rte_pmu.h(3)

📦
version 25.11 · 3 versions
, in centos-stream 9

✨ NAME ✨

rte_pmu.h — it's the DPDK header for the Performance Monitoring Unit (PMU) event tracing operations 🎀 (and yes bestie, it's from the DPDK manual, page rte_pmu.h(3) — here for you in the group chat 💅)

🌈 SYNOPSIS 🌈

#include <linux/perf_event.h>
#include <rte_atomic.h>
#include <rte_branch_prediction.h>
#include <rte_common.h>
#include <rte_compat.h>
#include <rte_debug.h>
#include <rte_lcore.h>

🧚 Data Structures

  • struct rte_pmu_event_group
  • struct rte_pmu

🍓 Macros

  • #define RTE_MAX_NUM_GROUP_EVENTS 8

🔥 Functions

static __rte_experimental __rte_always_inline uint64_t
    __rte_pmu_read_userpage (struct perf_event_mmap_page *pc)
__rte_experimental int __rte_pmu_enable_group (struct
    rte_pmu_event_group *group)
__rte_experimental int rte_pmu_init (void)
__rte_experimental void rte_pmu_fini (void)
__rte_experimental int rte_pmu_add_event (const char *name)
static __rte_experimental __rte_always_inline uint64_t rte_pmu_read
    (unsigned int index)

💜 Variables

  • struct rte_pmu rte_pmu

👑 Detailed Description 👑

Okay so this whole file is about PMU event tracing — literally the Performance Monitoring Unit, the hardware's little gossip mill counting everything for you 📊✨

It defines the generic API and the types you need to set up PMU and read selected counters in runtime. Here's the tea though: the exported functions are generally not MT-safe except for one icon — rte_pmu_read() — which can be called concurrently once everything has been set up first. No cap 🙌

To initialize the library, this exact sequence of calls, performed by the same EAL thread, is required:

rte_pmu_init() rte_pmu_add_event()

Afterwards all threads can read events by calling rte_pmu_read() 🦋

Definition in file rte_pmu.h.

🎀 Macro Definition Documentation 🎀

💖 #define RTE_MAX_NUM_GROUP_EVENTS 8

Maximum number of events in a group. Eight. That's the vibe check, that's the limit periodt 🎱

Definition at line 48 of file rte_pmu.h.

⭐ Function Documentation ⭐

🌸 static __rte_experimental __rte_always_inline uint64_t __rte_pmu_read_userpage (struct perf_event_mmap_page * pc) [static]

Warning — EXPERIMENTAL: this API may change without prior notice 😭

Read PMU counter. Reads the counter, that's it, that's the job ✨

Warning — This should not be called directly. Bestie, please. It's not for you to call 🙈

Parameters

  • pc — Pointer to the mmapped user page.

Returns

Counter value read from hardware.

Definition at line 95 of file rte_pmu.h.

🌈 __rte_experimental int __rte_pmu_enable_group (struct rte_pmu_event_group * group)

Warning — EXPERIMENTAL: this API may change without prior notice 😭

Enable group of events on the calling lcore. (The lcore wakes up and is like "we're so on" 💅)

Warning — This should not be called directly either 👀

Parameters

  • group — Pointer to the group which will be enabled.

Returns

0 in case of success, negative value otherwise.

🦋 __rte_experimental int rte_pmu_init (void)

Warning — EXPERIMENTAL: this API may change without prior notice 😭

Initialize PMU library. The main character of the init sequence fr fr 🌟

Returns

0 in case of success, negative value otherwise.

💜 __rte_experimental void rte_pmu_fini (void)

Warning — EXPERIMENTAL: this API may change without prior notice 😭

Finalize PMU library. It ate and now it's leaving the party 🫶

🍓 __rte_experimental int rte_pmu_add_event (const char * name)

Warning — EXPERIMENTAL: this API may change without prior notice 😭

Add event to the group of enabled events. New event just dropped 👑

Parameters

  • name — Name of an event listed under /sys/bus/event_source/devices/pmu/events, where PMU is a placeholder for an event source.

Returns

Event index in case of success, negative value otherwise.

🧚 static __rte_experimental __rte_always_inline uint64_t rte_pmu_read (unsigned int index) [static]

Warning — EXPERIMENTAL: this API may change without prior notice 😭

Read hardware counter configured to count occurrences of an event 📈

So here's the important caveat, listen up: this is called by an lcore (EAL thread) bound exclusively to a particular CPU, and it may not work as expected if it gets migrated elsewhere 😬 The reason being the event group is pinned, hence it's not supposed to be multiplexed with any other events. Also — and this is the iconic part — this is the only API which can be called concurrently by different lcores 💅✨

Parameters

  • index — Index of an event to be read.

Returns

Event value read from register. In case of errors or lack of support, 0 is returned. In other words, a stream of zeros in a trace file indicates a problem with reading that particular PMU event register 💀

Definition at line 204 of file rte_pmu.h.

🫶 Variable Documentation 🫶

🌟 struct rte_pmu rte_pmu [extern]

PMU state container. The holder of the state, the keeper of the vibes 💖

💌 Author 💌

Generated automatically by Doxygen for DPDK from the source code. (Not a person, just a robot doing its little robot thing 🤖✨)

And that's the whole page bestie, ily, go read your counters responsibly 🎀💅

Version 25.11.0 — dated Fri Jan 30 2026, signing off with a little rte_pmu_fini() of my own 😭🫶 mwah 💋

📦 where this page comes from