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 <sys/resource.h> 15 16 #include <bpf/bpf.h> 17 #include "bpf_load.h" 18 #include "bpf_util.h" 19 20 #define SLOTS 100 21 22 static void clear_stats(int fd) 23 { 24 unsigned int nr_cpus = bpf_num_possible_cpus(); 25 __u64 values[nr_cpus]; 26 __u32 key; 27 28 memset(values, 0, sizeof(values)); 29 for (key = 0; key < SLOTS; key++) 30 bpf_map_update_elem(fd, &key, values, BPF_ANY); 31 } 32 33 const char *color[] = { 34 "\033[48;5;255m", 35 "\033[48;5;252m", 36 "\033[48;5;250m", 37 "\033[48;5;248m", 38 "\033[48;5;246m", 39 "\033[48;5;244m", 40 "\033[48;5;242m", 41 "\033[48;5;240m", 42 "\033[48;5;238m", 43 "\033[48;5;236m", 44 "\033[48;5;234m", 45 "\033[48;5;232m", 46 }; 47 const int num_colors = ARRAY_SIZE(color); 48 49 const char nocolor[] = "\033[00m"; 50 51 const char *sym[] = { 52 " ", 53 " ", 54 ".", 55 ".", 56 "*", 57 "*", 58 "o", 59 "o", 60 "O", 61 "O", 62 "#", 63 "#", 64 }; 65 66 bool full_range = false; 67 bool text_only = false; 68 69 static void print_banner(void) 70 { 71 if (full_range) 72 printf("|1ns |10ns |100ns |1us |10us |100us" 73 " |1ms |10ms |100ms |1s |10s\n"); 74 else 75 printf("|1us |10us |100us |1ms |10ms " 76 "|100ms |1s |10s\n"); 77 } 78 79 static void print_hist(int fd) 80 { 81 unsigned int nr_cpus = bpf_num_possible_cpus(); 82 __u64 total_events = 0; 83 long values[nr_cpus]; 84 __u64 max_cnt = 0; 85 __u64 cnt[SLOTS]; 86 __u64 value; 87 __u32 key; 88 int i; 89 90 for (key = 0; key < SLOTS; key++) { 91 bpf_map_lookup_elem(fd, &key, values); 92 value = 0; 93 for (i = 0; i < nr_cpus; i++) 94 value += values[i]; 95 cnt[key] = value; 96 total_events += value; 97 if (value > max_cnt) 98 max_cnt = value; 99 } 100 clear_stats(fd); 101 for (key = full_range ? 0 : 29; key < SLOTS; key++) { 102 int c = num_colors * cnt[key] / (max_cnt + 1); 103 104 if (text_only) 105 printf("%s", sym[c]); 106 else 107 printf("%s %s", color[c], nocolor); 108 } 109 printf(" # %lld\n", total_events); 110 } 111 112 int main(int ac, char **argv) 113 { 114 struct rlimit r = {1024*1024, RLIM_INFINITY}; 115 char filename[256]; 116 int i; 117 118 snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]); 119 120 if (setrlimit(RLIMIT_MEMLOCK, &r)) { 121 perror("setrlimit(RLIMIT_MEMLOCK)"); 122 return 1; 123 } 124 125 if (load_bpf_file(filename)) { 126 printf("%s", bpf_log_buf); 127 return 1; 128 } 129 130 for (i = 1; i < ac; i++) { 131 if (strcmp(argv[i], "-a") == 0) { 132 full_range = true; 133 } else if (strcmp(argv[i], "-t") == 0) { 134 text_only = true; 135 } else if (strcmp(argv[i], "-h") == 0) { 136 printf("Usage:\n" 137 " -a display wider latency range\n" 138 " -t text only\n"); 139 return 1; 140 } 141 } 142 143 printf(" heatmap of IO latency\n"); 144 if (text_only) 145 printf(" %s", sym[num_colors - 1]); 146 else 147 printf(" %s %s", color[num_colors - 1], nocolor); 148 printf(" - many events with this latency\n"); 149 150 if (text_only) 151 printf(" %s", sym[0]); 152 else 153 printf(" %s %s", color[0], nocolor); 154 printf(" - few events\n"); 155 156 for (i = 0; ; i++) { 157 if (i % 20 == 0) 158 print_banner(); 159 print_hist(map_fd[1]); 160 sleep(2); 161 } 162 163 return 0; 164 } 165