[PATCH] ww-mutex: clarify help text for DEBUG_WW_MUTEX_SLOWPATH

Rob Clark robdclark at gmail.com
Wed Aug 27 08:19:26 PDT 2014

We really don't want distro's enabling this in their kernels.  Try and
make that more clear.

Signed-off-by: Rob Clark <robdclark at gmail.com>
 lib/Kconfig.debug | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 07c2832..1b233fc 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -892,6 +892,10 @@ config DEBUG_WW_MUTEX_SLOWPATH
 	 the full mutex checks enabled with (CONFIG_PROVE_LOCKING) this
 	 will test all possible w/w mutex interface abuse with the
 	 exception of simply not acquiring all the required locks.
+	 Note that this feature can introduce significant overhead, so
+	 it really should not be enabled in a production or distro kernel,
+	 even a debug kernel.  If you are a driver writer, enable it.  If
+	 you are a distro, do not.
 	bool "Lock debugging: detect incorrect freeing of live locks"

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