Re: Memory hotplug not increasing the total RAM

2018-01-30 Thread Pavel Tatashin
> You might be very well correct but the hotplug code is quite subtle and > we do depend on PageReserved at some unexpected places so it is not that > easy I am afraid. My TODO list in the hotplug is quite long. If you feel > like you want to work on that I would be more than happy. You are correc

Re: Memory hotplug not increasing the total RAM

2018-01-30 Thread Michal Hocko
On Tue 30-01-18 13:11:06, Pavel Tatashin wrote: > Hi Michal, > > Thank you for taking care of the problem. The patch may introduce a > small performance regression during normal boot, as we add a branch > into a hot initialization path. But, it fixes a current problem, so: > > Reviewed-by: Pavel

Re: Memory hotplug not increasing the total RAM

2018-01-30 Thread Pavel Tatashin
Hi Michal, Thank you for taking care of the problem. The patch may introduce a small performance regression during normal boot, as we add a branch into a hot initialization path. But, it fixes a current problem, so: Reviewed-by: Pavel Tatashin However, I think we should change the hotplug code

Re: Memory hotplug not increasing the total RAM

2018-01-30 Thread Michal Hocko
[Cc Andrew - thread starts here http://lkml.kernel.org/r/20180130083006.gb1...@in.ibm.com] On Tue 30-01-18 15:23:45, Bharata B Rao wrote: > On Tue, Jan 30, 2018 at 10:28:15AM +0100, Michal Hocko wrote: > > On Tue 30-01-18 10:16:00, Michal Hocko wrote: > > > On Tue 30-01-18 14:00:06, Bharata B Rao

Re: Memory hotplug not increasing the total RAM

2018-01-30 Thread Bharata B Rao
On Tue, Jan 30, 2018 at 10:28:15AM +0100, Michal Hocko wrote: > On Tue 30-01-18 10:16:00, Michal Hocko wrote: > > On Tue 30-01-18 14:00:06, Bharata B Rao wrote: > > > Hi, > > > > > > With the latest upstream, I see that memory hotplug is not working > > > as expected. The hotplugged memory isn't s

Re: Memory hotplug not increasing the total RAM

2018-01-30 Thread Michal Hocko
On Tue 30-01-18 10:16:00, Michal Hocko wrote: > On Tue 30-01-18 14:00:06, Bharata B Rao wrote: > > Hi, > > > > With the latest upstream, I see that memory hotplug is not working > > as expected. The hotplugged memory isn't seen to increase the total > > RAM pages. This has been observed with both

Re: Memory hotplug not increasing the total RAM

2018-01-30 Thread Michal Hocko
On Tue 30-01-18 14:00:06, Bharata B Rao wrote: > Hi, > > With the latest upstream, I see that memory hotplug is not working > as expected. The hotplugged memory isn't seen to increase the total > RAM pages. This has been observed with both x86 and Power guests. > > 1. Memory hotplug code intially

Memory hotplug not increasing the total RAM

2018-01-30 Thread Bharata B Rao
Hi, With the latest upstream, I see that memory hotplug is not working as expected. The hotplugged memory isn't seen to increase the total RAM pages. This has been observed with both x86 and Power guests. 1. Memory hotplug code intially marks pages as PageReserved via __add_section(). 2. Later th