[PATCH v13 042/137] mm/memcg: Convert mem_cgroup_uncharge() to take a folio

Matthew Wilcox (Oracle)
2021-07-12T03:30:33Z

Convert all the callers to call page_folio(). Most of them were already
using a head page, but a few of them I can't prove were, so this may
actually fix a bug.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
---
include/linux/memcontrol.h | 4 ++--
mm/filemap.c | 2 +-
mm/khugepaged.c | 4 ++--
mm/memcontrol.c | 14 +++++++-------
mm/memory-failure.c | 2 +-
mm/memremap.c | 2 +-
mm/page_alloc.c | 2 +-
mm/swap.c | 2 +-
8 files changed, 16 insertions(+), 16 deletions(-)

diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index ce250303d3a5..11486ef4776e 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -709,7 +709,7 @@ int mem_cgroup_swapin_charge_page(struct page *page, struct mm_struct *mm,
gfp_t gfp, swp_entry_t entry);
void mem_cgroup_swapin_uncharge_swap(swp_entry_t entry);

-void mem_cgroup_uncharge(struct page *page);
+void mem_cgroup_uncharge(struct folio *folio);
void mem_cgroup_uncharge_list(struct list_head *page_list);

void mem_cgroup_migrate(struct page *oldpage, struct page *newpage);
@@ -1201,7 +1201,7 @@ static inline void mem_cgroup_swapin_uncharge_swap(swp_entry_t entry)
{
}

-static inline void mem_cgroup_uncharge(struct page *page)
+static inline void mem_cgroup_uncharge(struct folio *folio)
{
}

diff --git a/mm/filemap.c b/mm/filemap.c
index 44498bfe7b45..b8be62793316 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -923,7 +923,7 @@ noinline int __add_to_page_cache_locked(struct page *page,
if (xas_error(&xas)) {
error = xas_error(&xas);
if (charged)
- mem_cgroup_uncharge(page);
+ mem_cgroup_uncharge(page_folio(page));
goto error;
}

diff --git a/mm/khugepaged.c b/mm/khugepaged.c
index 8f6d7fdea9f4..6b9c98ddcd09 100644
--- a/mm/khugepaged.c
+++ b/mm/khugepaged.c
@@ -1211,7 +1211,7 @@ static void collapse_huge_page(struct mm_struct *mm,
mmap_write_unlock(mm);
out_nolock:
if (!IS_ERR_OR_NULL(*hpage))
- mem_cgroup_uncharge(*hpage);
+ mem_cgroup_uncharge(page_folio(*hpage));
trace_mm_collapse_huge_page(mm, isolated, result);
return;
}
@@ -1975,7 +1975,7 @@ static void collapse_file(struct mm_struct *mm,
out:
VM_BUG_ON(!list_empty(&pagelist));
if (!IS_ERR_OR_NULL(*hpage))
- mem_cgroup_uncharge(*hpage);
+ mem_cgroup_uncharge(page_folio(*hpage));
/* TODO: tracepoints */
}

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 2436ad3841d8..c787a87a54ff 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -6897,24 +6897,24 @@ static void uncharge_folio(struct folio *folio, struct uncharge_gather *ug)
}

/**
- * mem_cgroup_uncharge - uncharge a page
- * @page: page to uncharge
+ * mem_cgroup_uncharge - Uncharge a folio.
+ * @folio: Folio to uncharge.
*
- * Uncharge a page previously charged with mem_cgroup_charge().
+ * Uncharge a folio previously charged with folio_charge_cgroup().
*/
-void mem_cgroup_uncharge(struct page *page)
+void mem_cgroup_uncharge(struct folio *folio)
{
struct uncharge_gather ug;

if (mem_cgroup_disabled())
return;

- /* Don't touch page->lru of any random page, pre-check: */
- if (!page_memcg(page))
+ /* Don't touch folio->lru of any random page, pre-check: */
+ if (!folio_memcg(folio))
return;

uncharge_gather_clear(&ug);
- uncharge_folio(page_folio(page), &ug);
+ uncharge_folio(folio, &ug);
uncharge_batch(&ug);
}

diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index eefd823deb67..9ae7a57a4cc0 100644
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -763,7 +763,7 @@ static int delete_from_lru_cache(struct page *p)
* Poisoned page might never drop its ref count to 0 so we have
* to uncharge it manually from its memcg.
*/
- mem_cgroup_uncharge(p);
+ mem_cgroup_uncharge(page_folio(p));

/*
* drop the page count elevated by isolate_lru_page()
diff --git a/mm/memremap.c b/mm/memremap.c
index 15a074ffb8d7..6eac40f9f62a 100644
--- a/mm/memremap.c
+++ b/mm/memremap.c
@@ -508,7 +508,7 @@ void free_devmap_managed_page(struct page *page)

__ClearPageWaiters(page);

- mem_cgroup_uncharge(page);
+ mem_cgroup_uncharge(page_folio(page));

/*
* When a device_private page is freed, the page->mapping field
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 3b97e17806be..d72a0d9d4184 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -726,7 +726,7 @@ static inline void free_the_page(struct page *page, unsigned int order)

void free_compound_page(struct page *page)
{
- mem_cgroup_uncharge(page);
+ mem_cgroup_uncharge(page_folio(page));
free_the_page(page, compound_order(page));
}

diff --git a/mm/swap.c b/mm/swap.c
index 6d4696eb2d43..b28c76a2e955 100644
--- a/mm/swap.c
+++ b/mm/swap.c
@@ -94,7 +94,7 @@ static void __page_cache_release(struct page *page)
static void __put_single_page(struct page *page)
{
__page_cache_release(page);
- mem_cgroup_uncharge(page);
+ mem_cgroup_uncharge(page_folio(page));
free_unref_page(page, 0);
}

--
2.30.2