Re: IDE spin_lock bug

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Jens Axboe wrote:
>
> Hi,
>
> After browsing through Rusty's locking guide today, it occured to
> me that IDE violates the _irqsave rule of passing flags
> to a different function which does the restoring. The easy solution
> is to inline ide_spin_wait_hwgroup.

Have you checked the asm to make sure the function is inlined?
Typically the rule is you must make it 'static inline' to better ensure
inlining.

Stepping back a bit, is this function ever called with interrupts
disabled and such? If not, you can use spin_lock_irq in certain
[carefully considered] cases. That eliminates worrying about 'flags'
completely and is a bit faster.

        Jeff

-- 
Jeff Garzik              | Nothing cures insomnia like the
Building 1024            | realization that it's time to get up.
MandrakeSoft, Inc.       |        -- random fortune
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