Re: ttrace: Protocal error

[Pedro Alves <pedro@codesourcery.com>]

[-- Attachment #1: Type: text/plain, Size: 660 bytes --]

On Saturday 09 August 2008 15:51:16, Pedro Alves wrote:
> Also, when we detect a TTEVT_LWP_CREATE, TTEVT_LWP_EXIT or
> TTEVT_LWP_TERMINATE, The ttrace docs indicate that only one lwp is
> stopped.  There's no reason to stop all lwps, and return
> TARGET_WAITKING_SPURIOUS, only to resume all lwps again.
> This just adds overhead and messes more with the
> scheduling of the inferior than needed.  We could just resume
> the stopped lwp, and return TARGET_WAITKIND_IGNORE.

Here's a patch to do this.  It applies on top of the other I just sent,
which itself applied on top of my other patch to always register
the main thread.

-- 
Pedro Alves

[-- Attachment #2: fix_daves_bug_part_2.diff --]
[-- Type: text/x-diff, Size: 2720 bytes --]

2008-08-09  Pedro Alves  <pedro@codesourcery.com>

	* inf-ttrace.c (inf_ttrace_wait): On TTEVT_LWP_CREATE and
	LWP_TERMINATE, resume the caller thread.  On TTEVT_LWP_CREATE,
	TTEVT_LWP_EXIT and TTEVT_LWP_TERMINATE, don't stop the whole
	process, and return TARGET_WAITKIND_IGNORE.

---
 gdb/inf-ttrace.c |   26 ++++++++++++++++++++------
 1 file changed, 20 insertions(+), 6 deletions(-)

Index: src/gdb/inf-ttrace.c
===================================================================
--- src.orig/gdb/inf-ttrace.c	2008-08-09 23:15:40.000000000 +0100
+++ src/gdb/inf-ttrace.c	2008-08-09 23:15:53.000000000 +0100
@@ -1041,7 +1041,12 @@ inf_ttrace_wait (ptid_t ptid, struct tar
 	      sizeof (struct inf_ttrace_private_thread_info));
       inf_ttrace_num_lwps++;
       ptid = ptid_build (tts.tts_pid, tts.tts_lwpid, 0);
-      break;
+      /* Let the lwp_create-caller thread continue.  */
+      ttrace (TT_LWP_CONTINUE, ptid_get_pid (ptid),
+              ptid_get_lwp (ptid), TT_NOPC, 0, 0);
+      /* Return without stopping the whole process.  */
+      ourstatus->kind = TARGET_WAITKIND_IGNORE;
+      return ptid;
 
     case TTEVT_LWP_EXIT:
       if (print_thread_events)
@@ -1050,22 +1055,31 @@ inf_ttrace_wait (ptid_t ptid, struct tar
       gdb_assert (ti != NULL);
       ((struct inf_ttrace_private_thread_info *)ti->private)->dying = 1;
       inf_ttrace_num_lwps--;
+      /* Let the thread really exit.  */
       ttrace (TT_LWP_CONTINUE, ptid_get_pid (ptid),
               ptid_get_lwp (ptid), TT_NOPC, 0, 0);
-      /* If we don't return -1 here, core GDB will re-add the thread.  */
-      ptid = minus_one_ptid;
-      break;
+      /* Return without stopping the whole process.  */
+      ourstatus->kind = TARGET_WAITKIND_IGNORE;
+      return ptid;
 
     case TTEVT_LWP_TERMINATE:
       lwpid = tts.tts_u.tts_thread.tts_target_lwpid;
       ptid = ptid_build (tts.tts_pid, lwpid, 0);
-      printf_filtered(_("[%s has been terminated]\n"), target_pid_to_str (ptid));
+      if (print_thread_events)
+	printf_unfiltered(_("[%s has been terminated]\n")
+			  target_pid_to_str (ptid));
       ti = find_thread_pid (ptid);
       gdb_assert (ti != NULL);
       ((struct inf_ttrace_private_thread_info *)ti->private)->dying = 1;
       inf_ttrace_num_lwps--;
+
+      /* Resume the lwp_terminate-caller thread.  */
       ptid = ptid_build (tts.tts_pid, tts.tts_lwpid, 0);
-      break;
+      ttrace (TT_LWP_CONTINUE, ptid_get_pid (ptid),
+              ptid_get_lwp (ptid), TT_NOPC, 0, 0);
+      /* Return without stopping the whole process.  */
+      ourstatus->kind = TARGET_WAITKIND_IGNORE;
+      return ptid;
 
     case TTEVT_SIGNAL:
       ourstatus->kind = TARGET_WAITKIND_STOPPED;