perf script python: Add Python3 support to stackcollapse.py

Support both Python2 and Python3 in the stackcollapse.py script

There may be differences in the ordering of output lines due to
differences in dictionary ordering etc.  However the format within lines
should be unchanged.

The use of 'from __future__' implies the minimum supported Python2 version
is now v2.6

Signed-off-by: Tony Jones <[email protected]>
Cc: Paolo Bonzini <[email protected]> <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Seeteena Thoufeek <[email protected]>
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

diff --git a/tools/perf/scripts/python/stackcollapse.py b/tools/perf/scripts/python/stackcollapse.py
index 1697b5e18c9622bdc82f7f9355745febb0a28705..5e703efaddcc2472f812c0a386b8b1e88f1a4094 100755 (executable)
--- a/tools/perf/scripts/python/stackcollapse.py
+++ b/tools/perf/scripts/python/stackcollapse.py
@@ -19,6 +19,8 @@
 # Written by Paolo Bonzini <[email protected]>
 # Based on Brendan Gregg's stackcollapse-perf.pl script.
 
+from __future__ import print_function
+
 import os
 import sys
 from collections import defaultdict
@@ -120,7 +122,6 @@ def process_event(param_dict):
     lines[stack_string] = lines[stack_string] + 1
 
 def trace_end():
-    list = lines.keys()
-    list.sort()
+    list = sorted(lines)
     for stack in list:
-        print "%s %d" % (stack, lines[stack])
+        print("%s %d" % (stack, lines[stack]))