From 9d82c69438d0dff8809061edbcce43a5a4bcf09f Mon Sep 17 00:00:00 2001 From: Johannes Weiner Date: Wed, 3 Jun 2020 16:02:04 -0700 Subject: 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 Signed-off-by: Andrew Morton Reviewed-by: Joonsoo Kim Cc: Alex Shi Cc: Hugh Dickins Cc: "Kirill A. Shutemov" Cc: Michal Hocko Cc: Roman Gushchin Cc: Shakeel Butt Cc: Balbir Singh Cc: Qian Cai Link: http://lkml.kernel.org/r/20200508183105.225460-13-hannes@cmpxchg.org Signed-off-by: Linus Torvalds --- kernel/events/uprobes.c | 11 +++-------- 1 file changed, 3 insertions(+), 8 deletions(-) (limited to 'kernel') diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c index 89ef81b65bcb..4253c153e985 100644 --- a/kernel/events/uprobes.c +++ b/kernel/events/uprobes.c @@ -162,14 +162,13 @@ static int __replace_page(struct vm_area_struct *vma, unsigned long addr, }; int err; struct mmu_notifier_range range; - struct mem_cgroup *memcg; mmu_notifier_range_init(&range, MMU_NOTIFY_CLEAR, 0, vma, mm, addr, addr + PAGE_SIZE); if (new_page) { - err = mem_cgroup_try_charge(new_page, vma->vm_mm, GFP_KERNEL, - &memcg); + err = mem_cgroup_charge(new_page, vma->vm_mm, GFP_KERNEL, + false); if (err) return err; } @@ -179,16 +178,12 @@ static int __replace_page(struct vm_area_struct *vma, unsigned long addr, mmu_notifier_invalidate_range_start(&range); err = -EAGAIN; - if (!page_vma_mapped_walk(&pvmw)) { - if (new_page) - mem_cgroup_cancel_charge(new_page, memcg); + if (!page_vma_mapped_walk(&pvmw)) goto unlock; - } VM_BUG_ON_PAGE(addr != pvmw.address, old_page); if (new_page) { get_page(new_page); - mem_cgroup_commit_charge(new_page, memcg, false); page_add_new_anon_rmap(new_page, vma, addr, false); lru_cache_add_active_or_unevictable(new_page, vma); } else -- cgit v1.2.3-59-g8ed1b