Re: FUSYN and RT

[john cooper <john.cooper@timesys.com>]

Sven Dietrich wrote:
>>>	/** A fuqueue, a prioritized wait queue usable from
>>
>>kernel space. */
>>
>>>	struct fuqueue {
>>>	        spinlock_t lock;        
>>>	        struct plist wlist;
>>>	        struct fuqueue_ops *ops;
>>>	};
>>>
>>
>>Would the above spinlock_t be a raw_spinlock_t? This goes
>>back to my first question. I'm not sure how familiar you are 
>>with Ingo's work, but he has turned all spinlocks into 
>>mutexes, and when you really need an original spinlock, you 
>>declare it with raw_spinlock_t.  
>>
> 
> 
> This one probably should be a raw_spinlock. 
> This lock is only held to protect access to the queues.
> Since the queues are already priority ordered, there is
> little benefit to ordering -the order of insertion-
> in case of contention on a queue, compared with the complexity.

The choice of lock type should derive from both the calling
context and the length of time the lock is expected to be held.

-john


-- 
john.cooper@timesys.com