perf top: Improve the autosizing of column lenghts

When profiling C++ workloads the symbol name length can be
really big, so cap it before it garbles the result.

This builds upon the autosizing already present where we choose
to use the short, basename of DSOs instead of its long, full
pathname.

Reported-by: Pavel Krauz <krauz@cngroup.cz>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1268676230-9261-1-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/tools/perf/util/symbol.h b/tools/perf/util/symbol.h
index 280dadd..f30a374 100644
--- a/tools/perf/util/symbol.h
+++ b/tools/perf/util/symbol.h
@@ -110,9 +110,10 @@
 	u8		 sorted_by_name;
 	u8		 loaded;
 	u8		 build_id[BUILD_ID_SIZE];
-	u16		 long_name_len;
 	const char	 *short_name;
 	char	 	 *long_name;
+	u16		 long_name_len;
+	u16		 short_name_len;
 	char		 name[0];
 };