Re: [PATCH] arm: perf: Directly handle SMP platforms with one SPI

[Linus Walleij]

On Fri, Nov 21, 2014 at 3:53 PM, Daniel Thompson
<daniel.thompson@xxxxxxxxxx> wrote:

> Some ARM platforms mux the PMU interrupt of every core into a single
> SPI. On such platforms if the PMU of any core except 0 raises an interrupt
> then it cannot be serviced and eventually, if you are lucky, the spurious
> irq detection might forcefully disable the interrupt.
>
> On these SoCs it is not possible to determine which core raised the
> interrupt so workaround this issue by queuing irqwork on the other
> cores whenever the primary interrupt handler is unable to service the
> interrupt.
>
> The u8500 platform has an alternative workaround that dynamically alters
> the affinity of the PMU interrupt. This workaround logic is no longer
> required so the original code is removed as is the hook it relied upon.
>
> Tested on imx6q (which has fours cores/PMUs all muxed to a single SPI).
>
> Signed-off-by: Daniel Thompson <daniel.thompson@xxxxxxxxxx>

After som pain I managed to compile and test this with perf.
Works like a charm.

Tested-by: Linus Walleij <linus.walleij@xxxxxxxxxx>

Yours,
Linus Walleij
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