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perf tests: Fix map_groups refcount test

tip:perf/core tip-bot for Arnaldo Carvalho de Melo 1 participant 1 message May 15, 2015 perf events

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Commit-ID:  8b00f46951bed1edd9c5cb9d9adb62d28bbe7623
Gitweb:     http://git.kernel.org/tip/8b00f46951bed1edd9c5cb9d9adb62d28bbe7623
Author:     Arnaldo Carvalho de Melo <[email protected]>
AuthorDate: Mon, 11 May 2015 18:13:14 -0300
Committer:  Arnaldo Carvalho de Melo <[email protected]>
CommitDate: Tue, 12 May 2015 09:59:52 -0300

perf tests: Fix map_groups refcount test

When introducing reference counting for struct thread instances I forgot to remove the synthetic threads from the machine's rbtree so that it then the threads would have just one reference and thus the thread__put() replacing the thread__delete() really turns into a thread__delete() (thread->refcnt == 1 at thread__put() time) and thus drop the thread->mg refcount, as expected by the this test.

Fix it by calling machine__remove_thread() (the counterpart of machine__findnew_thread()) on all the synthetic threads after the checks that involves the rbtree were done.

Before:

  # perf test -v mg
  30: Test thread mg sharing                                 :
  --- start ---
  test child forked, pid 26995
  FAILED tests/thread-mg-share.c:68 wrong refcnt (4 != 3)
  test child finished with -1
  ---- end ----
  Test thread mg sharing: FAILED!
  #

After:

  # perf test mg
  30: Test thread mg sharing: Ok
  #
Fixes b91fc39f4ad7 ("perf machine: Protect the machine->threads with a rwlock")
Cc Adrian Hunter <[email protected]>
Cc Borislav Petkov <[email protected]>
Cc David Ahern <[email protected]>
Cc Don Zickus <[email protected]>
Cc Frederic Weisbecker <[email protected]>
Cc Jiri Olsa <[email protected]>
Cc Namhyung Kim <[email protected]>
Cc Stephane Eranian <[email protected]>
---
 tools/perf/tests/thread-mg-share.c | 17 ++++++++++++-----
 1 file changed, 12 insertions(+), 5 deletions(-)
tools/perf/tests/thread-mg-share.c +12 -5
index 04eccee..c0ed56f 100644
@@ -58,6 +58,18 @@ int test__thread_mg_share(void)
 	other_leader = machine__find_thread(machine, 4, 4);
 	TEST_ASSERT_VAL("failed to find other leader", other_leader);
 
+	/*
+	 * Ok, now that all the rbtree related operations were done,
+	 * lets remove all of them from there so that we can do the
+	 * refcounting tests.
+	 */
+	machine__remove_thread(machine, leader);
+	machine__remove_thread(machine, t1);
+	machine__remove_thread(machine, t2);
+	machine__remove_thread(machine, t3);
+	machine__remove_thread(machine, other);
+	machine__remove_thread(machine, other_leader);
+
 	other_mg = other->mg;
 	TEST_ASSERT_EQUAL("wrong refcnt", other_mg->refcnt, 2);
 
@@ -81,11 +93,6 @@ int test__thread_mg_share(void)
 
 	thread__put(other);
 
-	/*
-	 * Cannot call machine__delete_threads(machine) now,
-	 * because we've already released all the threads.
-	 */
-
 	machines__exit(&machines);
 	return 0;
 }