We use __free_page() to put a page to buddy system when onlining pages. __free_page() will store NR_FREE_PAGES in zone's pcp.vm_stat_diff, so we should allocate zone's pcp before onlining pages, otherwise we will lose some free pages. Cc: David Rientjes <rientjes@xxxxxxxxxx> Cc: Jiang Liu <liuj97@xxxxxxxxx> Cc: Len Brown <len.brown@xxxxxxxxx> Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx> Cc: Paul Mackerras <paulus@xxxxxxxxx> Cc: Christoph Lameter <cl@xxxxxxxxx> Cc: Minchan Kim <minchan.kim@xxxxxxxxx> Cc: KOSAKI Motohiro <kosaki.motohiro@xxxxxxxxxxxxxx> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@xxxxxxxxxxxxxx> Cc: Dave Hansen <dave@xxxxxxxxxxxxxxxxxx> Cc: Mel Gorman <mel@xxxxxxxxx> Signed-off-by: Wen Congyang <wency@xxxxxxxxxxxxxx> --- mm/memory_hotplug.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index 72f4fef..63ea7df 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -505,12 +505,16 @@ int __ref online_pages(unsigned long pfn, unsigned long nr_pages) * So, zonelist must be updated after online. */ mutex_lock(&zonelists_mutex); - if (!populated_zone(zone)) + if (!populated_zone(zone)) { need_zonelists_rebuild = 1; + build_all_zonelists(NULL, zone); + } ret = walk_system_ram_range(pfn, nr_pages, &onlined_pages, online_pages_range); if (ret) { + if (need_zonelists_rebuild) + zone_pcp_reset(zone); mutex_unlock(&zonelists_mutex); printk(KERN_DEBUG "online_pages [mem %#010llx-%#010llx] failed\n", (unsigned long long) pfn << PAGE_SHIFT, @@ -526,7 +530,7 @@ int __ref online_pages(unsigned long pfn, unsigned long nr_pages) if (onlined_pages) { node_set_state(zone_to_nid(zone), N_HIGH_MEMORY); if (need_zonelists_rebuild) - build_all_zonelists(NULL, zone); + build_all_zonelists(NULL, NULL); else zone_pcp_update(zone); } -- 1.8.0 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>