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McKenney" , Paul Gortmaker , Johannes Weiner , Marcelo Tosatti , Phil Auld , Zefan Li , Daniel Bristot de Oliveira , Nicolas Saenz Julienne , rcu@vger.kernel.org Subject: Re: [RFC PATCH 4/4] cpuset: Support RCU-NOCB toggle on v2 root partitions Message-ID: <20220527083018.n43nc73vuuzm5ixo@localhost.localdomain> References: <20220525221055.1152307-1-frederic@kernel.org> <20220525221055.1152307-5-frederic@kernel.org> <20220526225141.GA1214445@lothringen> <9e44bb00-955a-dbc6-a863-be649e0c701f@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, On 26/05/22 14:37, Tejun Heo wrote: > On Thu, May 26, 2022 at 08:28:43PM -0400, Waiman Long wrote: > > I am thinking along the line that it will not be hierarchical. However, > > cpuset can be useful if we want to have multiple isolated partitions > > underneath the top cpuset with different isolation attributes, but no more > > sub-isolated partition with sub-attributes underneath them. IOW, we can only > > set them at the first level under top_cpuset. Will that be useful? > > At that point, I'd just prefer to have it under /proc or /sys. FWIW, I was under the impression that this would nicely fit along the side of other feaures towards implenting dynamic isolation of CPUs (say https://lore.kernel.org/lkml/20220510153413.400020-1-longman@redhat.com/ for example). Wouldn't be awkward to have to poke different places to achieve isolation at runtime? Also, I wonder if a proc/sys interface might be problematic for certain middleware that is substantially based on using cgroups. I'll try to ask around. :) Best, Juri