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/* Copyright (c) 2013-2015 PLUMgrid, http://plumgrid.com
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of version 2 of the GNU General Public
* License as published by the Free Software Foundation.
*/
#include <stdio.h>
#include <stdlib.h>
#include <signal.h>
#include <unistd.h>
#include <stdbool.h>
#include <string.h>
#include <linux/bpf.h>
#include "libbpf.h"
#include "bpf_load.h"
#include "bpf_util.h"
#define ARRAY_SIZE(x) (sizeof(x) / sizeof(*(x)))
#define SLOTS 100
static void clear_stats(int fd)
{
unsigned int nr_cpus = bpf_num_possible_cpus();
__u64 values[nr_cpus];
__u32 key;
memset(values, 0, sizeof(values));
for (key = 0; key < SLOTS; key++)
bpf_update_elem(fd, &key, values, BPF_ANY);
}
const char *color[] = {
"\033[48;5;255m",
"\033[48;5;252m",
"\033[48;5;250m",
"\033[48;5;248m",
"\033[48;5;246m",
"\033[48;5;244m",
"\033[48;5;242m",
"\033[48;5;240m",
"\033[48;5;238m",
"\033[48;5;236m",
"\033[48;5;234m",
"\033[48;5;232m",
};
const int num_colors = ARRAY_SIZE(color);
const char nocolor[] = "\033[00m";
const char *sym[] = {
" ",
" ",
".",
".",
"*",
"*",
"o",
"o",
"O",
"O",
"#",
"#",
};
bool full_range = false;
bool text_only = false;
static void print_banner(void)
{
if (full_range)
printf("|1ns |10ns |100ns |1us |10us |100us"
" |1ms |10ms |100ms |1s |10s\n");
else
printf("|1us |10us |100us |1ms |10ms "
"|100ms |1s |10s\n");
}
static void print_hist(int fd)
{
unsigned int nr_cpus = bpf_num_possible_cpus();
__u64 total_events = 0;
long values[nr_cpus];
__u64 max_cnt = 0;
__u64 cnt[SLOTS];
__u64 value;
__u32 key;
int i;
for (key = 0; key < SLOTS; key++) {
bpf_lookup_elem(fd, &key, values);
value = 0;
for (i = 0; i < nr_cpus; i++)
value += values[i];
cnt[key] = value;
total_events += value;
if (value > max_cnt)
max_cnt = value;
}
clear_stats(fd);
for (key = full_range ? 0 : 29; key < SLOTS; key++) {
int c = num_colors * cnt[key] / (max_cnt + 1);
if (text_only)
printf("%s", sym[c]);
else
printf("%s %s", color[c], nocolor);
}
printf(" # %lld\n", total_events);
}
int main(int ac, char **argv)
{
char filename[256];
int i;
snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
if (load_bpf_file(filename)) {
printf("%s", bpf_log_buf);
return 1;
}
for (i = 1; i < ac; i++) {
if (strcmp(argv[i], "-a") == 0) {
full_range = true;
} else if (strcmp(argv[i], "-t") == 0) {
text_only = true;
} else if (strcmp(argv[i], "-h") == 0) {
printf("Usage:\n"
" -a display wider latency range\n"
" -t text only\n");
return 1;
}
}
printf(" heatmap of IO latency\n");
if (text_only)
printf(" %s", sym[num_colors - 1]);
else
printf(" %s %s", color[num_colors - 1], nocolor);
printf(" - many events with this latency\n");
if (text_only)
printf(" %s", sym[0]);
else
printf(" %s %s", color[0], nocolor);
printf(" - few events\n");
for (i = 0; ; i++) {
if (i % 20 == 0)
print_banner();
print_hist(map_fd[1]);
sleep(2);
}
return 0;
}
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