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

Rafael J. Wysocki
2023-12-15T11:34:31Z

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.

Thanks!