From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alex Shi Subject: Re: [PATCH v18 15/32] mm/lru: move lock into lru_note_cost Date: Tue, 22 Sep 2020 11:39:05 +0800 Message-ID: <323ae796-a547-3ac3-b4fd-68a4ac180690@linux.alibaba.com> References: <1598273705-69124-1-git-send-email-alex.shi@linux.alibaba.com> <1598273705-69124-16-git-send-email-alex.shi@linux.alibaba.com> Mime-Version: 1.0 Content-Transfer-Encoding: quoted-printable Return-path: In-Reply-To: List-ID: Content-Type: text/plain; charset="iso-8859-1" To: Hugh Dickins Cc: akpm-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org, mgorman-3eNAlZScCAx27rWaFMvyedHuzzzSOjJt@public.gmane.org, tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, khlebnikov-XoJtRXgx1JseBXzfvpsJ4g@public.gmane.org, daniel.m.jordan-QHcLZuEGTsvQT0dZR+AlfA@public.gmane.org, willy-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org, hannes-druUgvl0LCNAfugRpC6u6w@public.gmane.org, lkp-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org, linux-mm-Bw31MaZKKs3YtjvyW6yDsg@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, shakeelb-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org, iamjoonsoo.kim-Hm3cg6mZ9cc@public.gmane.org, richard.weiyang-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, kirill-oKw7cIdHH8eLwutG50LtGA@public.gmane.org, alexander.duyck-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, rong.a.chen-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org, mhocko-IBi9RG/b67k@public.gmane.org, vdavydov.dev-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, shy828301-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org =D4=DA 2020/9/22 =C9=CF=CE=E76:03, Hugh Dickins =D0=B4=B5=C0: >> Acked-by: Hugh Dickins >> >> In your lruv19 github tree, you have merged 14/32 into this one: thanks. > Grr, I've only just started, and already missed some of my notes. >=20 > I wanted to point out that this patch does introduce an extra unlock+lock > in shrink_inactive_list(), even in a !CONFIG_MEMCG build. I think you've > done the right thing for now, keeping it simple, and maybe nobody will > notice the extra overhead; but I expect us to replace lru_note_cost() > by lru_note_cost_unlock_irq() later on, expecting the caller to do the > initial lock_irq(). >=20 > lru_note_cost_page() looks redundant to me, but you're right not to > delete it here, unless Johannes asks you to add that in: that's his > business, and it may be dependent on the XXX at its callsite. >=20 Thanks for comments! And got your point. so I will leave this patch alone. Thanks!