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+What:           /sys/devices/system/cpu/
+Date:           pre-git history
+Contact:        Linux kernel mailing list <linux-kernel@vger.kernel.org>
+Description:
+                A collection of both global and individual CPU attributes
+
+                Individual CPU attributes are contained in subdirectories
+                named by the kernel's logical CPU number, e.g.:
+
+                /sys/devices/system/cpu/cpu#/
+
+What:           /sys/devices/system/cpu/sched_mc_power_savings
+                /sys/devices/system/cpu/sched_smt_power_savings
+Date:           June 2006
+Contact:        Linux kernel mailing list <linux-kernel@vger.kernel.org>
+Description:    Discover and adjust the kernel's multi-core scheduler support.
+
+                Possible values are:
+
+                0 - No power saving load balance (default value)
+                1 - Fill one thread/core/package first for long running threads
+                2 - Also bias task wakeups to semi-idle cpu package for power
+                    savings
+
+                sched_mc_power_savings is dependent upon SCHED_MC, which is
+                itself architecture dependent.
+
+                sched_smt_power_savings is dependent upon SCHED_SMT, which
+                is itself architecture dependent.
+
+                The two files are independent of each other. It is possible
+                that one file may be present without the other.
+
+                Introduced by git commit 5c45bf27.
+
+
+What:           /sys/devices/system/cpu/kernel_max
+                /sys/devices/system/cpu/offline
+                /sys/devices/system/cpu/online
+                /sys/devices/system/cpu/possible
+                /sys/devices/system/cpu/present
+Date:           December 2008
+Contact:        Linux kernel mailing list <linux-kernel@vger.kernel.org>
+Description:    CPU topology files that describe kernel limits related to
+                hotplug. Briefly:
+
+                kernel_max: the maximum cpu index allowed by the kernel
+                configuration.
+
+                offline: cpus that are not online because they have been
+                HOTPLUGGED off or exceed the limit of cpus allowed by the
+                kernel configuration (kernel_max above).
+
+                online: cpus that are online and being scheduled.
+
+                possible: cpus that have been allocated resources and can be
+                brought online if they are present.
+
+                present: cpus that have been identified as being present in
+                the system.
+
+                See Documentation/cputopology.txt for more information.
+
+
+
+What:           /sys/devices/system/cpu/cpu#/node
+Date:           October 2009
+Contact:        Linux memory management mailing list <linux-mm@kvack.org>
+Description:    Discover NUMA node a CPU belongs to
+
+                When CONFIG_NUMA is enabled, a symbolic link that points
+                to the corresponding NUMA node directory.
+
+                For example, the following symlink is created for cpu42
+                in NUMA node 2:
+
+                /sys/devices/system/cpu/cpu42/node2 -> ../../node/node2
+
+
+What:           /sys/devices/system/cpu/cpu#/topology/core_id
+                /sys/devices/system/cpu/cpu#/topology/core_siblings
+                /sys/devices/system/cpu/cpu#/topology/core_siblings_list
+                /sys/devices/system/cpu/cpu#/topology/physical_package_id
+                /sys/devices/system/cpu/cpu#/topology/thread_siblings
+                /sys/devices/system/cpu/cpu#/topology/thread_siblings_list
+Date:           December 2008
+Contact:        Linux kernel mailing list <linux-kernel@vger.kernel.org>
+Description:    CPU topology files that describe a logical CPU's relationship
+                to other cores and threads in the same physical package.
+
+                One cpu# directory is created per logical CPU in the system,
+                e.g. /sys/devices/system/cpu/cpu42/.
+
+                Briefly, the files above are:
+
+                core_id: the CPU core ID of cpu#. Typically it is the
+                hardware platform's identifier (rather than the kernel's).
+                The actual value is architecture and platform dependent.
+
+                core_siblings: internal kernel map of cpu#'s hardware threads
+                within the same physical_package_id.
+
+                core_siblings_list: human-readable list of the logical CPU
+                numbers within the same physical_package_id as cpu#.
+
+                physical_package_id: physical package id of cpu#. Typically
+                corresponds to a physical socket number, but the actual value
+                is architecture and platform dependent.
+
+                thread_siblings: internel kernel map of cpu#'s hardware
+                threads within the same core as cpu#
+
+                thread_siblings_list: human-readable list of cpu#'s hardware
+                threads within the same core as cpu#
+
+                See Documentation/cputopology.txt for more information.
+
+
+What:           /sys/devices/system/cpu/cpuidle/current_driver
+                /sys/devices/system/cpu/cpuidle/current_governer_ro
+Date:           September 2007
+Contact:        Linux kernel mailing list <linux-kernel@vger.kernel.org>
+Description:    Discover cpuidle policy and mechanism
+
+                Various CPUs today support multiple idle levels that are
+                differentiated by varying exit latencies and power
+                consumption during idle.
+
+                Idle policy (governor) is differentiated from idle mechanism
+                (driver)
+
+                current_driver: displays current idle mechanism
+
+                current_governor_ro: displays current idle policy
+
+                See files in Documentation/cpuidle/ for more information.
+
+
+What:      /sys/devices/system/cpu/cpu*/cache/index*/cache_disable_X
+Date:      August 2008
+KernelVersion:  2.6.27
+Contact:        mark.langsdorf@amd.com
+Description:    These files exist in every cpu's cache index directories.
+                There are currently 2 cache_disable_# files in each
+                directory.  Reading from these files on a supported
+                processor will return that cache disable index value
+                for that processor and node.  Writing to one of these
+                files will cause the specificed cache index to be disabled.
+
+                Currently, only AMD Family 10h Processors support cache index
+                disable, and only for their L3 caches.  See the BIOS and
+                Kernel Developer's Guide at
+                http://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/31116-Public-GH-BKDG_3.20_2-4-09.pdf
+                for formatting information and other details on the
+                cache index disable.
+Users:    joachim.deguara@amd.com