Subj : Re: Challenge: Multithreading & Synchronization
To   : comp.programming.threads
From : David Schwartz
Date : Fri May 20 2005 06:01 pm


"Uenal Mutlu" <520001085531-0001@t-online.de> wrote in message 
news:d6lskp$r71$03$1@news.t-online.com...

>> See also this DOC of Micro$oft:
>> http://www.microsoft.com/whdc/driver/kernel/locks.mspx
>> (http://download.microsoft.com/download/e/b/a/eba1050f-a31d-436b-9281-92cdfeae4b45/Locks.doc)
>
> Citation from the above DOC:
>
> "InterlockedXxx Routines
> The InterlockedXxx routines perform common arithmetic and logical 
> operations atomically,
> ensuring correct results on SMP systems. Whenever possible, drivers should 
> use these routines.
> Most of them are native processor instructions and therefore do not 
> require a lock.
> The InterlockedXxx routines can be used with pageable data. They are 
> usually
> implemented inline by the compiler and can be called at any IRQL."

    Then you've reinvented a less-efficient version of the spinlock. 
Congratulations. (Hint: What is the InterlockedXxx routine to check the 
value of a something without unsharing it?)

    DS

.