Re: [9fans] does qlock(2) block all threads on a proc?

["Francisco J Ballesteros" <nemo@lsub.org>]

It's a queueing lock, but otherwise just a lock. Thus, you use it like
lock(), that is

qlock(&l);
...isolated access to your shared data...
qunlock(&l);

The difference wrt lock/unlock is that it does not spin.  If the lock
cannot be set, the
thread is put to sleep in queue waiting for the lock. So, it's better
to use qlock in
general than it is to use lock. (IIRC, lock is used to protect the
data structure of the QLock,
that might give you more insight regarding the difference b/w qlock and lock).

hth



On 8/10/07, david jeannot <djeannot24@gmail.com> wrote:
> Hi,
>
> Does qlock block all threads on a same proc?
> I read lock(2) and thread(2) but I am not sure yet.
>
> Merci beaucoup, david
>