[PATCH 17/18] mm: memcontrol: delete unused lrucare handling

From: Johannes Weiner
Date: Mon Apr 20 2020 - 18:12:24 EST

Signed-off-by: Johannes Weiner <hannes@xxxxxxxxxxx>
---
include/linux/memcontrol.h | 5 ++--
kernel/events/uprobes.c | 3 +-
mm/filemap.c | 2 +-
mm/huge_memory.c | 7 ++---
mm/khugepaged.c | 4 +--
mm/memcontrol.c | 57 +++-----------------------------------
mm/memory.c | 8 +++---
mm/migrate.c | 2 +-
mm/shmem.c | 2 +-
mm/swap_state.c | 2 +-
mm/userfaultfd.c | 2 +-
11 files changed, 21 insertions(+), 73 deletions(-)

diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index d458f1d90aa4..4b868e5a687f 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -357,8 +357,7 @@ static inline unsigned long mem_cgroup_protection(struct mem_cgroup *memcg,
enum mem_cgroup_protection mem_cgroup_protected(struct mem_cgroup *root,
struct mem_cgroup *memcg);

-int mem_cgroup_charge(struct page *page, struct mm_struct *mm, gfp_t gfp_mask,
- bool lrucare);
+int mem_cgroup_charge(struct page *page, struct mm_struct *mm, gfp_t gfp_mask);

void mem_cgroup_uncharge(struct page *page);
void mem_cgroup_uncharge_list(struct list_head *page_list);
@@ -839,7 +838,7 @@ static inline enum mem_cgroup_protection mem_cgroup_protected(
}

static inline int mem_cgroup_charge(struct page *page, struct mm_struct *mm,
- gfp_t gfp_mask, bool lrucare)
+ gfp_t gfp_mask)
{
return 0;
}
diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c
index 4253c153e985..eddc8db96027 100644
--- a/kernel/events/uprobes.c
+++ b/kernel/events/uprobes.c
@@ -167,8 +167,7 @@ static int __replace_page(struct vm_area_struct *vma, unsigned long addr,
addr + PAGE_SIZE);

if (new_page) {
- err = mem_cgroup_charge(new_page, vma->vm_mm, GFP_KERNEL,
- false);
+ err = mem_cgroup_charge(new_page, vma->vm_mm, GFP_KERNEL);
if (err)
return err;
}
diff --git a/mm/filemap.c b/mm/filemap.c
index a10bd6696049..f73b221314df 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -845,7 +845,7 @@ static int __add_to_page_cache_locked(struct page *page,
page->index = offset;

if (!huge) {
- error = mem_cgroup_charge(page, current->mm, gfp_mask, false);
+ error = mem_cgroup_charge(page, current->mm, gfp_mask);
if (error)
goto error;
}
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 0b33eaf0740a..35a716720e26 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -593,7 +593,7 @@ static vm_fault_t __do_huge_pmd_anonymous_page(struct vm_fault *vmf,

VM_BUG_ON_PAGE(!PageCompound(page), page);

- if (mem_cgroup_charge(page, vma->vm_mm, gfp, false)) {
+ if (mem_cgroup_charge(page, vma->vm_mm, gfp)) {
put_page(page);
count_vm_event(THP_FAULT_FALLBACK);
count_vm_event(THP_FAULT_FALLBACK_CHARGE);
@@ -1276,7 +1276,7 @@ static vm_fault_t do_huge_pmd_wp_page_fallback(struct vm_fault *vmf,
vmf->address, page_to_nid(page));
if (unlikely(!pages[i] ||
mem_cgroup_charge(pages[i], vma->vm_mm,
- GFP_KERNEL, false))) {
+ GFP_KERNEL))) {
if (pages[i])
put_page(pages[i]);
while (--i >= 0)
@@ -1430,8 +1430,7 @@ vm_fault_t do_huge_pmd_wp_page(struct vm_fault *vmf, pmd_t orig_pmd)
goto out;
}

- if (unlikely(mem_cgroup_charge(new_page, vma->vm_mm, huge_gfp,
- false))) {
+ if (unlikely(mem_cgroup_charge(new_page, vma->vm_mm, huge_gfp))) {
put_page(new_page);
split_huge_pmd(vma, vmf->pmd, vmf->address);
if (page)
diff --git a/mm/khugepaged.c b/mm/khugepaged.c
index 5cf8082fb038..28c6d84db4ee 100644
--- a/mm/khugepaged.c
+++ b/mm/khugepaged.c
@@ -973,7 +973,7 @@ static void collapse_huge_page(struct mm_struct *mm,
goto out_nolock;
}

- if (unlikely(mem_cgroup_charge(new_page, mm, gfp, false))) {
+ if (unlikely(mem_cgroup_charge(new_page, mm, gfp))) {
result = SCAN_CGROUP_CHARGE_FAIL;
goto out_nolock;
}
@@ -1527,7 +1527,7 @@ static void collapse_file(struct mm_struct *mm,
goto out;
}

- if (unlikely(mem_cgroup_charge(new_page, mm, gfp, false))) {
+ if (unlikely(mem_cgroup_charge(new_page, mm, gfp))) {
result = SCAN_CGROUP_CHARGE_FAIL;
goto out;
}
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 1d7408a8744a..a8cce52b6b4d 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -2601,51 +2601,9 @@ static void cancel_charge(struct mem_cgroup *memcg, unsigned int nr_pages)
css_put_many(&memcg->css, nr_pages);
}

-static void lock_page_lru(struct page *page, int *isolated)
+static void commit_charge(struct page *page, struct mem_cgroup *memcg)
{
- pg_data_t *pgdat = page_pgdat(page);
-
- spin_lock_irq(&pgdat->lru_lock);
- if (PageLRU(page)) {
- struct lruvec *lruvec;
-
- lruvec = mem_cgroup_page_lruvec(page, pgdat);
- ClearPageLRU(page);
- del_page_from_lru_list(page, lruvec, page_lru(page));
- *isolated = 1;
- } else
- *isolated = 0;
-}
-
-static void unlock_page_lru(struct page *page, int isolated)
-{
- pg_data_t *pgdat = page_pgdat(page);
-
- if (isolated) {
- struct lruvec *lruvec;
-
- lruvec = mem_cgroup_page_lruvec(page, pgdat);
- VM_BUG_ON_PAGE(PageLRU(page), page);
- SetPageLRU(page);
- add_page_to_lru_list(page, lruvec, page_lru(page));
- }
- spin_unlock_irq(&pgdat->lru_lock);
-}
-
-static void commit_charge(struct page *page, struct mem_cgroup *memcg,
- bool lrucare)
-{
- int isolated;
-
VM_BUG_ON_PAGE(page->mem_cgroup, page);
-
- /*
- * In some cases, SwapCache and FUSE(splice_buf->radixtree), the page
- * may already be on some other mem_cgroup's LRU. Take care of it.
- */
- if (lrucare)
- lock_page_lru(page, &isolated);
-
/*
* Nobody should be changing or seriously looking at
* page->mem_cgroup at this point:
@@ -2661,9 +2619,6 @@ static void commit_charge(struct page *page, struct mem_cgroup *memcg,
* have the page locked
*/
page->mem_cgroup = memcg;
-
- if (lrucare)
- unlock_page_lru(page, isolated);
}

#ifdef CONFIG_MEMCG_KMEM
@@ -6433,22 +6388,18 @@ enum mem_cgroup_protection mem_cgroup_protected(struct mem_cgroup *root,
* @page: page to charge
* @mm: mm context of the victim
* @gfp_mask: reclaim mode
- * @lrucare: page might be on the LRU already
*
* Try to charge @page to the memcg that @mm belongs to, reclaiming
* pages according to @gfp_mask if necessary.
*
* Returns 0 on success. Otherwise, an error code is returned.
*/
-int mem_cgroup_charge(struct page *page, struct mm_struct *mm, gfp_t gfp_mask,
- bool lrucare)
+int mem_cgroup_charge(struct page *page, struct mm_struct *mm, gfp_t gfp_mask)
{
unsigned int nr_pages = hpage_nr_pages(page);
struct mem_cgroup *memcg = NULL;
int ret = 0;

- VM_BUG_ON_PAGE(PageLRU(page) && !lrucare, page);
-
if (mem_cgroup_disabled())
goto out;

@@ -6482,7 +6433,7 @@ int mem_cgroup_charge(struct page *page, struct mm_struct *mm, gfp_t gfp_mask,
if (ret)
goto out_put;

- commit_charge(page, memcg, lrucare);
+ commit_charge(page, memcg);

local_irq_disable();
mem_cgroup_charge_statistics(memcg, page, nr_pages);
@@ -6685,7 +6636,7 @@ void mem_cgroup_migrate(struct page *oldpage, struct page *newpage)
page_counter_charge(&memcg->memsw, nr_pages);
css_get_many(&memcg->css, nr_pages);

- commit_charge(newpage, memcg, false);
+ commit_charge(newpage, memcg);

local_irq_save(flags);
mem_cgroup_charge_statistics(memcg, newpage, nr_pages);
diff --git a/mm/memory.c b/mm/memory.c
index 5d266532fc40..0ad4db56bea2 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -2677,7 +2677,7 @@ static vm_fault_t wp_page_copy(struct vm_fault *vmf)
}
}

- if (mem_cgroup_charge(new_page, mm, GFP_KERNEL, false))
+ if (mem_cgroup_charge(new_page, mm, GFP_KERNEL))
goto oom_free_new;
cgroup_throttle_swaprate(new_page, GFP_KERNEL);

@@ -3136,7 +3136,7 @@ vm_fault_t do_swap_page(struct vm_fault *vmf)
/* Tell memcg to use swap ownership records */
SetPageSwapCache(page);
err = mem_cgroup_charge(page, vma->vm_mm,
- GFP_KERNEL, false);
+ GFP_KERNEL);
ClearPageSwapCache(page);
if (err)
goto out_page;
@@ -3360,7 +3360,7 @@ static vm_fault_t do_anonymous_page(struct vm_fault *vmf)
if (!page)
goto oom;

- if (mem_cgroup_charge(page, vma->vm_mm, GFP_KERNEL, false))
+ if (mem_cgroup_charge(page, vma->vm_mm, GFP_KERNEL))
goto oom_free_page;
cgroup_throttle_swaprate(page, GFP_KERNEL);

@@ -3856,7 +3856,7 @@ static vm_fault_t do_cow_fault(struct vm_fault *vmf)
if (!vmf->cow_page)
return VM_FAULT_OOM;

- if (mem_cgroup_charge(vmf->cow_page, vma->vm_mm, GFP_KERNEL, false)) {
+ if (mem_cgroup_charge(vmf->cow_page, vma->vm_mm, GFP_KERNEL)) {
put_page(vmf->cow_page);
return VM_FAULT_OOM;
}
diff --git a/mm/migrate.c b/mm/migrate.c
index a3361c744069..ced652d069ee 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -2792,7 +2792,7 @@ static void migrate_vma_insert_page(struct migrate_vma *migrate,

if (unlikely(anon_vma_prepare(vma)))
goto abort;
- if (mem_cgroup_charge(page, vma->vm_mm, GFP_KERNEL, false))
+ if (mem_cgroup_charge(page, vma->vm_mm, GFP_KERNEL))
goto abort;

/*
diff --git a/mm/shmem.c b/mm/shmem.c
index 966f150a4823..add10d448bc6 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -624,7 +624,7 @@ static int shmem_add_to_page_cache(struct page *page,
page->index = index;

if (!PageSwapCache(page)) {
- error = mem_cgroup_charge(page, charge_mm, gfp, false);
+ error = mem_cgroup_charge(page, charge_mm, gfp);
if (error) {
if (PageTransHuge(page)) {
count_vm_event(THP_FILE_FALLBACK);
diff --git a/mm/swap_state.c b/mm/swap_state.c
index f3b9073bfff3..26fded65c30d 100644
--- a/mm/swap_state.c
+++ b/mm/swap_state.c
@@ -427,7 +427,7 @@ struct page *__read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask,
if (add_to_swap_cache(page, entry, gfp_mask & GFP_KERNEL))
goto fail_unlock;

- if (mem_cgroup_charge(page, NULL, gfp_mask & GFP_KERNEL, false))
+ if (mem_cgroup_charge(page, NULL, gfp_mask & GFP_KERNEL))
goto fail_delete;

/* Initiate read into locked page */
diff --git a/mm/userfaultfd.c b/mm/userfaultfd.c
index 2745489415cc..7f5194046b01 100644
--- a/mm/userfaultfd.c
+++ b/mm/userfaultfd.c
@@ -96,7 +96,7 @@ static int mcopy_atomic_pte(struct mm_struct *dst_mm,
__SetPageUptodate(page);

ret = -ENOMEM;
- if (mem_cgroup_charge(page, dst_mm, GFP_KERNEL, false))
+ if (mem_cgroup_charge(page, dst_mm, GFP_KERNEL))
goto out_release;

_dst_pte = pte_mkdirty(mk_pte(page, dst_vma->vm_page_prot));
--
2.26.0