LIBPFM(3)

💖 LIBPFM(3) — the Linux Programmer's Manual glow-up 💖

okay bestie, welcome to the libpfm_intel_core page ✨ this is from the Linux Programmer's Manual, and it's all about making your Intel Core-based processors spill their performance-counter tea 🫖

🌸 NAME 🌸

libpfm_intel_core — support for Intel Core-based processors 💅

✨ SYNOPSIS ✨

#include <perfmon/pfmlib.h>

• PMU name: core
• PMU desc: Intel Core

🦋 DESCRIPTION 🦋

So the library is out here supporting every single Intel Core-based processor that exists, and that includes models 15, 23, and 29. all of them. no crumbs left. periodt 💜

🎀 MODIFIERS 🎀

these are the modifiers that are supported on Intel Core processors — collect them all, they're iconic:

• u — measure at user level, which includes privilege levels 1, 2, 3. this one corresponds to PFM_PLM3. it's a boolean modifier, so it's giving yes/no energy 🌸
• k — measure at kernel level, which includes privilege level 0. this one corresponds to PFM_PLM0. also a boolean modifier, keep up bestie 💫
• i — invert the meaning of the event. the counter will now count cycles in which the event is not occurring. literally flipping the whole vibe. this is a boolean modifier 🙈
• e — enable edge detection, i.e., count only when there is a state transition from no occurrence of the event to at least one occurrence. so it's the "something finally happened" detector 🔥

⚠️ okay so this modifier must be combined with a counter mask modifier (m) with a value greater or equal to one. do not skip this step, i'm begging 😭

this is a boolean modifier.

• c — set the counter mask value. the mask acts as a threshold. the counter will count the number of cycles in which the number of occurrences of the event is greater or equal to the threshold. it's giving "how many times do i have to see this before it counts" energy 👑

this is an integer modifier with values in the range [0:255] 💅

💌 AUTHORS 💌

Stephane Eranian <eranian@gmail.com> — the main character who made this happen 🫶👑

and that's the whole page bestie, no cap 🌈 September, 2009, from the Linux Programmer's Manual — LIBPFM(3), that's the source/version and the date right there, slay 💖✨🎀