Re: [PATCH RFC v1 1/2] rcu/tree: Add basic support for kfree_rcu batching

[Joel Fernandes]

On Fri, Aug 09, 2019 at 04:22:26PM -0400, Joel Fernandes wrote:
> > > > o	With any of the above, invoke rcu_momentary_dyntick_idle() along
> > > > 	with cond_resched() in your kfree_rcu() loop.  This simulates
> > > > 	a trip to userspace for nohz_full CPUs, so if this helps for
> > > > 	non-nohz_full CPUs, adjustments to the kernel might be called for.
> 
> I did not try this yet. But I am thinking why would this help in nohz_idle
> case? In nohz_idle we already have the tick active when CPU is idle. I guess
> it is because there may be a long time that elapses before
> rcu_data.rcu_need_heavy_qs == true ?

Sorry, here I meant 'tick active when CPU is not idle'.

thanks,

 - Joel