From: Shakeel Butt <shakeelb@google.com>
To: Yafang Shao <laoar.shao@gmail.com>
Cc: ast@kernel.org, daniel@iogearbox.net, andrii@kernel.org,
kafai@fb.com, songliubraving@fb.com, yhs@fb.com,
john.fastabend@gmail.com, kpsingh@kernel.org, sdf@google.com,
haoluo@google.com, jolsa@kernel.org, hannes@cmpxchg.org,
mhocko@kernel.org, roman.gushchin@linux.dev,
songmuchun@bytedance.com, akpm@linux-foundation.org,
netdev@vger.kernel.org, bpf@vger.kernel.org, linux-mm@kvack.org
Subject: Re: [PATCH bpf-next 13/15] mm, memcg: Add new helper get_obj_cgroup_from_cgroup
Date: Fri, 12 Aug 2022 16:57:56 +0000 [thread overview]
Message-ID: <20220812165756.dxaqy3go567prr5s@google.com> (raw)
In-Reply-To: <20220810151840.16394-14-laoar.shao@gmail.com>
On Wed, Aug 10, 2022 at 03:18:38PM +0000, Yafang Shao wrote:
> Introduce new helper get_obj_cgroup_from_cgroup() to get obj_cgroup from
> a specific cgroup.
Can you please add couple of lines on why you need objcg?
>
> Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
> ---
> include/linux/memcontrol.h | 1 +
> mm/memcontrol.c | 41 +++++++++++++++++++++++++++++++++++++++++
> 2 files changed, 42 insertions(+)
>
> diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
> index 2f0a611..901a921 100644
> --- a/include/linux/memcontrol.h
> +++ b/include/linux/memcontrol.h
> @@ -1713,6 +1713,7 @@ static inline void set_shrinker_bit(struct mem_cgroup *memcg,
> int __memcg_kmem_charge_page(struct page *page, gfp_t gfp, int order);
> void __memcg_kmem_uncharge_page(struct page *page, int order);
>
> +struct obj_cgroup *get_obj_cgroup_from_cgroup(struct cgroup *cgrp);
> struct obj_cgroup *get_obj_cgroup_from_current(void);
> struct obj_cgroup *get_obj_cgroup_from_page(struct page *page);
>
> diff --git a/mm/memcontrol.c b/mm/memcontrol.c
> index 618c366..762cffa 100644
> --- a/mm/memcontrol.c
> +++ b/mm/memcontrol.c
> @@ -2908,6 +2908,47 @@ static struct obj_cgroup *__get_obj_cgroup_from_memcg(struct mem_cgroup *memcg)
> return objcg;
> }
>
> +static struct obj_cgroup *get_obj_cgroup_from_memcg(struct mem_cgroup *memcg)
> +{
> + struct obj_cgroup *objcg;
> +
> + if (memcg_kmem_bypass())
> + return NULL;
> +
> + rcu_read_lock();
> + objcg = __get_obj_cgroup_from_memcg(memcg);
> + rcu_read_unlock();
> + return objcg;
> +}
> +
> +struct obj_cgroup *get_obj_cgroup_from_cgroup(struct cgroup *cgrp)
> +{
> + struct cgroup_subsys_state *css;
> + struct mem_cgroup *memcg;
> + struct obj_cgroup *objcg;
> +
> + rcu_read_lock();
> + css = rcu_dereference(cgrp->subsys[memory_cgrp_id]);
> + if (!css || !css_tryget_online(css)) {
> + rcu_read_unlock();
> + cgroup_put(cgrp);
> + return ERR_PTR(-EINVAL);
> + }
> + rcu_read_unlock();
> + cgroup_put(cgrp);
The above put seems out of place and buggy.
> +
> + memcg = mem_cgroup_from_css(css);
> + if (!memcg) {
> + css_put(css);
> + return ERR_PTR(-EINVAL);
> + }
> +
> + objcg = get_obj_cgroup_from_memcg(memcg);
> + css_put(css);
> +
> + return objcg;
> +}
> +
> __always_inline struct obj_cgroup *get_obj_cgroup_from_current(void)
> {
> struct obj_cgroup *objcg = NULL;
> --
> 1.8.3.1
>
next prev parent reply other threads:[~2022-08-12 16:58 UTC|newest]
Thread overview: 33+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-08-10 15:18 [PATCH bpf-next 00/15] bpf: Introduce selectable memcg for bpf map Yafang Shao
2022-08-10 15:18 ` [PATCH bpf-next 01/15] bpf: Remove unneeded memset in queue_stack_map creation Yafang Shao
2022-08-10 15:18 ` [PATCH bpf-next 02/15] bpf: Use bpf_map_area_free instread of kvfree Yafang Shao
2022-08-10 15:18 ` [PATCH bpf-next 03/15] bpf: Make __GFP_NOWARN consistent in bpf map creation Yafang Shao
2022-08-10 15:18 ` [PATCH bpf-next 04/15] bpf: Use bpf_map_area_alloc consistently on " Yafang Shao
2022-08-10 15:18 ` [PATCH bpf-next 05/15] bpf: Fix incorrect mem_cgroup_put Yafang Shao
2022-08-10 17:07 ` Shakeel Butt
2022-08-11 2:49 ` Yafang Shao
2022-08-11 15:47 ` Shakeel Butt
2022-08-12 0:27 ` Yafang Shao
2022-08-12 5:33 ` Muchun Song
2022-08-12 11:25 ` Yafang Shao
2022-08-11 16:48 ` Roman Gushchin
2022-08-12 0:31 ` Yafang Shao
2022-08-10 15:18 ` [PATCH bpf-next 06/15] bpf: Define bpf_map_{get,put}_memcg for !CONFIG_MEMCG_KMEM Yafang Shao
2022-08-10 15:18 ` [PATCH bpf-next 07/15] bpf: Call bpf_map_init_from_attr() immediately after map creation Yafang Shao
2022-08-10 15:18 ` [PATCH bpf-next 08/15] bpf: Save memcg in bpf_map_init_from_attr() Yafang Shao
2022-08-10 15:18 ` [PATCH bpf-next 09/15] bpf: Use scoped-based charge in bpf_map_area_alloc Yafang Shao
2022-08-10 15:18 ` [PATCH bpf-next 10/15] bpf: Introduce new helpers bpf_ringbuf_pages_{alloc,free} Yafang Shao
2022-08-10 15:18 ` [PATCH bpf-next 11/15] bpf: Use bpf_map_kzalloc in arraymap Yafang Shao
2022-08-10 15:18 ` [PATCH bpf-next 12/15] bpf: Use bpf_map_kvcalloc in bpf_local_storage Yafang Shao
2022-08-10 15:18 ` [PATCH bpf-next 13/15] mm, memcg: Add new helper get_obj_cgroup_from_cgroup Yafang Shao
2022-08-11 16:16 ` Roman Gushchin
2022-08-12 0:35 ` Yafang Shao
2022-08-12 17:40 ` Roman Gushchin
2022-08-12 23:56 ` Yafang Shao
2022-08-13 18:30 ` Roman Gushchin
2022-08-14 2:35 ` Yafang Shao
2022-08-12 16:57 ` Shakeel Butt [this message]
2022-08-13 0:07 ` Yafang Shao
2022-08-10 15:18 ` [PATCH bpf-next 14/15] bpf: Add return value for bpf_map_init_from_attr Yafang Shao
2022-08-10 15:18 ` [PATCH bpf-next 15/15] bpf: Introduce selectable memcg for bpf map Yafang Shao
2022-08-10 19:00 ` [PATCH bpf-next 00/15] " patchwork-bot+netdevbpf
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=20220812165756.dxaqy3go567prr5s@google.com \
--to=shakeelb@google.com \
--cc=akpm@linux-foundation.org \
--cc=andrii@kernel.org \
--cc=ast@kernel.org \
--cc=bpf@vger.kernel.org \
--cc=daniel@iogearbox.net \
--cc=hannes@cmpxchg.org \
--cc=haoluo@google.com \
--cc=john.fastabend@gmail.com \
--cc=jolsa@kernel.org \
--cc=kafai@fb.com \
--cc=kpsingh@kernel.org \
--cc=laoar.shao@gmail.com \
--cc=linux-mm@kvack.org \
--cc=mhocko@kernel.org \
--cc=netdev@vger.kernel.org \
--cc=roman.gushchin@linux.dev \
--cc=sdf@google.com \
--cc=songliubraving@fb.com \
--cc=songmuchun@bytedance.com \
--cc=yhs@fb.com \
/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).