Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / samples / bpf / tracex3_user.c

diff --git a/kernel/samples/bpf/tracex3_user.c b/kernel/samples/bpf/tracex3_user.c
new file mode 100644 (file)
index 0000000..0aaa933
--- /dev/null
+++ b/kernel/samples/bpf/tracex3_user.c
@@ -0,0 +1,150 @@
+/* Copyright (c) 2013-2015 PLUMgrid, http://plumgrid.com
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ */
+#include <stdio.h>
+#include <stdlib.h>
+#include <signal.h>
+#include <unistd.h>
+#include <stdbool.h>
+#include <string.h>
+#include <linux/bpf.h>
+#include "libbpf.h"
+#include "bpf_load.h"
+
+#define ARRAY_SIZE(x) (sizeof(x) / sizeof(*(x)))
+
+#define SLOTS 100
+
+static void clear_stats(int fd)
+{
+       __u32 key;
+       __u64 value = 0;
+
+       for (key = 0; key < SLOTS; key++)
+               bpf_update_elem(fd, &key, &value, 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)
+{
+       __u32 key;
+       __u64 value;
+       __u64 cnt[SLOTS];
+       __u64 max_cnt = 0;
+       __u64 total_events = 0;
+
+       for (key = 0; key < SLOTS; key++) {
+               value = 0;
+               bpf_lookup_elem(fd, &key, &value);
+               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)
+{
+       char filename[256];
+       int i;
+
+       snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
+
+       if (load_bpf_file(filename)) {
+               printf("%s", bpf_log_buf);
+               return 1;
+       }
+
+       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;
+               }
+       }
+
+       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[1]);
+               sleep(2);
+       }
+
+       return 0;
+}