perf: allow events to be specified as an iterable

client/profilers/perf/perf.py

Index: client/profilers/perf/perf.py
diff --git a/client/profilers/perf/perf.py b/client/profilers/perf/perf.py
index 211d562bdaea058341afad4fcbda3b65ec0e3664..e6f9bb71afd441cf1b42e416087e476b0d1b629f 100644
--- a/client/profilers/perf/perf.py
+++ b/client/profilers/perf/perf.py
@@ -13,8 +13,11 @@ from autotest_lib.client.bin import profiler, os_dep, utils
 class perf(profiler.profiler):
     version = 1
 
-    def initialize(self, events="cycles,instructions"):
-        self.events = events
+    def initialize(self, events=["cycles","instructions"]):
+        if type(events) == str:
+            self.events = [events]

[lmr, 2011/04/08 00:36:46]

If we are going to support the old way of passing events, one would pass a
string such as:

"cycles,instructions"

So in case it is a string, better split it using commas as a separator. I am
assuming the idea here is to support the old interface, right?

+        else:
+            self.events = events
         self.perf_bin = os_dep.command('perf')
         perf_help = utils.run('%s report help' % self.perf_bin,
                               ignore_status=True).stderr
@@ -31,8 +34,10 @@ class perf(profiler.profiler):
 
     def start(self, test):
         self.logfile = os.path.join(test.profdir, "perf")
-        cmd = ("%s record -a -o %s -e %s" %
-               (self.perf_bin, self.logfile, self.events))
+        cmd = ("%s record -a -o %s" %
+               (self.perf_bin, self.logfile))
+        for event in self.events:
+            cmd += " -e %s" % event
         self._process = subprocess.Popen(cmd, shell=True,
                                          stderr=subprocess.STDOUT)