Abstract: A computer system that supports virtualization may maintain multiple address spaces. Each guest operating system employs guest virtual addresses (GVAs), which are translated to guest physical addresses (GPAs). A hypervisor, which manages one or more guest operating systems, translates GPAs to root physical addresses (RPAs). A merged translation lookaside buffer (MTLB) caches translations between the multiple addressing domains, enabling faster address translation and memory access. The MTLB can be logically addressable as multiple different caches, and can be reconfigured to allot different spaces to each logical cache. Further, a collapsed TLB provides an additional cache storing collapsed translations derived from the MTLB.

Abstract: A computer system that supports virtualization may maintain multiple address spaces. Each guest operating system employs guest virtual addresses (GVAs), which are translated to guest physical addresses (GPAs). A hypervisor, which manages one or more guest operating systems, translates GPAs to root physical addresses (RPAs). A merged translation lookaside buffer (MTLB) caches translations between the multiple addressing domains, enabling faster address translation and memory access. The MTLB can be logically addressable as multiple different caches, and can be reconfigured to allot different spaces to each logical cache.

Abstract: In a network processor, a “port-kind” identifier (ID) is assigned to each port. Parsing circuitry employs the port-kind ID to select the configuration information associate with a received packet. The port kind ID can also be stored at a data structure presented to software, along with a larger port number (indicating an interface and/or channel). Based on the port kind ID and extracted information about the packet, a backpressure ID is calculated for the packet. The backpressure ID is implemented to assign a priority to the packet, as well as determine whether a traffic threshold is exceeded, thereby enabling a backpressure signal to limit packet traffic associated with the particular backpressure ID.

Abstract: A network processor includes a schedule, sync and order (SSO) module for scheduling and assigning work to multiple processors. The SSO includes an on-deck unit (ODU) that provides a table having several entries, each entry storing a respective work queue entry, and a number of lists. Each of the lists may be associated with a respective processor configured to execute the work, and includes pointers to entries in the table. A pointer is added to the list based on an indication of whether the associated processor accepts the WQE corresponding to the pointer.

Abstract: In a network processor, a “port-kind” identifier (ID) is assigned to each port. Parsing circuitry employs the port-kind ID to select the configuration information associate with a received packet. The port kind ID can also be stored at a data structure presented to software, along with a larger port number (indicating an interface and/or channel). Based on the port kind ID and extracted information about the packet, a backpressure ID is calculated for the packet. The backpressure ID is implemented to assign a priority to the packet, as well as determine whether a traffic threshold is exceeded, thereby enabling a backpressure signal to limit packet traffic associated with the particular backpressure ID.

Abstract: An integrated circuit processes communication packets and comprises a pointer cache and control logic. The pointer cache store pointers that correspond to external buffers that are external to the integrated circuit and configured to store the communication packets. The control logic allocates the external buffers as the corresponding pointers are read from the pointer cache and de-allocates the external buffers as the corresponding pointers are written back to the pointer cache.

Abstract: An integrated circuit processes a communication packet and comprises a core processor and scheduling circuitry. The core processor executes a software application that directs the core processor to process the communication packet. The scheduling circuitry retrieves first scheduling parameters cached in a context buffer for the packet and executes a first algorithm based on the first scheduling parameters to schedule subsequent transmission of the communication packet.

Abstract: Circuitry to free the core processor from performing the explicit read operation required to read data into the internal register set. The processor's register set is expanded and a “shadow register” set is provided. While the core processor is processing one event the “context” and “data” and other associated information for the next event is loaded into the shadow register set. When the core processor finishes processing an event, the core processor switches to the shadow register set and it can begin processing the next event immediately. With short service routines, there might not be time to fully pre-fetch the “context” and “data” associated with the next event before the current event ends. In this case, the core processor still starts processing the next event and the pre-fetch continues during the event processing.

Abstract: An integrated circuit comprises co-processor circuitry and a core processor. The co-processor circuitry comprises context buffers and data buffers. The co-processor circuitry receives and stores one of the communication packets in one of the data buffers. The co-processor circuitry correlates the one communication packet with one of a plurality of channel descriptors. The co-processor circuitry associates the one data buffer with one of the context buffers holding the one channel descriptor to maintain the correlation between the one communication packet and the one channel descriptor. The co-processor circuitry prevents multiple valid copies of the one channel descriptor from existing in the context buffers. In some examples of the invention, this is accomplished by tracking a number of the data buffers associated with the one context buffer.

Abstract: An integrated circuit processes communication packets and comprises a core processor and scheduling circuitry. The core processor executes a software application that directs the core processor to process the communication packets. The scheduling circuitry comprises multiple scheduling boards where at least some of the scheduling boards have multiple priority levels. The scheduling circuitry processes the scheduling boards to schedule and subsequently initiate transmission of the communication packets.

Abstract: An integrated circuit processes communication packets and comprises co-processor circuitry and a core processor. The co-processor circuitry is configured to operate in parallel with the core processor. The co-processor circuitry receives and stores the communication packets in data buffers. The co-processor circuitry also determines a prioritized processing order. The core processor executes a packet processing software application that directs the processor to process the communication packets in the data buffers based on the prioritized processing order.

Abstract: Circuitry to free the core processor from performing the explicit read operation required to read data into the internal register set. The processor's register set is expanded and a “shadow register” set is provided. While the core processor is processing one event the “context” and “data” and other associated information for the next event is loaded into the shadow register set. When the core processor finishes processing an event, the core processor switches to the shadow register set and it can begin processing the next event immediately. With short service routines, there might not be time to fully pre-fetch the “context” and “data” associated with the next event before the current event ends. In this case, the core processor still starts processing the next event and the pre-fetch continues during the event processing.

Abstract: A method of limiting, in a digital processor, low-priority utilization of a resource in favor of high-priority utilization of the resource comprises determining a value predictive of high-priority utilization of the resource. Low-priority utilization of the resource is inhibited if the determined predictive value is greater than a threshold. On the other hand, if the predictive value is less than or equal to the threshold, then low-priority utilization of the resource is allowed. In a preferred embodiment, the predictive value is derived by counting the number of actual high-priority utilizations of the resource out of the last N opportunities in which the resource could have been utilized for a high-priority need. Preferably, recent utilizations are given more weight than others. In a preferred embodiment, the resource comprises one of main memory, instruction cache memory, or data cache memory.

Abstract: A method of limiting, in a digital processor, low-priority utilization of a resource in favor of high-priority utilization of the resource comprises determining a value predictive of high-priority utilization of the resource. Low-priority utilization of the resource is inhibited if the determined predictive value is greater than a threshold. On the other hand, if the predictive value is less than or equal to the threshold, then low-priority utilization of the resource is allowed. In a preferred embodiment, the predictive value is derived by counting the number of actual high-priority utilizations of the resource out of the last N opportunities in which the resource could have been utilized for a high-priority need. Preferably, recent utilizations are given more weight than others. In a preferred embodiment, the resource comprises one of main memory, instruction cache memory, or data cache memory.

Abstract: A method of limiting, in a digital processor, low-priority utilization of a resource in favor of high-priority utilization of the resource comprises determining a value predictive of high-priority utilization of the resource. Low-priority utilization of the resource is inhibited if the determined predictive value is greater than a threshold. On the other hand, if the predictive value is less than or equal to the threshold, then low-priority utilization of the resource is allowed. In a preferred embodiment, the predictive value is derived by counting the number of actual high-priority utilizations of the resource out of the last N opportunities in which the resource could have been utilized for a high-priority need. Preferably, recent utilizations are given more weight than others. In a preferred embodiment, the resource comprises one of main memory, instruction cache memory, or data cache memory.

Abstract: An integrated circuit processes communication packets and comprises a pointer cache and control logic. The pointer cache store pointers that correspond to external buffers that are external to the integrated circuit and configured to store the communication packets. The control logic allocates the external buffers as the corresponding pointers are read from the pointer cache and de-allocates the external buffers as the corresponding pointers are written back to the pointer cache.