Re: [PATCH] udev enhancements to use kernel event queue

Davide Libenzi
2003-06-12T23:34:09Z

On Thu, 12 Jun 2003, Patrick Mochel wrote:

>
> > > + spin_lock(&sequence_lock);
> > > + seq = sequence_num++;
> > > + spin_unlock(&sequence_lock);
> > > +
> > > + envp [i++] = scratch;
> > > + scratch += sprintf(scratch, "SEQNUM=%ld", seq) + 1;
> >
> > Nice thinking. It is a shame we need a lock for this, but we don't have
> > an atomic_inc_and_return().
>
> Those were my sentiments exactly:
>
> 16:21 * mochel searches for atomic_inc_and_read() :)
>
> It seems like the following should work. Would someone mind commenting on
> it?

It does not Pat, look at the generated asm.

- Davide