From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mails.dpdk.org (mails.dpdk.org [217.70.189.124]) by inbox.dpdk.org (Postfix) with ESMTP id DC5F146BF1; Wed, 23 Jul 2025 14:30:23 +0200 (CEST) Received: from mails.dpdk.org (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id 727A540A89; Wed, 23 Jul 2025 14:30:23 +0200 (CEST) Received: from agw.arknetworks.am (agw.arknetworks.am [79.141.165.80]) by mails.dpdk.org (Postfix) with ESMTP id 38E4440653 for ; Wed, 23 Jul 2025 14:30:22 +0200 (CEST) Received: from debian (unknown [78.109.70.60]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by agw.arknetworks.am (Postfix) with ESMTPSA id A8D6AE0568; Wed, 23 Jul 2025 16:30:20 +0400 (+04) DKIM-Filter: OpenDKIM Filter v2.11.0 agw.arknetworks.am A8D6AE0568 DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arknetworks.am; s=default; t=1753273821; bh=lKuYG0jElAKEHivDAMWIr8VakbG1Uz35XeP8gi5bFDo=; h=Date:From:To:cc:Subject:In-Reply-To:References:From; b=L/207tfaZh2QYbXayq7TPhb9rPw0v9hDqX4mq1b4WQ7jQTlpvi0yrICba8PpTu/YZ 012ZdXEKcDALQdSj9r60iTpqKEc4HaWkpPW7shdcYQK4Lo5htvFpzKvJX+2WkSE67f rM++6ZGNUi81Cj7IgoE5qHBSMTDBuWiKCf5sRTUVEvvM1d2jiTmm0TpF15sbO2VMwg SSjgKe+sy3VYm4vHJP74so/gv35xzi2hg2iWWuHjTNad+KFZoyVzQOMGMRkv/TrybI Qh24LMURfT0b0PZhN8sHYumXbeTu/Vssz0bJ5wOBVNi3CrA9gNUupb2T1/eafa2zzq 2ePXjL+3NO/eQ== Date: Wed, 23 Jul 2025 16:30:19 +0400 (+04) From: Ivan Malov To: Shivaji Kant cc: Ciara Loftus , Maryam Tahhan , dev@dpdk.org, Joshua Washington Subject: Re: [PATCH] net/af_xdp: enable AF_XDP program attachment mode In-Reply-To: <20250723074249.3264675-1-shivajikant@google.com> Message-ID: References: <20250723074249.3264675-1-shivajikant@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Hi Shivaji, (please see below) On Wed, 23 Jul 2025, Shivaji Kant wrote: > Currently, the AF_XDP PMD attaches its XDP program using a fixed > set of flags,defaulting to `XDP_FLAGS_UPDATE_IF_NOEXIST`. This lacks > flexibility for users who might need to explicitly control the XDP > mode based on their specific hardware capabilities or performance > requirements. > > This patch introduces a new vdev argument, `mode`, for the `net_af_xdp` > PMD. This argument allows users to explicitly specify the desired > XDP program attachment mode: > `drv` (XDP_FLAGS_DRV_MODE), > `skb` (XDP_FLAGS_SKB_MODE), > `hw` (XDP_FLAGS_HW_MODE). > (If needed more can be added) > > This change provides greater control and flexibility for users to > fine-tune AF_XDP behavior, enabling them to leverage native driver > or hardware offload capabilities when available, or fall back to > generic SKB mode for broader compatibility. > > Signed-off-by: Shivaji Kant > --- > drivers/net/af_xdp/rte_eth_af_xdp.c | 61 +++++++++++++++++++++++++---- > 1 file changed, 54 insertions(+), 7 deletions(-) > > diff --git a/drivers/net/af_xdp/rte_eth_af_xdp.c b/drivers/net/af_xdp/rte_eth_af_xdp.c > index 5f65850a27..e39f2b4935 100644 > --- a/drivers/net/af_xdp/rte_eth_af_xdp.c > +++ b/drivers/net/af_xdp/rte_eth_af_xdp.c > @@ -104,6 +104,8 @@ RTE_LOG_REGISTER_DEFAULT(af_xdp_logtype, NOTICE); > > static int afxdp_dev_count; > > +static __u32 mode_flag = XDP_FLAGS_UPDATE_IF_NOEXIST; If one seeks to add a per-device argument, then why is this static/driver-wide? This belongs in 'struct pmd_internals'. Thank you. > + > /* Message header to synchronize fds via IPC */ > struct ipc_hdr { > char port_name[RTE_DEV_NAME_MAX_LEN]; > @@ -198,6 +200,26 @@ struct pmd_process_private { > #define ETH_AF_XDP_USE_CNI_ARG "use_cni" > #define ETH_AF_XDP_USE_PINNED_MAP_ARG "use_pinned_map" > #define ETH_AF_XDP_DP_PATH_ARG "dp_path" > +#define ETH_AF_XDP_MODE_ARG "mode" > + > +/* Define different modes for af_xdp prog to attach */ > +#define ETH_AF_XDP_DRV_MODE_ARG "drv" > +#define ETH_AF_XDP_SKB_MODE_ARG "skb" > +#define ETH_AF_XDP_HW_MODE_ARG "hw" > +#define ETH_AF_XDP_NUM_MODE_ARG 3 > + > +static const char * const mode_arguments[] = { > + ETH_AF_XDP_DRV_MODE_ARG, > + ETH_AF_XDP_SKB_MODE_ARG, > + ETH_AF_XDP_HW_MODE_ARG, > + NULL > +}; > + > +static const unsigned int mode_flags[] = { > + XDP_FLAGS_DRV_MODE, > + XDP_FLAGS_SKB_MODE, > + XDP_FLAGS_HW_MODE > +}; > > static const char * const valid_arguments[] = { > ETH_AF_XDP_IFACE_ARG, > @@ -210,6 +232,7 @@ static const char * const valid_arguments[] = { > ETH_AF_XDP_USE_CNI_ARG, > ETH_AF_XDP_USE_PINNED_MAP_ARG, > ETH_AF_XDP_DP_PATH_ARG, > + ETH_AF_XDP_MODE_ARG, > NULL > }; > > @@ -950,14 +973,14 @@ remove_xdp_program(struct pmd_internals *internals) > uint32_t curr_prog_id = 0; > int ret; > > - ret = bpf_xdp_query_id(internals->if_index, XDP_FLAGS_UPDATE_IF_NOEXIST, > + ret = bpf_xdp_query_id(internals->if_index, mode_flag, > &curr_prog_id); > if (ret != 0) { > AF_XDP_LOG_LINE(ERR, "bpf_xdp_query_id failed"); > return ret; > } > > - ret = bpf_xdp_detach(internals->if_index, XDP_FLAGS_UPDATE_IF_NOEXIST, > + ret = bpf_xdp_detach(internals->if_index, mode_flag, > NULL); > if (ret != 0) > AF_XDP_LOG_LINE(ERR, "bpf_xdp_detach failed"); > @@ -978,14 +1001,14 @@ remove_xdp_program(struct pmd_internals *internals) > int ret; > > ret = bpf_get_link_xdp_id(internals->if_index, &curr_prog_id, > - XDP_FLAGS_UPDATE_IF_NOEXIST); > + mode_flag); > if (ret != 0) { > AF_XDP_LOG_LINE(ERR, "bpf_get_link_xdp_id failed"); > return ret; > } > > ret = bpf_set_link_xdp_fd(internals->if_index, -1, > - XDP_FLAGS_UPDATE_IF_NOEXIST); > + mode_flag); > if (ret != 0) > AF_XDP_LOG_LINE(ERR, "bpf_set_link_xdp_fd failed"); > return ret; > @@ -1328,7 +1351,7 @@ load_custom_xdp_prog(const char *prog_path, int if_index, struct bpf_map **map) > > /* Link the program with the given network device */ > ret = link_xdp_prog_with_dev(if_index, prog_fd, > - XDP_FLAGS_UPDATE_IF_NOEXIST); > + mode_flag); > if (ret) { > AF_XDP_LOG_LINE(ERR, "Failed to set prog fd %d on interface", > prog_fd); > @@ -1679,7 +1702,7 @@ xsk_configure(struct pmd_internals *internals, struct pkt_rx_queue *rxq, > cfg.rx_size = ring_size; > cfg.tx_size = ring_size; > cfg.libbpf_flags = 0; > - cfg.xdp_flags = XDP_FLAGS_UPDATE_IF_NOEXIST; > + cfg.xdp_flags = mode_flag; > cfg.bind_flags = 0; > > /* Force AF_XDP socket into copy mode when users want it */ > @@ -2017,6 +2040,25 @@ parse_name_arg(const char *key __rte_unused, > return 0; > } > > +/** parse name argument */ > +static int > +parse_mode_arg(const char *key __rte_unused, > + const char *value, void *extra_args) > +{ > + unsigned int *mode = extra_args; > + unsigned int i; > + > + for (i = 0; i < ETH_AF_XDP_NUM_MODE_ARG; i++) { > + if (strcmp(value, mode_arguments[i]) == 0) { > + *mode |= mode_flags[i]; > + return 0; > + } > + } > + > + AF_XDP_LOG_LINE(ERR, "Invalid af_xdp mode, choose correct mode to attach af_xdp program."); > + return -EINVAL; > +} > + > /** parse xdp prog argument */ > static int > parse_prog_arg(const char *key __rte_unused, > @@ -2147,6 +2189,10 @@ parse_parameters(struct rte_kvargs *kvlist, char *if_name, int *start_queue, > > ret = rte_kvargs_process(kvlist, ETH_AF_XDP_DP_PATH_ARG, > &parse_prog_arg, dp_path); > + > + ret = rte_kvargs_process(kvlist, ETH_AF_XDP_MODE_ARG, > + &parse_mode_arg, &mode_flag); > + > if (ret < 0) > goto free_kvlist; > > @@ -2587,4 +2633,5 @@ RTE_PMD_REGISTER_PARAM_STRING(net_af_xdp, > "force_copy= " > "use_cni= " > "use_pinned_map= " > - "dp_path= "); > + "dp_path= " > + "mode= "); > -- > 2.50.0.727.gbf7dc18ff4-goog > >