Messages in this thread | | | Date | Wed, 25 Apr 2007 08:58:53 -0700 (PDT) | From | Christoph Lameter <> | Subject | Re: [PATCH -mm] slub: update cpu after new_slab() |
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On Wed, 25 Apr 2007, Hugh Dickins wrote:
> > Right. local_irq_save does not switch off preemption as I thought. > > Strange comment. Preemption is not possible while IRQs are disabled, > but new_slab() rightly reenables them within itself in the __GFP_WAIT > case, since it's going off to do a page allocation and may need to wait.
Yes I expected local_irq_save to increase the preempt count and then local_irq_enable to simply enable interrupts without affecting the preempt count. Thus the process should stay on the same processor.
Never thought it would be possible to move to a different processor in mid flight. - 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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