Re: [PATCH v1 0/3] ACPI: OSL/EC: Use spin locks without disabling interrupts

Rafael J. Wysocki
2023-12-28T13:19:04Z

On Fri, Dec 15, 2023 at 12:34 PM Rafael J. Wysocki <rjw@rjwysocki.net> wrote:
>
> Hi Everyone,
>
> After
>
> https://patchwork.kernel.org/project/linux-acpi/patch/5745568.DvuYhMxLoT@kreacher/
>
> the SCI interrupt handler is threaded, so ACPICA spin locks can be used without
> disabling interrupts, because they cannot be acquired from a hardirq handler
> running on the same CPU as any code already holding the spin lock. This patch
> [1/3] removes disabling interrupts from acpi_os_acquire_lock() and updates
> acpi_os_release_lock() accordingly.
>
> Patch [2/2] uses the observation that if acpi_handle_interrupt() can run
> in a threaded interrupt handler in the GPE case, it can also run in a threaded
> interrupt handler in the dedicated IRQ case, so it makes the EC driver use a
> threaded handler for the dedicated EC interrupt.
>
> Patch [3/3], in analogy with patch [1/3], uses the observation that after patch
> [2/2] all of the EC code runs in thread context, so it need not disable
> interrupts on the local CPU before acquiring a spin lock, so the EC driver is
> updated to operate its spin lock without disabling interrupts.

I don't see any objections to these patches, so queuing them up for 6.8.

Thanks!