All callsites pass in freshly allocated pages and a valid mm. As a
result, all checks pertaining to the page's mapcount, page->mapping or the
fallback to init_mm are unneeded.
Signed-off-by: Johannes Weiner <jweiner@redhat.com>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: Michal Hocko <mhocko@suse.cz>
Cc: David Rientjes <rientjes@google.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
{
if (mem_cgroup_disabled())
return 0;
{
if (mem_cgroup_disabled())
return 0;
- /*
- * If already mapped, we don't have to account.
- * If page cache, page->mapping has address_space.
- * But page->mapping may have out-of-use anon_vma pointer,
- * detecit it by PageAnon() check. newly-mapped-anon's page->mapping
- * is NULL.
- */
- if (page_mapped(page) || (page->mapping && !PageAnon(page)))
- return 0;
- if (unlikely(!mm))
- mm = &init_mm;
+ VM_BUG_ON(page_mapped(page));
+ VM_BUG_ON(page->mapping && !PageAnon(page));
+ VM_BUG_ON(!mm);
return mem_cgroup_charge_common(page, mm, gfp_mask,
return mem_cgroup_charge_common(page, mm, gfp_mask,
- MEM_CGROUP_CHARGE_TYPE_MAPPED);
+ MEM_CGROUP_CHARGE_TYPE_MAPPED);