlling allocation of data into cache storage. The apparatus comprises processing circuitry for executing instructions, and a cache storage for storing data accessed when executing the instructions. Cache control circuitry is arranged, while a sensitive allocation condition is determined to exist, to be responsive to the processing circuitry speculatively executing a memory access instruction that identifies data to be allocated into the cache storage, to allocate the data into the cache storage and to set a conditional allocation flag in association with the data allocated into the cache storage. The cache control circuitry is then responsive to detecting an allocation resolution event, to determine based on the type of the allocation resolution event whether to clear the conditional allocation flag such that the data is thereafter treated as unconditionally allocated, or to cause invalidation of the data in the cache storage. Such an approach can reduce the vulnerability of a cache to speculation-based cache timing side-channel attacks.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.