A data processing system for processing data comprising: ownership circuitry to enforce ownership rights of memory regions, a given more privileged state memory region having a given owning process specified from among a plurality of processes, said given owning process having exclusive rights to control access to said given memory region; and context switching circuitry responsive to receipt of an interrupt to trigger a context switch from a first active process to a second active process whereby one or more items of state for use in restarting said first process is saved to one or more context data memory regions owned by said first process and one or more items of state accessible to said second process and dependent upon processing by said first process is overwritten prior to commencing execution of said second process.

A communications device that includes a requester and a responder may support multiple transaction classes, including an ordered transaction class, while maintaining a bifurcated requester/responder architecture. Before a responder has a non-posted transaction response to transmit on an interconnect, it receives an indication from the requester that there is not a pending posted transaction on the interconnect.

An integrated circuit device has a first central processing unit including a digital signal processing (DSP) engine, and a plurality of contexts, each context having a CPU context with a plurality of registers and a DSP context, wherein the DSP context has control bits and a plurality of DSP registers, wherein after a reset of the integrated circuit device the control bits of all DSP context are linked together such that data written to the control bits of a DSP context is written to respective control bits of all other DSP contexts and only after a context switch to another context and a modification of at least one of the control bits of the another DSP context, the control bits of the another context is severed from the link to form independent control bits of the DSP context.

A semiconductor apparatus for reducing context-switch time includes at least one CPU, at least one memory and a logic circuit. The central processor unit includes a control unit, a process unit and registers. The memory includes at least one region for storing information of multiple tasks. The information of each of the tasks includes an identification, priority, status and context. The logic circuit uses direct memory access to read and write the registers of the CPU and move data between the CPU registers and the memory. The logic circuit is operable to instruct the control unit to stop and resume the execution of CPU instruction.

Compiler-optimized context switching may include receiving an instruction indicating a preferred preemption point comprising an instruction address; storing the preferred preemption point in a data structure; determining, based on the data structure, that the preferred preemption point has been reached by a first thread; determining that preemption of the first thread for a second thread has been requested; and performing a context switch to the second thread.

A computer system, processor, and method for processing information is disclosed that includes at least one computer processor for processing instructions, the processor having a history buffer having a plurality of entries for storing information associated with a processor instruction evicted from a logical register, the history buffer having at least one recovery port; a logical register mapper for recovering information from the history buffer, the mapper having restore ports to recover information from the history buffer; and a restore multiplexor configured to receive as inputs information from one or more of the history buffer recovery ports, and configured to output information to one or more of the logical register mapper restore ports. The processor, system and/or method configured to improve flush recovery bandwidth.

A processor includes an instruction pipeline. The pipeline can be operated alternatively in a multi-thread mode and in a single-thread mode. In the multi-thread mode, the instruction pipeline processes multiple threads in an interleaved or simultaneous manner. In the single-thread mode, the pipeline processes a single thread. The instruction pipeline comprises multiple functional units, each of which is reserved for one thread among the multiple threads when the pipeline is in the multi-thread mode and reserved for one context layer among multiple context layers when the instruction pipeline is in the single-thread mode.

Recovering microprocessor logical register values by: partitioning a register mapper by logical register type; providing a plurality of recovery ports; assigning a logical register type to a recovery port; receiving a restore required instruction; and mapping SRB (save and restore buffer) values to the register mapper by logical register type.

Data processing apparatus comprises one or more interconnected processing elements; each processing element being configured to execute processing instructions of program tasks; each processing element being configured to save context data relating to a program task following execution of that program task by that processing element; and to load context data, previously saved by that processing element or another of the processing elements, at resumption of execution of a program task; each processing element having respective associated format definition data to define one or more sets of data items for inclusion in the context data; the apparatus comprising format selection circuitry to communicate the format definition data of each of the processing elements with others of the processing elements and to determine, in response to the format definition data for each of the processing elements, a common set of data items for inclusion in the context data.

A computer system, processor, and method for processing information is disclosed that includes at least one computer processor for processing instructions, the processor having a history buffer having a plurality of entries for storing information associated with a processor instruction evicted from a logical register, the history buffer having a at least one recovery port; a logical register mapper for recovering information from the history buffer, the mapper having restore ports to recover information from the history buffer; and a restore multiplexor configured to receive as inputs information from one or more of the history buffer recovery ports, and configured to output information to one or more of the logical register mapper restore ports. The processor, system and/or method configured to improve flush recovery bandwidth.