The patch titled Subject: memcg: nano-optimize VM_BUG_ON in uncharge_page has been removed from the -mm tree. Its filename was mm-memcg-avoid-page-count-check-for-zone-device-fix.patch This patch was dropped because it was folded into mm-memcg-avoid-page-count-check-for-zone-device.patch ------------------------------------------------------ From: Michal Hocko <mhocko@xxxxxxxx> Subject: memcg: nano-optimize VM_BUG_ON in uncharge_page Even though VM_BUG* is usually not compiled in there are systems which enable CONFIG_DEBUG_VM by default. VM_BUG_ON_PAGE in uncharge_page is not very optimal for the normal case. All pages should have counter==0 so that is the first thing to check. is_zone_device_page is nicely noop if ZONE_DEVICE is not compiled in and finally HW poison pages should be least probable. So reorder the check to bail out as early as possible on normal case. Link: http://lkml.kernel.org/r/20170918063141.6coovns7cb45bfly@xxxxxxxxxxxxxx Signed-off-by: Michal Hocko <mhocko@xxxxxxxx> Cc: Jérôme Glisse <jglisse@xxxxxxxxxx> Cc: Evgeny Baskakov <ebaskakov@xxxxxxxxxx> Cc: Johannes Weiner <hannes@xxxxxxxxxxx> Cc: Vladimir Davydov <vdavydov.dev@xxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/memcontrol.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff -puN mm/memcontrol.c~mm-memcg-avoid-page-count-check-for-zone-device-fix mm/memcontrol.c --- a/mm/memcontrol.c~mm-memcg-avoid-page-count-check-for-zone-device-fix +++ a/mm/memcontrol.c @@ -5658,8 +5658,8 @@ static void uncharge_batch(const struct static void uncharge_page(struct page *page, struct uncharge_gather *ug) { VM_BUG_ON_PAGE(PageLRU(page), page); - VM_BUG_ON_PAGE(!PageHWPoison(page) && !is_zone_device_page(page) && - page_count(page), page); + VM_BUG_ON_PAGE(page_count(page) && !is_zone_device_page(page) && + !PageHWPoison(page) , page); if (!page->mem_cgroup) return; _ Patches currently in -mm which might be from mhocko@xxxxxxxx are mm-oom_reaper-skip-mm-structs-with-mmu-notifiers.patch mm-memcg-remove-hotplug-locking-from-try_charge.patch mm-memcg-avoid-page-count-check-for-zone-device.patch mm-memory_hotplug-add-scheduling-point-to-__add_pages.patch mm-page_alloc-add-scheduling-point-to-memmap_init_zone.patch memremap-add-scheduling-point-to-devm_memremap_pages.patch mm-memory_hotplug-do-not-back-off-draining-pcp-free-pages-from-kworker-context.patch mm-memory_hotplug-do-not-fail-offlining-too-early.patch mm-memory_hotplug-remove-timeout-from-__offline_memory.patch mm-hugetlb-drop-hugepages_treat_as_movable-sysctl.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html