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Miller" , Jakub Kicinski , Paolo Abeni , Jamal Hadi Salim , Cong Wang , Jiri Pirko , netdev@vger.kernel.org, eric.dumazet@gmail.com, cake@lists.bufferbloat.net Subject: Re: [PATCH net-next 02/14] net_sched: cake: implement lockless cake_dump() In-Reply-To: <20240417083549.GA3846178@kernel.org> References: <20240415132054.3822230-1-edumazet@google.com> <20240415132054.3822230-3-edumazet@google.com> <20240417083549.GA3846178@kernel.org> X-Clacks-Overhead: GNU Terry Pratchett Date: Wed, 17 Apr 2024 14:25:08 +0200 Message-ID: <87cyqouqfv.fsf@toke.dk> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Simon Horman writes: > + Toke H=C3=B8iland-J=C3=B8rgensen > cake@lists.bufferbloat.net Thanks! > On Mon, Apr 15, 2024 at 01:20:42PM +0000, Eric Dumazet wrote: >> Instead of relying on RTNL, cake_dump() can use READ_ONCE() >> annotations, paired with WRITE_ONCE() ones in cake_change(). >>=20 >> Signed-off-by: Eric Dumazet Just to be sure I understand this correctly: the idea is that with READ/WRITE_ONCE annotations, we can dump the qdisc options without taking the RTNL lock. This means that a dump not be consistent across a concurrent reconfig that changes multiple parameters, but each parameter will be either the new or the old value. Right? -Toke