Add the gdb remote target operations for branch tracing.

We define the following packets:

  Qbtrace:bts         enable branch tracing for the current thread
                      returns "OK" or "Enn"

  Qbtrace:off         disable branch tracing for the current thread
                      returns "OK" or "Enn"

  qXfer:btrace:read   read the full branch trace data for the current thread

gdb/
	* target.h (enum target_object): Add TARGET_OBJECT_BTRACE.
	* remote.c: Include btrace.h.
	(struct btrace_target_info): New struct.
	(remote_supports_btrace): New function.
	(send_Qbtrace): New function.
	(remote_enable_btrace): New function.
	(remote_disable_btrace): New function.
	(remote_teardown_btrace): New function.
	(remote_read_btrace): New function.
	(init_remote_ops): Add btrace ops.
	(enum <unnamed>): Add btrace packets.
	(struct protocol_feature remote_protocol_features[]): Add btrace packets.
	(_initialize_remote): Add packet configuration for branch tracing.

gdbserver/
	* target.h (struct target_ops): Add btrace ops.
	(target_supports_btrace): New macro.
	(target_enable_btrace): New macro.
	(target_disable_btrace): New macro.
	(target_read_btrace): New macro.
	* gdbthread.h (struct thread_info): Add btrace field.
	* server.c: Include btrace-common.h.
	(handle_btrace_general_set): New function.
	(handle_btrace_enable): New function.
	(handle_btrace_disable): New function.
	(handle_general_set): Call handle_btrace_general_set.
	(handle_qxfer_btrace): New function.
	(struct qxfer qxfer_packets[]): Add btrace entry.
	* inferiors.c (remove_thread): Disable btrace.
	* linux-low: Include linux-btrace.h.
	(linux_low_enable_btrace): New function.
	(linux_low_read_btrace): New function.
	(linux_target_ops): Add btrace ops.
	* configure.srv (i[34567]86-*-linux*): Add linux-btrace.o.
	Add srv_linux_btrace=yes.
	(x86_64-*-linux*): Add linux-btrace.o.
	Add srv_linux_btrace=yes.
	* configure.ac: Define HAVE_LINUX_BTRACE.
	* config.in: Regenerated.
	* configure: Regenerated.

1 files changed, 29 insertions, 0 deletions

diff --git a/gdb/gdbserver/target.h b/gdb/gdbserver/target.h
index cc9a910..f257459 100644
--- a/gdb/gdbserver/target.h
+++ b/gdb/gdbserver/target.h
@@ -22,6 +22,8 @@
 #define TARGET_H
 
 struct emit_ops;
+struct btrace_target_info;
+struct buffer;
 
 /* Ways to "resume" a thread.  */
 
@@ -397,6 +399,21 @@ struct target_ops
 
   /* Return true if target supports debugging agent.  */
   int (*supports_agent) (void);
+
+  /* Check whether the target supports branch tracing.  */
+  int (*supports_btrace) (void);
+
+  /* Enable branch tracing for @ptid and allocate a branch trace target
+     information struct for reading and for disabling branch trace.  */
+  struct btrace_target_info *(*enable_btrace) (ptid_t ptid);
+
+  /* Disable branch tracing.  */
+  int (*disable_btrace) (struct btrace_target_info *tinfo);
+
+  /* Read branch trace data into buffer.  We use an int to specify the type
+     to break a cyclic dependency.  */
+  void (*read_btrace) (struct btrace_target_info *, struct buffer *, int type);
+
 };
 
 extern struct target_ops *the_target;
@@ -520,6 +537,18 @@ int kill_inferior (int);
   (the_target->supports_agent ? \
    (*the_target->supports_agent) () : 0)
 
+#define target_supports_btrace() \
+  (the_target->supports_btrace ? (*the_target->supports_btrace) () : 0)
+
+#define target_enable_btrace(ptid) \
+  (*the_target->enable_btrace) (ptid)
+
+#define target_disable_btrace(tinfo) \
+  (*the_target->disable_btrace) (tinfo)
+
+#define target_read_btrace(tinfo, buffer, type)	\
+  (*the_target->read_btrace) (tinfo, buffer, type)
+
 /* Start non-stop mode, returns 0 on success, -1 on failure.   */
 
 int start_non_stop (int nonstop);