On Thu, Jul 18, 2019 at 12:04 PM Leonardo Bras <leonardo@xxxxxxxxxxxxx> wrote: > > On Thu, 2019-07-18 at 08:19 -0400, Pavel Tatashin wrote: > > On Wed, Jul 17, 2019 at 10:42 PM Leonardo Bras <leonardo@xxxxxxxxxxxxx> wrote: > > > Adds an option on kernel config to make hot-added memory online in > > > ZONE_MOVABLE by default. > > > > > > This would be great in systems with MEMORY_HOTPLUG_DEFAULT_ONLINE=y by > > > allowing to choose which zone it will be auto-onlined > > > > This is a desired feature. From reading the code it looks to me that > > auto-selection of online method type should be done in > > memory_subsys_online(). > > > > When it is called from device online, mem->online_type should be -1: > > > > if (mem->online_type < 0) > > mem->online_type = MMOP_ONLINE_KEEP; > > > > Change it to: > > if (mem->online_type < 0) > > mem->online_type = MMOP_DEFAULT_ONLINE_TYPE; > > > > And in "linux/memory_hotplug.h" > > #ifdef CONFIG_MEMORY_HOTPLUG_MOVABLE > > #define MMOP_DEFAULT_ONLINE_TYPE MMOP_ONLINE_MOVABLE > > #else > > #define MMOP_DEFAULT_ONLINE_TYPE MMOP_ONLINE_KEEP > > #endif > > > > Could be expanded to support MMOP_ONLINE_KERNEL as well. > > > > Pasha > > Thanks for the suggestions Pasha, > > I was made aware there is a kernel boot option "movable_node" that > already creates the behavior I was trying to reproduce. I agree with others, no need to duplicate this functionality in a config, and Michal in a separate e-mail explained the reasons why we have MEMORY_HOTPLUG_DEFAULT_ONLINE. > > I was thinking of changing my patch in order to add a config option > that makes this behavior default (i.e. not need to pass it as a boot > parameter. > > Do you think that it would still be a desired feature? > > Regards, > > Leonardo Brás
