In message <Pine.LNX.4.33.0110120948540.31692-100000@penguin.transmeta.com> you
write:
> Yes. With maybe
>
> non_preempt()
> ..
> preempt()
>
> around it for the pre-emption patches.
Sure, if they want pre-emption on SMP. Of course, then they'll want
priority inheritence.
> However, you also need to make your free _free_ be aware of the count.
> Which means that the current RCU patch is really unusable for this. You
> need to have the "count" always in a generic place (put it with the hash),
> and your schedule-time free needs to do
>
> if (atomic_read(&count))
> skip_this_do_it_next_time
WTF? I'll spell it out for you again:
static inline void foo_put(struct foo *foo)
{
if (atomic_dec_and_test(foo->use))
kfree(foo);
}
Write side normal:
lock
unhash(foo)
unlock
foo_put(foo)
Write side RCU:
lock
unhash(foo)
unlock
rcu_call(foo_put, foo);
/* ie. call foo_put(foo) "later". */
That's all. Really.
> Do that, and the RCU patches may start looking usable for the real world.
I know you're under strain, but think harder please.
Rusty.
-- Premature optmztion is rt of all evl. --DK - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
This archive was generated by hypermail 2b29 : Mon Oct 15 2001 - 21:00:48 EST