Index: NEWS
===================================================================
RCS file: /cvs/src/src/gdb/NEWS,v
retrieving revision 1.362
diff -p -r1.362 NEWS
*** NEWS	8 Mar 2010 19:20:38 -0000	1.362
--- NEWS	16 Mar 2010 21:27:00 -0000
*************** Renesas RX			rx
*** 114,120 ****
    tracing run at the moment that it was saved.  To create a trace
    file, use "tsave <filename>", and to use it, do "target tfile
    <name>".
!   
  * Changed commands
  
  disassemble
--- 114,127 ----
    tracing run at the moment that it was saved.  To create a trace
    file, use "tsave <filename>", and to use it, do "target tfile
    <name>".
! 
!   ** Circular trace buffer
! 
!   You can ask the target agent to handle the trace buffer as a
!   circular buffer, discarding the oldest trace frames to make room for
!   newer ones, by setting circular-trace-buffer to 1.  This feature may
!   not be available for all target agents.
! 
  * Changed commands
  
  disassemble
*************** show disconnected-tracing
*** 215,220 ****
--- 222,234 ----
     loses its connection to GDB.  If 0, the target is to stop tracing
     upon disconnection.
  
+ set circular-trace-buffer
+ show circular-trace-buffer
+    If set to 1, the target is instructed to use a circular trace buffer
+    and discard the oldest trace frames instead of stopping the trace due
+    to a full trace buffer.  If set to 0, the trace stops when the buffer
+    fills up.
+ 
  set script-extension off|soft|strict
  show script-extension
     If set to "off", the debugger does not perform any script language
*************** qTV
*** 258,263 ****
--- 272,280 ----
  QTDisconnected
     Set desired tracing behavior upon disconnection.
  
+ QTBuffer:circular
+    Set the trace buffer to be linear or circular.
+ 
  qTfP, qTsP
     Get data about the tracepoints currently in use.
  
Index: remote.c
===================================================================
RCS file: /cvs/src/src/gdb/remote.c,v
retrieving revision 1.389
diff -p -r1.389 remote.c
*** remote.c	7 Mar 2010 14:36:44 -0000	1.389
--- remote.c	16 Mar 2010 21:27:00 -0000
*************** remote_core_of_thread (struct target_ops
*** 9659,9664 ****
--- 9659,9676 ----
  }
  
  static void
+ remote_set_circular_trace_buffer (int val)
+ {
+   struct remote_state *rs = get_remote_state ();
+ 
+   sprintf (rs->buf, "QTBuffer:circular:%x", val);
+   putpkt (rs->buf);
+   remote_get_noisy_reply (&target_buf, &target_buf_size);
+   if (strcmp (target_buf, "OK"))
+     error (_("Target does not support this command."));
+ }
+ 
+ static void
  init_remote_ops (void)
  {
    remote_ops.to_shortname = "remote";
*************** Specify the serial device it is connecte
*** 9736,9741 ****
--- 9748,9754 ----
    remote_ops.to_upload_trace_state_variables = remote_upload_trace_state_variables;
    remote_ops.to_get_raw_trace_data = remote_get_raw_trace_data;
    remote_ops.to_set_disconnected_tracing = remote_set_disconnected_tracing;
+   remote_ops.to_set_circular_trace_buffer = remote_set_circular_trace_buffer;
    remote_ops.to_core_of_thread = remote_core_of_thread;
  }
  
Index: target.c
===================================================================
RCS file: /cvs/src/src/gdb/target.c,v
retrieving revision 1.242
diff -p -r1.242 target.c
*** target.c	12 Mar 2010 03:54:45 -0000	1.242
--- target.c	16 Mar 2010 21:27:00 -0000
*************** update_current_target (void)
*** 659,664 ****
--- 659,665 ----
        INHERIT (to_upload_trace_state_variables, t);
        INHERIT (to_get_raw_trace_data, t);
        INHERIT (to_set_disconnected_tracing, t);
+       INHERIT (to_set_circular_trace_buffer, t);
        INHERIT (to_magic, t);
        /* Do not inherit to_memory_map.  */
        /* Do not inherit to_flash_erase.  */
*************** update_current_target (void)
*** 848,854 ****
  	    tcomplain);
    de_fault (to_set_disconnected_tracing,
  	    (void (*) (int))
! 	    tcomplain);
  #undef de_fault
  
    /* Finally, position the target-stack beneath the squashed
--- 849,858 ----
  	    tcomplain);
    de_fault (to_set_disconnected_tracing,
  	    (void (*) (int))
! 	    target_ignore);
!   de_fault (to_set_circular_trace_buffer,
! 	    (void (*) (int))
! 	    target_ignore);
  #undef de_fault
  
    /* Finally, position the target-stack beneath the squashed
Index: target.h
===================================================================
RCS file: /cvs/src/src/gdb/target.h,v
retrieving revision 1.173
diff -p -r1.173 target.h
*** target.h	22 Feb 2010 23:35:16 -0000	1.173
--- target.h	16 Mar 2010 21:27:00 -0000
*************** struct target_ops
*** 664,669 ****
--- 664,670 ----
      /* Set the target's tracing behavior in response to unexpected
         disconnection - set VAL to 1 to keep tracing, 0 to stop.  */
      void (*to_set_disconnected_tracing) (int val);
+     void (*to_set_circular_trace_buffer) (int val);
  
      /* Return the processor core that thread PTID was last seen on.
         This information is updated only when:
*************** extern int target_search_memory (CORE_AD
*** 1359,1364 ****
--- 1360,1368 ----
  #define target_set_disconnected_tracing(val) \
    (*current_target.to_set_disconnected_tracing) (val)
  
+ #define	target_set_circular_trace_buffer(val)	\
+   (*current_target.to_set_circular_trace_buffer) (val)
+ 
  /* Command logging facility.  */
  
  #define target_log_command(p)						\
Index: tracepoint.c
===================================================================
RCS file: /cvs/src/src/gdb/tracepoint.c,v
retrieving revision 1.146
diff -p -r1.146 tracepoint.c
*** tracepoint.c	12 Mar 2010 03:54:45 -0000	1.146
--- tracepoint.c	16 Mar 2010 21:27:00 -0000
*************** char *default_collect = "";
*** 153,158 ****
--- 153,163 ----
  
  static int disconnected_tracing;
  
+ /* This variable controls whether we ask the target for a linear or
+    circular trace buffer.  */
+ 
+ static int circular_trace_buffer;
+ 
  /* ======= Important command functions: ======= */
  static void trace_actions_command (char *, int);
  static void trace_start_command (char *, int);
*************** trace_start_command (char *args, int fro
*** 1560,1565 ****
--- 1565,1573 ----
    
    /* Tell target to treat text-like sections as transparent.  */
    target_trace_set_readonly_regions ();
+   /* Set some mode flags.  */
+   target_set_disconnected_tracing (disconnected_tracing);
+   target_set_circular_trace_buffer (circular_trace_buffer);
  
    /* Now insert traps and begin collecting data.  */
    target_trace_start ();
*************** trace_status_command (char *args, int fr
*** 1649,1664 ****
  	}
      }
  
!   if (ts->traceframe_count >= 0)
      {
        printf_filtered (_("Collected %d trace frames.\n"),
  		       ts->traceframe_count);
      }
  
!   if (ts->buffer_free)
      {
!       printf_filtered (_("Trace buffer has %llu bytes free.\n"),
! 		       ts->buffer_free);
      }
  
    /* Now report on what we're doing with tfind.  */
--- 1657,1689 ----
  	}
      }
  
!   if (ts->traceframes_created >= 0)
!     {
!       printf_filtered (_("Buffer contains %d trace frames (of %d created total).\n"),
! 		       ts->traceframe_count, ts->traceframes_created);
!     }
!   else if (ts->traceframe_count >= 0)
      {
        printf_filtered (_("Collected %d trace frames.\n"),
  		       ts->traceframe_count);
      }
  
!   if (ts->buffer_free >= 0)
      {
!       if (ts->buffer_size >= 0)
! 	{
! 	  printf_filtered (_("Trace buffer has %d bytes of %d bytes free"),
! 			   ts->buffer_free, ts->buffer_size);
! 	  if (ts->buffer_size > 0)
! 	    printf_filtered (_(" (%d%% full)"),
! 			     ((int) ((((long long) (ts->buffer_size
! 						    - ts->buffer_free)) * 100)
! 				     / ts->buffer_size)));
! 	  printf_filtered (_(".\n"));
! 	}
!       else
! 	printf_filtered (_("Trace buffer has %d bytes free.\n"),
! 			 ts->buffer_free);
      }
  
    /* Now report on what we're doing with tfind.  */
*************** trace_save_command (char *args, int from
*** 2419,2428 ****
    fprintf (fp, "R %x\n", trace_regblock_size);
  
    /* Write out status of the tracing run (aka "tstatus" info).  */
!   fprintf (fp, "status %c;%s:%x;tframes:%x;tfree:%llx\n",
  	   (ts->running ? '1' : '0'),
! 	   stop_reason_names[ts->stop_reason], ts->stopping_tracepoint,
! 	   ts->traceframe_count, ts->buffer_free);
  
    /* Note that we want to upload tracepoints and save those, rather
       than simply writing out the local ones, because the user may have
--- 2444,2461 ----
    fprintf (fp, "R %x\n", trace_regblock_size);
  
    /* Write out status of the tracing run (aka "tstatus" info).  */
!   fprintf (fp, "status %c;%s:%x",
  	   (ts->running ? '1' : '0'),
!  	   stop_reason_names[ts->stop_reason], ts->stopping_tracepoint);
!   if (ts->traceframe_count >= 0)
!     fprintf (fp, ";tframes:%x", ts->traceframe_count);
!   if (ts->traceframes_created >= 0)
!     fprintf (fp, ";tcreated:%x", ts->traceframes_created);
!   if (ts->buffer_free >= 0)
!     fprintf (fp, ";tfree:%x", ts->buffer_free);
!   if (ts->buffer_size >= 0)
!     fprintf (fp, ";tsize:%x", ts->buffer_size);
!   fprintf (fp, "\n");
  
    /* Note that we want to upload tracepoints and save those, rather
       than simply writing out the local ones, because the user may have
*************** set_disconnected_tracing (char *args, in
*** 2527,2532 ****
--- 2560,2572 ----
    send_disconnected_tracing_value (disconnected_tracing);
  }
  
+ static void
+ set_circular_trace_buffer (char *args, int from_tty,
+ 			   struct cmd_list_element *c)
+ {
+   target_set_circular_trace_buffer (circular_trace_buffer);
+ }
+ 
  /* Convert the memory pointed to by mem into hex, placing result in buf.
   * Return a pointer to the last char put in buf (null)
   * "stolen" from sparc-stub.c
*************** parse_trace_status (char *line, struct t
*** 3040,3045 ****
--- 3080,3090 ----
    ts->running_known = 1;
    ts->running = (*p++ == '1');
    ts->stop_reason = trace_stop_reason_unknown;
+   ts->traceframe_count = -1;
+   ts->traceframes_created = -1;
+   ts->buffer_free = -1;
+   ts->buffer_size = -1;
+ 
    while (*p++)
      {
        p1 = strchr (p, ':');
*************** Status line: '%s'\n"), p, line);
*** 3067,3082 ****
  	  p = unpack_varlen_hex (++p1, &val);
  	  ts->stop_reason = tstop_command;
  	}
!       if (strncmp (p, "tframes", p1 - p) == 0)
  	{
  	  p = unpack_varlen_hex (++p1, &val);
  	  ts->traceframe_count = val;
  	}
!       if (strncmp (p, "tfree", p1 - p) == 0)
  	{
  	  p = unpack_varlen_hex (++p1, &val);
  	  ts->buffer_free = val;
  	}
        else
  	{
  	  /* Silently skip unknown optional info.  */
--- 3112,3137 ----
  	  p = unpack_varlen_hex (++p1, &val);
  	  ts->stop_reason = tstop_command;
  	}
!       else if (strncmp (p, "tframes", p1 - p) == 0)
  	{
  	  p = unpack_varlen_hex (++p1, &val);
  	  ts->traceframe_count = val;
  	}
!       else if (strncmp (p, "tcreated", p1 - p) == 0)
! 	{
! 	  p = unpack_varlen_hex (++p1, &val);
! 	  ts->traceframes_created = val;
! 	}
!       else if (strncmp (p, "tfree", p1 - p) == 0)
  	{
  	  p = unpack_varlen_hex (++p1, &val);
  	  ts->buffer_free = val;
  	}
+       else if (strncmp (p, "tsize", p1 - p) == 0)
+ 	{
+ 	  p = unpack_varlen_hex (++p1, &val);
+ 	  ts->buffer_size = val;
+ 	}
        else
  	{
  	  /* Silently skip unknown optional info.  */
*************** trace data collected in the meantime."),
*** 3800,3805 ****
--- 3855,3872 ----
  			   &setlist,
  			   &showlist);
  
+   add_setshow_boolean_cmd ("circular-trace-buffer", no_class,
+ 			   &circular_trace_buffer, _("\
+ Set target's use of circular trace buffer."), _("\
+ Show target's use of circular trace buffer."), _("\
+ Use this to make the trace buffer into a circular buffer,\n\
+ which will discard traceframes (oldest first) instead of filling\n\
+ up and stopping the trace run."),
+ 			   set_circular_trace_buffer,
+ 			   NULL,
+ 			   &setlist,
+ 			   &showlist);
+ 
    init_tfile_ops ();
  
    add_target (&tfile_ops);
Index: tracepoint.h
===================================================================
RCS file: /cvs/src/src/gdb/tracepoint.h,v
retrieving revision 1.22
diff -p -r1.22 tracepoint.h
*** tracepoint.h	24 Feb 2010 01:06:28 -0000	1.22
--- tracepoint.h	16 Mar 2010 21:27:00 -0000
*************** struct trace_status
*** 95,105 ****
  
    int stopping_tracepoint;
  
    int traceframe_count;
  
!   unsigned long long buffer_size;
  
!   unsigned long long buffer_free;
  };
  
  struct trace_status *current_trace_status (void);
--- 95,115 ----
  
    int stopping_tracepoint;
  
+   /* Number of traceframes currently in the buffer.  */
+ 
    int traceframe_count;
  
!   /* Number of traceframes created since start of run.  */
! 
!   int traceframes_created;
! 
!   /* Total size of the target's trace buffer.  */
! 
!   int buffer_size;
! 
!   /* Unused bytes left in the target's trace buffer.  */
  
!   int buffer_free;
  };
  
  struct trace_status *current_trace_status (void);
Index: doc/gdb.texinfo
===================================================================
RCS file: /cvs/src/src/gdb/doc/gdb.texinfo,v
retrieving revision 1.680
diff -p -r1.680 gdb.texinfo
*** doc/gdb.texinfo	12 Mar 2010 19:15:52 -0000	1.680
--- doc/gdb.texinfo	16 Mar 2010 21:27:01 -0000
*************** which to specify that tracepoint.  This 
*** 9836,9841 ****
--- 9836,9868 ----
  necessarily heuristic, and it may result in useless tracepoints being
  created; you may simply delete them if they are of no use.
  
+ @cindex circular trace buffer
+ If your target agent supports a @dfn{circular trace buffer}, then you
+ can run a trace experiment indefinitely without filling the trace
+ buffer; when space runs out, the agent deletes already-collected trace
+ frames, oldest first, until there is enough room to continue
+ collecting.  This is especially useful if your tracepoints are being
+ hit too often and terminating tracing too soon.  To ask for a circular
+ trace buffer, simply set @samp{circular_trace_buffer} to 1.  You can
+ set this at any time, including during tracing; if the agent can do
+ it, it will change buffer handling on the fly, otherwise it will not
+ take effect until the next run.
+ 
+ @table @code
+ @item set circular-trace-buffer on
+ @itemx set circular-trace-buffer off
+ @kindex set circular-trace-buffer
+ Choose whether a tracing run should use a linear or circular buffer
+ for trace data.  A linear buffer will not lose any trace data, but may
+ fill up prematurely, while a circular buffer will discard old trace
+ data, but it will have always room for the latest tracepoint hits.
+ 
+ @item show circular-trace-buffer
+ @kindex show circular-trace-buffer
+ Show the current choice for the trace buffer.
+ 
+ @end table
+ 
  @node Tracepoint Restrictions
  @subsection Tracepoint Restrictions
  
*************** encoded).  @value{GDBN} will continue to
*** 30603,30608 ****
--- 30630,30636 ----
  @end table
  
  @item qTBuffer
+ @item QTBuffer
  @item QTDisconnected
  @itemx QTDP
  @itemx QTDV
*************** continue the tracing run, while 0 tells 
*** 31087,31098 ****
  @item qTStatus
  Ask the stub if there is a trace experiment running right now.
  
! Replies:
  @table @samp
! @item T0
! There is no trace experiment running.
! @item T1
! There is a trace experiment running.
  @end table
  
  @item qTV:@var{var}
--- 31115,31176 ----
  @item qTStatus
  Ask the stub if there is a trace experiment running right now.
  
! The reply has the form:
! 
! @table @samp
! 
! @item T@var{running}@r{[};@var{field}@r{]}@dots{}
! @var{running} is a single digit @code{1} if the trace is presently
! running, or @code{0} if not.  It is followed by optional fields that
! an agent may use to report additional status. 
! 
! @end table
! 
! If the trace is not running, the agent may report any of several
! explanations as one of the optional fields:
! 
! @table @samp
! 
! @item tnotrun:0
! No trace has been run yet.
! 
! @item tstop:0
! The trace was stopped by a user-originated stop command.
! 
! @item tfull:0
! The trace stopped because the trace buffer filled up.
! 
! @item tdisconnected:0
! The trace stopped because @value{GDBN} disconnected from the target.
! 
! @item tpasscount:@var{tpnum}
! The trace stopped because tracepoint @var{tpnum} exceeded its pass count.
! 
! @item tunknown:0
! The trace stopped for some other reason.
! 
! @end table
! 
! Additional optional fields supply statistical information.  Although
! not required, they are extremely useful for users monitoring the
! progress of a trace run.  If a trace has stopped, and these numbers
! are reported, they must reflect the state of the just-stopped trace.
! 
  @table @samp
! 
! @item tframes:@var{n}
! The number of trace frames in the buffer.
! 
! @item tcreated:@var{n}
! The total number of trace frames created during the run. This may
! be larger than the trace frame count, if the buffer is circular.
! 
! @item tsize:@var{n}
! The total size of the trace buffer.
! 
! @item tfree:@var{n}
! The number of bytes still unused in the buffer.
! 
  @end table
  
  @item qTV:@var{var}
*************** in a packet; it is not an error to retur
*** 31147,31152 ****
--- 31225,31234 ----
  A reply consisting of just @code{l} indicates that no bytes are
  available.
  
+ @item QTBuffer:circular:@var{value}
+ This packet directs the target to use a circular trace buffer if
+ @var{value} is 1, or a linear buffer if the value is 0.
+ 
  @end table
  
  @node Host I/O Packets