From: Luca Coelho <luciano.coelho@xxxxxxxxx> 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 <luciano.coelho@xxxxxxxxx> --- 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 <linux/spinlock.h> +#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
