diff options
Diffstat (limited to 'Documentation/ABI/testing/sysfs-devices-system-cpu')
| -rw-r--r-- | Documentation/ABI/testing/sysfs-devices-system-cpu | 138 |
1 files changed, 120 insertions, 18 deletions
diff --git a/Documentation/ABI/testing/sysfs-devices-system-cpu b/Documentation/ABI/testing/sysfs-devices-system-cpu index ecd585ca2d50..3a05604c21bf 100644 --- a/Documentation/ABI/testing/sysfs-devices-system-cpu +++ b/Documentation/ABI/testing/sysfs-devices-system-cpu @@ -111,6 +111,7 @@ What: /sys/devices/system/cpu/cpuidle/available_governors /sys/devices/system/cpu/cpuidle/current_driver /sys/devices/system/cpu/cpuidle/current_governor /sys/devices/system/cpu/cpuidle/current_governer_ro + /sys/devices/system/cpu/cpuidle/intel_c1_demotion Date: September 2007 Contact: Linux kernel mailing list <linux-kernel@vger.kernel.org> Description: Discover cpuidle policy and mechanism @@ -132,7 +133,11 @@ Description: Discover cpuidle policy and mechanism current_governor_ro: (RO) displays current idle policy. - See Documentation/admin-guide/pm/cpuidle.rst and + intel_c1_demotion: (RW) enables/disables the C1 demotion + feature on Intel CPUs. + + See Documentation/admin-guide/pm/cpuidle.rst, + Documentation/admin-guide/pm/intel_idle.rst, and Documentation/driver-api/pm/cpuidle.rst for more information. @@ -268,6 +273,60 @@ Description: Discover CPUs in the same CPU frequency coordination domain This file is only present if the acpi-cpufreq or the cppc-cpufreq drivers are in use. +What: /sys/devices/system/cpu/cpuX/cpufreq/auto_select +Date: May 2025 +Contact: linux-pm@vger.kernel.org +Description: Autonomous selection enable + + Read/write interface to control autonomous selection enable + Read returns autonomous selection status: + 0: autonomous selection is disabled + 1: autonomous selection is enabled + + Write 'y' or '1' or 'on' to enable autonomous selection. + Write 'n' or '0' or 'off' to disable autonomous selection. + + This file is only present if the cppc-cpufreq driver is in use. + +What: /sys/devices/system/cpu/cpuX/cpufreq/auto_act_window +Date: May 2025 +Contact: linux-pm@vger.kernel.org +Description: Autonomous activity window + + This file indicates a moving utilization sensitivity window to + the platform's autonomous selection policy. + + Read/write an integer represents autonomous activity window (in + microseconds) from/to this file. The max value to write is + 1270000000 but the max significand is 127. This means that if 128 + is written to this file, 127 will be stored. If the value is + greater than 130, only the first two digits will be saved as + significand. + + Writing a zero value to this file enable the platform to + determine an appropriate Activity Window depending on the workload. + + Writing to this file only has meaning when Autonomous Selection is + enabled. + + This file is only present if the cppc-cpufreq driver is in use. + +What: /sys/devices/system/cpu/cpuX/cpufreq/energy_performance_preference_val +Date: May 2025 +Contact: linux-pm@vger.kernel.org +Description: Energy performance preference + + Read/write an 8-bit integer from/to this file. This file + represents a range of values from 0 (performance preference) to + 0xFF (energy efficiency preference) that influences the rate of + performance increase/decrease and the result of the hardware's + energy efficiency and performance optimization policies. + + Writing to this file only has meaning when Autonomous Selection is + enabled. + + This file is only present if the cppc-cpufreq driver is in use. + What: /sys/devices/system/cpu/cpu*/cache/index3/cache_disable_{0,1} Date: August 2008 @@ -354,9 +413,6 @@ Description: Parameters for the CPU cache attributes - ReadWriteAllocate: both writeallocate and readallocate - attributes: - LEGACY used only on IA64 and is same as write_policy - coherency_line_size: the minimum amount of data in bytes that gets transferred from memory to cache @@ -426,7 +482,7 @@ What: /sys/devices/system/cpu/cpuX/cpufreq/throttle_stats /sys/devices/system/cpu/cpuX/cpufreq/throttle_stats/occ_reset Date: March 2016 Contact: Linux kernel mailing list <linux-kernel@vger.kernel.org> - Linux for PowerPC mailing list <linuxppc-dev@ozlabs.org> + Linux for PowerPC mailing list <linuxppc-dev@lists.ozlabs.org> Description: POWERNV CPUFreq driver's frequency throttle stats directory and attributes @@ -476,7 +532,7 @@ What: /sys/devices/system/cpu/cpufreq/policyX/throttle_stats /sys/devices/system/cpu/cpufreq/policyX/throttle_stats/occ_reset Date: March 2016 Contact: Linux kernel mailing list <linux-kernel@vger.kernel.org> - Linux for PowerPC mailing list <linuxppc-dev@ozlabs.org> + Linux for PowerPC mailing list <linuxppc-dev@lists.ozlabs.org> Description: POWERNV CPUFreq driver's frequency throttle stats directory and attributes @@ -488,6 +544,7 @@ 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/aidr_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> @@ -513,17 +570,23 @@ 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/indirect_target_selection + /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/old_microcode + /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/spec_store_bypass - /sys/devices/system/cpu/vulnerabilities/l1tf - /sys/devices/system/cpu/vulnerabilities/mds /sys/devices/system/cpu/vulnerabilities/srbds + /sys/devices/system/cpu/vulnerabilities/tsa /sys/devices/system/cpu/vulnerabilities/tsx_async_abort - /sys/devices/system/cpu/vulnerabilities/itlb_multihit - /sys/devices/system/cpu/vulnerabilities/mmio_stale_data - /sys/devices/system/cpu/vulnerabilities/retbleed + /sys/devices/system/cpu/vulnerabilities/vmscape Date: January 2018 Contact: Linux kernel mailing list <linux-kernel@vger.kernel.org> Description: Information about CPU vulnerabilities @@ -555,6 +618,7 @@ Description: Control Symmetric Multi Threading (SMT) ================ ========================================= "on" SMT is enabled "off" SMT is disabled + "<N>" SMT is enabled with N threads per core. "forceoff" SMT is force disabled. Cannot be changed. "notsupported" SMT is not supported by the CPU "notimplemented" SMT runtime toggling is not @@ -562,7 +626,8 @@ Description: Control Symmetric Multi Threading (SMT) ================ ========================================= If control status is "forceoff" or "notsupported" writes - are rejected. + are rejected. Note that enabling SMT on PowerPC skips + offline cores. What: /sys/devices/system/cpu/cpuX/power/energy_perf_bias Date: March 2019 @@ -605,10 +670,22 @@ Description: Umwait control Note that a value of zero means there is no limit. Low order two bits must be zero. +What: /sys/devices/system/cpu/sev + /sys/devices/system/cpu/sev/vmpl +Date: May 2024 +Contact: Linux kernel mailing list <linux-kernel@vger.kernel.org> +Description: Secure Encrypted Virtualization (SEV) information + + This directory is only present when running as an SEV-SNP guest. + + vmpl: Reports the Virtual Machine Privilege Level (VMPL) at which + the SEV-SNP guest is running. + + 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> + Linux for PowerPC mailing list <linuxppc-dev@lists.ozlabs.org> Description: Secure Virtual Machine If 1, it means the system is using the Protected Execution @@ -617,7 +694,7 @@ Description: Secure Virtual Machine What: /sys/devices/system/cpu/cpuX/purr Date: Apr 2005 -Contact: Linux for PowerPC mailing list <linuxppc-dev@ozlabs.org> +Contact: Linux for PowerPC mailing list <linuxppc-dev@lists.ozlabs.org> Description: PURR ticks for this CPU since the system boot. The Processor Utilization Resources Register (PURR) is @@ -628,7 +705,7 @@ Description: PURR ticks for this CPU since the system boot. What: /sys/devices/system/cpu/cpuX/spurr Date: Dec 2006 -Contact: Linux for PowerPC mailing list <linuxppc-dev@ozlabs.org> +Contact: Linux for PowerPC mailing list <linuxppc-dev@lists.ozlabs.org> Description: SPURR ticks for this CPU since the system boot. The Scaled Processor Utilization Resources Register @@ -640,7 +717,7 @@ Description: SPURR ticks for this CPU since the system boot. What: /sys/devices/system/cpu/cpuX/idle_purr Date: Apr 2020 -Contact: Linux for PowerPC mailing list <linuxppc-dev@ozlabs.org> +Contact: Linux for PowerPC mailing list <linuxppc-dev@lists.ozlabs.org> Description: PURR ticks for cpuX when it was idle. This sysfs interface exposes the number of PURR ticks @@ -648,7 +725,7 @@ Description: 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> +Contact: Linux for PowerPC mailing list <linuxppc-dev@lists.ozlabs.org> Description: SPURR ticks for cpuX when it was idle. This sysfs interface exposes the number of SPURR ticks @@ -686,3 +763,28 @@ Description: (RO) the list of CPUs that are isolated and don't participate in load balancing. These CPUs are set by boot parameter "isolcpus=". + +What: /sys/devices/system/cpu/housekeeping +Date: Oct 2025 +Contact: Linux kernel mailing list <linux-kernel@vger.kernel.org> +Description: + (RO) the list of logical CPUs that are designated by the kernel as + "housekeeping". Each CPU are responsible for handling essential + system-wide background tasks, including RCU callbacks, delayed + timer callbacks, and unbound workqueues, minimizing scheduling + jitter on low-latency, isolated CPUs. These CPUs are set when boot + parameter "isolcpus=nohz" or "nohz_full=" is specified. + +What: /sys/devices/system/cpu/crash_hotplug +Date: Aug 2023 +Contact: Linux kernel mailing list <linux-kernel@vger.kernel.org> +Description: + (RO) indicates whether or not the kernel updates relevant kexec + segments on memory hot un/plug and/or on/offline events, avoiding the + need to reload kdump kernel. + +What: /sys/devices/system/cpu/enabled +Date: Nov 2022 +Contact: Linux kernel mailing list <linux-kernel@vger.kernel.org> +Description: + (RO) the list of CPUs that can be brought online. |