1 // SPDX-License-Identifier: GPL-2.0-only
2 /* Copyright (c) 2013-2015 PLUMgrid, http://plumgrid.com
10 #include <linux/bpf.h>
11 #include <sys/resource.h>
19 static void clear_stats(int fd)
21 unsigned int nr_cpus = bpf_num_possible_cpus();
22 __u64 values[nr_cpus];
25 memset(values, 0, sizeof(values));
26 for (key = 0; key < SLOTS; key++)
27 bpf_map_update_elem(fd, &key, values, BPF_ANY);
30 const char *color[] = {
44 const int num_colors = ARRAY_SIZE(color);
46 const char nocolor[] = "\033[00m";
63 bool full_range = false;
64 bool text_only = false;
66 static void print_banner(void)
69 printf("|1ns |10ns |100ns |1us |10us |100us"
70 " |1ms |10ms |100ms |1s |10s\n");
72 printf("|1us |10us |100us |1ms |10ms "
76 static void print_hist(int fd)
78 unsigned int nr_cpus = bpf_num_possible_cpus();
79 __u64 total_events = 0;
87 for (key = 0; key < SLOTS; key++) {
88 bpf_map_lookup_elem(fd, &key, values);
90 for (i = 0; i < nr_cpus; i++)
93 total_events += value;
98 for (key = full_range ? 0 : 29; key < SLOTS; key++) {
99 int c = num_colors * cnt[key] / (max_cnt + 1);
102 printf("%s", sym[c]);
104 printf("%s %s", color[c], nocolor);
106 printf(" # %lld\n", total_events);
109 int main(int ac, char **argv)
111 struct rlimit r = {1024*1024, RLIM_INFINITY};
115 snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
117 if (setrlimit(RLIMIT_MEMLOCK, &r)) {
118 perror("setrlimit(RLIMIT_MEMLOCK)");
122 if (load_bpf_file(filename)) {
123 printf("%s", bpf_log_buf);
127 for (i = 1; i < ac; i++) {
128 if (strcmp(argv[i], "-a") == 0) {
130 } else if (strcmp(argv[i], "-t") == 0) {
132 } else if (strcmp(argv[i], "-h") == 0) {
134 " -a display wider latency range\n"
140 printf(" heatmap of IO latency\n");
142 printf(" %s", sym[num_colors - 1]);
144 printf(" %s %s", color[num_colors - 1], nocolor);
145 printf(" - many events with this latency\n");
148 printf(" %s", sym[0]);
150 printf(" %s %s", color[0], nocolor);
151 printf(" - few events\n");
156 print_hist(map_fd[1]);