Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / tools / perf / util / find-vdso-map.c

diff --git a/kernel/tools/perf/util/find-vdso-map.c b/kernel/tools/perf/util/find-vdso-map.c
new file mode 100644 (file)
index 0000000..95ef1cf
--- /dev/null
+++ b/kernel/tools/perf/util/find-vdso-map.c
@@ -0,0 +1,30 @@
+static int find_vdso_map(void **start, void **end)
+{
+       FILE *maps;
+       char line[128];
+       int found = 0;
+
+       maps = fopen("/proc/self/maps", "r");
+       if (!maps) {
+               fprintf(stderr, "vdso: cannot open maps\n");
+               return -1;
+       }
+
+       while (!found && fgets(line, sizeof(line), maps)) {
+               int m = -1;
+
+               /* We care only about private r-x mappings. */
+               if (2 != sscanf(line, "%p-%p r-xp %*x %*x:%*x %*u %n",
+                               start, end, &m))
+                       continue;
+               if (m < 0)
+                       continue;
+
+               if (!strncmp(&line[m], VDSO__MAP_NAME,
+                            sizeof(VDSO__MAP_NAME) - 1))
+                       found = 1;
+       }
+
+       fclose(maps);
+       return !found;
+}