Advanced Micro Devices Corporation

Hewlett-packard Company

Hewlett-packard Development Company, L.p.

Jay E Fleischman

Michael Estlick

Paul J Moyer

Jeffery C Brauch

Erik D Swanson

Gabriel H Loh

John Kalamatianos

William Louie Walker

Michael T Clark

Michael Christopher Sedmak

Kevin Altair Hurd

Anne P Scott

Jagadish B Kotra

Emil Talpes

Marius Evers

Tarun Nakra

J Michael Hill

Akhil Arunkumar

Sneha V Desai

Yasuko Eckert

Bradford Michael Beckmann

Maurice B Steinman

Donald R Weiss

Douglas Benson Hunt

Debjit Das Sarma

John William Bockhaus

Krishnan V Ramani

Kelvin Domnic Goveas

Kai Troester

John Kelley

Marko Scrbak

Neil N Marketkar

Thaddeus Fortenberry

David M Russinoff

Mark M Gibson

Hanbing Liu

Carl E Lemonds

Andrej Kocev

Derrick Allen Aguren

Eric H Van Tassell

Brian M Lay

Debjit DasSarma

Tim J Wilkens

Jeffrey C Brauch

Chun Liu

Johnny C Chu

Robert E Weidner

Michael W Long

Gautam Tarasingh Hazari

Richard McGowen, Ii

A coprocessor such as a floating-point unit includes a pipeline that is partitioned into a first portion and a second portion. A controller is configured to provide control signals to the first portion and the second portion of the pipeline. A first physical distance traversed by control signals propagating from the controller to the first portion of the pipeline is shorter than a second physical distance traversed by control signals propagating from the controller to the second portion of the pipeline. A scheduler is configured to cause a physical register file to provide a first subset of bits of an instruction to the first portion at a first time. The physical register file provides a second subset of the bits of the instruction to the second portion at a second time subsequent to the first time.

Differential pipeline delays in a coprocessor

An approach is provided for implementing register based single instruction, multiple data (SIMD) lookup table operations. According to the approach, an instruction set architecture (ISA) can support one or more SIMD instructions that enable vectors or multiple values in source data registers to be processed in parallel using a lookup table or truth table stored in one or more function registers. The SIMD instructions can be flexibly configured to support functions with inputs and outputs of various sizes and data formats. Various approaches are also described for supporting very large lookup tables that span multiple registers.

Register based SIMD lookup table operations

In response to generating one or more speculative prefetch requests for a last-level cache, a processor determines prefetch analytics for the generated speculative prefetch requests and compares the determined prefetch analytics of the speculative prefetch requests to selection thresholds. In response to a speculative prefetch request meeting or exceeding a selection threshold, the processor selects the speculative prefetch request for issuance to a memory-side cache controller. When one or more system conditions meet one or more condition thresholds, the processor issues the selected speculative prefetch request to the memory-side cache controller. The memory-side cache controller then retrieves the data indicated in the selected speculative prefetch request from a memory and stores it in a memory-side cache in the data fabric coupled to the last-level cache.

Selective speculative prefetch requests for a last-level cache

Systems, apparatuses, and methods for employing system probe filter aware last level cache insertion bypassing policies are disclosed. A system includes a plurality of processing nodes, a probe filter, and a shared cache. The probe filter monitors a rate of recall probes that are generated, and if the rate is greater than a first threshold, then the system initiates a cache partitioning and monitoring phase for the shared cache. Accordingly, the cache is partitioned into two portions. If the hit rate of a first portion is greater than a second threshold, then a second portion will have a non-bypass insertion policy since the cache is relatively useful in this scenario. However, if the hit rate of the first portion is less than or equal to the second threshold, then the second portion will have a bypass insertion policy since the cache is less useful in this case.

System probe aware last level cache insertion bypassing

Processor-guided execution of offloaded instructions using fixed function operations is disclosed. Instructions designated for remote execution by a target device are received by a processor. Each instruction includes, as an operand, a target register in the target device. The target register may be an architected virtual register. For each of the plurality of instructions, the processor transmits an offload request in the order that the instructions are received. The offload request includes the instruction designated for remote execution. The target device may be, for example, a processing-in-memory device or an accelerator coupled to a memory.

Processor-guided execution of offloaded instructions using fixed function operations

In response to eviction of a first clean data block from an intermediate level of cache in a multi-cache hierarchy of a processing system, a cache controller accesses an address of the first clean data block. The controller initiates a fetch of the first clean data block from a system memory into a last-level cache using the accessed address.

Re-fetching data for L3 cache data evictions into a last-level cache

A pipeline includes a first portion configured to process a first subset of bits of an instruction and a second portion configured to process a second subset of the bits of the instruction. A first clock mesh is configured to provide a first clock signal to the first portion of the pipeline. A second clock mesh is configured to provide a second clock signal to the second portion of the pipeline. The first and second clock meshes selectively provide the first and second clock signals based on characteristics of in-flight instructions that have been dispatched to the pipeline but not yet retired. In some cases, a physical register file is configured to store values of bits representative of instructions. Only the first subset is stored in the physical register file in response to the value of the zero high bit indicating that the second subset is equal to zero.

Clock mesh-based power conservation in a coprocessor based on in-flight instruction characteristics

A processing system includes a processor, a memory, and an operating system that are used to allocate a page table caching memory object (PTCM) for a user of the processing system. An allocation of the PTCM is requested from a PTCM allocation system. In order to allocate the PTCM, a plurality of physical memory pages from a memory are allocated to store a PTCM page table that is associated with the PTCM. A lockable region of a cache is designated to hold a copy of the PTCM page table, after which the lockable region of the cache is subsequently locked. The PTCM page table is populated with page table entries associated with the PTCM and copied to the locked region of the cache.

System and method for page table caching memory

Systems and methods selectively bypass address-generation hardware in processor instruction pipelines. In an embodiment, a processor includes an address-generation stage and an address-generation-bypass-determination unit (ABDU). The ABDU receives a load/store instruction. If an effective address for the load/store instruction is not known at the ABDU, the ABDU routes the load/store instruction via the address-generation stage of the processor. If, however, the effective address of the load/store instruction is known at the ABDU, the ABDU routes the load/store instruction to bypass the address-generation stage of the processor.

Systems and methods for selectively bypassing address-generation hardware in processor instruction pipelines

A system includes a multi-core processor that includes a scheduler. The multi-core processor communicates with a system memory and an operating system. The multi-core processor executes a first process and a second process. The system uses the scheduler to control a use of a memory bandwidth by the second process until a current use in a control cycle by the first process meets a first setpoint of use for the first process when the first setpoint is at or below a latency sensitive (LS) floor or a current use in the control cycle by the first process exceeds the LS floor when the first setpoint exceeds the LS floor.

Scheduling memory bandwidth based on quality of service floorbackground

Systems, apparatuses, and methods for tracking system resource utilization of guest virtual machines (VMs). Counters may be maintained to track resource utilization of different system resources by different guest VMs executing on the system. When a guest VM initiates execution, stored values may be loaded into the resource utilization counters. While the guest VM executes, the counters may track the resource utilization of the guest VM. When the guest VM terminates execution, the counter values may be written to a virtual machine control block (VMCB) corresponding to the guest VM. Scaling factors may be applied to the counter values to normalize the values prior to writing the values to the VMCB. A cloud computing environment may utilize the tracking mechanisms to guarantee resource utilization levels in accordance with users' service level agreements.

Mechanism for resource utilization metering in a computer system

A method includes allocating a first single-cycle instruction to a first pipeline that picks single-cycle instructions for execution in program order. The method further includes marking at least one source register of the first single-cycle instruction as ready for execution in the first pipeline in response to all older single-cycle instructions allocated to the first pipeline being ready and eligible to be picked for execution. An apparatus includes a decoder to decode a first single-cycle instruction and to allocate the first single-cycle instruction to a first pipeline. The apparatus further includes a scheduler to pick single-cycle instructions for execution by the first pipeline in program order and to mark at least one source register of the first single-cycle instruction as ready for execution in the first pipeline in response to determining that all older single-cycle instructions allocated to the first pipeline are ready and eligible.

Single cycle instruction pipeline scheduling

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Fort Collins, CO, United States of America

Jay E Fleischman