Messages in this thread | | | Date | Wed, 17 Dec 2014 13:47:30 +0100 | From | Frederic Weisbecker <> | Subject | Re: [nohz] 2a16fc93d2c: kernel lockup on idle injection |
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On Wed, Dec 17, 2014 at 10:11:58AM +0100, Thomas Gleixner wrote: > On Wed, 17 Dec 2014, Frederic Weisbecker wrote: > > On Tue, Dec 16, 2014 at 10:21:27PM +0100, Thomas Gleixner wrote: > > > So instead of evaluating the whole nonsense a gazillion times in a row > > > and firing pointless self ipis why are you not looking at the obvious > > > solution of sane state change tracking? > > > > Because I had to do it wrong first before somebody like you with a fresh mind > > comes, look at the whole picture and propose a rethink :-) > > Point taken. > > > > I told all of you from the very beginning that remote accounting > > > is a key mechanism for this, but you keep insisting on hacking > > > around it. > > > > I don't, and I think everybody has understood we are not going to accept > > hacks to solve the 1hz issue. > > You wish. > > > I'm pretty sure you know what this is about to maintain a project with a > > (variably) cruel lack of manpower ;-) > > Oh yes! :( > > > Moreover I'm not the kind of kernel developer who ignores reviews (whether pre or > > post merge). > > I know that. > > > So, no point in threatening a dependency to BROKEN or ripping out except perhaps to > > push me out to other projects with more thankful managers. > > This was not directed to you, really. > > This was directed at the folks who randomly "fix" that code by voodoo > bandaids instead of analyzing the root causes in the first > place. You're the least one to blame for that.
Well I was about to propose a bad fix for powerclamp and I sometimes take overengineering directions. I'm still to blame for several things 8-)
Sorry I got too touchy :-)
Anyway, I'll give a try to your proposition. Somehow I have always felt that something was wrong with this tick_nohz_can_stop_tick() called all over the place, that plus the IPI that's often near the scheduler IPI.
I'm pretty sure this is going to help fixing some overhead issues I got reported.
Thanks a lot!
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