Message-ID: <206e47d2-64da-babe-17d1-da846fbba959@suse.cz>
Date:   Tue, 16 Nov 2021 18:27:21 +0100
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Subject: Re: [PATCH] mm: memcontrol: make cgroup_memory_nokmem static
Content-Language: en-US
To:     Muchun Song <songmuchun@bytedance.com>, akpm@linux-foundation.org,
        hannes@cmpxchg.org, mhocko@kernel.org, vdavydov.dev@gmail.com
Cc:     linux-mm@kvack.org, linux-kernel@vger.kernel.org
References: <20211109065418.21693-1-songmuchun@bytedance.com>
From:   Vlastimil Babka <vbabka@suse.cz>
In-Reply-To: <20211109065418.21693-1-songmuchun@bytedance.com>
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Precedence: bulk

On 11/9/21 07:54, Muchun Song wrote:
> The commit 494c1dfe855e ("mm: memcg/slab: create a new set of kmalloc-cg-<n>
> caches") makes cgroup_memory_nokmem global, however, it is unnecessary
> because there is already a function mem_cgroup_kmem_disabled() which
> exports it.
> 
> Just make it static and replace it with mem_cgroup_kmem_disabled()
> in mm/slab_common.c.
> 
> Signed-off-by: Muchun Song <songmuchun@bytedance.com>

Acked-by: Vlastimil Babka <vbabka@suse.cz>

> ---
>  mm/internal.h    | 5 -----
>  mm/memcontrol.c  | 2 +-
>  mm/slab_common.c | 2 +-
>  3 files changed, 2 insertions(+), 7 deletions(-)
> 
> diff --git a/mm/internal.h b/mm/internal.h
> index 18256e32a14c..ad15251d7a3c 100644
> --- a/mm/internal.h
> +++ b/mm/internal.h
> @@ -137,11 +137,6 @@ extern void putback_lru_page(struct page *page);
>  extern pmd_t *mm_find_pmd(struct mm_struct *mm, unsigned long address);
>  
>  /*
> - * in mm/memcontrol.c:
> - */
> -extern bool cgroup_memory_nokmem;
> -
> -/*
>   * in mm/page_alloc.c
>   */
>  
> diff --git a/mm/memcontrol.c b/mm/memcontrol.c
> index 8f1d9c028897..89fc3ca65b2d 100644
> --- a/mm/memcontrol.c
> +++ b/mm/memcontrol.c
> @@ -84,7 +84,7 @@ EXPORT_PER_CPU_SYMBOL_GPL(int_active_memcg);
>  static bool cgroup_memory_nosocket __ro_after_init;
>  
>  /* Kernel memory accounting disabled? */
> -bool cgroup_memory_nokmem __ro_after_init;
> +static bool cgroup_memory_nokmem __ro_after_init;
>  
>  /* Whether the swap controller is active */
>  #ifdef CONFIG_MEMCG_SWAP
> diff --git a/mm/slab_common.c b/mm/slab_common.c
> index e5d080a93009..d05203a11201 100644
> --- a/mm/slab_common.c
> +++ b/mm/slab_common.c
> @@ -849,7 +849,7 @@ new_kmalloc_cache(int idx, enum kmalloc_cache_type type, slab_flags_t flags)
>  	if (type == KMALLOC_RECLAIM) {
>  		flags |= SLAB_RECLAIM_ACCOUNT;
>  	} else if (IS_ENABLED(CONFIG_MEMCG_KMEM) && (type == KMALLOC_CGROUP)) {
> -		if (cgroup_memory_nokmem) {
> +		if (mem_cgroup_kmem_disabled()) {
>  			kmalloc_caches[type][idx] = kmalloc_caches[KMALLOC_NORMAL][idx];
>  			return;
>  		}
>