From: Charan Teja Reddy <charante@xxxxxxxxxxxxxx> Subject: mm, memory_hotplug: update pcp lists everytime onlining a memory block When onlining a first memory block in a zone, pcp lists are not updated thus pcp struct will have the default setting of ->high = 0,->batch = 1. This means till the second memory block in a zone(if it have) is onlined the pcp lists of this zone will not contain any pages because pcp's ->count is always greater than ->high thus free_pcppages_bulk() is called to free batch size(=1) pages every time system wants to add a page to the pcp list through free_unref_page(). To put this in a word, system is not using benefits offered by the pcp lists when there is a single onlineable memory block in a zone. Correct this by always updating the pcp lists when memory block is onlined. Link: http://lkml.kernel.org/r/1596372896-15336-1-git-send-email-charante@xxxxxxxxxxxxxx Fixes: 1f522509c77a ("mem-hotplug: avoid multiple zones sharing same boot strapping boot_pageset") Signed-off-by: Charan Teja Reddy <charante@xxxxxxxxxxxxxx> Reviewed-by: David Hildenbrand <david@xxxxxxxxxx> Acked-by: Vlastimil Babka <vbabka@xxxxxxx> Acked-by: Michal Hocko <mhocko@xxxxxxxx> Cc: Vinayak Menon <vinmenon@xxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/memory_hotplug.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) --- a/mm/memory_hotplug.c~mm-memory_hotplug-update-pcp-lists-everytime-onlining-a-memory-block +++ a/mm/memory_hotplug.c @@ -854,8 +854,7 @@ int __ref online_pages(unsigned long pfn node_states_set_node(nid, &arg); if (need_zonelists_rebuild) build_all_zonelists(NULL); - else - zone_pcp_update(zone); + zone_pcp_update(zone); init_per_zone_wmark_min(); _
