LIBPFM(3)

💖 libpfm_intel_wsm_unc 💖

okay bestie, welcome to the Linux Programmer's Manual, section LIBPFM(3) 🎀 — this is the page for libpfm_intel_wsm_unc, and it's giving "support for Intel Westmere uncore PMU" ✨ pull up a chair, we're learning today.

✨ NAME ✨

libpfm_intel_wsm_unc — support for Intel Westmere uncore PMU 🦋

✨ SYNOPSIS ✨

#include <perfmon/pfmlib.h>

PMU name: wsm_unc
PMU desc: Intel Westmere uncore

so those two little lines at the bottom there? that's literally the PMU's whole identity card. wsm_unc is the name you'll be typing, and "Intel Westmere uncore" is the glow-up description. 💅

🌸 DESCRIPTION 🌸

The library supports the Intel Westmere uncore PMU, as implemented by processors such as Intel Core i7 and Intel Core i5 — specifically models 37 and 44. 👑

This PMU is located at the socket-level, which means it's shared between the various cores. Not a private little counter for one core, no — it's the communal one everybody's using. And by construction it can only measure at all privilege levels. No privilege-level filtering for this one, it's all or nothing, periodt. 🫶

💅 MODIFIERS 💅

The following modifiers are supported on Intel Westmere processors — these are your little add-ons, your accessories for the event, iykyk:

• i — Invert the meaning of the event. The counter will now count cycles in which the event is not occurring. This is a boolean modifier. so like, uno-reverse card for your counter 🔄
• e — Enable edge detection, i.e., count only when there is a state transition. This is a boolean modifier. only the glow-ups get counted, not the steady state ✨
• 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. This is an integer modifier with values in the range [0:255]. 📏
• o — Causes the queue occupancy counter associated with the event to be cleared (zeroed). This is a boolean modifier. fresh start, clean slate, main character reset 🧚

👑 AUTHORS 👑

Stephane Eranian <eranian@gmail.com> — thank you for your service, legend 🫡💜

and that's the whole page, bestie! this one shipped as part of the Linux Programmer's Manual back in February, 2010, and it lives at LIBPFM(3). go measure something uncore-y. no cap. 🌈⭐💖