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-rw-r--r--samples/bpf/tracex2_user.c186
1 files changed, 186 insertions, 0 deletions
diff --git a/samples/bpf/tracex2_user.c b/samples/bpf/tracex2_user.c
new file mode 100644
index 000000000..dd6205c6b
--- /dev/null
+++ b/samples/bpf/tracex2_user.c
@@ -0,0 +1,186 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <stdio.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <signal.h>
+#include <string.h>
+
+#include <bpf/bpf.h>
+#include <bpf/libbpf.h>
+#include "bpf_util.h"
+
+#define MAX_INDEX 64
+#define MAX_STARS 38
+
+/* my_map, my_hist_map */
+static int map_fd[2];
+
+static void stars(char *str, long val, long max, int width)
+{
+ int i;
+
+ for (i = 0; i < (width * val / max) - 1 && i < width - 1; i++)
+ str[i] = '*';
+ if (val > max)
+ str[i - 1] = '+';
+ str[i] = '\0';
+}
+
+struct task {
+ char comm[16];
+ __u64 pid_tgid;
+ __u64 uid_gid;
+};
+
+struct hist_key {
+ struct task t;
+ __u32 index;
+};
+
+#define SIZE sizeof(struct task)
+
+static void print_hist_for_pid(int fd, void *task)
+{
+ unsigned int nr_cpus = bpf_num_possible_cpus();
+ struct hist_key key = {}, next_key;
+ long values[nr_cpus];
+ char starstr[MAX_STARS];
+ long value;
+ long data[MAX_INDEX] = {};
+ int max_ind = -1;
+ long max_value = 0;
+ int i, ind;
+
+ while (bpf_map_get_next_key(fd, &key, &next_key) == 0) {
+ if (memcmp(&next_key, task, SIZE)) {
+ key = next_key;
+ continue;
+ }
+ bpf_map_lookup_elem(fd, &next_key, values);
+ value = 0;
+ for (i = 0; i < nr_cpus; i++)
+ value += values[i];
+ ind = next_key.index;
+ data[ind] = value;
+ if (value && ind > max_ind)
+ max_ind = ind;
+ if (value > max_value)
+ max_value = value;
+ key = next_key;
+ }
+
+ printf(" syscall write() stats\n");
+ printf(" byte_size : count distribution\n");
+ for (i = 1; i <= max_ind + 1; i++) {
+ stars(starstr, data[i - 1], max_value, MAX_STARS);
+ printf("%8ld -> %-8ld : %-8ld |%-*s|\n",
+ (1l << i) >> 1, (1l << i) - 1, data[i - 1],
+ MAX_STARS, starstr);
+ }
+}
+
+static void print_hist(int fd)
+{
+ struct hist_key key = {}, next_key;
+ static struct task tasks[1024];
+ int task_cnt = 0;
+ int i;
+
+ while (bpf_map_get_next_key(fd, &key, &next_key) == 0) {
+ int found = 0;
+
+ for (i = 0; i < task_cnt; i++)
+ if (memcmp(&tasks[i], &next_key, SIZE) == 0)
+ found = 1;
+ if (!found)
+ memcpy(&tasks[task_cnt++], &next_key, SIZE);
+ key = next_key;
+ }
+
+ for (i = 0; i < task_cnt; i++) {
+ printf("\npid %d cmd %s uid %d\n",
+ (__u32) tasks[i].pid_tgid,
+ tasks[i].comm,
+ (__u32) tasks[i].uid_gid);
+ print_hist_for_pid(fd, &tasks[i]);
+ }
+
+}
+
+static void int_exit(int sig)
+{
+ print_hist(map_fd[1]);
+ exit(0);
+}
+
+int main(int ac, char **argv)
+{
+ long key, next_key, value;
+ struct bpf_link *links[2];
+ struct bpf_program *prog;
+ struct bpf_object *obj;
+ char filename[256];
+ int i, j = 0;
+ FILE *f;
+
+ snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
+ obj = bpf_object__open_file(filename, NULL);
+ if (libbpf_get_error(obj)) {
+ fprintf(stderr, "ERROR: opening BPF object file failed\n");
+ return 0;
+ }
+
+ /* load BPF program */
+ if (bpf_object__load(obj)) {
+ fprintf(stderr, "ERROR: loading BPF object file failed\n");
+ goto cleanup;
+ }
+
+ map_fd[0] = bpf_object__find_map_fd_by_name(obj, "my_map");
+ map_fd[1] = bpf_object__find_map_fd_by_name(obj, "my_hist_map");
+ if (map_fd[0] < 0 || map_fd[1] < 0) {
+ fprintf(stderr, "ERROR: finding a map in obj file failed\n");
+ goto cleanup;
+ }
+
+ signal(SIGINT, int_exit);
+ signal(SIGTERM, int_exit);
+
+ /* start 'ping' in the background to have some kfree_skb events */
+ f = popen("ping -4 -c5 localhost", "r");
+ (void) f;
+
+ /* start 'dd' in the background to have plenty of 'write' syscalls */
+ f = popen("dd if=/dev/zero of=/dev/null count=5000000", "r");
+ (void) f;
+
+ bpf_object__for_each_program(prog, obj) {
+ links[j] = bpf_program__attach(prog);
+ if (libbpf_get_error(links[j])) {
+ fprintf(stderr, "ERROR: bpf_program__attach failed\n");
+ links[j] = NULL;
+ goto cleanup;
+ }
+ j++;
+ }
+
+ for (i = 0; i < 5; i++) {
+ key = 0;
+ while (bpf_map_get_next_key(map_fd[0], &key, &next_key) == 0) {
+ bpf_map_lookup_elem(map_fd[0], &next_key, &value);
+ printf("location 0x%lx count %ld\n", next_key, value);
+ key = next_key;
+ }
+ if (key)
+ printf("\n");
+ sleep(1);
+ }
+ print_hist(map_fd[1]);
+
+cleanup:
+ for (j--; j >= 0; j--)
+ bpf_link__destroy(links[j]);
+
+ bpf_object__close(obj);
+ return 0;
+}