On Thu, Sep 29, 2022 at 4:21 AM Pingfan Liu <kernelfans@xxxxxxxxx> wrote: > > On Thu, Sep 29, 2022 at 4:19 PM Pingfan Liu <kernelfans@xxxxxxxxx> wrote: > > > [...] > > " > > > > I have no idea whether this is related to the reverted commit. > > > > I have started another test against clean v6.0-rc7 to see whether this > is an issue with the mainline. I am not sure what exactly you are reverting (you could clarify that), but if you are just removing the entire TICK_DEP_BIT_RCU, I do remember (and mentioned on IRC to others recently) that without this NOHZ_FULL has a hard time ending grace-periods because the forcing of tick is needed for this configuration if we are spinning in the kernel with the tick turned off. That seems to align with your TREE04 (NOHZ_FULL) configuration. Also, the commit Frederic suggested to revert seems to be a cosmetic optimization in the interrupt-entry path. That should not change functionality I believe. So I did not fully follow why reverting that is relevant (maybe Frederic can clarify?). Or, are you trying to just remove its use from the hotplug path? thanks, - Joel
