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-7.7.90.20140613/gdb/infrun.c
===================================================================
--- gdb-7.7.90.20140613.orig/gdb/infrun.c	2014-06-13 03:59:36.000000000 +0200
+++ gdb-7.7.90.20140613/gdb/infrun.c	2014-06-13 21:36:43.637294782 +0200
@@ -84,7 +84,7 @@ 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 void xdb_handle_command (char *args, int from_tty);
 
@@ -1742,7 +1742,8 @@ 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;
@@ -1760,7 +1761,7 @@ 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)
 {
   struct cleanup *old_cleanups = make_cleanup (resume_cleanups, 0);
   struct regcache *regcache = get_current_regcache ();
@@ -1800,9 +1801,13 @@ 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));
@@ -2188,6 +2193,7 @@ proceed (CORE_ADDR addr, enum gdb_signal
   struct thread_info *tp;
   CORE_ADDR pc;
   struct address_space *aspace;
+  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
@@ -2230,13 +2236,19 @@ proceed (CORE_ADDR addr, enum gdb_signal
 	   Note, we don't do this in reverse, because we won't
 	   actually be executing the breakpoint insn anyway.
 	   We'll be (un-)executing the previous instruction.  */
+	{
 	tp->stepping_over_breakpoint = 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.  */
+	{
 	tp->stepping_over_breakpoint = 1;
+	resume_step = RESUME_STEP_USER;
+	}
     }
   else
     {
@@ -2288,6 +2300,7 @@ proceed (CORE_ADDR addr, enum gdb_signal
 	  tp->prev_pc = regcache_read_pc (get_current_regcache ());
 	  switch_to_thread (step_over->ptid);
 	  tp = step_over;
+	  resume_step = RESUME_STEP_USER;
 	}
     }
 
@@ -2375,9 +2388,13 @@ proceed (CORE_ADDR addr, enum gdb_signal
   /* Reset to normal state.  */
   init_infwait_state ();
 
+  if (tp->control.trap_expected || step)
+    resume_step = RESUME_STEP_USER;
+  if (resume_step == RESUME_STEP_CONTINUE && bpstat_should_step ())
+    resume_step = RESUME_STEP_NEEDED;
+
   /* Resume inferior.  */
-  resume (tp->control.trap_expected || 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.  */
@@ -5359,13 +5376,16 @@ 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
+  if     ((tp->control.step_range_end
 	   && tp->control.step_resume_breakpoint == NULL)
-	  || tp->control.trap_expected
-	  || bpstat_should_step ());
+	  || tp->control.trap_expected)
+    return RESUME_STEP_USER;
+  if        (bpstat_should_step ())
+    return RESUME_STEP_NEEDED;
+  return RESUME_STEP_CONTINUE;
 }
 
 /* Inferior has stepped into a subroutine call with source code that
Index: gdb-7.7.90.20140613/gdb/linux-nat.c
===================================================================
--- gdb-7.7.90.20140613.orig/gdb/linux-nat.c	2014-06-13 03:59:37.000000000 +0200
+++ gdb-7.7.90.20140613/gdb/linux-nat.c	2014-06-13 21:31:19.449949814 +0200
@@ -2709,7 +2709,11 @@ 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-7.7.90.20140613/gdb/linux-nat.h
===================================================================
--- gdb-7.7.90.20140613.orig/gdb/linux-nat.h	2014-06-13 03:59:37.000000000 +0200
+++ gdb-7.7.90.20140613/gdb/linux-nat.h	2014-06-13 21:31:19.449949814 +0200
@@ -18,6 +18,7 @@
    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
 
 #include "target.h"
+#include "infrun.h"
 
 #include <signal.h>
 
@@ -59,8 +60,8 @@ 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.  */
Index: gdb-7.7.90.20140613/gdb/infrun.h
===================================================================
--- gdb-7.7.90.20140613.orig/gdb/infrun.h	2014-06-13 03:59:36.000000000 +0200
+++ gdb-7.7.90.20140613/gdb/infrun.h	2014-06-13 21:31:19.449949814 +0200
@@ -89,7 +89,14 @@ extern void proceed (CORE_ADDR, enum gdb
 
 /* 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);
 
diff --git a/gdb/testsuite/gdb.threads/signal-while-stepping-over-bp-other-thread.exp b/gdb/testsuite/gdb.threads/signal-while-stepping-over-bp-other-thread.exp
index 2a30604..ee1fd11 100644
--- a/gdb/testsuite/gdb.threads/signal-while-stepping-over-bp-other-thread.exp
+++ b/gdb/testsuite/gdb.threads/signal-while-stepping-over-bp-other-thread.exp
@@ -97,7 +97,7 @@ gdb_test "set debug infrun 1"
 
 gdb_test \
     "step" \
-    ".*need to step-over.*resume \\(step=1.*signal arrived while stepping over breakpoint.*switching back to stepped thread.*stepped to a different line.*callme.*" \
+    ".*need to step-over.*resume \\(step=RESUME_STEP_USER.*signal arrived while stepping over breakpoint.*switching back to stepped thread.*stepped to a different line.*callme.*" \
     "step"
 
 set cnt_after [get_value "args\[$my_number\]" "get count after step"]