[to-be-updated] mm-charge-active-memcg-when-no-mm-is-set.patch removed from -mm tree

[to-be-updated] mm-charge-active-memcg-when-no-mm-is-set.patch removed from -mm tree

[akpm]

The patch titled
     Subject: mm: charge active memcg when no mm is set
has been removed from the -mm tree.  Its filename was
     mm-charge-active-memcg-when-no-mm-is-set.patch

This patch was dropped because an updated version will be merged

------------------------------------------------------
From: Dan Schatzberg <schatzberg.dan@gmail.com>
Subject: mm: charge active memcg when no mm is set

memalloc_use_memcg() worked for kernel allocations but was silently
ignored for user pages.

This patch establishes a precedence order for who gets charged:

1. If there is a memcg associated with the page already, that memcg is
   charged. This happens during swapin.

2. If an explicit mm is passed, mm->memcg is charged. This happens
   during page faults, which can be triggered in remote VMs (eg gup).

3. Otherwise consult the current process context. If it has configured
   a current->active_memcg, use that. Otherwise, current->mm->memcg.

Previously, if a NULL mm was passed to mem_cgroup_try_charge (case 3) it
would always charge the root cgroup.  Now it looks up the current
active_memcg first (falling back to charging the root cgroup if not set).

Link: http://lkml.kernel.org/r/4456276af198412b2d41cd09d246cd20e0c6d22a.1582581887.git.schatzberg.dan@gmail.com
Signed-off-by: Dan Schatzberg <schatzberg.dan@gmail.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Chris Down <chris@chrisdown.name>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Li Zefan <lizefan@huawei.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Roman Gushchin <guro@fb.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Yang Shi <yang.shi@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/memcontrol.c |   11 ++++++++---
 mm/shmem.c      |    4 ++--
 2 files changed, 10 insertions(+), 5 deletions(-)

--- a/mm/memcontrol.c~mm-charge-active-memcg-when-no-mm-is-set
+++ a/mm/memcontrol.c
@@ -6363,7 +6363,8 @@ out:
  * @compound: charge the page as compound or small page
  *
  * Try to charge @page to the memcg that @mm belongs to, reclaiming
- * pages according to @gfp_mask if necessary.
+ * pages according to @gfp_mask if necessary. If @mm is NULL, try to
+ * charge to the active memcg.
  *
  * Returns 0 on success, with *@memcgp pointing to the charged memcg.
  * Otherwise, an error code is returned.
@@ -6407,8 +6408,12 @@ int mem_cgroup_try_charge(struct page *p
 		}
 	}
 
-	if (!memcg)
-		memcg = get_mem_cgroup_from_mm(mm);
+	if (!memcg) {
+		if (!mm)
+			memcg = get_mem_cgroup_from_current();
+		else
+			memcg = get_mem_cgroup_from_mm(mm);
+	}
 
 	ret = try_charge(memcg, gfp_mask, nr_pages);
 
--- a/mm/shmem.c~mm-charge-active-memcg-when-no-mm-is-set
+++ a/mm/shmem.c
@@ -1619,7 +1619,7 @@ static int shmem_swapin_page(struct inod
 {
 	struct address_space *mapping = inode->i_mapping;
 	struct shmem_inode_info *info = SHMEM_I(inode);
-	struct mm_struct *charge_mm = vma ? vma->vm_mm : current->mm;
+	struct mm_struct *charge_mm = vma ? vma->vm_mm : NULL;
 	struct mem_cgroup *memcg;
 	struct page *page;
 	swp_entry_t swap;
@@ -1754,7 +1754,7 @@ repeat:
 	}
 
 	sbinfo = SHMEM_SB(inode->i_sb);
-	charge_mm = vma ? vma->vm_mm : current->mm;
+	charge_mm = vma ? vma->vm_mm : NULL;
 
 	page = find_lock_entry(mapping, index);
 	if (xa_is_value(page)) {
_

Patches currently in -mm which might be from schatzberg.dan@gmail.com are

loop-charge-i-o-to-mem-and-blk-cg.patch