gdb/gdb-6.6-scheduler_locking-step-sw-watchpoints2.patch

2007-06-25  Jan Kratochvil  <jan.kratochvil@redhat.com>

	* inferior.h (enum resume_step): New definition.
	(resume): Change STEP parameter type to ENUM RESUME_STEP.
	* infrun.c (resume): Likewise.  Extend debug printing of the STEP
	parameter.  Lock the scheduler only for intentional stepping.
	(proceed): Replace the variable ONESTEP with tristate RESUME_STEP.
	Set the third RESUME_STEP state according to BPSTAT_SHOULD_STEP.
	(currently_stepping): Change the return type to ENUM RESUME_STEP.
	Return RESUME_STEP_NEEDED if it is just due to BPSTAT_SHOULD_STEP.
	* linux-nat.c (select_singlestep_lwp_callback): Do not focus on
	the software watchpoint events.
	* linux-nat.h (struct lwp_info): Redeclare STEP as ENUM RESUME_STEP.

2007-10-19  Jan Kratochvil  <jan.kratochvil@redhat.com>

	* infrun.c (proceed): RESUME_STEP initialized for non-stepping.
	RESUME_STEP set according to STEP only at the end of the function.

2008-02-24  Jan Kratochvil  <jan.kratochvil@redhat.com>

	Port to GDB-6.8pre.

Index: gdb-7.6.90.20140127/gdb/inferior.h
===================================================================
--- gdb-7.6.90.20140127.orig/gdb/inferior.h	2014-01-27 22:05:28.801895347 +0100
+++ gdb-7.6.90.20140127/gdb/inferior.h	2014-01-27 22:33:45.230157813 +0100
@@ -155,7 +155,15 @@ extern void reopen_exec_file (void);
 /* The `resume' routine should only be called in special circumstances.
    Normally, use `proceed', which handles a lot of bookkeeping.  */
 
-extern void resume (int, enum gdb_signal);
+enum resume_step
+  {
+    /* currently_stepping () should return non-zero for non-continue.  */
+    RESUME_STEP_CONTINUE = 0,
+    RESUME_STEP_USER,		/* Stepping is intentional by the user.  */
+    RESUME_STEP_NEEDED		/* Stepping only for software watchpoints.  */
+  };
+
+extern void resume (enum resume_step, enum gdb_signal);
 
 extern ptid_t user_visible_resume_ptid (int step);
 
Index: gdb-7.6.90.20140127/gdb/infrun.c
===================================================================
--- gdb-7.6.90.20140127.orig/gdb/infrun.c	2014-01-27 22:05:28.804895349 +0100
+++ gdb-7.6.90.20140127/gdb/infrun.c	2014-01-27 22:35:12.781224279 +0100
@@ -83,7 +83,7 @@ static int follow_fork (void);
 static void set_schedlock_func (char *args, int from_tty,
 				struct cmd_list_element *c);
 
-static int currently_stepping (struct thread_info *tp);
+static enum resume_step currently_stepping (struct thread_info *tp);
 
 static int currently_stepping_or_nexting_callback (struct thread_info *tp,
 						   void *data);
@@ -1699,7 +1699,8 @@ user_visible_resume_ptid (int step)
     }
   else if ((scheduler_mode == schedlock_on)
 	   || (scheduler_mode == schedlock_step
-	       && (step || singlestep_breakpoints_inserted_p)))
+	       && (step == RESUME_STEP_USER
+		   || singlestep_breakpoints_inserted_p)))
     {
       /* User-settable 'scheduler' mode requires solo thread resume.  */
       resume_ptid = inferior_ptid;
@@ -1717,7 +1718,7 @@ user_visible_resume_ptid (int step)
    STEP nonzero if we should step (zero to continue instead).
    SIG is the signal to give the inferior (zero for none).  */
 void
-resume (int step, enum gdb_signal sig)
+resume (enum resume_step step, enum gdb_signal sig)
 {
   int should_resume = 1;
   struct cleanup *old_cleanups = make_cleanup (resume_cleanups, 0);
@@ -1750,9 +1751,13 @@ resume (int step, enum gdb_signal sig)
 
   if (debug_infrun)
     fprintf_unfiltered (gdb_stdlog,
-			"infrun: resume (step=%d, signal=%s), "
+			"infrun: resume (step=%s, signal=%s), "
 			"trap_expected=%d, current thread [%s] at %s\n",
-			step, gdb_signal_to_symbol_string (sig),
+			(step == RESUME_STEP_CONTINUE
+			 ? "RESUME_STEP_CONTINUE"
+			 : (step == RESUME_STEP_USER ? "RESUME_STEP_USER"
+						     : "RESUME_STEP_NEEDED")),
+			gdb_signal_to_symbol_string (sig),
 			tp->control.trap_expected,
 			target_pid_to_str (inferior_ptid),
 			paddress (gdbarch, pc));
@@ -2147,7 +2152,7 @@ proceed (CORE_ADDR addr, enum gdb_signal
   CORE_ADDR pc;
   struct address_space *aspace;
   /* GDB may force the inferior to step due to various reasons.  */
-  int force_step = 0;
+  enum resume_step resume_step = RESUME_STEP_CONTINUE;
 
   /* If we're stopped at a fork/vfork, follow the branch set by the
      "set follow-fork-mode" command; otherwise, we'll just proceed
@@ -2187,13 +2192,13 @@ proceed (CORE_ADDR addr, enum gdb_signal
 	   actually be executing the breakpoint insn anyway.
 	   We'll be (un-)executing the previous instruction.  */
 
-	force_step = 1;
+	resume_step = RESUME_STEP_USER;
       else if (gdbarch_single_step_through_delay_p (gdbarch)
 	       && gdbarch_single_step_through_delay (gdbarch,
 						     get_current_frame ()))
 	/* We stepped onto an instruction that needs to be stepped
 	   again before re-inserting the breakpoint, do so.  */
-	force_step = 1;
+	resume_step = RESUME_STEP_USER;
     }
   else
     {
@@ -2225,13 +2230,13 @@ proceed (CORE_ADDR addr, enum gdb_signal
 	 is required it returns TRUE and sets the current thread to
 	 the old thread.  */
       if (prepare_to_proceed (step))
-	force_step = 1;
+	resume_step = RESUME_STEP_USER;
     }
 
   /* prepare_to_proceed may change the current thread.  */
   tp = inferior_thread ();
 
-  if (force_step)
+  if (resume_step == RESUME_STEP_USER)
     {
       tp->control.trap_expected = 1;
       /* If displaced stepping is enabled, we can step over the
@@ -2318,9 +2323,13 @@ proceed (CORE_ADDR addr, enum gdb_signal
   /* Reset to normal state.  */
   init_infwait_state ();
 
+  if (step)
+    resume_step = RESUME_STEP_USER;
+  if (resume_step == RESUME_STEP_CONTINUE && bpstat_should_step ())
+    resume_step = RESUME_STEP_NEEDED;
+
   /* Resume inferior.  */
-  resume (force_step || step || bpstat_should_step (),
-	  tp->suspend.stop_signal);
+  resume (resume_step, tp->suspend.stop_signal);
 
   /* Wait for it to stop (if not standalone)
      and in any case decode why it stopped, and act accordingly.  */
@@ -5332,13 +5341,18 @@ switch_back_to_stepped_thread (struct ex
 
 /* Is thread TP in the middle of single-stepping?  */
 
-static int
+static enum resume_step
 currently_stepping (struct thread_info *tp)
 {
-  return ((tp->control.step_range_end
-	   && tp->control.step_resume_breakpoint == NULL)
-	  || tp->control.trap_expected
-	  || bpstat_should_step ());
+  if ((tp->control.step_range_end
+       && tp->control.step_resume_breakpoint == NULL)
+      || tp->control.trap_expected)
+    return RESUME_STEP_USER;
+
+  if (bpstat_should_step ())
+    return RESUME_STEP_NEEDED;
+
+  return RESUME_STEP_CONTINUE;
 }
 
 /* Returns true if any thread *but* the one passed in "data" is in the
Index: gdb-7.6.90.20140127/gdb/linux-nat.c
===================================================================
--- gdb-7.6.90.20140127.orig/gdb/linux-nat.c	2014-01-27 22:05:28.806895350 +0100
+++ gdb-7.6.90.20140127/gdb/linux-nat.c	2014-01-27 22:33:45.330157889 +0100
@@ -2697,7 +2697,11 @@ static int
 select_singlestep_lwp_callback (struct lwp_info *lp, void *data)
 {
   if (lp->last_resume_kind == resume_step
-      && lp->status != 0)
+      && lp->status != 0
+      /* We do not focus on software watchpoints as we would not catch
+	 STEPPING_PAST_SINGLESTEP_BREAKPOINT breakpoints in some other thread
+	 as they would remain pending due to `Push back breakpoint for %s'.  */
+      && lp->step == RESUME_STEP_USER)
     return 1;
   else
     return 0;
Index: gdb-7.6.90.20140127/gdb/linux-nat.h
===================================================================
--- gdb-7.6.90.20140127.orig/gdb/linux-nat.h	2014-01-27 22:05:28.807895351 +0100
+++ gdb-7.6.90.20140127/gdb/linux-nat.h	2014-01-27 22:33:45.334157892 +0100
@@ -59,8 +59,8 @@ struct lwp_info
   /* If non-zero, a pending wait status.  */
   int status;
 
-  /* Non-zero if we were stepping this LWP.  */
-  int step;
+  /* The kind of stepping of this LWP.  */
+  enum resume_step step;
 
   /* STOPPED_BY_WATCHPOINT is non-zero if this LWP stopped with a data
      watchpoint trap.  */