add Valgrind suppression to ignore userspace-rcu leak

smoke_test

@@ -20,7 +20,7 @@
 
 set -e
 
-PYTEST=pytest-3
+PYTEST="${PYTEST:-pytest-3}"
 spam=$(tempfile)
 unset BCACHEFS_FUSE BCACHEFS_TEST_USE_VALGRIND D
 

tests/util.py

@@ -49,6 +49,8 @@ def run(cmd, *args, valgrind=False, check=False):
         vout = tempfile.NamedTemporaryFile()
         vcmd = ['valgrind',
                '--leak-check=full',
+               '--gen-suppressions=all',
+               '--suppressions=valgrind-suppressions.txt',
                '--log-file={}'.format(vout.name)]
         cmds = vcmd + cmds
 
@@ -161,6 +163,8 @@ class BFuse:
             vlog = tempfile.NamedTemporaryFile()
             cmd += [ 'valgrind',
                      '--leak-check=full',
+                     '--gen-suppressions=all',
+                     '--suppressions=valgrind-suppressions.txt',
                      '--log-file={}'.format(vlog.name) ]
 
         cmd += [ BCH_PATH,

tests/valgrind-suppressions.txt

@@ -0,0 +1,8 @@
+{
+   <insert_a_suppression_name_here>
+   Memcheck:Leak
+   match-leak-kinds: possible,definite
+   ...
+   fun:get_default_call_rcu_data_memb
+   fun:call_rcu_memb
+}