Re: [PATCH v5 19/27] irqchip/gic-v3: Remove acknowledge loop

[Marc Zyngier]

On 28/08/18 16:51, Julien Thierry wrote:
> Multiple interrupts pending for a CPU is actually rare. Doing an
> acknowledge loop does not give much better performance or even can
> deteriorate them.
>
> Do not loop when an interrupt has been acknowledged, just return
> from interrupt and wait for another one to be raised.
>
> Tested-by: Daniel Thompson <daniel.thompson@xxxxxxxxxx>
> Signed-off-by: Julien Thierry <julien.thierry@xxxxxxx>
> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
> Cc: Jason Cooper <jason@xxxxxxxxxxxxxx>
> Cc: Marc Zyngier <marc.zyngier@xxxxxxx>
> ---
>   drivers/irqchip/irq-gic-v3.c | 65 +++++++++++++++++++++-----------------------
>   1 file changed, 31 insertions(+), 34 deletions(-)

It would probably be valuable to do the same thing for GICv1/v2, where 
the MMIO access can be even more costly.

In the meantime, I've queued this for 4.20.

Thanks,

	M.
--
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