On 07/14/2017 09:59 AM, Michal Hocko wrote: > From: Michal Hocko <[email protected]> > > boot_pageset is a boot time hack which gets superseded by normal > pagesets later in the boot process. It makes zero sense to reinitialize > it again and again during memory hotplug. > > Signed-off-by: Michal Hocko <[email protected]>
Acked-by: Vlastimil Babka <[email protected]> > --- > mm/page_alloc.c | 38 +++++++++++++++++++++----------------- > 1 file changed, 21 insertions(+), 17 deletions(-) > > diff --git a/mm/page_alloc.c b/mm/page_alloc.c > index d9f4ea057e74..7746824a425d 100644 > --- a/mm/page_alloc.c > +++ b/mm/page_alloc.c > @@ -5098,23 +5098,8 @@ static int __build_all_zonelists(void *data) > } > } > > - /* > - * Initialize the boot_pagesets that are going to be used > - * for bootstrapping processors. The real pagesets for > - * each zone will be allocated later when the per cpu > - * allocator is available. > - * > - * boot_pagesets are used also for bootstrapping offline > - * cpus if the system is already booted because the pagesets > - * are needed to initialize allocators on a specific cpu too. > - * F.e. the percpu allocator needs the page allocator which > - * needs the percpu allocator in order to allocate its pagesets > - * (a chicken-egg dilemma). > - */ > - for_each_possible_cpu(cpu) { > - setup_pageset(&per_cpu(boot_pageset, cpu), 0); > - > #ifdef CONFIG_HAVE_MEMORYLESS_NODES > + for_each_possible_cpu(cpu) { > /* > * We now know the "local memory node" for each node-- > * i.e., the node of the first zone in the generic zonelist. > @@ -5125,8 +5110,8 @@ static int __build_all_zonelists(void *data) > */ > if (cpu_online(cpu)) > set_cpu_numa_mem(cpu, > local_memory_node(cpu_to_node(cpu))); > -#endif > } > +#endif > > return 0; > } > @@ -5134,7 +5119,26 @@ static int __build_all_zonelists(void *data) > static noinline void __init > build_all_zonelists_init(void) > { > + int cpu; > + > __build_all_zonelists(NULL); > + > + /* > + * Initialize the boot_pagesets that are going to be used > + * for bootstrapping processors. The real pagesets for > + * each zone will be allocated later when the per cpu > + * allocator is available. > + * > + * boot_pagesets are used also for bootstrapping offline > + * cpus if the system is already booted because the pagesets > + * are needed to initialize allocators on a specific cpu too. > + * F.e. the percpu allocator needs the page allocator which > + * needs the percpu allocator in order to allocate its pagesets > + * (a chicken-egg dilemma). > + */ > + for_each_possible_cpu(cpu) > + setup_pageset(&per_cpu(boot_pageset, cpu), 0); > + > mminit_verify_zonelist(); > cpuset_init_current_mems_allowed(); > } >
