--- a/remote.c
+++ b/remote.c
@@ -215,6 +215,8 @@ static int remote_get_trace_status (stru
 static int remote_upload_tracepoints (struct uploaded_tp **utpp);
 
 static int remote_upload_trace_state_variables (struct uploaded_tsv **utsvp);
+
+static void remote_upload_trace_default_collect (char **collectp);
   
 static void remote_query_supported (void);
 
@@ -1286,6 +1288,8 @@ enum {
   PACKET_Qbtrace_off,
   PACKET_Qbtrace_bts,
   PACKET_qXfer_btrace,
+  PACKET_QTDDCsrc,
+  PACKET_qTDC,
   PACKET_MAX
 };
 
@@ -3567,6 +3571,7 @@ remote_start_remote (int from_tty, struc
     {
       struct uploaded_tp *uploaded_tps = NULL;
       struct uploaded_tsv *uploaded_tsvs = NULL;
+      char *uploaded_default_collect = NULL;
 
       if (current_trace_status ()->running)
 	printf_filtered (_("Trace is already running on the target.\n"));
@@ -3581,6 +3586,10 @@ remote_start_remote (int from_tty, struc
       remote_upload_tracepoints (&uploaded_tps);
 
       merge_uploaded_tracepoints (&uploaded_tps);
+
+      remote_upload_trace_default_collect (&uploaded_default_collect);
+
+      trace_set_default_collect (uploaded_default_collect);
     }
 
   /* The thread and inferior lists are now synchronized with the
@@ -10567,6 +10576,33 @@ remote_download_tracepoint (struct bp_lo
   do_cleanups (old_chain);
 }
 
+/* Download COLLECT that is default collect string to target.  */
+
+static void
+remote_download_tracepoint_default_collect (char *collect)
+{
+  char buf[BUF_SIZE];
+  struct remote_state *rs = get_remote_state ();
+  enum packet_result ret;
+
+  if (remote_protocol_packets[PACKET_QTDDCsrc].support == PACKET_DISABLE)
+    return;
+
+  strcpy (buf, "QTDDCsrc:");
+  if (strlen (buf) + strlen (collect) * 2 >= BUF_SIZE)
+    error (_("Source string too long for buffer"));
+  bin2hex (collect, buf + strlen (buf), 0);
+
+  putpkt (buf);
+  getpkt (&rs->buf, &rs->buf_size, 0);
+  ret = packet_ok (rs->buf, &remote_protocol_packets[PACKET_QTDDCsrc]);
+  if (ret == PACKET_UNKNOWN)
+    warning (_("\
+Target does not support tracepoint default collect source download."));
+  else if (ret == PACKET_ERROR)
+    warning (_("Remote failure reply: %s"), rs->buf);
+}
+
 static int
 remote_can_download_tracepoint (void)
 {
@@ -11422,6 +11458,8 @@ Specify the serial device it is connecte
   remote_ops.to_can_run_breakpoint_commands = remote_can_run_breakpoint_commands;
   remote_ops.to_trace_init = remote_trace_init;
   remote_ops.to_download_tracepoint = remote_download_tracepoint;
+  remote_ops.to_download_tracepoint_default_collect
+    = remote_download_tracepoint_default_collect;
   remote_ops.to_can_download_tracepoint = remote_can_download_tracepoint;
   remote_ops.to_download_trace_state_variable
     = remote_download_trace_state_variable;
@@ -11644,6 +11682,36 @@ remote_upload_trace_state_variables (str
   return 0;
 }
 
+/* Request target upload default collect, alloc buf for it and put it
+   to COLLECTP. */
+
+static void
+remote_upload_trace_default_collect (char **collectp)
+{
+  struct remote_state *rs = get_remote_state ();
+  int collect_size;
+
+  if (remote_protocol_packets[PACKET_qTDC].support == PACKET_DISABLE)
+    return;
+
+  putpkt ("qTDC");
+  remote_get_noisy_reply (&rs->buf, &rs->buf_size);
+  if (strncmp (rs->buf, "DC", 2))
+    {
+      remote_protocol_packets[PACKET_qTDC].support = PACKET_DISABLE;
+      *collectp = NULL;
+      warning (_("\
+Target does not support tracepoint default collect upload."));
+      return;
+    }
+
+  remote_protocol_packets[PACKET_qTDC].support = PACKET_ENABLE;
+  collect_size = (strlen (rs->buf) - 2) / 2;
+  *collectp = xmalloc (collect_size + 1);
+  hex2bin (rs->buf + 2, *collectp, collect_size);
+  (*collectp)[collect_size] = '\0';
+}
+
 void
 _initialize_remote (void)
 {
@@ -12000,6 +12068,12 @@ Show the maximum size of the address (in
   add_packet_config_cmd (&remote_protocol_packets[PACKET_qXfer_btrace],
        "qXfer:btrace", "read-btrace", 0);
 
+  add_packet_config_cmd (&remote_protocol_packets[PACKET_QTDDCsrc],
+			 "QTDDCsrc", "set-default-collect", 1);
+
+  add_packet_config_cmd (&remote_protocol_packets[PACKET_qTDC],
+			 "qTDC", "get-default-collect", 1);
+
   /* Keep the old ``set remote Z-packet ...'' working.  Each individual
      Z sub-packet has its own set and show commands, but users may
      have sets to this variable in their .gdbinit files (or in their
--- a/target.c
+++ b/target.c
@@ -706,6 +706,7 @@ update_current_target (void)
       INHERIT (to_supports_string_tracing, t);
       INHERIT (to_trace_init, t);
       INHERIT (to_download_tracepoint, t);
+      INHERIT (to_download_tracepoint_default_collect, t);
       INHERIT (to_can_download_tracepoint, t);
       INHERIT (to_download_trace_state_variable, t);
       INHERIT (to_enable_tracepoint, t);
@@ -890,6 +891,9 @@ update_current_target (void)
   de_fault (to_download_tracepoint,
 	    (void (*) (struct bp_location *))
 	    tcomplain);
+  de_fault (to_download_tracepoint_default_collect,
+	    (void (*) (char *))
+	    tcomplain);
   de_fault (to_can_download_tracepoint,
 	    (int (*) (void))
 	    return_zero);
--- a/target.h
+++ b/target.h
@@ -748,6 +748,10 @@ struct target_ops
     /* Send full details of a tracepoint location to the target.  */
     void (*to_download_tracepoint) (struct bp_location *location);
 
+    /* Send full details of the list of expressions to collect by default
+       to the target.  */
+    void (*to_download_tracepoint_default_collect) (char *collect);
+
     /* Is the target able to download tracepoint locations in current
        state?  */
     int (*to_can_download_tracepoint) (void);
@@ -1725,6 +1729,9 @@ extern char *target_fileio_read_stralloc
 #define target_download_tracepoint(t) \
   (*current_target.to_download_tracepoint) (t)
 
+#define target_download_tracepoint_default_collect(collect) \
+  (*current_target.to_download_tracepoint_default_collect) (collect)
+
 #define target_can_download_tracepoint() \
   (*current_target.to_can_download_tracepoint) ()
 
--- a/tracepoint.c
+++ b/tracepoint.c
@@ -1796,6 +1796,8 @@ start_tracing (char *notes)
 
       t->number_on_target = 0;
 
+      target_download_tracepoint_default_collect (default_collect);
+
       for (loc = b->loc; loc; loc = loc->next)
 	{
 	  /* Since tracepoint locations are never duplicated, `inserted'
@@ -5660,6 +5662,18 @@ traceframe_available_memory (VEC(mem_ran
   return 0;
 }
 
+/* Not overwrite default collect If COLLECT is NULL or its size is 0.  */
+
+void
+trace_set_default_collect (char *collect)
+{
+  if (collect != NULL)
+    {
+      xfree (default_collect);
+      default_collect = collect;
+    }
+}
+
 /* Implementation of `sdata' variable.  */
 
 static const struct internalvar_funcs sdata_funcs =
--- a/tracepoint.h
+++ b/tracepoint.h
@@ -412,4 +412,6 @@ extern struct traceframe_info *parse_tra
 extern int traceframe_available_memory (VEC(mem_range_s) **result,
 					CORE_ADDR memaddr, ULONGEST len);
 
+extern void trace_set_default_collect (char *collect);
+
 #endif	/* TRACEPOINT_H */