7 #include <sys/resource.h>
16 static void stars(char *str, long val, long max, int width)
20 for (i = 0; i < (width * val / max) - 1 && i < width - 1; i++)
38 #define SIZE sizeof(struct task)
40 static void print_hist_for_pid(int fd, void *task)
42 unsigned int nr_cpus = bpf_num_possible_cpus();
43 struct hist_key key = {}, next_key;
45 char starstr[MAX_STARS];
47 long data[MAX_INDEX] = {};
52 while (bpf_map_get_next_key(fd, &key, &next_key) == 0) {
53 if (memcmp(&next_key, task, SIZE)) {
57 bpf_map_lookup_elem(fd, &next_key, values);
59 for (i = 0; i < nr_cpus; i++)
63 if (value && ind > max_ind)
65 if (value > max_value)
70 printf(" syscall write() stats\n");
71 printf(" byte_size : count distribution\n");
72 for (i = 1; i <= max_ind + 1; i++) {
73 stars(starstr, data[i - 1], max_value, MAX_STARS);
74 printf("%8ld -> %-8ld : %-8ld |%-*s|\n",
75 (1l << i) >> 1, (1l << i) - 1, data[i - 1],
80 static void print_hist(int fd)
82 struct hist_key key = {}, next_key;
83 static struct task tasks[1024];
87 while (bpf_map_get_next_key(fd, &key, &next_key) == 0) {
90 for (i = 0; i < task_cnt; i++)
91 if (memcmp(&tasks[i], &next_key, SIZE) == 0)
94 memcpy(&tasks[task_cnt++], &next_key, SIZE);
98 for (i = 0; i < task_cnt; i++) {
99 printf("\npid %d cmd %s uid %d\n",
100 (__u32) tasks[i].pid_tgid,
102 (__u32) tasks[i].uid_gid);
103 print_hist_for_pid(fd, &tasks[i]);
108 static void int_exit(int sig)
110 print_hist(map_fd[1]);
114 int main(int ac, char **argv)
116 struct rlimit r = {1024*1024, RLIM_INFINITY};
118 long key, next_key, value;
122 snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
124 if (setrlimit(RLIMIT_MEMLOCK, &r)) {
125 perror("setrlimit(RLIMIT_MEMLOCK)");
129 signal(SIGINT, int_exit);
131 /* start 'ping' in the background to have some kfree_skb events */
132 f = popen("ping -c5 localhost", "r");
135 /* start 'dd' in the background to have plenty of 'write' syscalls */
136 f = popen("dd if=/dev/zero of=/dev/null count=5000000", "r");
139 if (load_bpf_file(filename)) {
140 printf("%s", bpf_log_buf);
144 for (i = 0; i < 5; i++) {
146 while (bpf_map_get_next_key(map_fd[0], &key, &next_key) == 0) {
147 bpf_map_lookup_elem(map_fd[0], &next_key, &value);
148 printf("location 0x%lx count %ld\n", next_key, value);
155 print_hist(map_fd[1]);