linux/samples/bpf/cpustat_user.c
Jakub Kicinski 2bf3e2ef42 samples: bpf: include bpf/bpf.h instead of local libbpf.h
There are two files in the tree called libbpf.h which is becoming
problematic.  Most samples don't actually need the local libbpf.h
they simply include it to get to bpf/bpf.h.  Include bpf/bpf.h
directly instead.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-14 22:52:10 -07:00

220 lines
4.7 KiB
C

// SPDX-License-Identifier: GPL-2.0
#define _GNU_SOURCE
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <signal.h>
#include <sched.h>
#include <string.h>
#include <unistd.h>
#include <fcntl.h>
#include <linux/bpf.h>
#include <locale.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <sys/resource.h>
#include <sys/wait.h>
#include <bpf/bpf.h>
#include "bpf_load.h"
#define MAX_CPU 8
#define MAX_PSTATE_ENTRIES 5
#define MAX_CSTATE_ENTRIES 3
#define MAX_STARS 40
#define CPUFREQ_MAX_SYSFS_PATH "/sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq"
#define CPUFREQ_LOWEST_FREQ "208000"
#define CPUFREQ_HIGHEST_FREQ "12000000"
struct cpu_stat_data {
unsigned long cstate[MAX_CSTATE_ENTRIES];
unsigned long pstate[MAX_PSTATE_ENTRIES];
};
static struct cpu_stat_data stat_data[MAX_CPU];
static void cpu_stat_print(void)
{
int i, j;
char state_str[sizeof("cstate-9")];
struct cpu_stat_data *data;
/* Clear screen */
printf("\033[2J");
/* Header */
printf("\nCPU states statistics:\n");
printf("%-10s ", "state(ms)");
for (i = 0; i < MAX_CSTATE_ENTRIES; i++) {
sprintf(state_str, "cstate-%d", i);
printf("%-11s ", state_str);
}
for (i = 0; i < MAX_PSTATE_ENTRIES; i++) {
sprintf(state_str, "pstate-%d", i);
printf("%-11s ", state_str);
}
printf("\n");
for (j = 0; j < MAX_CPU; j++) {
data = &stat_data[j];
printf("CPU-%-6d ", j);
for (i = 0; i < MAX_CSTATE_ENTRIES; i++)
printf("%-11ld ", data->cstate[i] / 1000000);
for (i = 0; i < MAX_PSTATE_ENTRIES; i++)
printf("%-11ld ", data->pstate[i] / 1000000);
printf("\n");
}
}
static void cpu_stat_update(int cstate_fd, int pstate_fd)
{
unsigned long key, value;
int c, i;
for (c = 0; c < MAX_CPU; c++) {
for (i = 0; i < MAX_CSTATE_ENTRIES; i++) {
key = c * MAX_CSTATE_ENTRIES + i;
bpf_map_lookup_elem(cstate_fd, &key, &value);
stat_data[c].cstate[i] = value;
}
for (i = 0; i < MAX_PSTATE_ENTRIES; i++) {
key = c * MAX_PSTATE_ENTRIES + i;
bpf_map_lookup_elem(pstate_fd, &key, &value);
stat_data[c].pstate[i] = value;
}
}
}
/*
* This function is copied from 'idlestat' tool function
* idlestat_wake_all() in idlestate.c.
*
* It sets the self running task affinity to cpus one by one so can wake up
* the specific CPU to handle scheduling; this results in all cpus can be
* waken up once and produce ftrace event 'trace_cpu_idle'.
*/
static int cpu_stat_inject_cpu_idle_event(void)
{
int rcpu, i, ret;
cpu_set_t cpumask;
cpu_set_t original_cpumask;
ret = sysconf(_SC_NPROCESSORS_CONF);
if (ret < 0)
return -1;
rcpu = sched_getcpu();
if (rcpu < 0)
return -1;
/* Keep track of the CPUs we will run on */
sched_getaffinity(0, sizeof(original_cpumask), &original_cpumask);
for (i = 0; i < ret; i++) {
/* Pointless to wake up ourself */
if (i == rcpu)
continue;
/* Pointless to wake CPUs we will not run on */
if (!CPU_ISSET(i, &original_cpumask))
continue;
CPU_ZERO(&cpumask);
CPU_SET(i, &cpumask);
sched_setaffinity(0, sizeof(cpumask), &cpumask);
}
/* Enable all the CPUs of the original mask */
sched_setaffinity(0, sizeof(original_cpumask), &original_cpumask);
return 0;
}
/*
* It's possible to have no any frequency change for long time and cannot
* get ftrace event 'trace_cpu_frequency' for long period, this introduces
* big deviation for pstate statistics.
*
* To solve this issue, below code forces to set 'scaling_max_freq' to 208MHz
* for triggering ftrace event 'trace_cpu_frequency' and then recovery back to
* the maximum frequency value 1.2GHz.
*/
static int cpu_stat_inject_cpu_frequency_event(void)
{
int len, fd;
fd = open(CPUFREQ_MAX_SYSFS_PATH, O_WRONLY);
if (fd < 0) {
printf("failed to open scaling_max_freq, errno=%d\n", errno);
return fd;
}
len = write(fd, CPUFREQ_LOWEST_FREQ, strlen(CPUFREQ_LOWEST_FREQ));
if (len < 0) {
printf("failed to open scaling_max_freq, errno=%d\n", errno);
goto err;
}
len = write(fd, CPUFREQ_HIGHEST_FREQ, strlen(CPUFREQ_HIGHEST_FREQ));
if (len < 0) {
printf("failed to open scaling_max_freq, errno=%d\n", errno);
goto err;
}
err:
close(fd);
return len;
}
static void int_exit(int sig)
{
cpu_stat_inject_cpu_idle_event();
cpu_stat_inject_cpu_frequency_event();
cpu_stat_update(map_fd[1], map_fd[2]);
cpu_stat_print();
exit(0);
}
int main(int argc, char **argv)
{
char filename[256];
int ret;
snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
if (load_bpf_file(filename)) {
printf("%s", bpf_log_buf);
return 1;
}
ret = cpu_stat_inject_cpu_idle_event();
if (ret < 0)
return 1;
ret = cpu_stat_inject_cpu_frequency_event();
if (ret < 0)
return 1;
signal(SIGINT, int_exit);
signal(SIGTERM, int_exit);
while (1) {
cpu_stat_update(map_fd[1], map_fd[2]);
cpu_stat_print();
sleep(5);
}
return 0;
}