From mboxrd@z Thu Jan 1 00:00:00 1970 From: Michal Hocko Subject: Re: [PATCH] mm: Make mem_cgroup_id_get_many dependent on MMU and MEMCG_SWAP Date: Wed, 4 Mar 2020 17:53:36 +0100 Message-ID: <20200304165336.GO16139@dhcp22.suse.cz> References: <20200304142348.48167-1-vincenzo.frascino@arm.com> Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Return-path: Content-Disposition: inline In-Reply-To: <20200304142348.48167-1-vincenzo.frascino-5wv7dgnIgG8@public.gmane.org> Sender: cgroups-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: Content-Type: text/plain; charset="utf-8" To: Vincenzo Frascino Cc: cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-mm-Bw31MaZKKs3YtjvyW6yDsg@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Johannes Weiner , Vladimir Davydov , Andrew Morton On Wed 04-03-20 14:23:48, Vincenzo Frascino wrote: > mem_cgroup_id_get_many() is currently used only when MMU or MEMCG_SWAP > configuration options are enabled. Having them disabled triggers the > following warning at compile time: > > linux/mm/memcontrol.c:4797:13: warning: ‘mem_cgroup_id_get_many’ defined > but not used [-Wunused-function] > static void mem_cgroup_id_get_many(struct mem_cgroup *memcg, unsigned > int n) > > Make mem_cgroup_id_get_many() dependent on MMU and MEMCG_SWAP to address > the issue. A similar patch has been proposed recently http://lkml.kernel.org/r/87fthjh2ib.wl-kuninori.morimoto.gx-zM6kxYcvzFDowKkBSvOlow@public.gmane.org The conclusion was that the warning is not really worth adding code. > Cc: Johannes Weiner > Cc: Michal Hocko > Cc: Vladimir Davydov > Cc: Andrew Morton > Signed-off-by: Vincenzo Frascino > --- > mm/memcontrol.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/mm/memcontrol.c b/mm/memcontrol.c > index d09776cd6e10..628cebeb4bdd 100644 > --- a/mm/memcontrol.c > +++ b/mm/memcontrol.c > @@ -4794,10 +4794,12 @@ static void mem_cgroup_id_remove(struct mem_cgroup *memcg) > } > } > > +#if defined(CONFIG_MEMCG_SWAP) || defined(CONFIG_MMU) > static void mem_cgroup_id_get_many(struct mem_cgroup *memcg, unsigned int n) > { > refcount_add(n, &memcg->id.ref); > } > +#endif > > static void mem_cgroup_id_put_many(struct mem_cgroup *memcg, unsigned int n) > { > -- > 2.25.1 -- Michal Hocko SUSE Labs