Nvidia Corporation

Kaushal Agarwal

Jay Gupta

Devesh Mittal

Jonathon Evans

Srinivas Santosh Kumar Madugula

Ashutosh Pandey

Alexander E Van Brunt

Justin Bennett

Gosagan Padmanabhan

A host may use address translation to convert virtual addresses to physical addresses for endpoints, which may then submit memory access requests for physical addresses. The host may incorporate the physical address and a signature of the physical address generated using a private key into a translated address field of a response to a translation request. An endpoint may treat the combination as a translated address by storing it in an entry of a translation cache, and accessing the entry for inclusion in a memory access request. The host may generate a signature of the translated address from the request using the private key, with the result being compared to the signature from the request. The memory access request may be verified when the compared values match, and the memory access may be performed using the translated address.

Preventing unauthorized translated access using address signing

Memory page table invalidations for multiple execution contexts (clients or guests) of a memory system are conventionally queued in a single physical command queue. The multiple execution contexts contend to access the queue, resulting in low performance. Instead of contending with other execution contexts to insert invalidation commands into a single physical command queue, a virtual interface and one or more virtual command queues are allocated to each guest. The execution contexts may simultaneously transmit invalidation commands for the memory system through their respective virtual interface. Additionally, each execution context may also transmit other (less often issued) commands through a hypervisor. Error handling and/or illegal access checks specific to invalidation commands that were previously performed by the hypervisor are now performed by the respective virtual interface(s).

Technique for efficiently allowing simultaneous access to resources in a computing system

Techniques are disclosed for reducing the time required to read and write data to memory. Data reads and/or writes can be delayed when error correction code (ECC) bits, which are used to detect and/or correct data corruption, are written to memory. Writing ECC bits can take longer in some instances than writing data bits because an ECC write may involve a read/modify/write operation, as opposed to just simply writing the bits to memory. Some latencies associated with writing ECC bits can be hidden by interleaving ECC writes with data writes. However, if insufficient data writes are available for interleaving, hiding such latencies become difficult. Thus, various techniques are disclosed, for example, where ECC writes are deferred until a sufficient number of data writes become available for interleaving. By interleaving ECC writes, the disclosed techniques decrease the overall time required to read and write data to memory.

Performant inline ECC architecture for DRAM controller

A memory management unit responds to an invalidate by class command by identifying a marker for a class of cache entries that the invalidate by class command is meant to invalidate. The memory management unit stores the active marker as a retired marker and then sets the active marker to the next available marker. Thereafter, the memory management sends an acknowledgement signal (e.g., to the operating system) while invalidating the cache entries having the class and the retired marker in the background. By correlating markers with classes of cache entries, the memory management can more quickly respond to class invalidation requests.

Growing community of inventors

Bengaluru, India

Kaushal Agarwal