Messages in this thread | | | Date | Tue, 4 Jan 2011 15:03:55 +0100 | From | Pavel Machek <> | Subject | Re: [PATCH v0] add nano semaphore in kernel |
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Hi!
> +/* > + * nano_semaphore_down - acquire the nano semaphore > + * @s: the nano semaphore to be acquired > + * @nano_secs: the nano seconds to wait if necessary, > + * could be zero if want to wait as long as possible. > + * > + * Returns >0 if acquired successfully, <=0 otherwise. > + * > + * Note unlike down() in semaphore, nano_semaphore_down is not looping until > + * the nano semaphore is hold, but simply reports the result. And the callers > + * could, if they like, loop in simple manner, for instance, > + * while (1 != nano_semaphore_down(s, 800)); > + * do_home_work(); > + * nano_semaphore_up(s);
But thats spinlock, not semaphore, right?
Also, your example does not use the API right -- according to description, 42 is correct 'semaphore acquired' reply...
-- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
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