Check lwp_signal_can_be_delivered for enqueue/dequeue pending signals

The enqueue and dequeue signals in linux_resume_one_lwp_throw use one
condition and its inverted one.  This patch is to move the condition
into a function lwp_signal_can_be_delivered, so that the next patch can
change the condition in one place.

gdb/gdbserver:

2016-03-18  Yao Qi  <yao.qi@linaro.org>

	* linux-low.c (lwp_signal_can_be_delivered): New function.
	(linux_resume_one_lwp_throw): Use lwp_signal_can_be_delivered.

2 files changed, 21 insertions, 10 deletions

diff --git a/gdb/gdbserver/ChangeLog b/gdb/gdbserver/ChangeLog
index b210971..a63d7fb 100644
--- a/gdb/gdbserver/ChangeLog
+++ b/gdb/gdbserver/ChangeLog
@@ -1,5 +1,10 @@
 2016-03-18  Yao Qi  <yao.qi@linaro.org>
 
+	* linux-low.c (lwp_signal_can_be_delivered): New function.
+	(linux_resume_one_lwp_throw): Use lwp_signal_can_be_delivered.
+
+2016-03-18  Yao Qi  <yao.qi@linaro.org>
+
 	* linux-low.c (linux_resume_one_lwp_throw): Set 'signal' to
 	0 if signal is enqueued.  Remove 'signal' from one debugging
 	message.  Move one debugging message to some lines below.
diff --git a/gdb/gdbserver/linux-low.c b/gdb/gdbserver/linux-low.c
index f267a96..7630f9f 100644
--- a/gdb/gdbserver/linux-low.c
+++ b/gdb/gdbserver/linux-low.c
@@ -4118,6 +4118,16 @@ single_step (struct lwp_info* lwp)
   return step;
 }
 
+/* The signal can be delivered to the inferior if we are not trying to
+   reinsert a breakpoint and not trying to finish a fast tracepoint
+   collect.  */
+
+static int
+lwp_signal_can_be_delivered (struct lwp_info *lwp)
+{
+  return (lwp->bp_reinsert == 0 && !lwp->collecting_fast_tracepoint);
+}
+
 /* Resume execution of LWP.  If STEP is nonzero, single-step it.  If
    SIGNAL is nonzero, give it that signal.  */
 
@@ -4157,13 +4167,12 @@ linux_resume_one_lwp_throw (struct lwp_info *lwp,
     }
 
   /* If we have pending signals or status, and a new signal, enqueue the
-     signal.  Also enqueue the signal if we are waiting to reinsert a
-     breakpoint; it will be picked up again below.  */
+     signal.  Also enqueue the signal if it can't be delivered to the
+     inferior right now.  */
   if (signal != 0
       && (lwp->status_pending_p
 	  || lwp->pending_signals != NULL
-	  || lwp->bp_reinsert != 0
-	  || fast_tp_collecting))
+	  || !lwp_signal_can_be_delivered (lwp)))
     {
       enqueue_pending_signal (lwp, signal, info);
 
@@ -4269,12 +4278,9 @@ linux_resume_one_lwp_throw (struct lwp_info *lwp,
 	}
     }
 
-  /* If we have pending signals, consume one unless we are trying to
-     reinsert a breakpoint or we're trying to finish a fast tracepoint
-     collect.  */
-  if (lwp->pending_signals != NULL
-      && lwp->bp_reinsert == 0
-      && fast_tp_collecting == 0)
+  /* If we have pending signals, consume one if it can be delivered to
+     the inferior.  */
+  if (lwp->pending_signals != NULL && lwp_signal_can_be_delivered (lwp))
     {
       struct pending_signals **p_sig;