[PATCH v2 1/2] perf tools: Make find_vdso_map() more modular

Florian Fainelli
2018-10-25T17:55:48Z

In preparation for checking that the vectors page on the ARM
architecture, refactor the find_vdso_map() function to accept finding an
arbitrary string and create a dedicated helper function for that under
util/find-map.c and update find_vdso_map() to use it.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
---
tools/perf/util/find-map.c | 31 +++++++++++++++++++++++++++++++
tools/perf/util/find-vdso-map.c | 30 +++---------------------------
2 files changed, 34 insertions(+), 27 deletions(-)
create mode 100644 tools/perf/util/find-map.c

diff --git a/tools/perf/util/find-map.c b/tools/perf/util/find-map.c
new file mode 100644
index 000000000000..19a3431a7b2a
--- /dev/null
+++ b/tools/perf/util/find-map.c
@@ -0,0 +1,31 @@
+// SPDX-License-Identifier: GPL-2.0
+static int find_map(void **start, void **end, const char *name)
+{
+ 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], name, strlen(name)))
+ found = 1;
+ }
+
+ fclose(maps);
+ return !found;
+}
+
diff --git a/tools/perf/util/find-vdso-map.c b/tools/perf/util/find-vdso-map.c
index d7823e3508fc..840d7d6e29e2 100644
--- a/tools/perf/util/find-vdso-map.c
+++ b/tools/perf/util/find-vdso-map.c
@@ -1,31 +1,7 @@
// SPDX-License-Identifier: GPL-2.0
+#include "find-map.c"
+
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;
+ return find_map(start, end, VDSO__MAP_NAME);
}
--
2.17.1