linux/tools/power/cpupower/lib/cpupower.h
John B. Wyatt IV f89cb9cba7 cpupower: Implement CPU physical core querying
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" <jwyatt@redhat.com>
Signed-off-by: "John B. Wyatt IV" <sageofredondo@gmail.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2025-03-06 13:27:57 -07:00

39 lines
799 B
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __CPUPOWER_CPUPOWER_H__
#define __CPUPOWER_CPUPOWER_H__
#define CPULIST_BUFFER 5
struct cpupower_topology {
/* Amount of CPU cores, packages and threads per core in the system */
unsigned int cores;
unsigned int pkgs;
unsigned int threads; /* per core */
/* Array gets mallocated with cores entries, holding per core info */
struct cpuid_core_info *core_info;
};
struct cpuid_core_info {
int pkg;
int core;
int cpu;
char core_cpu_list[CPULIST_BUFFER];
/* flags */
unsigned int is_online:1;
};
#ifdef __cplusplus
extern "C" {
#endif
int get_cpu_topology(struct cpupower_topology *cpu_top);
void cpu_topology_release(struct cpupower_topology cpu_top);
int cpupower_is_cpu_online(unsigned int cpu);
#ifdef __cplusplus
}
#endif
#endif