Hi All,
This patch adds support for QTBuffer:size in gdbserver and adds  
commands in gdb to use this packet to change the trace buffer size.   
The default value of the buffer size in gdb is -1 which means that  
target will use whatever size it likes.

I notice that there are some tests that are using "maint packet" to  
send QTBuffer:size. I was not sure what to do with them so I have left  
them alone. If reviewers suggest, I can update/remove them.

Regards,
Abid

2012-02-18  Stan Shebs  <stan@codesourcery.com>
	    Hafiz Abid Qadeer  <abidh@codesourcery.com>

	gdb/
	* NEWS: Mention set and show trace-buffer-size commands.
	* target.h (struct target_ops): New method
	to_set_trace_buffer_size.
	(target_set_trace_buffer_size): New macro.
	* target.c (update_current_target): Set up new method.
	* tracepoint.c (trace_buffer_size): New global.
	(start_tracing): Send it to the target.
	(set_trace_buffer_size): New function.
	(_initialize_tracepoint): Add new setshow for trace-buffer-size.
	* remote.c (remote_set_trace_buffer_size): New function.
	(_initialize_remote): Use it.
	(remote_set_trace_notes): Handle no-op case better.

	gdb/gdbserver/
	* tracepoint.c (trace_buffer_size): New global.
	(init_trace_buffer): Change to one-argument function, add
	realloc option.
	(handle_tracepoint_general_set): Call cmd_bigqtbuffer_size to
	handle QTBuffer:size packet.
	(cmd_bigqtbuffer_size): New function.
	(initialize_tracepoint): Default to a smaller buffer.

	gdb/doc/
	* gdb.texinfo (Starting and Stopping Trace Experiments):  
Document
	trace-buffer-size set and show commands.
	(Tracepoint Packets): Document QTBuffer:size .

	gdb/testsuite/
	* gdb.trace/trace-buffer-size.exp: New file.
	* gdb.trace/trace-buffer-size.c: New file.