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    SubjectRe: [patch 6/8] arm: ns9xxx: Remove private irq flow handler
    Hi Thomas,

    On Wed, Feb 02, 2011 at 09:41:27PM -0000, Thomas Gleixner wrote:
    > handle_prio_irq is almost identical with handle_fasteoi_irq. The
    > subtle differences are
    >
    > 1) The handler checks for IRQ_DISABLED after the device handler has
    > been called. In case it's set it masks the interrupt.
    >
    > 2) When the handler sees IRQ_DISABLED on entry it masks the interupt
    > in the same way as handle_fastoei_irq, but does not set the
    > IRQ_PENDING flag.
    >
    > 3) Instead of gracefully handling a recursive interrupt it crashes the
    > kernel.
    >
    > #1 is just relevant when a device handler calls disable_irq_nosync()
    > and it does not matter whether we mask the interrupt right away or
    > not. We handle lazy masking for disable_irq anyway, so there is no
    > real reason to have this extra mask in place.
    >
    > #2 will prevent the resend of a pending interrupt, which can result in
    > lost interrupts for edge type interrupts. For level type interrupts
    > the resend is a noop in the generic code. According to the
    > datasheet all interrupts are level type, so marking them as such
    > will result in the exact same behaviour as the private
    > handle_prio_irq implementation.
    >
    > #3 is just stupid. Crashing the kernel instead of handling a problem
    > gracefully is just wrong. With the current semantics- all handlers
    > run with interrupts disabled - this is even more wrong.
    >
    > Rename ack to eoi, remove the unused mask_ack, switch to
    > handle_fasteoi_irq and remove the private function.
    >
    > Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
    > Cc: Uwe Kleine-Koenig <u.kleine-koenig@pengutronix.de>
    > Cc: linux-arm-kernel@lists.infradead.org
    I have no access to a ns9xxx machine, but this looks sane.

    Acked-by: Uwe Kleine-Koenig <u.kleine-koenig@pengutronix.de>

    Thanks
    Uwe

    --
    Pengutronix e.K. | Uwe Kleine-König |
    Industrial Linux Solutions | http://www.pengutronix.de/ |
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