1 files changed, 17 insertions, 0 deletions

diff --git a/tools/perf/util/util.c b/tools/perf/util/util.c
index 214265674ddd..5b3ea49aa63e 100644
--- a/tools/perf/util/util.c
+++ b/tools/perf/util/util.c
@@ -114,3 +114,20 @@ unsigned long convert_unit(unsigned long value, char *unit)
 
         return value;
 }
+
+int readn(int fd, void *buf, size_t n)
+{
+        void *buf_start = buf;
+
+        while (n) {
+                int ret = read(fd, buf, n);
+
+                if (ret <= 0)
+                        return ret;
+
+                n -= ret;
+                buf += ret;
+        }
+
+        return buf - buf_start;
+}