Messages in this thread | | | Date | Tue, 13 Aug 2002 11:09:57 -0700 | From | Andrew Morton <> | Subject | Re: [patch 2/21] reduced locking in buffer.c |
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Christoph Hellwig wrote: > > On Tue, Aug 13, 2002 at 10:53:59AM -0700, Andrew Morton wrote: > > I have discussed it with David - he said it's OK in 2.5, but > > not in 2.4, and he has eyeballed the diff. > > > > However there's another thing to think about: > > > > local_irq_disable(); > > atomic_inc(); > > > > If the architecture implements atomic_inc with spinlocks, this will > > schedule with interrupts off with CONFIG_PREEMPT=y, I expect. > > > > I can fix that with a preempt_disable() in there, but ick. > > Is there a reason you can't just use brlocks?
I didn't use brlocks in the initial code because I wanted the lock in the same cacheline as the data it's locking.
And this code removes the locking altogether.
I suspect the lock traffic is in the noise compared with all the get_bh, brelse, set_bit and clear_bit operations but it's a start. We don't have a tool to measure those other things ;) - 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/
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