From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from paleale.coelho.fi ([176.9.41.70]:50992 "EHLO farmhouse.coelho.fi" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727986AbeITRL4 (ORCPT ); Thu, 20 Sep 2018 13:11:56 -0400 From: Luca Coelho To: backports@vger.kernel.org Cc: Luca Coelho Date: Thu, 20 Sep 2018 14:28:36 +0300 Message-Id: <20180920112842.27198-9-luca@coelho.fi> (sfid-20180920_132857_084859_C2AFB345) In-Reply-To: <20180920112842.27198-1-luca@coelho.fi> References: <20180920112842.27198-1-luca@coelho.fi> Subject: [PATCH 08/14] backport: prevent unused subclass variable warning in < 3.18 Sender: backports-owner@vger.kernel.org List-ID: From: Luca Coelho In kernels earlier than 3.18, the raw_spin_lock defininition when CONFIG_DEBUG_LOCK_ALLOC is not enabled, was dropping one of the parameters, which caused a few "unused variable" warnings at places where this argument was only used in the call to raw_spin_lock_nested(). Take the latest definition which evaluates the argument to avoid compiler warnings. Signed-off-by: Luca Coelho --- backport/backport-include/linux/spinlock.h | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/backport/backport-include/linux/spinlock.h b/backport/backport-include/linux/spinlock.h index 07daa358e25d..a46f6e33b241 100644 --- a/backport/backport-include/linux/spinlock.h +++ b/backport/backport-include/linux/spinlock.h @@ -2,6 +2,21 @@ #define __BACKPORT_SPINLOCK_H #include_next +#if LINUX_VERSION_IS_LESS(3,18,0) +#ifndef CONFIG_DEBUG_LOCK_ALLOC +#undef raw_spin_lock_nested +/* + * Always evaluate the 'subclass' argument to avoid that the compiler + * warns about set-but-not-used variables when building with + * CONFIG_DEBUG_LOCK_ALLOC=n and with W=1. + */ +# define raw_spin_lock_nested(lock, subclass) \ + _raw_spin_lock(((void)(subclass), (lock))) +# define raw_spin_lock_nest_lock(lock, nest_lock) _raw_spin_lock(lock) +#endif +#endif /* LINUX_VERSION_IS_LESS(3,18,0) */ + + #if LINUX_VERSION_IS_LESS(4,16,0) int alloc_bucket_spinlocks(spinlock_t **locks, unsigned int *lock_mask, size_t max_size, unsigned int cpu_mult, -- 2.18.0 -- To unsubscribe from this list: send the line "unsubscribe backports" in