Using DMA for copying performance counter data to memory
AssigneeInternational Business Machines Corporation
InventorsAlan Gara, Valentina Salapura, Robert W. Wisniewski
Life of this patent
Estimating the term…
Abstract
A device for copying performance counter data includes hardware path that connects a direct memory access (DMA) unit to a plurality of hardware performance counters and a memory device. Software prepares an injection packet for the DMA unit to perform copying, while the software can perform other tasks. In one aspect, the software that prepares the injection packet runs on a processing core other than the core that gathers the hardware performance counter data.
Claims19
A device for copying performance counter data, comprising:
- at least one processing core;
- a memory;
- a plurality of hardware performance counters operable to collect counts of selected hardware-related activities;
- a direct memory access unit having a DMA controller operable to copy data between the memory and the plurality of hardware performance counters;
- and
- an interconnecting path connecting the processing core, the memory, the plurality of hardware performance counters, and the direct memory access unit,
- wherein the copying of the performance counter data between the hardware performance counters and the memory is performed by the DMA controller without disturbing a processing core of the at least one processing core, on which a measured computation of one or more of the hardware performance counters is occurring.
A method of copying performance counter data, comprising:
- establishing a path between a direct memory access unit to a plurality of hardware performance units, the path further connecting to a memory device;
- and
- initiating a direct memory access unit to copy data between the plurality of hardware performance units and the memory device,
- wherein the copying of the performance counter data between the hardware performance units and the memory device is performed by the direct memory access unit without disturbing a processing core, on which a measured computation of one or more of the hardware performance counters is occurring.
A non-transitory computer readable storage medium storing a program of instructions executable by a machine to perform a method copying performance counter data, comprising:
- establishing a path between a direct memory access unit to a plurality of hardware performance units, the path further connecting to a memory device;
- and
- initiating a direct memory access unit to copy data between the plurality of hardware performance units and the memory device,
- wherein the copying of the performance counter data between the hardware performance units and the memory device is performed by the direct memory access unit without disturbing a processing core, on which a measured computation of one or more of the hardware performance counters is occurring.
Dependencies are inferred from the claim text.