diff options
Diffstat (limited to 'samples/bpf/lwt_len_hist_user.c')
-rw-r--r-- | samples/bpf/lwt_len_hist_user.c | 77 |
1 files changed, 77 insertions, 0 deletions
diff --git a/samples/bpf/lwt_len_hist_user.c b/samples/bpf/lwt_len_hist_user.c new file mode 100644 index 0000000000..430a4b7e35 --- /dev/null +++ b/samples/bpf/lwt_len_hist_user.c @@ -0,0 +1,77 @@ +// SPDX-License-Identifier: GPL-2.0 +#include <linux/unistd.h> +#include <linux/bpf.h> + +#include <stdlib.h> +#include <stdio.h> +#include <unistd.h> +#include <string.h> +#include <errno.h> +#include <arpa/inet.h> + +#include <bpf/bpf.h> +#include "bpf_util.h" + +#define MAX_INDEX 64 +#define MAX_STARS 38 + +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'; +} + +int main(int argc, char **argv) +{ + unsigned int nr_cpus = bpf_num_possible_cpus(); + const char *map_filename = "/sys/fs/bpf/tc/globals/lwt_len_hist_map"; + uint64_t values[nr_cpus], sum, max_value = 0, data[MAX_INDEX] = {}; + uint64_t key = 0, next_key, max_key = 0; + char starstr[MAX_STARS]; + int i, map_fd; + + map_fd = bpf_obj_get(map_filename); + if (map_fd < 0) { + fprintf(stderr, "bpf_obj_get(%s): %s(%d)\n", + map_filename, strerror(errno), errno); + return -1; + } + + while (bpf_map_get_next_key(map_fd, &key, &next_key) == 0) { + if (next_key >= MAX_INDEX) { + fprintf(stderr, "Key %lu out of bounds\n", next_key); + continue; + } + + bpf_map_lookup_elem(map_fd, &next_key, values); + + sum = 0; + for (i = 0; i < nr_cpus; i++) + sum += values[i]; + + data[next_key] = sum; + if (sum && next_key > max_key) + max_key = next_key; + + if (sum > max_value) + max_value = sum; + + key = next_key; + } + + for (i = 1; i <= max_key + 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); + } + + close(map_fd); + + return 0; +} |