On Fri, Oct 04, 2019 at 05:37:28PM +0200, Sebastian Andrzej Siewior wrote: > If you post something that is related to PREEMPT_RT please keep tglx and > me in Cc. > > On 2019-10-03 11:09:06 [+0200], Daniel Wagner wrote: > > Replace preempt_enable() and preempt_disable() with the vmap_area_lock > > spin_lock instead. Calling spin_lock() with preempt disabled is > > illegal for -rt. Furthermore, enabling preemption inside the > > Looking at it again, I have reasonable doubt that this > preempt_disable() is needed. > The intention was to preload a current CPU with one extra object in non-atomic context, thus to use GFP_KERNEL permissive parameters. I.e. that allows us to avoid any allocation(if we stay on the same CPU) when we are in atomic context do splitting. If we have migrate_disable/enable, then, i think preempt_enable/disable should be replaced by it and not the way how it has been proposed in the patch. -- Vlad Rezki
