Re: adm1026 driver port for kernel 2.6.10-rc2 [RE-REVISED DRIVER]

[linux-os]

On Mon, 22 Nov 2004, Arjan van de Ven wrote:

> > > this locking construct is rahter awkward; is it possible to refactor the
> > > code such that you can down and up in the same function ?
> >
> > Yes, at the cost of some minor code duplication or the introduction of
> > another variable.  Is that preferable?  Is holding the lock across function
> > calls a Bad Idea?
>
> holding lock across function calls isn't, unlocking in another function
> than you take the lock is.
> For one it makes auditing the code a lot harder.

Also, code like:

	down(&mylock);
	do_something();
        if(fail) {
            up(&mylock);
            return retval;
        }

... is prone to errors where a lock never gets released on some
corner cases. It's often better to "goto" a common exit point where
the lock is released.


Cheers,
Dick Johnson
Penguin : Linux version 2.6.9 on an i686 machine (5537.79 BogoMips).
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