From: Roman Gushchin <guro@fb.com>
To: <bpf@vger.kernel.org>
Cc: <ast@kernel.org>, <daniel@iogearbox.net>,
<netdev@vger.kernel.org>, <andrii@kernel.org>,
<akpm@linux-foundation.org>, <linux-mm@kvack.org>,
<linux-kernel@vger.kernel.org>, <kernel-team@fb.com>
Subject: [PATCH bpf-next v7 02/34] mm: memcontrol/slab: use helpers to access slab page's memcg_data
Date: Thu, 19 Nov 2020 09:37:22 -0800 [thread overview]
Message-ID: <20201119173754.4125257-3-guro@fb.com> (raw)
In-Reply-To: <20201119173754.4125257-1-guro@fb.com>
To gather all direct accesses to struct page's memcg_data field in one
place, let's introduce 3 new helpers to use in the slab accounting code:
struct obj_cgroup **page_objcgs(struct page *page);
struct obj_cgroup **page_objcgs_check(struct page *page);
bool set_page_objcgs(struct page *page, struct obj_cgroup **objcgs);
They are similar to the corresponding API for generic pages, except that
the setter can return false, indicating that the value has been already
set from a different thread.
Link: https://lkml.kernel.org/r/20201027001657.3398190-3-guro@fb.com
Signed-off-by: Roman Gushchin <guro@fb.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
include/linux/memcontrol.h | 64 ++++++++++++++++++++++++++++++++++++++
mm/memcontrol.c | 6 ++--
mm/slab.h | 35 +++++----------------
3 files changed, 75 insertions(+), 30 deletions(-)
diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index f95c1433461c..c7ac0a5b8989 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -416,6 +416,70 @@ static inline struct mem_cgroup *page_memcg_check(struct page *page)
return (struct mem_cgroup *)memcg_data;
}
+#ifdef CONFIG_MEMCG_KMEM
+/*
+ * page_objcgs - get the object cgroups vector associated with a page
+ * @page: a pointer to the page struct
+ *
+ * Returns a pointer to the object cgroups vector associated with the page,
+ * or NULL. This function assumes that the page is known to have an
+ * associated object cgroups vector. It's not safe to call this function
+ * against pages, which might have an associated memory cgroup: e.g.
+ * kernel stack pages.
+ */
+static inline struct obj_cgroup **page_objcgs(struct page *page)
+{
+ return (struct obj_cgroup **)(READ_ONCE(page->memcg_data) & ~0x1UL);
+}
+
+/*
+ * page_objcgs_check - get the object cgroups vector associated with a page
+ * @page: a pointer to the page struct
+ *
+ * Returns a pointer to the object cgroups vector associated with the page,
+ * or NULL. This function is safe to use if the page can be directly associated
+ * with a memory cgroup.
+ */
+static inline struct obj_cgroup **page_objcgs_check(struct page *page)
+{
+ unsigned long memcg_data = READ_ONCE(page->memcg_data);
+
+ if (memcg_data && (memcg_data & 0x1UL))
+ return (struct obj_cgroup **)(memcg_data & ~0x1UL);
+
+ return NULL;
+}
+
+/*
+ * set_page_objcgs - associate a page with a object cgroups vector
+ * @page: a pointer to the page struct
+ * @objcgs: a pointer to the object cgroups vector
+ *
+ * Atomically associates a page with a vector of object cgroups.
+ */
+static inline bool set_page_objcgs(struct page *page,
+ struct obj_cgroup **objcgs)
+{
+ return !cmpxchg(&page->memcg_data, 0, (unsigned long)objcgs | 0x1UL);
+}
+#else
+static inline struct obj_cgroup **page_objcgs(struct page *page)
+{
+ return NULL;
+}
+
+static inline struct obj_cgroup **page_objcgs_check(struct page *page)
+{
+ return NULL;
+}
+
+static inline bool set_page_objcgs(struct page *page,
+ struct obj_cgroup **objcgs)
+{
+ return true;
+}
+#endif
+
static __always_inline bool memcg_stat_item_in_bytes(int idx)
{
if (idx == MEMCG_PERCPU_B)
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 3968d68503cb..0054b4846770 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -2899,7 +2899,7 @@ int memcg_alloc_page_obj_cgroups(struct page *page, struct kmem_cache *s,
if (!vec)
return -ENOMEM;
- if (cmpxchg(&page->memcg_data, 0, (unsigned long)vec | 0x1UL))
+ if (!set_page_objcgs(page, vec))
kfree(vec);
else
kmemleak_not_leak(vec);
@@ -2933,12 +2933,12 @@ struct mem_cgroup *mem_cgroup_from_obj(void *p)
* Memcg membership data for each individual object is saved in
* the page->obj_cgroups.
*/
- if (page_has_obj_cgroups(page)) {
+ if (page_objcgs_check(page)) {
struct obj_cgroup *objcg;
unsigned int off;
off = obj_to_index(page->slab_cache, page, p);
- objcg = page_obj_cgroups(page)[off];
+ objcg = page_objcgs(page)[off];
if (objcg)
return obj_cgroup_memcg(objcg);
diff --git a/mm/slab.h b/mm/slab.h
index e2535cee0d33..9a54a0cb5cca 100644
--- a/mm/slab.h
+++ b/mm/slab.h
@@ -239,28 +239,12 @@ static inline bool kmem_cache_debug_flags(struct kmem_cache *s, slab_flags_t fla
}
#ifdef CONFIG_MEMCG_KMEM
-static inline struct obj_cgroup **page_obj_cgroups(struct page *page)
-{
- /*
- * Page's memory cgroup and obj_cgroups vector are sharing the same
- * space. To distinguish between them in case we don't know for sure
- * that the page is a slab page (e.g. page_cgroup_ino()), let's
- * always set the lowest bit of obj_cgroups.
- */
- return (struct obj_cgroup **)(page->memcg_data & ~0x1UL);
-}
-
-static inline bool page_has_obj_cgroups(struct page *page)
-{
- return page->memcg_data & 0x1UL;
-}
-
int memcg_alloc_page_obj_cgroups(struct page *page, struct kmem_cache *s,
gfp_t gfp);
static inline void memcg_free_page_obj_cgroups(struct page *page)
{
- kfree(page_obj_cgroups(page));
+ kfree(page_objcgs(page));
page->memcg_data = 0;
}
@@ -322,7 +306,7 @@ static inline void memcg_slab_post_alloc_hook(struct kmem_cache *s,
if (likely(p[i])) {
page = virt_to_head_page(p[i]);
- if (!page_has_obj_cgroups(page) &&
+ if (!page_objcgs(page) &&
memcg_alloc_page_obj_cgroups(page, s, flags)) {
obj_cgroup_uncharge(objcg, obj_full_size(s));
continue;
@@ -330,7 +314,7 @@ static inline void memcg_slab_post_alloc_hook(struct kmem_cache *s,
off = obj_to_index(s, page, p[i]);
obj_cgroup_get(objcg);
- page_obj_cgroups(page)[off] = objcg;
+ page_objcgs(page)[off] = objcg;
mod_objcg_state(objcg, page_pgdat(page),
cache_vmstat_idx(s), obj_full_size(s));
} else {
@@ -344,6 +328,7 @@ static inline void memcg_slab_free_hook(struct kmem_cache *s_orig,
void **p, int objects)
{
struct kmem_cache *s;
+ struct obj_cgroup **objcgs;
struct obj_cgroup *objcg;
struct page *page;
unsigned int off;
@@ -357,7 +342,8 @@ static inline void memcg_slab_free_hook(struct kmem_cache *s_orig,
continue;
page = virt_to_head_page(p[i]);
- if (!page_has_obj_cgroups(page))
+ objcgs = page_objcgs(page);
+ if (!objcgs)
continue;
if (!s_orig)
@@ -366,11 +352,11 @@ static inline void memcg_slab_free_hook(struct kmem_cache *s_orig,
s = s_orig;
off = obj_to_index(s, page, p[i]);
- objcg = page_obj_cgroups(page)[off];
+ objcg = objcgs[off];
if (!objcg)
continue;
- page_obj_cgroups(page)[off] = NULL;
+ objcgs[off] = NULL;
obj_cgroup_uncharge(objcg, obj_full_size(s));
mod_objcg_state(objcg, page_pgdat(page), cache_vmstat_idx(s),
-obj_full_size(s));
@@ -379,11 +365,6 @@ static inline void memcg_slab_free_hook(struct kmem_cache *s_orig,
}
#else /* CONFIG_MEMCG_KMEM */
-static inline bool page_has_obj_cgroups(struct page *page)
-{
- return false;
-}
-
static inline struct mem_cgroup *memcg_from_slab_obj(void *ptr)
{
return NULL;
--
2.26.2
next prev parent reply other threads:[~2020-11-19 17:38 UTC|newest]
Thread overview: 48+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-11-19 17:37 [PATCH bpf-next v7 00/34] bpf: switch to memcg-based memory accounting Roman Gushchin
2020-11-19 17:37 ` [PATCH bpf-next v7 01/34] mm: memcontrol: use helpers to read page's memcg data Roman Gushchin
2020-11-19 17:37 ` Roman Gushchin [this message]
2020-11-19 17:37 ` [PATCH bpf-next v7 03/34] mm: introduce page memcg flags Roman Gushchin
2020-11-19 17:37 ` [PATCH bpf-next v7 04/34] mm: convert page kmemcg type to a page memcg flag Roman Gushchin
2020-11-19 17:37 ` [PATCH bpf-next v7 05/34] bpf: memcg-based memory accounting for bpf progs Roman Gushchin
2020-11-19 17:37 ` [PATCH bpf-next v7 06/34] bpf: prepare for memcg-based memory accounting for bpf maps Roman Gushchin
2020-11-20 1:05 ` Song Liu
2020-11-19 17:37 ` [PATCH bpf-next v7 07/34] bpf: " Roman Gushchin
2020-11-19 17:37 ` [PATCH bpf-next v7 08/34] bpf: refine memcg-based memory accounting for arraymap maps Roman Gushchin
2020-11-19 17:37 ` [PATCH bpf-next v7 09/34] bpf: refine memcg-based memory accounting for cpumap maps Roman Gushchin
2020-11-20 1:33 ` Song Liu
2020-11-19 17:37 ` [PATCH bpf-next v7 10/34] bpf: memcg-based memory accounting for cgroup storage maps Roman Gushchin
2020-11-20 1:37 ` Song Liu
2020-11-19 17:37 ` [PATCH bpf-next v7 11/34] bpf: refine memcg-based memory accounting for devmap maps Roman Gushchin
2020-11-20 1:38 ` Song Liu
2020-11-19 17:37 ` [PATCH bpf-next v7 12/34] bpf: refine memcg-based memory accounting for hashtab maps Roman Gushchin
2020-11-20 1:39 ` Song Liu
2020-11-19 17:37 ` [PATCH bpf-next v7 13/34] bpf: memcg-based memory accounting for lpm_trie maps Roman Gushchin
2020-11-20 1:39 ` Song Liu
2020-11-19 17:37 ` [PATCH bpf-next v7 14/34] bpf: memcg-based memory accounting for bpf ringbuffer Roman Gushchin
2020-11-19 17:37 ` [PATCH bpf-next v7 15/34] bpf: memcg-based memory accounting for bpf local storage maps Roman Gushchin
2020-11-20 1:44 ` Song Liu
2020-11-19 17:37 ` [PATCH bpf-next v7 16/34] bpf: refine memcg-based memory accounting for sockmap and sockhash maps Roman Gushchin
2020-11-20 1:45 ` Song Liu
2020-11-19 17:37 ` [PATCH bpf-next v7 17/34] bpf: refine memcg-based memory accounting for xskmap maps Roman Gushchin
2020-11-20 1:45 ` Song Liu
2020-11-19 17:37 ` [PATCH bpf-next v7 18/34] bpf: eliminate rlimit-based memory accounting for arraymap maps Roman Gushchin
2020-11-19 17:37 ` [PATCH bpf-next v7 19/34] bpf: eliminate rlimit-based memory accounting for bpf_struct_ops maps Roman Gushchin
2020-11-19 17:37 ` [PATCH bpf-next v7 20/34] bpf: eliminate rlimit-based memory accounting for cpumap maps Roman Gushchin
2020-11-19 17:37 ` [PATCH bpf-next v7 21/34] bpf: eliminate rlimit-based memory accounting for cgroup storage maps Roman Gushchin
2020-11-19 17:37 ` [PATCH bpf-next v7 22/34] bpf: eliminate rlimit-based memory accounting for devmap maps Roman Gushchin
2020-11-19 17:37 ` [PATCH bpf-next v7 23/34] bpf: eliminate rlimit-based memory accounting for hashtab maps Roman Gushchin
2020-11-19 17:37 ` [PATCH bpf-next v7 24/34] bpf: eliminate rlimit-based memory accounting for lpm_trie maps Roman Gushchin
2020-11-19 17:37 ` [PATCH bpf-next v7 25/34] bpf: eliminate rlimit-based memory accounting for queue_stack_maps maps Roman Gushchin
2020-11-19 17:37 ` [PATCH bpf-next v7 26/34] bpf: eliminate rlimit-based memory accounting for reuseport_array maps Roman Gushchin
2020-11-19 17:37 ` [PATCH bpf-next v7 27/34] bpf: eliminate rlimit-based memory accounting for bpf ringbuffer Roman Gushchin
2020-11-19 17:37 ` [PATCH bpf-next v7 28/34] bpf: eliminate rlimit-based memory accounting for sockmap and sockhash maps Roman Gushchin
2020-11-19 17:37 ` [PATCH bpf-next v7 29/34] bpf: eliminate rlimit-based memory accounting for stackmap maps Roman Gushchin
2020-11-19 17:37 ` [PATCH bpf-next v7 30/34] bpf: eliminate rlimit-based memory accounting for xskmap maps Roman Gushchin
2020-11-19 17:37 ` [PATCH bpf-next v7 31/34] bpf: eliminate rlimit-based memory accounting for bpf local storage maps Roman Gushchin
2020-11-19 17:37 ` [PATCH bpf-next v7 32/34] bpf: eliminate rlimit-based memory accounting infra for bpf maps Roman Gushchin
2020-11-21 2:52 ` Alexei Starovoitov
2020-11-21 2:59 ` Roman Gushchin
2020-11-19 17:37 ` [PATCH bpf-next v7 33/34] bpf: eliminate rlimit-based memory accounting for bpf progs Roman Gushchin
2020-11-19 17:37 ` [PATCH bpf-next v7 34/34] bpf: samples: do not touch RLIMIT_MEMLOCK Roman Gushchin
2020-11-23 13:30 ` [PATCH bpf-next v7 00/34] bpf: switch to memcg-based memory accounting Daniel Borkmann
2020-11-24 0:05 ` Roman Gushchin
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20201119173754.4125257-3-guro@fb.com \
--to=guro@fb.com \
--cc=akpm@linux-foundation.org \
--cc=andrii@kernel.org \
--cc=ast@kernel.org \
--cc=bpf@vger.kernel.org \
--cc=daniel@iogearbox.net \
--cc=kernel-team@fb.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=netdev@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).