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authorMaarten Lankhorst <maarten.lankhorst@canonical.com>2013-06-20 13:31:30 +0200
committerIngo Molnar <mingo@kernel.org>2013-06-26 12:10:57 +0200
commit2fe3d4b149ccebbb384062fbbe6634439f2bf120 (patch)
treecc868c534a58bc75f8704d11d9a845a50fe85c17 /lib/locking-selftest.c
parent1de994452f44005e4b1f5c6c77eae4a26f86d484 (diff)
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mutex: Add more tests to lib/locking-selftest.c
None of the ww_mutex codepaths should be taken in the 'normal' mutex calls. The easiest way to verify this is by using the normal mutex calls, and making sure o.ctx is unmodified. Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: dri-devel@lists.freedesktop.org Cc: linaro-mm-sig@lists.linaro.org Cc: robclark@gmail.com Cc: rostedt@goodmis.org Cc: daniel@ffwll.ch Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20130620113130.4001.45423.stgit@patser Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'lib/locking-selftest.c')
-rw-r--r--lib/locking-selftest.c62
1 files changed, 62 insertions, 0 deletions
diff --git a/lib/locking-selftest.c b/lib/locking-selftest.c
index 996226224bcf..37faefdbb678 100644
--- a/lib/locking-selftest.c
+++ b/lib/locking-selftest.c
@@ -1162,6 +1162,67 @@ static void ww_test_fail_acquire(void)
#endif
}
+static void ww_test_normal(void)
+{
+ int ret;
+
+ WWAI(&t);
+
+ /*
+ * None of the ww_mutex codepaths should be taken in the 'normal'
+ * mutex calls. The easiest way to verify this is by using the
+ * normal mutex calls, and making sure o.ctx is unmodified.
+ */
+
+ /* mutex_lock (and indirectly, mutex_lock_nested) */
+ o.ctx = (void *)~0UL;
+ mutex_lock(&o.base);
+ mutex_unlock(&o.base);
+ WARN_ON(o.ctx != (void *)~0UL);
+
+ /* mutex_lock_interruptible (and *_nested) */
+ o.ctx = (void *)~0UL;
+ ret = mutex_lock_interruptible(&o.base);
+ if (!ret)
+ mutex_unlock(&o.base);
+ else
+ WARN_ON(1);
+ WARN_ON(o.ctx != (void *)~0UL);
+
+ /* mutex_lock_killable (and *_nested) */
+ o.ctx = (void *)~0UL;
+ ret = mutex_lock_killable(&o.base);
+ if (!ret)
+ mutex_unlock(&o.base);
+ else
+ WARN_ON(1);
+ WARN_ON(o.ctx != (void *)~0UL);
+
+ /* trylock, succeeding */
+ o.ctx = (void *)~0UL;
+ ret = mutex_trylock(&o.base);
+ WARN_ON(!ret);
+ if (ret)
+ mutex_unlock(&o.base);
+ else
+ WARN_ON(1);
+ WARN_ON(o.ctx != (void *)~0UL);
+
+ /* trylock, failing */
+ o.ctx = (void *)~0UL;
+ mutex_lock(&o.base);
+ ret = mutex_trylock(&o.base);
+ WARN_ON(ret);
+ mutex_unlock(&o.base);
+ WARN_ON(o.ctx != (void *)~0UL);
+
+ /* nest_lock */
+ o.ctx = (void *)~0UL;
+ mutex_lock_nest_lock(&o.base, &t);
+ mutex_unlock(&o.base);
+ WARN_ON(o.ctx != (void *)~0UL);
+}
+
static void ww_test_two_contexts(void)
{
WWAI(&t);
@@ -1415,6 +1476,7 @@ static void ww_tests(void)
print_testname("ww api failures");
dotest(ww_test_fail_acquire, SUCCESS, LOCKTYPE_WW);
+ dotest(ww_test_normal, SUCCESS, LOCKTYPE_WW);
dotest(ww_test_unneeded_slow, FAILURE, LOCKTYPE_WW);
printk("\n");