On Wed, Jun 29, 2022 at 5:30 PM Jason A. Donenfeld Jason@zx2c4.com wrote:
Hey again,
On Thu, Jun 30, 2022 at 2:24 AM Jason A. Donenfeld Jason@zx2c4.com wrote:
Introduce a simple CONFIG_PM_CONTINUOUS_AUTOSLEEPING Kconfig thing with lots of discouraging help text.
Go with the /sys/power tunable and bikeshed the naming of that a bit to get it to something that reflects this better, and document it as being undesirable except for Android phones.
One other quick thought, which I had mentioned earlier to Kalesh:
- Make the semantics a process holding open a file descriptor, rather than writing 0/1 into a file. It'd be called /sys/power/ userspace_autosleep_ctrl, or something, and it'd enable this behavior while it's opened. And maybe down the line somebody will want to add ioctls to it for a different purpose. This way it's less of a tunable and more of an indication that there's a userspace app doing/controlling something.
This idea (3) may be a lot of added complexity for basically nothing, but it might fit the usage semantics concerns a bit better than (2). But anyway, just an idea. Any one of those three are fine with me.
Two concerns John raised: 1) Adding new ABI we need to maintain 2) Having unclear config options
Another idea, I think, is to add the Kconfig option as CONFIG_SUSPEND_SKIP_RNG_RESEED? Similar to existing CONFIG_SUSPEND_SKIP_SYNC and I think it would address those concerns.
--Kalesh
Jason