linux/tools/power/cpupower/lib, branch master

tools/power cpupower: Reset errno before strtoull()

2025-12-15T19:33:28Z

cpuidle_state_get_one_value() never cleared errno before calling strtoull(), so a prior ERANGE caused every cpuidle counter read to return zero. Reset errno to 0 before the conversion so each sysfs read is evaluated independently. Link: https://lore.kernel.org/r/20251201121745.3776703-1-kaushlendra.kumar@intel.com Signed-off-by: Kaushlendra Kumar Signed-off-by: Shuah Khan

tools/cpupower: Use strcspn() to strip trailing newline

2025-12-15T19:33:28Z

Replace manual newline removal with strcspn() which is safer and cleaner. This avoids potential out-of-bounds access on empty strings and handles the case where no newline exists. Link: https://lore.kernel.org/r/20251127044536.715722-1-kaushlendra.kumar@intel.com Signed-off-by: Kaushlendra Kumar Signed-off-by: Shuah Khan

tools/cpupower: Fix incorrect size in cpuidle_state_disable()

2025-09-24T23:15:35Z

Fix incorrect size parameter passed to cpuidle_state_write_file() in cpuidle_state_disable(). The function was incorrectly using sizeof(disable) which returns the size of the unsigned int variable (4 bytes) instead of the actual length of the string stored in the 'value' buffer. Since 'value' is populated with snprintf() to contain the string representation of the disable value, we should use the length returned by snprintf() to get the correct string length for writing to the sysfs file. This ensures the correct number of bytes is written to the cpuidle state disable file in sysfs. Link: https://lore.kernel.org/r/20250917050820.1785377-1-kaushlendra.kumar@intel.com Signed-off-by: Kaushlendra Kumar Signed-off-by: Shuah Khan

tools/cpupower: fix error return value in cpupower_write_sysfs()

2025-09-16T22:21:50Z

The cpupower_write_sysfs() function currently returns -1 on write failure, but the function signature indicates it should return an unsigned int. Returning -1 from an unsigned function results in a large positive value rather than indicating an error condition. Fix this by returning 0 on failure, which is more appropriate for an unsigned return type and maintains consistency with typical success/failure semantics where 0 indicates failure and non-zero indicates success (bytes written). Link: https://lore.kernel.org/r/20250828063000.803229-1-kaushlendra.kumar@intel.com Signed-off-by: Kaushlendra Kumar Signed-off-by: Shuah Khan

cpupower: Implement CPU physical core querying

2025-03-06T20:27:57Z

This patch is also an issue report. get_cpu_topology will always save into cpupower_topology a cores size of 0. The code to handle this looks like it was commented out, and what is commented out is missing a curly bracket. https://elixir.bootlin.com/linux/v6.13.5/source/tools/power/cpupower/lib/cpupower.c#L206-L212 Inspiration was taken from psutil to implement this by querying core_cpu_list. Instead of using a hashmap, I used a sorted array, and counted the number of valid unique strings. The counting of this takes place before the qsort for .pkg as the following code says it is dependent on the order of that sort. The previous code claimed Intel CPUs are not numbered correctly. I was not able to reproduce that issue and removed that comment and the code. This commit was tested with the libcpupower SWIG Python bindings and performed correctly on 4 different setups. The most notable is the Framework Intel laptop; a hybrid system of 4 P cores (8 threads) and 8 E cores (8 threads). The 4 setups: A 4 core virt-manager VM running Fedora 41 4c/4t (specs not listed) was tested as a sanity test for VMs. A Lenovo Ryzen 7 Pro 7840HS 8c/16t. A Supermico Intel(R) Xeon(R) Gold 6330 CPU w/ 56c/112t with 2 CPU sockets. A Framework 12th Gen Intel(R) Core(TM) i5-1240P with hybrid cores. CPU(s): 16 On-line CPU(s) list: 0-15 Vendor ID: AuthenticAMD Model name: AMD Ryzen 7 PRO 7840HS w/ Radeon 780M Graphics CPU family: 25 Model: 116 Thread(s) per core: 2 Core(s) per socket: 8 Socket(s): 1 Stepping: 1 CPU(s): 112 On-line CPU(s) list: 0-111 Vendor ID: GenuineIntel BIOS Vendor ID: Intel(R) Corporation Model name: Intel(R) Xeon(R) Gold 6330 CPU @ 2.00GHz BIOS Model name: Intel(R) Xeon(R) Gold 6330 CPU @ 2.00GHz CPU @ 2.0GHz BIOS CPU family: 179 CPU family: 6 Model: 106 Thread(s) per core: 2 Core(s) per socket: 28 Socket(s): 2 Stepping: 6 CPU(s): 16 On-line CPU(s) list: 0-15 Vendor ID: GenuineIntel Model name: 12th Gen Intel(R) Core(TM) i5-1240P CPU family: 6 Model: 154 Thread(s) per core: 2 Core(s) per socket: 12 Socket(s): 1 Stepping: 3 Link: https://lore.kernel.org/r/20250305210901.24177-1-jwyatt@redhat.com Signed-off-by: "John B. Wyatt IV" Signed-off-by: "John B. Wyatt IV" Signed-off-by: Shuah Khan

cpupower: Add support for showing energy performance preference

2024-12-20T16:12:07Z

The EPP value is useful for characterization of performance. Show it in cpupower frequency-info output. Link: https://lore.kernel.org/r/20241218191144.3440854-6-superm1@kernel.org Signed-off-by: Mario Limonciello Signed-off-by: Shuah Khan

cpupower: Add support for parsing 'enabled' or 'disabled' strings from table

2024-12-20T16:12:07Z

When cpufreq_get_sysfs_value_from_table() is passed a table with kernel strings that report 'enabled' or 'disabled' it always returns 0 because these can't cleanly convert to integers. Explicitly look for enabled or disabled strings from the kernel to handle this. Link: https://lore.kernel.org/r/20241218191144.3440854-3-superm1@kernel.org Signed-off-by: Mario Limonciello Signed-off-by: Shuah Khan

pm:cpupower: Add missing powercap_set_enabled() stub function

2024-09-06T00:48:57Z

There was a symbol listed in the powercap.h file that was not implemented. Implement it with a stub return of 0. Programs like SWIG require that functions that are defined in the headers be implemented. Fixes: c2294c1496b7 ("cpupower: Introduce powercap intel-rapl library and powercap-info command") Suggested-by: Shuah Khan Signed-off-by: John B. Wyatt IV Signed-off-by: John B. Wyatt IV Signed-off-by: Shuah Khan

tools/cpupower: display residency value in idle-info

2024-08-09T16:32:33Z

Update cpuidle tool to display the residency value of cpuidle states. This addition provides a clearer and more detailed view of idle state information when using cpuidle-info. -------------------------------- Before Patch: -------------------------------- $ cpupower idle-info CPUidle driver: intel_idle CPUidle governor: menu analyzing CPU 28: Number of idle states: 3 Available idle states: POLL C1 C1E POLL: Flags/Description: CPUIDLE CORE POLL IDLE Latency: 0 Usage: 7448 Duration: 207170 C1: Flags/Description: MWAIT 0x00 Latency: 2 Usage: 7023 Duration: 3736853 C1E: Flags/Description: MWAIT 0x01 Latency: 10 Usage: 18468 Duration: 11396212 -------------------------------- After Patch: -------------------------------- $ cpupower idle-info CPUidle driver: intel_idle CPUidle governor: menu analyzing CPU 12: Number of idle states: 3 Available idle states: POLL C1 C1E POLL: Flags/Description: CPUIDLE CORE POLL IDLE Latency: 0 Residency: 0 Usage: 1950 Duration: 38458 C1: Flags/Description: MWAIT 0x00 Latency: 2 Residency: 2 Usage: 10688 Duration: 7133020 C1E: Flags/Description: MWAIT 0x01 Latency: 10 Residency: 20 Usage: 22356 Duration: 15687259 -------------------------------- Signed-off-by: Aboorva Devarajan Signed-off-by: Shuah Khan

cpupower: Add is_valid_path API

2023-07-18T22:06:44Z

Add is_valid_path API to check whether the sysfs file is present or not. Suggested-by: Gautham R. Shenoy Reviewed-by: Mario Limonciello Signed-off-by: Wyes Karny Tested-by: Perry Yuan Acked-by: Huang Rui Signed-off-by: Shuah Khan