cyclictest: Use a tempfile buffer for cyclictest's stdout data

Using subprocess.PIPE doesn't allow cyclictest to completely exit
before the pipe is emptied.  When using cyclictest with --breaktrace,
rteval will then not see that cyclictest isn't measuring and will
wait until the complete measurement duration has completed instead
of doing an earlier exit.

By using tempfile.SpooledTemporaryFile(), subprocess have a valid
file descriptor it can write the stdout data too.  This makes also
cyclictest exit instantly when it needs to.

Signed-off-by: David Sommerseth <davids@redhat.com>

1 files changed, 13 insertions, 5 deletions

diff --git a/rteval/modules/measurement/cyclictest.py b/rteval/modules/measurement/cyclictest.py
index d0c7ed8..340f7ef 100644
--- a/rteval/modules/measurement/cyclictest.py
+++ b/rteval/modules/measurement/cyclictest.py
@@ -25,7 +25,7 @@
 #   are deemed to be part of the source code.
 #
 
-import os, sys, subprocess, signal, libxml2, shutil
+import os, sys, subprocess, signal, libxml2, shutil, tempfile, time
 from rteval.Log import Log
 from rteval.modules import rtevalModulePrototype
 
@@ -202,6 +202,7 @@ class Cyclictest(rtevalModulePrototype):
         self.__cyclicdata['system'].description = ("(%d cores) " % self.__numcores) + self.__cyclicdata['0'].description
         self._log(Log.DEBUG, "system has %d cpu cores" % self.__numcores)
         self.__started = False
+        self.__cyclicoutput = None
 
 
     def __getmode(self):
@@ -238,7 +239,7 @@ class Cyclictest(rtevalModulePrototype):
 
         self.__cmd = ['cyclictest',
                       self.__interval,
-                      '-qm',
+                      '-qmu',
                       '-h %d' % self.__buckets,
                       "-p%d" % int(self.__priority),
                       self.__getmode(),
@@ -250,6 +251,9 @@ class Cyclictest(rtevalModulePrototype):
         if self.__cfg.has_key('breaktrace') and self.__cfg.breaktrace:
             self.__cmd.append("-b%d" % int(self.__cfg.breaktrace))
 
+        # Buffer for cyclictest data written to stdout
+        self.__cyclicoutput = tempfile.SpooledTemporaryFile(mode='rw+b')
+
 
     def _WorkloadTask(self):
         if self.__started:
@@ -268,8 +272,9 @@ class Cyclictest(rtevalModulePrototype):
             fp.flush()
             fp.close()
 
+        self.__cyclicoutput.seek(0)
         self.__cyclicprocess = subprocess.Popen(self.__cmd,
-                                                stdout=subprocess.PIPE,
+                                                stdout=self.__cyclicoutput,
                                                 stderr=self.__nullfp,
                                                 stdin=self.__nullfp)
         self.__started = True
@@ -283,11 +288,14 @@ class Cyclictest(rtevalModulePrototype):
 
 
     def _WorkloadCleanup(self):
-        if self.__cyclicprocess.poll() == None:
+        while self.__cyclicprocess.poll() == None:
+            self._log(Log.DEBUG, "Sending SIGINT")
             os.kill(self.__cyclicprocess.pid, signal.SIGINT)
+            time.sleep(2)
 
         # now parse the histogram output
-        for line in self.__cyclicprocess.stdout:
+        self.__cyclicoutput.seek(0)
+        for line in self.__cyclicoutput:
             if line.startswith('#'): continue
             vals = line.split()
             index = int(vals[0])