From: Laurence Tratt <laurie@tratt.net>
Subject: Re: video(4): replace selinfo with klist and make `video_filtops' mp-safe
To: tech@openbsd.org
Date: Sat, 14 Dec 2024 16:12:54 +0000

On Sat, Dec 14, 2024 at 07:07:09AM +0300, Vitaliy Makkoveev wrote:

Hello Vitaliy,

> Since {,u}video(4) are no more orphaned, I like to remind about my old
> diff which replaces legacy selinfo data with klist. This time selinfo is
> just a wrapper around klist, but protected with kernel lock. This diff
> introduces `sc_mtx' mutex(9) to protect `sc_frames_ready' and klist
> data.

This not only works fine with a "MACROSILICON USB Video" but noticeably
lowers the `spin` percentage I see in `top` (from ~1.5% to ~0.5%) when
using a webcam with ffplay -- thanks!


Laurie