On Tue, 22 Jul 2014, Andrew Morton wrote: > > Evaluating a macro argument only if certain configuration options > > have been selected is confusing and error-prone. Hence always > > evaluate the second argument of spin_lock_nested() and > > spin_lock_nest_lock(). > > > > An intentional side effect of this patch is that it avoids that > > the following warning is reported for netif_addr_lock_nested() > > when building with CONFIG_DEBUG_LOCK_ALLOC=n and with W=1: > > > > ... > > > > --- a/include/linux/spinlock.h > > +++ b/include/linux/spinlock.h > > @@ -197,8 +197,10 @@ static inline void do_raw_spin_unlock(raw_spinlock_t > > *lock) __releases(lock) > > _raw_spin_lock_nest_lock(lock, &(nest_lock)->dep_map); \ > > } while (0) > > #else > > -# define raw_spin_lock_nested(lock, subclass) > > _raw_spin_lock(lock) > > -# define raw_spin_lock_nest_lock(lock, nest_lock) _raw_spin_lock(lock) > > +# define raw_spin_lock_nested(lock, subclass) \ > > + ((void)(subclass), _raw_spin_lock(lock)) > > +# define raw_spin_lock_nest_lock(lock, nest_lock) \ > > + ((void)(nest_lock), _raw_spin_lock(lock)) > > #endif > > > > Did you try converting these to static inline functions? That should > squish the warning and makes the code nicer instead of nastier... >
Not sure how that would be done since _raw_spin_lock isn't declared in this scope. Taking a second look, however, I think the patch doesn't need to modify raw_spin_lock_nest_lock() for the problem being reported and evaluating the parameter of type struct lockdep_map * probably is meaningless. Bart, is it possible to just get away with the raw_spin_lock_nested() change? -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
