Re: [patch 05/15] Generic Mutex Subsystem, mutex-core.patch

[Steven Rostedt <rostedt@goodmis.org>]

On Mon, 2005-12-19 at 02:37 +0100, Ingo Molnar wrote:
> +static inline void __mutex_unlock_nonatomic(struct mutex *lock
> __IP_DECL__)
> +{
> +       struct thread_info *ti = current_thread_info();
> +       unsigned long flags;
> +
> +       debug_lock_irqsave(&debug_lock, flags, ti);
> +       spin_lock(&lock->wait_lock);
> +
> +#ifdef CONFIG_DEBUG_MUTEXESS
> +       DEBUG_WARN_ON(lock->magic != lock);
> +       DEBUG_WARN_ON(!lock->wait_list.prev && !lock->wait_list.next);
> +       DEBUG_WARN_ON(lock->owner != ti);
> +       if (debug_on) {
> +               DEBUG_WARN_ON(list_empty(&lock->held_list));
> +               list_del_init(&lock->held_list);
> +       }
> +#endif
> +

The unlikely below is only for the non MUTEX_LOCKLESS_FASTPATH case.
Maybe have a define for the unlikely?

#ifdef MUTEX_LOCKLESS_FASTPATH
#  define UNLIKELY_SLOW(x) x
#else
#  define UNLIKELY_SLOW(x) unlikely(x)
#endif

-- Steve


> +       if (unlikely(!list_empty(&lock->wait_list)))
> +               __mutex_wakeup_waiter(lock __IP__);
> +#ifdef CONFIG_DEBUG_MUTEXESS
> +       lock->owner = NULL;
> +#endif