On Wed, 2014-06-04 at 23:54 +0200, Thomas Gleixner wrote: > On Wed, 4 Jun 2014, Jason Low wrote: > > On Wed, 2014-06-04 at 21:43 +0200, Peter Zijlstra wrote: > > > > /* > > > > * A negative mutex count indicates that waiters are sleeping waiting > > > > for the > > > > - * mutex. > > > > + * mutex, and a count of one indicates the mutex is unlocked. > > > > */ > > > > #define MUTEX_SHOW_NO_WAITER(mutex) > > > > (atomic_read(&(mutex)->count) >= 0) > > > > +#define MUTEX_IS_UNLOCKED(mutex) > > > > (atomic_read(&(mutex)->count) == 1) > > > > > > So I recently saw that MUTEX_SHOW_NO_WAITER thing and cried a little; > > > and now you're adding more of that same nonsense. > > > > > > Please make them inline functions, also can we rename the SHOW_NO_WAITER > > > thing, because its not at all clear to me wtf it does; should it be > > > called: mutex_no_waiters() or somesuch? > > > > Okay, I can make them inline functions. I mainly added the macro to keep > > it consistent with the MUTEX_SHOW_NO_WAITER() check, but we can surely > > Consistency with a digusting and nonsensical macro is not really a > good argument.
I agree :) > > make this more clear. mutex_no_waiters() sounds fine, or perhaps > > something like mutex_has_no_waiters()? > > Uuurg. So we end up with > > if (!mutex_has_no_waiters(m)) > > if we check for waiters? > > Can we please go with the most intuitive thing: > > mutex_has_waiters() > > and have the callsites prepend the '!' in case they want to check > there is no waiter? Yes, !mutex_has_waiters() sounds like the better option to check for no waiters. Same with using the already provided mutex_is_locked() function. > For heavens sake, we do not name macros/inlines in a way which fits > the intended use case. We name them so they make sense. > > Your change log blurbs about readability. I have no idea what your > understandig of readability is, but neither MUTEX_SHOW_NO_WAITERS nor > mutex_has_no_waiters qualify for me. Ditto for MUTEX_IS_UNLOCKED. > > Care to look at the other lock implementations: > > rt_mutex_has_waiters() > spin_is_locked() > .... > > Why would it make sense to come up with reverse conventions for mutex? > > Thanks, > > tglx Thanks, Jason -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
