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[213.151.95.130]) by smtp.gmail.com with ESMTPSA id n12sm7280468wmd.1.2019.12.04.07.32.25 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 04 Dec 2019 07:32:25 -0800 (PST) Date: Wed, 4 Dec 2019 16:32:25 +0100 From: Michal Hocko To: Christopher Lameter Cc: LKML , linux-mm@kvack.org Subject: Re: SLUB: purpose of sysfs events on cache creation/removal Message-ID: <20191204153225.GM25242@dhcp22.suse.cz> References: <20191126121901.GE20912@dhcp22.suse.cz> <20191126165420.GL20912@dhcp22.suse.cz> <20191127162400.GT20912@dhcp22.suse.cz> <20191127174317.GD26807@dhcp22.suse.cz> <20191204132812.GF25242@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed 04-12-19 15:25:43, Cristopher Lameter wrote: > On Wed, 4 Dec 2019, Michal Hocko wrote: > > > > > Just drop the events may be best. Then we know if someone is using it. > > > > > > I would be worried that a lack of events might be surprising and a > > > potential userspace wouldn't know that something has changed. > > > > It would be great to land with some decision here. > > Drop the events. These are internal kernel structures and supporting > notifiers to userspace is a bit unusual. As I've said I believe it is quite risky. But if you as a maintainer believe this is the right thing to do I will not object. Care to send a patch? -- Michal Hocko SUSE Labs