On Wed, 26 Sep 2018 08:36:47 -0700 Dave Hansen <dave.hansen@xxxxxxxxx> wrote: > On 09/26/2018 12:38 AM, Michal Hocko wrote: > > Why cannot you simply go with [no]vm_page_poison[=on/off]? > > I was trying to look to the future a bit, if we end up with five or six > more other options we want to allow folks to enable/disable. I don't > want to end up in a situation where we have a bunch of different knobs > to turn all this stuff off at runtime. > > I'd really like to have one stop shopping so that folks who have a > system that's behaving well and don't need any debugging can get some of > their performance back. > > But, the *primary* thing we want here is a nice, quick way to turn as > much debugging off as we can. A nice-to-have is a future-proof, > slub-style option that will centralize things. Yup. DEBUG_VM just covers too much stuff nowadays. A general way to make these thing more fine-grained and without requiring a rebuild would be great. And I expect that quite a few of the debug features could be enabled/disabled after bootup as well, so a /proc knob is probably in our future. Any infrastructure which is added to support a new kernel-command-line option should be designed with that in mind.
