Re: no DRQ after issuing WRITE was Re: 2.4.23-uv3 patch set released

From: Linus Torvalds
Date: Tue Dec 30 2003 - 18:01:45 EST




On Tue, 30 Dec 2003, Rob Love wrote:
>
> Anyhow, if interrupts are disabled, preemption should be disabled (we
> check for that condition in both preempt_schedule() and
> return_from_intr).

Interrupts are _not_ disabled here, very much on purpose. If they were,
then "jiffies" wouldn't update, and the timeouts wouldn't work.

This is what that _stupid_ "local_irq_set()" function does: it saves the
old irq masking state, and then it enables it.

The whole concept doesn't make any sense. If you enable interrupts, there
is little point in saving the callers irq mask, since it already got
deflated.

Linus
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