tools/testing/selftests/powerpc/pmu/event.c

Source file repositories/reference/linux-study-clean/tools/testing/selftests/powerpc/pmu/event.c

File Facts

System
Linux kernel
Corpus path
tools/testing/selftests/powerpc/pmu/event.c
Extension
.c
Size
3223 bytes
Lines
149
Domain
Support Tooling And Documentation
Bucket
tools
Inferred role
Support Tooling And Documentation: implementation source
Status
source implementation candidate

Why This File Exists

Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.

Dependency Surface

Detected Declarations

Annotated Snippet

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright 2013, Michael Ellerman, IBM Corp.
 */

#define _GNU_SOURCE
#include <unistd.h>
#include <sys/syscall.h>
#include <string.h>
#include <stdio.h>
#include <stdbool.h>
#include <sys/ioctl.h>

#include "event.h"


int perf_event_open(struct perf_event_attr *attr, pid_t pid, int cpu,
		int group_fd, unsigned long flags)
{
	return syscall(__NR_perf_event_open, attr, pid, cpu,
			   group_fd, flags);
}

static void  __event_init_opts(struct event *e, u64 config,
			       int type, char *name, bool sampling)
{
	memset(e, 0, sizeof(*e));

	e->name = name;

	e->attr.type = type;
	e->attr.config = config;
	e->attr.size = sizeof(e->attr);
	/* This has to match the structure layout in the header */
	e->attr.read_format = PERF_FORMAT_TOTAL_TIME_ENABLED | \
				  PERF_FORMAT_TOTAL_TIME_RUNNING;
	if (sampling) {
		e->attr.sample_period = 1000;
		e->attr.sample_type = PERF_SAMPLE_REGS_INTR;
		e->attr.disabled = 1;
	}
}

void event_init_opts(struct event *e, u64 config, int type, char *name)
{
	__event_init_opts(e, config, type, name, false);
}

void event_init_named(struct event *e, u64 config, char *name)
{
	event_init_opts(e, config, PERF_TYPE_RAW, name);
}

void event_init(struct event *e, u64 config)
{
	event_init_opts(e, config, PERF_TYPE_RAW, "event");
}

void event_init_sampling(struct event *e, u64 config)
{
	__event_init_opts(e, config, PERF_TYPE_RAW, "event", true);
}

#define PERF_CURRENT_PID	0
#define PERF_NO_PID		-1
#define PERF_NO_CPU		-1
#define PERF_NO_GROUP		-1

int event_open_with_options(struct event *e, pid_t pid, int cpu, int group_fd)
{
	e->fd = perf_event_open(&e->attr, pid, cpu, group_fd, 0);
	if (e->fd == -1) {
		perror("perf_event_open");
		return -1;
	}

	return 0;
}

int event_open_with_group(struct event *e, int group_fd)
{
	return event_open_with_options(e, PERF_CURRENT_PID, PERF_NO_CPU, group_fd);
}

int event_open_with_pid(struct event *e, pid_t pid)
{
	return event_open_with_options(e, pid, PERF_NO_CPU, PERF_NO_GROUP);
}

int event_open_with_cpu(struct event *e, int cpu)

Annotation

Implementation Notes