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authorJohannes Weiner <hannes@cmpxchg.org>2020-06-03 16:02:04 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2020-06-03 20:09:48 -0700
commit9d82c69438d0dff8809061edbcce43a5a4bcf09f (patch)
treeafdd01b1d6e9f81de39060c288215872b2cefddb /mm/userfaultfd.c
parent468c398233da208521a0f84c2068012a66a7489d (diff)
mm: memcontrol: convert anon and file-thp to new mem_cgroup_charge() API
With the page->mapping requirement gone from memcg, we can charge anon and file-thp pages in one single step, right after they're allocated. This removes two out of three API calls - especially the tricky commit step that needed to happen at just the right time between when the page is "set up" and when it's "published" - somewhat vague and fluid concepts that varied by page type. All we need is a freshly allocated page and a memcg context to charge. v2: prevent double charges on pre-allocated hugepages in khugepaged [hannes@cmpxchg.org: Fix crash - *hpage could be ERR_PTR instead of NULL] Link: http://lkml.kernel.org/r/20200512215813.GA487759@cmpxchg.org Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Alex Shi <alex.shi@linux.alibaba.com> Cc: Hugh Dickins <hughd@google.com> Cc: "Kirill A. Shutemov" <kirill@shutemov.name> Cc: Michal Hocko <mhocko@suse.com> Cc: Roman Gushchin <guro@fb.com> Cc: Shakeel Butt <shakeelb@google.com> Cc: Balbir Singh <bsingharora@gmail.com> Cc: Qian Cai <cai@lca.pw> Link: http://lkml.kernel.org/r/20200508183105.225460-13-hannes@cmpxchg.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/userfaultfd.c')
-rw-r--r--mm/userfaultfd.c5
1 files changed, 1 insertions, 4 deletions
diff --git a/mm/userfaultfd.c b/mm/userfaultfd.c
index 3dea268d2850..2745489415cc 100644
--- a/mm/userfaultfd.c
+++ b/mm/userfaultfd.c
@@ -56,7 +56,6 @@ static int mcopy_atomic_pte(struct mm_struct *dst_mm,
struct page **pagep,
bool wp_copy)
{
- struct mem_cgroup *memcg;
pte_t _dst_pte, *dst_pte;
spinlock_t *ptl;
void *page_kaddr;
@@ -97,7 +96,7 @@ static int mcopy_atomic_pte(struct mm_struct *dst_mm,
__SetPageUptodate(page);
ret = -ENOMEM;
- if (mem_cgroup_try_charge(page, dst_mm, GFP_KERNEL, &memcg))
+ if (mem_cgroup_charge(page, dst_mm, GFP_KERNEL, false))
goto out_release;
_dst_pte = pte_mkdirty(mk_pte(page, dst_vma->vm_page_prot));
@@ -123,7 +122,6 @@ static int mcopy_atomic_pte(struct mm_struct *dst_mm,
goto out_release_uncharge_unlock;
inc_mm_counter(dst_mm, MM_ANONPAGES);
- mem_cgroup_commit_charge(page, memcg, false);
page_add_new_anon_rmap(page, dst_vma, dst_addr, false);
lru_cache_add_active_or_unevictable(page, dst_vma);
@@ -138,7 +136,6 @@ out:
return ret;
out_release_uncharge_unlock:
pte_unmap_unlock(dst_pte, ptl);
- mem_cgroup_cancel_charge(page, memcg);
out_release:
put_page(page);
goto out;