perf record: Don't call newt functions when not initialized

When processing events we want to give visual feedback to the user when
using the newt browser, so there are ui_progress calls in
__perf_session__process_events, but those should check if newt is being
used.
Reported-by: NSrikar Dronamraju <srikar@linux.vnet.ibm.com>
Tested-by: NSrikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>,
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <20100609123530.GB9471@ghostprotocols.net>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/util/newt.c

@@ -43,6 +43,9 @@ struct ui_progress *ui_progress__new(const char *title, u64 total)
 
 	if (self != NULL) {
 		int cols;
+
+		if (use_browser <= 0)	
+			return self;
 		newtGetScreenSize(&cols, NULL);
 		cols -= 4;
 		newtCenteredWindow(cols, 1, title);
@@ -67,14 +70,22 @@ struct ui_progress *ui_progress__new(const char *title, u64 total)
 
 void ui_progress__update(struct ui_progress *self, u64 curr)
 {
+	/*
+	 * FIXME: We should have a per UI backend way of showing progress,
+	 * stdio will just show a percentage as NN%, etc.
+	 */
+	if (use_browser <= 0)
+		return;
 	newtScaleSet(self->scale, curr);
 	newtRefresh();
 }
 
 void ui_progress__delete(struct ui_progress *self)
 {
+	if (use_browser > 0) {
 		newtFormDestroy(self->form);
 		newtPopWindow();
+	}
 	free(self);
 }