forked from luck/tmp_suning_uos_patched
e1cf33aafb
Heterogeneous memory systems provide memory nodes with different latency and bandwidth performance attributes. Provide a new kernel interface for subsystems to register the attributes under the memory target node's initiator access class. If the system provides this information, applications may query these attributes when deciding which node to request memory. The following example shows the new sysfs hierarchy for a node exporting performance attributes: # tree -P "read*|write*"/sys/devices/system/node/nodeY/accessZ/initiators/ /sys/devices/system/node/nodeY/accessZ/initiators/ |-- read_bandwidth |-- read_latency |-- write_bandwidth `-- write_latency The bandwidth is exported as MB/s and latency is reported in nanoseconds. The values are taken from the platform as reported by the manufacturer. Memory accesses from an initiator node that is not one of the memory's access "Z" initiator nodes linked in the same directory may observe different performance than reported here. When a subsystem makes use of this interface, initiators of a different access number may not have the same performance relative to initiators in other access numbers, or omitted from the any access class' initiators. Descriptions for memory access initiator performance access attributes are added to sysfs stable documentation. Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Tested-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Keith Busch <keith.busch@intel.com> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Tested-by: Brice Goglin <Brice.Goglin@inria.fr> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
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| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.