diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 646a8279441..6bf9d40965e 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,8 @@
+2015-07-17  Yao Qi  <yao.qi@linaro.org>
+
+	* aarch64-linux-nat.c (aarch64_linux_get_debug_reg_capacity): Call
+	ptid_get_pid instead of get_thread_id.
+
 2015-07-17  Yao Qi  <yao.qi@linaro.org>
 
 	* remote.c (get_current_thread): Initialise ptid to null_ptid.
diff --git a/gdb/aarch64-linux-nat.c b/gdb/aarch64-linux-nat.c
index c4ddad5aea4..628ffe893d2 100644
--- a/gdb/aarch64-linux-nat.c
+++ b/gdb/aarch64-linux-nat.c
@@ -848,7 +848,7 @@ aarch64_linux_get_debug_reg_capacity (ptid_t ptid)
   struct iovec iov;
   struct user_hwdebug_state dreg_state;
 
-  tid = get_thread_id (ptid);
+  tid = ptid_get_pid (ptid);
   iov.iov_base = &dreg_state;
   iov.iov_len = sizeof (dreg_state);