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Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Maarten Lankhorst , Maxime Ripard , Natalie Vock , Tejun Heo , Oscar Salvador , Jingxiang Zeng , Michal Hocko , cgroups@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org Subject: Re: [PATCH v2 0/3] mm: page_counter: move hierarchical protection out of struct page_counter Message-ID: References: <20260909-descriptive-name-v2-0-d7dd7c099049@tencent.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="ozrropszbqjorccy" Content-Disposition: inline In-Reply-To: <20260909-descriptive-name-v2-0-d7dd7c099049@tencent.com> --ozrropszbqjorccy Content-Type: text/plain; protected-headers=v1; charset=us-ascii Content-Disposition: inline Subject: Re: [PATCH v2 0/3] mm: page_counter: move hierarchical protection out of struct page_counter MIME-Version: 1.0 Hi. On Wed, Sep 09, 2026 at 05:44:18PM +0800, linuszeng via B4 Relay wrote: > No functional change is intended: protection semantics and the cgroup > v1/v2 behaviour are preserved. It is not clear from the description what is the intention then :-) Do you have any measurements that the reduced cache footprint changes performance for setups without protection? And what is the positive impact on protected scenarios where the counters are in (possibly) different cacheline and one indirection further? Thanks, Michal --ozrropszbqjorccy Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iJEEABYKADkWIQRCE24Fn/AcRjnLivR+PQLnlNv4CAUCaqQbfBsUgAAAAAAEAA5t YW51MiwyLjUrMS4xMiwyLDIACgkQfj0C55Tb+AjHdwEA9eabDSoks6Xn+ni3bc0I AP32Ul+BBWTmz5HMyoTjovoA/2JJSh5lKBEsuu0fwEMrZGzX9XiTI5mG6CHzszPG ztkH =VS/g -----END PGP SIGNATURE----- --ozrropszbqjorccy--