1 // SPDX-License-Identifier: GPL-2.0-only 2 /* Copyright (c) 2013-2015 PLUMgrid, http://plumgrid.com 3 */ 4 #include <stdio.h> 5 #include <stdlib.h> 6 #include <signal.h> 7 #include <unistd.h> 8 #include <stdbool.h> 9 #include <string.h> 10 #include <linux/bpf.h> 11 #include <sys/resource.h> 12 13 #include <bpf/bpf.h> 14 #include "bpf_load.h" 15 #include "bpf_util.h" 16 17 #define SLOTS 100 18 19 static void clear_stats(int fd) 20 { 21 unsigned int nr_cpus = bpf_num_possible_cpus(); 22 __u64 values[nr_cpus]; 23 __u32 key; 24 25 memset(values, 0, sizeof(values)); 26 for (key = 0; key < SLOTS; key++) 27 bpf_map_update_elem(fd, &key, values, 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 unsigned int nr_cpus = bpf_num_possible_cpus(); 79 __u64 total_events = 0; 80 long values[nr_cpus]; 81 __u64 max_cnt = 0; 82 __u64 cnt[SLOTS]; 83 __u64 value; 84 __u32 key; 85 int i; 86 87 for (key = 0; key < SLOTS; key++) { 88 bpf_map_lookup_elem(fd, &key, values); 89 value = 0; 90 for (i = 0; i < nr_cpus; i++) 91 value += values[i]; 92 cnt[key] = value; 93 total_events += value; 94 if (value > max_cnt) 95 max_cnt = value; 96 } 97 clear_stats(fd); 98 for (key = full_range ? 0 : 29; key < SLOTS; key++) { 99 int c = num_colors * cnt[key] / (max_cnt + 1); 100 101 if (text_only) 102 printf("%s", sym[c]); 103 else 104 printf("%s %s", color[c], nocolor); 105 } 106 printf(" # %lld\n", total_events); 107 } 108 109 int main(int ac, char **argv) 110 { 111 struct rlimit r = {1024*1024, RLIM_INFINITY}; 112 char filename[256]; 113 int i; 114 115 snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]); 116 117 if (setrlimit(RLIMIT_MEMLOCK, &r)) { 118 perror("setrlimit(RLIMIT_MEMLOCK)"); 119 return 1; 120 } 121 122 if (load_bpf_file(filename)) { 123 printf("%s", bpf_log_buf); 124 return 1; 125 } 126 127 for (i = 1; i < ac; i++) { 128 if (strcmp(argv[i], "-a") == 0) { 129 full_range = true; 130 } else if (strcmp(argv[i], "-t") == 0) { 131 text_only = true; 132 } else if (strcmp(argv[i], "-h") == 0) { 133 printf("Usage:\n" 134 " -a display wider latency range\n" 135 " -t text only\n"); 136 return 1; 137 } 138 } 139 140 printf(" heatmap of IO latency\n"); 141 if (text_only) 142 printf(" %s", sym[num_colors - 1]); 143 else 144 printf(" %s %s", color[num_colors - 1], nocolor); 145 printf(" - many events with this latency\n"); 146 147 if (text_only) 148 printf(" %s", sym[0]); 149 else 150 printf(" %s %s", color[0], nocolor); 151 printf(" - few events\n"); 152 153 for (i = 0; ; i++) { 154 if (i % 20 == 0) 155 print_banner(); 156 print_hist(map_fd[1]); 157 sleep(2); 158 } 159 160 return 0; 161 } 162