From: Tal Zussman <tz2294@columbia.edu>
To: Johannes Weiner <hannes@cmpxchg.org>,
Michal Hocko <mhocko@kernel.org>,
Roman Gushchin <roman.gushchin@linux.dev>,
Shakeel Butt <shakeel.butt@linux.dev>,
Muchun Song <muchun.song@linux.dev>,
Andrew Morton <akpm@linux-foundation.org>,
Chris Li <chrisl@kernel.org>, Kairui Song <kasong@tencent.com>,
Kemeng Shi <shikemeng@huaweicloud.com>,
Nhat Pham <nphamcs@gmail.com>, Baoquan He <baoquan.he@linux.dev>,
Barry Song <baohua@kernel.org>,
Youngjun Park <youngjun.park@lge.com>,
David Hildenbrand <david@kernel.org>,
Lorenzo Stoakes <ljs@kernel.org>,
"Liam R. Howlett" <liam@infradead.org>,
Vlastimil Babka <vbabka@kernel.org>,
Mike Rapoport <rppt@kernel.org>,
Suren Baghdasaryan <surenb@google.com>,
Qi Zheng <qi.zheng@linux.dev>,
Axel Rasmussen <axelrasmussen@google.com>,
Yuanchu Xie <yuanchu@google.com>, Wei Xu <weixugc@google.com>,
"Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: cgroups@vger.kernel.org, linux-mm@kvack.org,
linux-kernel@vger.kernel.org, Tal Zussman <tz2294@columbia.edu>
Subject: [PATCH 09/11] mm: memcontrol: constify the swap accounting helpers
Date: Wed, 02 Sep 2026 15:27:55 -0400 [thread overview]
Message-ID: <20260902-folio_memcg-const-v1-9-e2c1da22246d@columbia.edu> (raw)
In-Reply-To: <20260902-folio_memcg-const-v1-0-e2c1da22246d@columbia.edu>
mem_cgroup_get_nr_swap_pages(), mem_cgroup_get_folio_swap_margin(), and
mem_cgroup_swap_full() only read swap counters and limits. Constify
them.
Remove externs from function declarations while at it.
Signed-off-by: Tal Zussman <tz2294@columbia.edu>
---
include/linux/swap.h | 12 ++++++------
mm/memcontrol.c | 6 +++---
2 files changed, 9 insertions(+), 9 deletions(-)
diff --git a/include/linux/swap.h b/include/linux/swap.h
index a72ecf12c00d..a64b5d37bf36 100644
--- a/include/linux/swap.h
+++ b/include/linux/swap.h
@@ -510,9 +510,9 @@ static inline void mem_cgroup_uncharge_swap(unsigned short id, unsigned int nr_p
__mem_cgroup_uncharge_swap(id, nr_pages);
}
-long mem_cgroup_get_folio_swap_margin(struct folio *folio);
-extern long mem_cgroup_get_nr_swap_pages(struct mem_cgroup *memcg);
-extern bool mem_cgroup_swap_full(struct folio *folio);
+long mem_cgroup_get_folio_swap_margin(const struct folio *folio);
+long mem_cgroup_get_nr_swap_pages(const struct mem_cgroup *memcg);
+bool mem_cgroup_swap_full(const struct folio *folio);
#else
static inline int mem_cgroup_try_charge_swap(struct folio *folio)
{
@@ -524,17 +524,17 @@ static inline void mem_cgroup_uncharge_swap(unsigned short id,
{
}
-static inline long mem_cgroup_get_folio_swap_margin(struct folio *folio)
+static inline long mem_cgroup_get_folio_swap_margin(const struct folio *folio)
{
return PAGE_COUNTER_MAX;
}
-static inline long mem_cgroup_get_nr_swap_pages(struct mem_cgroup *memcg)
+static inline long mem_cgroup_get_nr_swap_pages(const struct mem_cgroup *memcg)
{
return get_nr_swap_pages();
}
-static inline bool mem_cgroup_swap_full(struct folio *folio)
+static inline bool mem_cgroup_swap_full(const struct folio *folio)
{
return vm_swap_full();
}
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 3d3eadddc130..2b8705a88f6a 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -5839,7 +5839,7 @@ void __mem_cgroup_uncharge_swap(unsigned short id, unsigned int nr_pages)
rcu_read_unlock();
}
-long mem_cgroup_get_nr_swap_pages(struct mem_cgroup *memcg)
+long mem_cgroup_get_nr_swap_pages(const struct mem_cgroup *memcg)
{
long nr_swap_pages = get_nr_swap_pages();
@@ -5855,7 +5855,7 @@ long mem_cgroup_get_nr_swap_pages(struct mem_cgroup *memcg)
*
* Return: Remaining chargeable pages in the folio's memcg hierarchy.
*/
-long mem_cgroup_get_folio_swap_margin(struct folio *folio)
+long mem_cgroup_get_folio_swap_margin(const struct folio *folio)
{
struct mem_cgroup *memcg;
long margin;
@@ -5872,7 +5872,7 @@ long mem_cgroup_get_folio_swap_margin(struct folio *folio)
return margin;
}
-bool mem_cgroup_swap_full(struct folio *folio)
+bool mem_cgroup_swap_full(const struct folio *folio)
{
struct mem_cgroup *memcg;
bool ret = false;
--
2.39.5
next prev parent reply other threads:[~2026-09-02 19:28 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-09-02 19:27 [PATCH 00/11] mm: memcontrol: constify the read side of the memcg API Tal Zussman
2026-09-02 19:27 ` [PATCH 01/11] mm: memcontrol: take a const folio in folio_memcg() and friends Tal Zussman
2026-09-02 19:27 ` [PATCH 02/11] mm: memcontrol: constify obj_cgroup_memcg() " Tal Zussman
2026-09-02 19:27 ` [PATCH 03/11] mm: memcontrol: constify the lruvec helpers Tal Zussman
2026-09-04 21:35 ` Tal Zussman
2026-09-02 19:27 ` [PATCH 04/11] mm/page_io: take a const folio in bio_associate_blkg_from_folio() Tal Zussman
2026-09-02 19:27 ` [PATCH 05/11] mm: memcontrol: constify the mem_cgroup accessors Tal Zussman
2026-09-02 19:27 ` [PATCH 06/11] mm: page_counter: constify page_counter_read() and page_counter_margin() Tal Zussman
2026-09-02 19:27 ` [PATCH 07/11] mm: memcontrol: constify the reclaim protection helpers Tal Zussman
2026-09-02 19:27 ` [PATCH 08/11] mm: memcontrol: constify the memcg and lruvec stat readers Tal Zussman
2026-09-04 21:42 ` Tal Zussman
2026-09-02 19:27 ` Tal Zussman [this message]
2026-09-02 19:27 ` [PATCH 10/11] mm: memcontrol: constify mem_cgroup_swappiness() and mem_cgroup_get_max() Tal Zussman
2026-09-02 19:27 ` [PATCH 11/11] mm: memcontrol: constify the zswap and socket pressure helpers Tal Zussman
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