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Miller" , Andrew Lunn , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Khalid Manaa , Dragos Tatulea , linux-rdma@vger.kernel.org, linux-kernel@vger.kernel.org References: <20260806065650.2444999-1-gmj@meta.com> Content-Language: en-US From: Tariq Toukan In-Reply-To: <20260806065650.2444999-1-gmj@meta.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-ClientProxiedBy: FR4P281CA0203.DEUP281.PROD.OUTLOOK.COM (2603:10a6:d10:e5::6) To SA0PR12MB7090.namprd12.prod.outlook.com (2603:10b6:806:2d5::16) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: SA0PR12MB7090:EE_|SA1PR12MB5616:EE_ X-MS-Office365-Filtering-Correlation-Id: 4581fd95-5bf0-4611-abbf-08def912feb5 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|376014|23010399003|7416014|366016|1800799024|6133799003|56012099006|10067099003|11063799006|22082099003|18002099003; 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the same approach > and behavior as sw gro). This gains code simplicity at the cost of > more computation (passing an extra skb up the stack) for small packets > that could be coalesced. > > The threshold is chosen as ETH_ZLEN + 2 * VLAN_HLEN. This is the largest > frame that may still contain minimum-frame padding (+ 2 VLAN tags), so > anything larger is safe to consider for coalesce. (We do not include > ETH_FCS_LEN in that threshold computation as netdev_fix_features() > drops NETIF_F_GRO_HW whenever NETIF_F_RXFCS is set, so retained FCS > can't reach this path.) > > Fixes: 92552d3abd32 ("net/mlx5e: HW_GRO cqe handler implementation") > Cc: stable@vger.kernel.org > Assisted-by: Claude:claude-opus-5 > Assisted-by: Meta:internal-AI-tooling > Signed-off-by: Glenn Judd > --- > Notes: > v3: Per reviewer request, redesigned to simply not coalesce > small packets. Dropping the v2 padding detection/removal. > v2: https://lore.kernel.org/netdev/20260803214412.1714151-1-gmj@meta.com/ > v1: https://lore.kernel.org/netdev/20260731185442.2778723-1-gmj@meta.com/ > > drivers/net/ethernet/mellanox/mlx5/core/en_rx.c | 5 +++++ > 1 file changed, 5 insertions(+) > > diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c b/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c > index 04af54b704d8..68b4dc49ccea 100644 > --- a/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c > +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c > @@ -2263,6 +2263,11 @@ static void mlx5e_handle_rx_cqe_mpwrq_shampo(struct mlx5e_rq *rq, struct mlx5_cq > > data_offset = wqe_offset & (page_size - 1); > page_idx = wqe_offset >> rq->mpwqe.page_shift; > + if (unlikely(cqe_bcnt <= ETH_ZLEN + 2 * VLAN_HLEN)) { > + match = false; > + flush = true; > + } > + > if (*skb && > !(match && mlx5e_hw_gro_skb_has_enough_space(*skb, data_bcnt, > page_size))) { > Reviewed-by: Tariq Toukan Thanks for your patch.