From: Johannes Weiner <hannes@cmpxchg.org>
Date: Thu, 26 Jun 2014 00:42:38 +0000 (+1000)
Subject: kernel: uprobes: switch to new memcg charge protocol
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=86eb7da5952810696c1e8ca7c94d4d937555395b;p=karo-tx-linux.git

kernel: uprobes: switch to new memcg charge protocol

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c
index d17f27c69bfc..46b7c31537ee 100644
--- a/kernel/events/uprobes.c
+++ b/kernel/events/uprobes.c
@@ -167,6 +167,11 @@ static int __replace_page(struct vm_area_struct *vma, unsigned long addr,
 	/* For mmu_notifiers */
 	const unsigned long mmun_start = addr;
 	const unsigned long mmun_end   = addr + PAGE_SIZE;
+	struct mem_cgroup *memcg;
+
+	err = mem_cgroup_try_charge(kpage, vma->vm_mm, GFP_KERNEL, &memcg);
+	if (err)
+		return err;
 
 	/* For try_to_free_swap() and munlock_vma_page() below */
 	lock_page(page);
@@ -179,6 +184,7 @@ static int __replace_page(struct vm_area_struct *vma, unsigned long addr,
 
 	get_page(kpage);
 	page_add_new_anon_rmap(kpage, vma, addr);
+	mem_cgroup_commit_charge(kpage, memcg, false);
 	lru_cache_add_active_or_unevictable(kpage, vma);
 
 	if (!PageAnon(page)) {
@@ -201,6 +207,7 @@ static int __replace_page(struct vm_area_struct *vma, unsigned long addr,
 
 	err = 0;
  unlock:
+	mem_cgroup_cancel_charge(kpage, memcg);
 	mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end);
 	unlock_page(page);
 	return err;
@@ -316,18 +323,11 @@ retry:
 	if (!new_page)
 		goto put_old;
 
-	if (mem_cgroup_charge_anon(new_page, mm, GFP_KERNEL))
-		goto put_new;
-
 	__SetPageUptodate(new_page);
 	copy_highpage(new_page, old_page);
 	copy_to_page(new_page, vaddr, &opcode, UPROBE_SWBP_INSN_SIZE);
 
 	ret = __replace_page(vma, vaddr, old_page, new_page);
-	if (ret)
-		mem_cgroup_uncharge_page(new_page);
-
-put_new:
 	page_cache_release(new_page);
 put_old:
 	put_page(old_page);