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charset=us-ascii Content-Disposition: inline In-Reply-To: <20201214223722.232537-3-shy828301@gmail.com> X-Bogosity: Ham, tests=bogofilter, spamicity=0.005165, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Mon, Dec 14, 2020 at 02:37:15PM -0800, Yang Shi wrote: > Since memcg_shrinker_map_size just can be changd under holding shrinker_rwsem > exclusively, the read side can be protected by holding read lock, so it sounds > superfluous to have a dedicated mutex. This should not exacerbate the contention > to shrinker_rwsem since just one read side critical section is added. > > Signed-off-by: Yang Shi Acked-by: Johannes Weiner Thanks Yang, this is a step in the right direction. It would still be nice to also drop memcg_shrinker_map_size and (trivially) derive that value from shrinker_nr_max where necessary. It is duplicate state.