1 /* Copyright (c) 2013-2015 PLUMgrid, http://plumgrid.com 2 * 3 * This program is free software; you can redistribute it and/or 4 * modify it under the terms of version 2 of the GNU General Public 5 * License as published by the Free Software Foundation. 6 */ 7 #include <stdio.h> 8 #include <stdlib.h> 9 #include <signal.h> 10 #include <unistd.h> 11 #include <stdbool.h> 12 #include <string.h> 13 #include <linux/bpf.h> 14 #include "libbpf.h" 15 #include "bpf_load.h" 16 17 #define ARRAY_SIZE(x) (sizeof(x) / sizeof(*(x))) 18 19 #define SLOTS 100 20 21 static void clear_stats(int fd) 22 { 23 __u32 key; 24 __u64 value = 0; 25 26 for (key = 0; key < SLOTS; key++) 27 bpf_update_elem(fd, &key, &value, BPF_ANY); 28 } 29 30 const char *color[] = { 31 "\033[48;5;255m", 32 "\033[48;5;252m", 33 "\033[48;5;250m", 34 "\033[48;5;248m", 35 "\033[48;5;246m", 36 "\033[48;5;244m", 37 "\033[48;5;242m", 38 "\033[48;5;240m", 39 "\033[48;5;238m", 40 "\033[48;5;236m", 41 "\033[48;5;234m", 42 "\033[48;5;232m", 43 }; 44 const int num_colors = ARRAY_SIZE(color); 45 46 const char nocolor[] = "\033[00m"; 47 48 const char *sym[] = { 49 " ", 50 " ", 51 ".", 52 ".", 53 "*", 54 "*", 55 "o", 56 "o", 57 "O", 58 "O", 59 "#", 60 "#", 61 }; 62 63 bool full_range = false; 64 bool text_only = false; 65 66 static void print_banner(void) 67 { 68 if (full_range) 69 printf("|1ns |10ns |100ns |1us |10us |100us" 70 " |1ms |10ms |100ms |1s |10s\n"); 71 else 72 printf("|1us |10us |100us |1ms |10ms " 73 "|100ms |1s |10s\n"); 74 } 75 76 static void print_hist(int fd) 77 { 78 __u32 key; 79 __u64 value; 80 __u64 cnt[SLOTS]; 81 __u64 max_cnt = 0; 82 __u64 total_events = 0; 83 84 for (key = 0; key < SLOTS; key++) { 85 value = 0; 86 bpf_lookup_elem(fd, &key, &value); 87 cnt[key] = value; 88 total_events += value; 89 if (value > max_cnt) 90 max_cnt = value; 91 } 92 clear_stats(fd); 93 for (key = full_range ? 0 : 29; key < SLOTS; key++) { 94 int c = num_colors * cnt[key] / (max_cnt + 1); 95 96 if (text_only) 97 printf("%s", sym[c]); 98 else 99 printf("%s %s", color[c], nocolor); 100 } 101 printf(" # %lld\n", total_events); 102 } 103 104 int main(int ac, char **argv) 105 { 106 char filename[256]; 107 int i; 108 109 snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]); 110 111 if (load_bpf_file(filename)) { 112 printf("%s", bpf_log_buf); 113 return 1; 114 } 115 116 for (i = 1; i < ac; i++) { 117 if (strcmp(argv[i], "-a") == 0) { 118 full_range = true; 119 } else if (strcmp(argv[i], "-t") == 0) { 120 text_only = true; 121 } else if (strcmp(argv[i], "-h") == 0) { 122 printf("Usage:\n" 123 " -a display wider latency range\n" 124 " -t text only\n"); 125 return 1; 126 } 127 } 128 129 printf(" heatmap of IO latency\n"); 130 if (text_only) 131 printf(" %s", sym[num_colors - 1]); 132 else 133 printf(" %s %s", color[num_colors - 1], nocolor); 134 printf(" - many events with this latency\n"); 135 136 if (text_only) 137 printf(" %s", sym[0]); 138 else 139 printf(" %s %s", color[0], nocolor); 140 printf(" - few events\n"); 141 142 for (i = 0; ; i++) { 143 if (i % 20 == 0) 144 print_banner(); 145 print_hist(map_fd[1]); 146 sleep(2); 147 } 148 149 return 0; 150 } 151