write() call on kbbl_set blocks for half a second about faustus HOT 2 OPEN

So I did some more research and it seems that the wmi_evaluate_method call takes 0.2 - 0.3 seconds for each RGB call, and it is called twice each time the color is changed. Unfortunately, wmi_evaluate_method is not a part of faustus and I can't go any deeper from here.

Here's my attempt at "printf-debugging" a single kbbl_rgb_write call, take a look at the timestamps:

[29699.923475] faustus: RGB write 1
[29699.923476] faustus: RGB write 2
[29699.923478] faustus: RGB write 3
[29699.923479] faustus: Entering method3
[29699.923480] faustus: WMI eval start
[29700.188824] faustus: WMI eval end
[29700.188825] faustus: Leaving method3
[29700.188826] faustus: RGB write 4
[29700.188826] faustus: Entering method3
[29700.188826] faustus: WMI eval start
[29700.424715] faustus: WMI eval end
[29700.424716] faustus: Leaving method3
[29700.424716] faustus: RGB write 5
[29700.424716] faustus: RGB write 6

All I could find is this: https://elixir.bootlin.com/linux/v3.2.6/source/drivers/platform/x86/wmi.c#L293 but I can't even tinker with it, and I can't find the sources for acpi_evaluate_object either, so I guess I'm stuck.

from faustus.

acpi_evaluate_object is a part of the kernel. I am not skilled enough to make a kernel patch that can be applied automatically to debug ACPI code. I'm asking for help.

from faustus.