691 lines
26 KiB
Plaintext
691 lines
26 KiB
Plaintext
What: /sys/devices/system/cpu/
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Date: pre-git history
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Contact: Linux kernel mailing list <linux-kernel@vger.kernel.org>
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Description:
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A collection of both global and individual CPU attributes
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Individual CPU attributes are contained in subdirectories
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named by the kernel's logical CPU number, e.g.:
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/sys/devices/system/cpu/cpuX/
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What: /sys/devices/system/cpu/kernel_max
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/sys/devices/system/cpu/offline
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/sys/devices/system/cpu/online
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/sys/devices/system/cpu/possible
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/sys/devices/system/cpu/present
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Date: December 2008
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Contact: Linux kernel mailing list <linux-kernel@vger.kernel.org>
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Description: CPU topology files that describe kernel limits related to
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hotplug. Briefly:
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kernel_max: the maximum cpu index allowed by the kernel
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configuration.
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offline: cpus that are not online because they have been
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HOTPLUGGED off or exceed the limit of cpus allowed by the
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kernel configuration (kernel_max above).
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online: cpus that are online and being scheduled.
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possible: cpus that have been allocated resources and can be
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brought online if they are present.
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present: cpus that have been identified as being present in
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the system.
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See Documentation/admin-guide/cputopology.rst for more information.
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What: /sys/devices/system/cpu/probe
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/sys/devices/system/cpu/release
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Date: November 2009
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Contact: Linux kernel mailing list <linux-kernel@vger.kernel.org>
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Description: Dynamic addition and removal of CPU's. This is not hotplug
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removal, this is meant complete removal/addition of the CPU
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from the system.
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probe: writes to this file will dynamically add a CPU to the
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system. Information written to the file to add CPU's is
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architecture specific.
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release: writes to this file dynamically remove a CPU from
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the system. Information written to the file to remove CPU's
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is architecture specific.
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What: /sys/devices/system/cpu/cpuX/node
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Date: October 2009
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Contact: Linux memory management mailing list <linux-mm@kvack.org>
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Description: Discover NUMA node a CPU belongs to
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When CONFIG_NUMA is enabled, a symbolic link that points
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to the corresponding NUMA node directory.
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For example, the following symlink is created for cpu42
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in NUMA node 2:
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/sys/devices/system/cpu/cpu42/node2 -> ../../node/node2
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What: /sys/devices/system/cpu/cpuX/topology/core_siblings
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/sys/devices/system/cpu/cpuX/topology/core_siblings_list
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/sys/devices/system/cpu/cpuX/topology/physical_package_id
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/sys/devices/system/cpu/cpuX/topology/thread_siblings
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/sys/devices/system/cpu/cpuX/topology/thread_siblings_list
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/sys/devices/system/cpu/cpuX/topology/ppin
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Date: December 2008
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Contact: Linux kernel mailing list <linux-kernel@vger.kernel.org>
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Description: CPU topology files that describe a logical CPU's relationship
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to other cores and threads in the same physical package.
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One cpuX directory is created per logical CPU in the system,
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e.g. /sys/devices/system/cpu/cpu42/.
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Briefly, the files above are:
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core_siblings: internal kernel map of cpuX's hardware threads
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within the same physical_package_id.
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core_siblings_list: human-readable list of the logical CPU
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numbers within the same physical_package_id as cpuX.
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physical_package_id: physical package id of cpuX. Typically
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corresponds to a physical socket number, but the actual value
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is architecture and platform dependent.
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thread_siblings: internal kernel map of cpuX's hardware
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threads within the same core as cpuX
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thread_siblings_list: human-readable list of cpuX's hardware
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threads within the same core as cpuX
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ppin: human-readable Protected Processor Identification
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Number of the socket the cpu# belongs to. There should be
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one per physical_package_id. File is readable only to
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admin.
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See Documentation/admin-guide/cputopology.rst for more information.
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What: /sys/devices/system/cpu/cpuidle/available_governors
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/sys/devices/system/cpu/cpuidle/current_driver
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/sys/devices/system/cpu/cpuidle/current_governor
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/sys/devices/system/cpu/cpuidle/current_governer_ro
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Date: September 2007
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Contact: Linux kernel mailing list <linux-kernel@vger.kernel.org>
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Description: Discover cpuidle policy and mechanism
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Various CPUs today support multiple idle levels that are
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differentiated by varying exit latencies and power
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consumption during idle.
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Idle policy (governor) is differentiated from idle mechanism
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(driver).
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available_governors: (RO) displays a space separated list of
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available governors.
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current_driver: (RO) displays current idle mechanism.
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current_governor: (RW) displays current idle policy. Users can
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switch the governor at runtime by writing to this file.
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current_governor_ro: (RO) displays current idle policy.
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See Documentation/admin-guide/pm/cpuidle.rst and
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Documentation/driver-api/pm/cpuidle.rst for more information.
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What: /sys/devices/system/cpu/cpuX/cpuidle/state<N>/name
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/sys/devices/system/cpu/cpuX/cpuidle/stateN/latency
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/sys/devices/system/cpu/cpuX/cpuidle/stateN/power
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/sys/devices/system/cpu/cpuX/cpuidle/stateN/time
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/sys/devices/system/cpu/cpuX/cpuidle/stateN/usage
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/sys/devices/system/cpu/cpuX/cpuidle/stateN/above
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/sys/devices/system/cpu/cpuX/cpuidle/stateN/below
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Date: September 2007
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KernelVersion: v2.6.24
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Contact: Linux power management list <linux-pm@vger.kernel.org>
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Description:
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The directory /sys/devices/system/cpu/cpuX/cpuidle contains per
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logical CPU specific cpuidle information for each online cpu X.
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The processor idle states which are available for use have the
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following attributes:
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======== ==== =================================================
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name: (RO) Name of the idle state (string).
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latency: (RO) The latency to exit out of this idle state (in
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microseconds).
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power: (RO) The power consumed while in this idle state (in
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milliwatts).
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time: (RO) The total time spent in this idle state
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(in microseconds).
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usage: (RO) Number of times this state was entered (a count).
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above: (RO) Number of times this state was entered, but the
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observed CPU idle duration was too short for it
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(a count).
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below: (RO) Number of times this state was entered, but the
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observed CPU idle duration was too long for it
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(a count).
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======== ==== =================================================
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What: /sys/devices/system/cpu/cpuX/cpuidle/state<N>/desc
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Date: February 2008
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KernelVersion: v2.6.25
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Contact: Linux power management list <linux-pm@vger.kernel.org>
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Description:
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(RO) A small description about the idle state (string).
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What: /sys/devices/system/cpu/cpuX/cpuidle/state<N>/disable
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Date: March 2012
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KernelVersion: v3.10
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Contact: Linux power management list <linux-pm@vger.kernel.org>
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Description:
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(RW) Option to disable this idle state (bool). The behavior and
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the effect of the disable variable depends on the implementation
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of a particular governor. In the ladder governor, for example,
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it is not coherent, i.e. if one is disabling a light state, then
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all deeper states are disabled as well, but the disable variable
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does not reflect it. Likewise, if one enables a deep state but a
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lighter state still is disabled, then this has no effect.
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What: /sys/devices/system/cpu/cpuX/cpuidle/state<N>/default_status
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Date: December 2019
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KernelVersion: v5.6
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Contact: Linux power management list <linux-pm@vger.kernel.org>
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Description:
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(RO) The default status of this state, "enabled" or "disabled".
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What: /sys/devices/system/cpu/cpuX/cpuidle/state<N>/residency
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Date: March 2014
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KernelVersion: v3.15
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Contact: Linux power management list <linux-pm@vger.kernel.org>
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Description:
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(RO) Display the target residency i.e. the minimum amount of
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time (in microseconds) this cpu should spend in this idle state
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to make the transition worth the effort.
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What: /sys/devices/system/cpu/cpuX/cpuidle/state<N>/s2idle/
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Date: March 2018
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KernelVersion: v4.17
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Contact: Linux power management list <linux-pm@vger.kernel.org>
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Description:
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Idle state usage statistics related to suspend-to-idle.
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This attribute group is only present for states that can be
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used in suspend-to-idle with suspended timekeeping.
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What: /sys/devices/system/cpu/cpuX/cpuidle/state<N>/s2idle/time
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Date: March 2018
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KernelVersion: v4.17
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Contact: Linux power management list <linux-pm@vger.kernel.org>
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Description:
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Total time spent by the CPU in suspend-to-idle (with scheduler
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tick suspended) after requesting this state.
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What: /sys/devices/system/cpu/cpuX/cpuidle/state<N>/s2idle/usage
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Date: March 2018
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KernelVersion: v4.17
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Contact: Linux power management list <linux-pm@vger.kernel.org>
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Description:
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Total number of times this state has been requested by the CPU
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while entering suspend-to-idle.
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What: /sys/devices/system/cpu/cpuX/cpufreq/*
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Date: pre-git history
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Contact: linux-pm@vger.kernel.org
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Description: Discover and change clock speed of CPUs
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Clock scaling allows you to change the clock speed of the
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CPUs on the fly. This is a nice method to save battery
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power, because the lower the clock speed, the less power
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the CPU consumes.
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There are many knobs to tweak in this directory.
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See files in Documentation/cpu-freq/ for more information.
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What: /sys/devices/system/cpu/cpuX/cpufreq/freqdomain_cpus
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Date: June 2013
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Contact: linux-pm@vger.kernel.org
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Description: Discover CPUs in the same CPU frequency coordination domain
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freqdomain_cpus is the list of CPUs (online+offline) that share
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the same clock/freq domain (possibly at the hardware level).
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That information may be hidden from the cpufreq core and the
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value of related_cpus may be different from freqdomain_cpus. This
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attribute is useful for user space DVFS controllers to get better
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power/performance results for platforms using acpi-cpufreq.
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This file is only present if the acpi-cpufreq or the cppc-cpufreq
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drivers are in use.
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What: /sys/devices/system/cpu/cpu*/cache/index3/cache_disable_{0,1}
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Date: August 2008
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KernelVersion: 2.6.27
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Contact: Linux kernel mailing list <linux-kernel@vger.kernel.org>
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Description: Disable L3 cache indices
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These files exist in every CPU's cache/index3 directory. Each
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cache_disable_{0,1} file corresponds to one disable slot which
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can be used to disable a cache index. Reading from these files
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on a processor with this functionality will return the currently
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disabled index for that node. There is one L3 structure per
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node, or per internal node on MCM machines. Writing a valid
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index to one of these files will cause the specified cache
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index to be disabled.
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All AMD processors with L3 caches provide this functionality.
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For details, see BKDGs at
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https://www.amd.com/en/support/tech-docs?keyword=bios+kernel
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What: /sys/devices/system/cpu/cpufreq/boost
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Date: August 2012
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Contact: Linux kernel mailing list <linux-kernel@vger.kernel.org>
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Description: Processor frequency boosting control
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This switch controls the boost setting for the whole system.
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Boosting allows the CPU and the firmware to run at a frequency
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beyond its nominal limit.
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More details can be found in
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Documentation/admin-guide/pm/cpufreq.rst
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What: /sys/devices/system/cpu/cpuX/crash_notes
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/sys/devices/system/cpu/cpuX/crash_notes_size
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Date: April 2013
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Contact: kexec@lists.infradead.org
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Description: address and size of the percpu note.
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crash_notes: the physical address of the memory that holds the
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note of cpuX.
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crash_notes_size: size of the note of cpuX.
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What: /sys/devices/system/cpu/intel_pstate/max_perf_pct
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/sys/devices/system/cpu/intel_pstate/min_perf_pct
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/sys/devices/system/cpu/intel_pstate/no_turbo
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Date: February 2013
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Contact: linux-pm@vger.kernel.org
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Description: Parameters for the Intel P-state driver
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Logic for selecting the current P-state in Intel
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Sandybridge+ processors. The three knobs control
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limits for the P-state that will be requested by the
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driver.
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max_perf_pct: limits the maximum P state that will be requested by
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the driver stated as a percentage of the available performance.
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min_perf_pct: limits the minimum P state that will be requested by
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the driver stated as a percentage of the available performance.
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no_turbo: limits the driver to selecting P states below the turbo
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frequency range.
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More details can be found in
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Documentation/admin-guide/pm/intel_pstate.rst
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What: /sys/devices/system/cpu/cpu*/cache/index*/<set_of_attributes_mentioned_below>
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Date: July 2014(documented, existed before August 2008)
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Contact: Sudeep Holla <sudeep.holla@arm.com>
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Linux kernel mailing list <linux-kernel@vger.kernel.org>
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Description: Parameters for the CPU cache attributes
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allocation_policy:
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- WriteAllocate:
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allocate a memory location to a cache line
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on a cache miss because of a write
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- ReadAllocate:
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allocate a memory location to a cache line
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on a cache miss because of a read
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- ReadWriteAllocate:
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both writeallocate and readallocate
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attributes:
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LEGACY used only on IA64 and is same as write_policy
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coherency_line_size:
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the minimum amount of data in bytes that gets
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transferred from memory to cache
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level:
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the cache hierarchy in the multi-level cache configuration
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number_of_sets:
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total number of sets in the cache, a set is a
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collection of cache lines with the same cache index
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physical_line_partition:
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number of physical cache line per cache tag
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shared_cpu_list:
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the list of logical cpus sharing the cache
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shared_cpu_map:
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logical cpu mask containing the list of cpus sharing
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the cache
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size:
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the total cache size in kB
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type:
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- Instruction: cache that only holds instructions
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- Data: cache that only caches data
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- Unified: cache that holds both data and instructions
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ways_of_associativity:
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degree of freedom in placing a particular block
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of memory in the cache
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write_policy:
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- WriteThrough:
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data is written to both the cache line
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and to the block in the lower-level memory
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- WriteBack:
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data is written only to the cache line and
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the modified cache line is written to main
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memory only when it is replaced
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What: /sys/devices/system/cpu/cpu*/cache/index*/id
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Date: September 2016
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Contact: Linux kernel mailing list <linux-kernel@vger.kernel.org>
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Description: Cache id
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The id provides a unique number for a specific instance of
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a cache of a particular type. E.g. there may be a level
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3 unified cache on each socket in a server and we may
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assign them ids 0, 1, 2, ...
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Note that id value can be non-contiguous. E.g. level 1
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caches typically exist per core, but there may not be a
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power of two cores on a socket, so these caches may be
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numbered 0, 1, 2, 3, 4, 5, 8, 9, 10, ...
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What: /sys/devices/system/cpu/cpuX/cpufreq/throttle_stats
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/sys/devices/system/cpu/cpuX/cpufreq/throttle_stats/turbo_stat
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/sys/devices/system/cpu/cpuX/cpufreq/throttle_stats/sub_turbo_stat
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/sys/devices/system/cpu/cpuX/cpufreq/throttle_stats/unthrottle
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/sys/devices/system/cpu/cpuX/cpufreq/throttle_stats/powercap
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/sys/devices/system/cpu/cpuX/cpufreq/throttle_stats/overtemp
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/sys/devices/system/cpu/cpuX/cpufreq/throttle_stats/supply_fault
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/sys/devices/system/cpu/cpuX/cpufreq/throttle_stats/overcurrent
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/sys/devices/system/cpu/cpuX/cpufreq/throttle_stats/occ_reset
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Date: March 2016
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Contact: Linux kernel mailing list <linux-kernel@vger.kernel.org>
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Linux for PowerPC mailing list <linuxppc-dev@ozlabs.org>
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Description: POWERNV CPUFreq driver's frequency throttle stats directory and
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attributes
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'cpuX/cpufreq/throttle_stats' directory contains the CPU frequency
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throttle stat attributes for the chip. The throttle stats of a cpu
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is common across all the cpus belonging to a chip. Below are the
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throttle attributes exported in the 'throttle_stats' directory:
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- turbo_stat : This file gives the total number of times the max
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frequency is throttled to lower frequency in turbo (at and above
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nominal frequency) range of frequencies.
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- sub_turbo_stat : This file gives the total number of times the
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max frequency is throttled to lower frequency in sub-turbo(below
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nominal frequency) range of frequencies.
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- unthrottle : This file gives the total number of times the max
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frequency is unthrottled after being throttled.
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- powercap : This file gives the total number of times the max
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frequency is throttled due to 'Power Capping'.
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- overtemp : This file gives the total number of times the max
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frequency is throttled due to 'CPU Over Temperature'.
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- supply_fault : This file gives the total number of times the
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max frequency is throttled due to 'Power Supply Failure'.
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- overcurrent : This file gives the total number of times the
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max frequency is throttled due to 'Overcurrent'.
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- occ_reset : This file gives the total number of times the max
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frequency is throttled due to 'OCC Reset'.
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The sysfs attributes representing different throttle reasons like
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powercap, overtemp, supply_fault, overcurrent and occ_reset map to
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the reasons provided by OCC firmware for throttling the frequency.
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What: /sys/devices/system/cpu/cpufreq/policyX/throttle_stats
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/sys/devices/system/cpu/cpufreq/policyX/throttle_stats/turbo_stat
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/sys/devices/system/cpu/cpufreq/policyX/throttle_stats/sub_turbo_stat
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/sys/devices/system/cpu/cpufreq/policyX/throttle_stats/unthrottle
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/sys/devices/system/cpu/cpufreq/policyX/throttle_stats/powercap
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/sys/devices/system/cpu/cpufreq/policyX/throttle_stats/overtemp
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/sys/devices/system/cpu/cpufreq/policyX/throttle_stats/supply_fault
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/sys/devices/system/cpu/cpufreq/policyX/throttle_stats/overcurrent
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/sys/devices/system/cpu/cpufreq/policyX/throttle_stats/occ_reset
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Date: March 2016
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Contact: Linux kernel mailing list <linux-kernel@vger.kernel.org>
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Linux for PowerPC mailing list <linuxppc-dev@ozlabs.org>
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Description: POWERNV CPUFreq driver's frequency throttle stats directory and
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attributes
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'policyX/throttle_stats' directory and all the attributes are same as
|
|
the /sys/devices/system/cpu/cpuX/cpufreq/throttle_stats directory and
|
|
attributes which give the frequency throttle information of the chip.
|
|
|
|
What: /sys/devices/system/cpu/cpuX/regs/
|
|
/sys/devices/system/cpu/cpuX/regs/identification/
|
|
/sys/devices/system/cpu/cpuX/regs/identification/midr_el1
|
|
/sys/devices/system/cpu/cpuX/regs/identification/revidr_el1
|
|
/sys/devices/system/cpu/cpuX/regs/identification/smidr_el1
|
|
Date: June 2016
|
|
Contact: Linux ARM Kernel Mailing list <linux-arm-kernel@lists.infradead.org>
|
|
Description: AArch64 CPU registers
|
|
|
|
'identification' directory exposes the CPU ID registers for
|
|
identifying model and revision of the CPU and SMCU.
|
|
|
|
What: /sys/devices/system/cpu/aarch32_el0
|
|
Date: May 2021
|
|
Contact: Linux ARM Kernel Mailing list <linux-arm-kernel@lists.infradead.org>
|
|
Description: Identifies the subset of CPUs in the system that can execute
|
|
AArch32 (32-bit ARM) applications. If present, the same format as
|
|
/sys/devices/system/cpu/{offline,online,possible,present} is used.
|
|
If absent, then all or none of the CPUs can execute AArch32
|
|
applications and execve() will behave accordingly.
|
|
|
|
What: /sys/devices/system/cpu/cpuX/cpu_capacity
|
|
Date: December 2016
|
|
Contact: Linux kernel mailing list <linux-kernel@vger.kernel.org>
|
|
Description: information about CPUs heterogeneity.
|
|
|
|
cpu_capacity: capacity of cpuX.
|
|
|
|
What: /sys/devices/system/cpu/vulnerabilities
|
|
/sys/devices/system/cpu/vulnerabilities/gather_data_sampling
|
|
/sys/devices/system/cpu/vulnerabilities/itlb_multihit
|
|
/sys/devices/system/cpu/vulnerabilities/l1tf
|
|
/sys/devices/system/cpu/vulnerabilities/mds
|
|
/sys/devices/system/cpu/vulnerabilities/meltdown
|
|
/sys/devices/system/cpu/vulnerabilities/mmio_stale_data
|
|
/sys/devices/system/cpu/vulnerabilities/reg_file_data_sampling
|
|
/sys/devices/system/cpu/vulnerabilities/retbleed
|
|
/sys/devices/system/cpu/vulnerabilities/spec_store_bypass
|
|
/sys/devices/system/cpu/vulnerabilities/spectre_v1
|
|
/sys/devices/system/cpu/vulnerabilities/spectre_v2
|
|
/sys/devices/system/cpu/vulnerabilities/srbds
|
|
/sys/devices/system/cpu/vulnerabilities/tsx_async_abort
|
|
Date: January 2018
|
|
Contact: Linux kernel mailing list <linux-kernel@vger.kernel.org>
|
|
Description: Information about CPU vulnerabilities
|
|
|
|
The files are named after the code names of CPU
|
|
vulnerabilities. The output of those files reflects the
|
|
state of the CPUs in the system. Possible output values:
|
|
|
|
================ ==============================================
|
|
"Not affected" CPU is not affected by the vulnerability
|
|
"Vulnerable" CPU is affected and no mitigation in effect
|
|
"Mitigation: $M" CPU is affected and mitigation $M is in effect
|
|
================ ==============================================
|
|
|
|
See also: Documentation/admin-guide/hw-vuln/index.rst
|
|
|
|
What: /sys/devices/system/cpu/smt
|
|
/sys/devices/system/cpu/smt/active
|
|
/sys/devices/system/cpu/smt/control
|
|
Date: June 2018
|
|
Contact: Linux kernel mailing list <linux-kernel@vger.kernel.org>
|
|
Description: Control Symmetric Multi Threading (SMT)
|
|
|
|
active: Tells whether SMT is active (enabled and siblings online)
|
|
|
|
control: Read/write interface to control SMT. Possible
|
|
values:
|
|
|
|
================ =========================================
|
|
"on" SMT is enabled
|
|
"off" SMT is disabled
|
|
"forceoff" SMT is force disabled. Cannot be changed.
|
|
"notsupported" SMT is not supported by the CPU
|
|
"notimplemented" SMT runtime toggling is not
|
|
implemented for the architecture
|
|
================ =========================================
|
|
|
|
If control status is "forceoff" or "notsupported" writes
|
|
are rejected.
|
|
|
|
What: /sys/devices/system/cpu/cpuX/power/energy_perf_bias
|
|
Date: March 2019
|
|
Contact: linux-pm@vger.kernel.org
|
|
Description: Intel Energy and Performance Bias Hint (EPB)
|
|
|
|
EPB for the given CPU in a sliding scale 0 - 15, where a value
|
|
of 0 corresponds to a hint preference for highest performance
|
|
and a value of 15 corresponds to the maximum energy savings.
|
|
|
|
In order to change the EPB value for the CPU, write either
|
|
a number in the 0 - 15 sliding scale above, or one of the
|
|
strings: "performance", "balance-performance", "normal",
|
|
"balance-power", "power" (that represent values reflected by
|
|
their meaning), to this attribute.
|
|
|
|
This attribute is present for all online CPUs supporting the
|
|
Intel EPB feature.
|
|
|
|
What: /sys/devices/system/cpu/umwait_control
|
|
/sys/devices/system/cpu/umwait_control/enable_c02
|
|
/sys/devices/system/cpu/umwait_control/max_time
|
|
Date: May 2019
|
|
Contact: Linux kernel mailing list <linux-kernel@vger.kernel.org>
|
|
Description: Umwait control
|
|
|
|
enable_c02: Read/write interface to control umwait C0.2 state
|
|
Read returns C0.2 state status:
|
|
0: C0.2 is disabled
|
|
1: C0.2 is enabled
|
|
|
|
Write 'y' or '1' or 'on' to enable C0.2 state.
|
|
Write 'n' or '0' or 'off' to disable C0.2 state.
|
|
|
|
The interface is case insensitive.
|
|
|
|
max_time: Read/write interface to control umwait maximum time
|
|
in TSC-quanta that the CPU can reside in either C0.1
|
|
or C0.2 state. The time is an unsigned 32-bit number.
|
|
Note that a value of zero means there is no limit.
|
|
Low order two bits must be zero.
|
|
|
|
What: /sys/devices/system/cpu/svm
|
|
Date: August 2019
|
|
Contact: Linux kernel mailing list <linux-kernel@vger.kernel.org>
|
|
Linux for PowerPC mailing list <linuxppc-dev@ozlabs.org>
|
|
Description: Secure Virtual Machine
|
|
|
|
If 1, it means the system is using the Protected Execution
|
|
Facility in POWER9 and newer processors. i.e., it is a Secure
|
|
Virtual Machine.
|
|
|
|
What: /sys/devices/system/cpu/cpuX/purr
|
|
Date: Apr 2005
|
|
Contact: Linux for PowerPC mailing list <linuxppc-dev@ozlabs.org>
|
|
Description: PURR ticks for this CPU since the system boot.
|
|
|
|
The Processor Utilization Resources Register (PURR) is
|
|
a 64-bit counter which provides an estimate of the
|
|
resources used by the CPU thread. The contents of this
|
|
register increases monotonically. This sysfs interface
|
|
exposes the number of PURR ticks for cpuX.
|
|
|
|
What: /sys/devices/system/cpu/cpuX/spurr
|
|
Date: Dec 2006
|
|
Contact: Linux for PowerPC mailing list <linuxppc-dev@ozlabs.org>
|
|
Description: SPURR ticks for this CPU since the system boot.
|
|
|
|
The Scaled Processor Utilization Resources Register
|
|
(SPURR) is a 64-bit counter that provides a frequency
|
|
invariant estimate of the resources used by the CPU
|
|
thread. The contents of this register increases
|
|
monotonically. This sysfs interface exposes the number
|
|
of SPURR ticks for cpuX.
|
|
|
|
What: /sys/devices/system/cpu/cpuX/idle_purr
|
|
Date: Apr 2020
|
|
Contact: Linux for PowerPC mailing list <linuxppc-dev@ozlabs.org>
|
|
Description: PURR ticks for cpuX when it was idle.
|
|
|
|
This sysfs interface exposes the number of PURR ticks
|
|
for cpuX when it was idle.
|
|
|
|
What: /sys/devices/system/cpu/cpuX/idle_spurr
|
|
Date: Apr 2020
|
|
Contact: Linux for PowerPC mailing list <linuxppc-dev@ozlabs.org>
|
|
Description: SPURR ticks for cpuX when it was idle.
|
|
|
|
This sysfs interface exposes the number of SPURR ticks
|
|
for cpuX when it was idle.
|
|
|
|
What: /sys/devices/system/cpu/cpuX/mte_tcf_preferred
|
|
Date: July 2021
|
|
Contact: Linux ARM Kernel Mailing list <linux-arm-kernel@lists.infradead.org>
|
|
Description: Preferred MTE tag checking mode
|
|
|
|
When a user program specifies more than one MTE tag checking
|
|
mode, this sysfs node is used to specify which mode should
|
|
be preferred when scheduling a task on that CPU. Possible
|
|
values:
|
|
|
|
================ ==============================================
|
|
"sync" Prefer synchronous mode
|
|
"asymm" Prefer asymmetric mode
|
|
"async" Prefer asynchronous mode
|
|
================ ==============================================
|
|
|
|
See also: Documentation/arm64/memory-tagging-extension.rst
|
|
|
|
What: /sys/devices/system/cpu/nohz_full
|
|
Date: Apr 2015
|
|
Contact: Linux kernel mailing list <linux-kernel@vger.kernel.org>
|
|
Description:
|
|
(RO) the list of CPUs that are in nohz_full mode.
|
|
These CPUs are set by boot parameter "nohz_full=".
|
|
|
|
What: /sys/devices/system/cpu/isolated
|
|
Date: Apr 2015
|
|
Contact: Linux kernel mailing list <linux-kernel@vger.kernel.org>
|
|
Description:
|
|
(RO) the list of CPUs that are isolated and don't
|
|
participate in load balancing. These CPUs are set by
|
|
boot parameter "isolcpus=".
|