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-rw-r--r--samples/bpf/tracex3_user.c183
1 files changed, 183 insertions, 0 deletions
diff --git a/samples/bpf/tracex3_user.c b/samples/bpf/tracex3_user.c
new file mode 100644
index 000000000..d5eebace3
--- /dev/null
+++ b/samples/bpf/tracex3_user.c
@@ -0,0 +1,183 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright (c) 2013-2015 PLUMgrid, http://plumgrid.com
+ */
+#include <stdio.h>
+#include <stdlib.h>
+#include <signal.h>
+#include <unistd.h>
+#include <stdbool.h>
+#include <string.h>
+
+#include <bpf/bpf.h>
+#include <bpf/libbpf.h>
+#include "bpf_util.h"
+
+#define SLOTS 100
+
+static void clear_stats(int fd)
+{
+ unsigned int nr_cpus = bpf_num_possible_cpus();
+ __u64 values[nr_cpus];
+ __u32 key;
+
+ memset(values, 0, sizeof(values));
+ for (key = 0; key < SLOTS; key++)
+ bpf_map_update_elem(fd, &key, values, BPF_ANY);
+}
+
+const char *color[] = {
+ "\033[48;5;255m",
+ "\033[48;5;252m",
+ "\033[48;5;250m",
+ "\033[48;5;248m",
+ "\033[48;5;246m",
+ "\033[48;5;244m",
+ "\033[48;5;242m",
+ "\033[48;5;240m",
+ "\033[48;5;238m",
+ "\033[48;5;236m",
+ "\033[48;5;234m",
+ "\033[48;5;232m",
+};
+const int num_colors = ARRAY_SIZE(color);
+
+const char nocolor[] = "\033[00m";
+
+const char *sym[] = {
+ " ",
+ " ",
+ ".",
+ ".",
+ "*",
+ "*",
+ "o",
+ "o",
+ "O",
+ "O",
+ "#",
+ "#",
+};
+
+bool full_range = false;
+bool text_only = false;
+
+static void print_banner(void)
+{
+ if (full_range)
+ printf("|1ns |10ns |100ns |1us |10us |100us"
+ " |1ms |10ms |100ms |1s |10s\n");
+ else
+ printf("|1us |10us |100us |1ms |10ms "
+ "|100ms |1s |10s\n");
+}
+
+static void print_hist(int fd)
+{
+ unsigned int nr_cpus = bpf_num_possible_cpus();
+ __u64 total_events = 0;
+ long values[nr_cpus];
+ __u64 max_cnt = 0;
+ __u64 cnt[SLOTS];
+ __u64 value;
+ __u32 key;
+ int i;
+
+ for (key = 0; key < SLOTS; key++) {
+ bpf_map_lookup_elem(fd, &key, values);
+ value = 0;
+ for (i = 0; i < nr_cpus; i++)
+ value += values[i];
+ cnt[key] = value;
+ total_events += value;
+ if (value > max_cnt)
+ max_cnt = value;
+ }
+ clear_stats(fd);
+ for (key = full_range ? 0 : 29; key < SLOTS; key++) {
+ int c = num_colors * cnt[key] / (max_cnt + 1);
+
+ if (text_only)
+ printf("%s", sym[c]);
+ else
+ printf("%s %s", color[c], nocolor);
+ }
+ printf(" # %lld\n", total_events);
+}
+
+int main(int ac, char **argv)
+{
+ struct bpf_link *links[2];
+ struct bpf_program *prog;
+ struct bpf_object *obj;
+ char filename[256];
+ int map_fd, i, j = 0;
+
+ for (i = 1; i < ac; i++) {
+ if (strcmp(argv[i], "-a") == 0) {
+ full_range = true;
+ } else if (strcmp(argv[i], "-t") == 0) {
+ text_only = true;
+ } else if (strcmp(argv[i], "-h") == 0) {
+ printf("Usage:\n"
+ " -a display wider latency range\n"
+ " -t text only\n");
+ return 1;
+ }
+ }
+
+ 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 = bpf_object__find_map_fd_by_name(obj, "lat_map");
+ if (map_fd < 0) {
+ fprintf(stderr, "ERROR: finding a map in obj file failed\n");
+ goto cleanup;
+ }
+
+ 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++;
+ }
+
+ printf(" heatmap of IO latency\n");
+ if (text_only)
+ printf(" %s", sym[num_colors - 1]);
+ else
+ printf(" %s %s", color[num_colors - 1], nocolor);
+ printf(" - many events with this latency\n");
+
+ if (text_only)
+ printf(" %s", sym[0]);
+ else
+ printf(" %s %s", color[0], nocolor);
+ printf(" - few events\n");
+
+ for (i = 0; ; i++) {
+ if (i % 20 == 0)
+ print_banner();
+ print_hist(map_fd);
+ sleep(2);
+ }
+
+cleanup:
+ for (j--; j >= 0; j--)
+ bpf_link__destroy(links[j]);
+
+ bpf_object__close(obj);
+ return 0;
+}