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Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Kuniyuki Iwashima , Willem de Bruijn , Neal Cardwell , David Ahern , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Stanislav Fomichev , Mina Almasry , Bobby Eshleman Subject: Re: [PATCH net-next v3 0/2] net: devmem: improve cpu cost of RX token management Message-ID: References: <20250926-scratch-bobbyeshleman-devmem-tcp-token-upstream-v3-0-084b46bda88f@meta.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Fri, Sep 26, 2025 at 04:55:01PM +0100, Simon Horman wrote: > On Fri, Sep 26, 2025 at 08:02:52AM -0700, Bobby Eshleman wrote: > > This series improves the CPU cost of RX token management by replacing > > the xarray allocator with an niov array and a uref field in niov. > > > > Improvement is ~5% per RX user thread. > > > > Two other approaches were tested, but with no improvement. Namely, 1) > > using a hashmap for tokens and 2) keeping an xarray of atomic counters > > but using RCU so that the hotpath could be mostly lockless. Neither of > > these approaches proved better than the simple array in terms of CPU. > > > > Running with a NCCL workload is still TODO, but I will follow up on this > > thread with those results when done. > > > > Signed-off-by: Bobby Eshleman > > Hi Bobby, > > Unfortunately this patchset doesn't apply cleanly to net-next. > So you'll need to rebase and repost at some point. > > -- > pw-bot: changes-requested Got it, just resent and added this check to my automation, thanks! Best, Bobby