On Fri, Nov 23, 2018 at 1:43 PM Michal Hocko <mhocko@xxxxxxxxxx> wrote: > On Fri 23-11-18 13:30:57, Daniel Vetter wrote: > > On Fri, Nov 23, 2018 at 12:15:57PM +0100, Michal Hocko wrote: > > > On Thu 22-11-18 17:51:04, Daniel Vetter wrote: > > > > Just a bit of paranoia, since if we start pushing this deep into > > > > callchains it's hard to spot all places where an mmu notifier > > > > implementation might fail when it's not allowed to. > > > > > > What does WARN give you more than the existing pr_info? Is really > > > backtrace that interesting? > > > > Automated tools have to ignore everything at info level (there's too much > > of that). I guess I could do something like > > > > if (blockable) > > pr_warn(...) > > else > > pr_info(...) > > > > WARN() is simply my goto tool for getting something at warning level > > dumped into dmesg. But I think the pr_warn with the callback function > > should be enough indeed. > > I wouldn't mind s@pr_info@pr_warn@ Well that's too much, because then it would misfire in the oom testcase, where failing is ok (desireble even, we want to avoid blocking after all). So needs to be a switch (or else we need to filter it in results, and that's a bit a maintenance headache from a CI pov). -Danile > > If you wonder where all the info level stuff happens that we have to > > ignore: suspend/resume is a primary culprit (fairly important for > > gfx/desktops), but there's a bunch of other places. Even if we ignore > > everything at info and below we still need filters because some drivers > > are a bit too trigger-happy (i915 definitely included I guess, so everyone > > contributes to this problem). > > Thanks for the clarification. > -- > Michal Hocko > SUSE Labs -- Daniel Vetter Software Engineer, Intel Corporation +41 (0) 79 365 57 48 - http://blog.ffwll.ch
