>Look at the implementation of "cli()" - when called from within a hardware
>interrupt, it will do something else than what you think it's doing, and
>"synchronize_irq()" will basically be a no-op.
Yes that was exactly my point.
>Bogus. It won't really harm (see no-op above), but it certainly doesn't
>help either.
Yes.
>Again, that one looks like it shouldn't actually harm anything, but
>doesn't help.
Infact. It was my idea too.
>For the REAL uses, look at some of the SCSI and sound drivers:
>
> outb(~0, s->ioenh + SV_CODEC_INTMASK); /* disable ints */
> synchronize_irq();
Thanks for the testcase!
>where the point of synchronize_irq() is to just wait for current
>interrupts to exit, because we just asked the card to not send any new
>ones.
Fine.
>That's still not necessarily a good practice (see my previous email about
>asynchroneity wrt CPU/device models), but at least it's not a silly no-op
>like the ones you looked at.
Agreed ;).
Andrea Arcangeli
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