Re: [PATCH for next v1 1/2] gpio: omap: Replace raw_spin_lock_irqsave with raw_spin_lock in omap_gpio_irq_handler()

From: Arnd Bergmann
Date: Thu Feb 11 2021 - 14:41:03 EST


On Thu, Feb 11, 2021 at 7:25 PM Grygorii Strashko
<grygorii.strashko@xxxxxx> wrote:
> On 08/02/2021 10:56, Luo Jiaxing wrote:
> > There is no need to use API with _irqsave in omap_gpio_irq_handler(),
> > because it already be in a irq-disabled context.
>
> NACK.
> Who said that this is always hard IRQ handler?
> What about RT-kernel or boot with "threadirqs"?

In those cases, the interrupt handler is just a normal thread, so the
preempt_disable() that is implied by raw_spin_lock() is sufficient.

Disabling interrupts inside of an interrupt handler is always incorrect,
the patch looks like a useful cleanup to me, if only for readability.

Arnd