From patchwork Tue Nov 23 16:39:31 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alexander Lobakin X-Patchwork-Id: 12634675 X-Patchwork-Delegate: kuba@kernel.org Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 005A9C433FE for ; Tue, 23 Nov 2021 16:41:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233787AbhKWQoi (ORCPT ); Tue, 23 Nov 2021 11:44:38 -0500 Received: from mga17.intel.com ([192.55.52.151]:39357 "EHLO mga17.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233864AbhKWQoc (ORCPT ); Tue, 23 Nov 2021 11:44:32 -0500 X-IronPort-AV: E=McAfee;i="6200,9189,10177"; a="215767227" X-IronPort-AV: E=Sophos;i="5.87,258,1631602800"; d="scan'208";a="215767227" Received: from orsmga002.jf.intel.com ([10.7.209.21]) by fmsmga107.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 23 Nov 2021 08:41:23 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.87,258,1631602800"; d="scan'208";a="474813269" Received: from irvmail001.ir.intel.com ([10.43.11.63]) by orsmga002.jf.intel.com with ESMTP; 23 Nov 2021 08:41:12 -0800 Received: from newjersey.igk.intel.com (newjersey.igk.intel.com [10.102.20.203]) by irvmail001.ir.intel.com (8.14.3/8.13.6/MailSET/Hub) with ESMTP id 1ANGf4We016784; Tue, 23 Nov 2021 16:41:09 GMT From: Alexander Lobakin To: "David S. Miller" , Jakub Kicinski Cc: Alexander Lobakin , Jesse Brandeburg , Michal Swiatkowski , Maciej Fijalkowski , Jonathan Corbet , Shay Agroskin , Arthur Kiyanovski , David Arinzon , Noam Dagan , Saeed Bishara , Ioana Ciornei , Claudiu Manoil , Tony Nguyen , Thomas Petazzoni , Marcin Wojtas , Russell King , Saeed Mahameed , Leon Romanovsky , Alexei Starovoitov , Daniel Borkmann , Jesper Dangaard Brouer , =?utf-8?q?Toke_H=C3=B8iland-J?= =?utf-8?q?=C3=B8rgensen?= , John Fastabend , Edward Cree , Martin Habets , "Michael S. Tsirkin" , Jason Wang , Andrii Nakryiko , Martin KaFai Lau , Song Liu , Yonghong Song , KP Singh , Lorenzo Bianconi , Yajun Deng , Sergey Ryazanov , David Ahern , Andrei Vagin , Johannes Berg , Vladimir Oltean , Cong Wang , netdev@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-rdma@vger.kernel.org, bpf@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v2 net-next 02/26] xdp: provide common driver helpers for implementing XDP stats Date: Tue, 23 Nov 2021 17:39:31 +0100 Message-Id: <20211123163955.154512-3-alexandr.lobakin@intel.com> X-Mailer: git-send-email 2.33.1 In-Reply-To: <20211123163955.154512-1-alexandr.lobakin@intel.com> References: <20211123163955.154512-1-alexandr.lobakin@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org Add several shorthands to reduce driver boilerplates and unify storing and accessing generic XDP statistics in the drivers. If the driver has one of xdp_{rx,tx}_drv_stats embedded into a ring structure, it can reuse pretty much everything, but needs to implement its own .ndo_xdp_stats() and .ndo_xdp_stats_nch() if needed. If the driver stores a separate array of xdp_drv_stats, it can then export it as net_device::xstats, implement only .ndo_xdp_stats_nch() and wire up xdp_get_drv_stats_generic() as .ndo_xdp_stats(). Both XDP and XSK blocks of xdp_drv_stats are cacheline-aligned to avoid false-sharing, only extremely unlikely 'aborted' and 'invalid' falls out of a 64-byte CL. xdp_rx_drv_stats_local is provided to put it on stack and collect the stats on hotpath, with accessing a real container and its atomic/seqcount sync points just once when exiting Rx NAPI polling. Signed-off-by: Alexander Lobakin Reviewed-by: Jesse Brandeburg Reviewed-by: Michal Swiatkowski Reviewed-by: Maciej Fijalkowski --- include/linux/netdevice.h | 1 + include/net/xdp.h | 162 ++++++++++++++++++++++++++++++++++++++ net/core/xdp.c | 124 +++++++++++++++++++++++++++++ 3 files changed, 287 insertions(+) -- 2.33.1 diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 058a00c2d19a..728c650d290e 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -2225,6 +2225,7 @@ struct net_device { struct pcpu_lstats __percpu *lstats; struct pcpu_sw_netstats __percpu *tstats; struct pcpu_dstats __percpu *dstats; + struct xdp_drv_stats /* per-channel */ *xstats; }; #if IS_ENABLED(CONFIG_GARP) diff --git a/include/net/xdp.h b/include/net/xdp.h index 447f9b1578f3..e4f06a34d462 100644 --- a/include/net/xdp.h +++ b/include/net/xdp.h @@ -7,6 +7,7 @@ #define __LINUX_NET_XDP_H__ #include /* skb_shared_info */ +#include /* u64_stats_* */ /** * DOC: XDP RX-queue information @@ -292,4 +293,165 @@ void xdp_attachment_setup(struct xdp_attachment_info *info, #define DEV_MAP_BULK_SIZE XDP_BULK_QUEUE_SIZE +/* Suggested XDP/XSK driver stats, mirror &ifla_xdp_stats except + * for generic errors, refer to its documentation for the details. + * The intended usage is to either have them as a standalone array + * of xdp_drv_stats, or embed &xdp_{rx,tx}_drv_stats into a ring + * structure. Having separate XDP and XSK counters is recommended. + */ + +struct ifla_xdp_stats; + +struct xdp_rx_drv_stats { + struct u64_stats_sync syncp; + u64_stats_t packets; + u64_stats_t bytes; + u64_stats_t pass; + u64_stats_t drop; + u64_stats_t redirect; + u64_stats_t tx; + u64_stats_t redirect_errors; + u64_stats_t tx_errors; + u64_stats_t aborted; + u64_stats_t invalid; +}; + +struct xdp_tx_drv_stats { + struct u64_stats_sync syncp; + u64_stats_t packets; + u64_stats_t bytes; + u64_stats_t errors; + u64_stats_t full; +}; + +struct xdp_drv_stats { + struct xdp_rx_drv_stats xdp_rx; + struct xdp_tx_drv_stats xdp_tx; + struct xdp_rx_drv_stats xsk_rx ____cacheline_aligned; + struct xdp_tx_drv_stats xsk_tx; +} ____cacheline_aligned; + +/* Shortened copy of Rx stats to put on stack */ +struct xdp_rx_drv_stats_local { + u32 bytes; + u32 packets; + u32 pass; + u32 drop; + u32 tx; + u32 tx_errors; + u32 redirect; + u32 redirect_errors; + u32 aborted; + u32 invalid; +}; + +#define xdp_init_rx_drv_stats(rstats) u64_stats_init(&(rstats)->syncp) +#define xdp_init_tx_drv_stats(tstats) u64_stats_init(&(tstats)->syncp) + +/** + * xdp_init_drv_stats - initialize driver XDP stats + * @xdp_stats: driver container if it uses generic xdp_drv_stats + * + * Initializes atomic/seqcount sync points inside the containers. + */ +static inline void xdp_init_drv_stats(struct xdp_drv_stats *xdp_stats) +{ + xdp_init_rx_drv_stats(&xdp_stats->xdp_rx); + xdp_init_tx_drv_stats(&xdp_stats->xdp_tx); + xdp_init_rx_drv_stats(&xdp_stats->xsk_rx); + xdp_init_tx_drv_stats(&xdp_stats->xsk_tx); +} + +/** + * xdp_update_rx_drv_stats - update driver XDP stats + * @rstats: target driver container + * @lrstats: filled onstack structure + * + * Fetches Rx path XDP statistics from the onstack structure to the + * driver container, respecting atomic/seqcount synchronization. + * Typical usage is to call it at the end of Rx NAPI polling. + */ +static inline void +xdp_update_rx_drv_stats(struct xdp_rx_drv_stats *rstats, + const struct xdp_rx_drv_stats_local *lrstats) +{ + if (!lrstats->packets) + return; + + u64_stats_update_begin(&rstats->syncp); + u64_stats_add(&rstats->packets, lrstats->packets); + u64_stats_add(&rstats->bytes, lrstats->bytes); + u64_stats_add(&rstats->pass, lrstats->pass); + u64_stats_add(&rstats->drop, lrstats->drop); + u64_stats_add(&rstats->redirect, lrstats->redirect); + u64_stats_add(&rstats->tx, lrstats->tx); + u64_stats_add(&rstats->redirect_errors, lrstats->redirect_errors); + u64_stats_add(&rstats->tx_errors, lrstats->tx_errors); + u64_stats_add(&rstats->aborted, lrstats->aborted); + u64_stats_add(&rstats->invalid, lrstats->invalid); + u64_stats_update_end(&rstats->syncp); +} + +/** + * xdp_update_tx_drv_stats - update driver XDP stats + * @tstats: target driver container + * @packets: onstack packet counter + * @bytes: onstack octete counter + * + * Adds onstack packet/byte Tx XDP counter values from the current session + * to the driver container. Typical usage is to call it on completion path / + * Tx NAPI polling. + */ +static inline void xdp_update_tx_drv_stats(struct xdp_tx_drv_stats *tstats, + u32 packets, u32 bytes) +{ + if (!packets) + return; + + u64_stats_update_begin(&tstats->syncp); + u64_stats_add(&tstats->packets, packets); + u64_stats_add(&tstats->bytes, bytes); + u64_stats_update_end(&tstats->syncp); +} + +/** + * xdp_update_tx_drv_err - update driver Tx XDP errors counter + * @tstats: target driver container + * @num: onstack error counter / number of non-xmitted frames + * + * Adds onstack error Tx XDP counter value from the current session + * to the driver container. Typical usage is to call it at on error + * path of .ndo_xdp_xmit() / XSK zerocopy xmit. + */ +static inline void xdp_update_tx_drv_err(struct xdp_tx_drv_stats *tstats, + u32 num) +{ + u64_stats_update_begin(&tstats->syncp); + u64_stats_add(&tstats->errors, num); + u64_stats_update_end(&tstats->syncp); +} + +/** + * xdp_update_tx_drv_full - update driver Tx XDP ring full counter + * @tstats: target driver container + * + * Adds onstack error Tx XDP counter value from the current session + * to the driver container. Typical usage is to call it at in case + * of no free descs available on a ring in .ndo_xdp_xmit() / XSK + * zerocopy xmit. + */ +static inline void xdp_update_tx_drv_full(struct xdp_tx_drv_stats *tstats) +{ + u64_stats_update_begin(&tstats->syncp); + u64_stats_inc(&tstats->full); + u64_stats_update_end(&tstats->syncp); +} + +void xdp_fetch_rx_drv_stats(struct ifla_xdp_stats *if_stats, + const struct xdp_rx_drv_stats *rstats); +void xdp_fetch_tx_drv_stats(struct ifla_xdp_stats *if_stats, + const struct xdp_tx_drv_stats *tstats); +int xdp_get_drv_stats_generic(const struct net_device *dev, u32 attr_id, + void *attr_data); + #endif /* __LINUX_NET_XDP_H__ */ diff --git a/net/core/xdp.c b/net/core/xdp.c index 5ddc29f29bad..24980207303c 100644 --- a/net/core/xdp.c +++ b/net/core/xdp.c @@ -611,3 +611,127 @@ struct xdp_frame *xdpf_clone(struct xdp_frame *xdpf) return nxdpf; } + +/** + * xdp_fetch_rx_drv_stats - helper for implementing .ndo_get_xdp_stats() + * @if_stats: target container passed from rtnetlink core + * @rstats: driver container if it uses generic xdp_rx_drv_stats + * + * Fetches Rx path XDP statistics from a suggested driver structure to + * the one used by rtnetlink, respecting atomic/seqcount synchronization. + */ +void xdp_fetch_rx_drv_stats(struct ifla_xdp_stats *if_stats, + const struct xdp_rx_drv_stats *rstats) +{ + u32 start; + + do { + start = u64_stats_fetch_begin_irq(&rstats->syncp); + + if_stats->packets = u64_stats_read(&rstats->packets); + if_stats->bytes = u64_stats_read(&rstats->bytes); + if_stats->pass = u64_stats_read(&rstats->pass); + if_stats->drop = u64_stats_read(&rstats->drop); + if_stats->tx = u64_stats_read(&rstats->tx); + if_stats->tx_errors = u64_stats_read(&rstats->tx_errors); + if_stats->redirect = u64_stats_read(&rstats->redirect); + if_stats->redirect_errors = + u64_stats_read(&rstats->redirect_errors); + if_stats->aborted = u64_stats_read(&rstats->aborted); + if_stats->invalid = u64_stats_read(&rstats->invalid); + } while (u64_stats_fetch_retry_irq(&rstats->syncp, start)); +} +EXPORT_SYMBOL_GPL(xdp_fetch_rx_drv_stats); + +/** + * xdp_fetch_tx_drv_stats - helper for implementing .ndo_get_xdp_stats() + * @if_stats: target container passed from rtnetlink core + * @tstats: driver container if it uses generic xdp_tx_drv_stats + * + * Fetches Tx path XDP statistics from a suggested driver structure to + * the one used by rtnetlink, respecting atomic/seqcount synchronization. + */ +void xdp_fetch_tx_drv_stats(struct ifla_xdp_stats *if_stats, + const struct xdp_tx_drv_stats *tstats) +{ + u32 start; + + do { + start = u64_stats_fetch_begin_irq(&tstats->syncp); + + if_stats->xmit_packets = u64_stats_read(&tstats->packets); + if_stats->xmit_bytes = u64_stats_read(&tstats->bytes); + if_stats->xmit_errors = u64_stats_read(&tstats->errors); + if_stats->xmit_full = u64_stats_read(&tstats->full); + } while (u64_stats_fetch_retry_irq(&tstats->syncp, start)); +} +EXPORT_SYMBOL_GPL(xdp_fetch_tx_drv_stats); + +/** + * xdp_get_drv_stats_generic - generic implementation of .ndo_get_xdp_stats() + * @dev: network interface device structure + * @attr_id: type of statistics (XDP, XSK, ...) + * @attr_data: target stats container + * + * Returns 0 on success, -%EOPNOTSUPP if either driver or this function doesn't + * support this attr_id, -%ENODATA if the driver supports attr_id, but can't + * provide anything right now, and -%EINVAL if driver configuration is invalid. + */ +int xdp_get_drv_stats_generic(const struct net_device *dev, u32 attr_id, + void *attr_data) +{ + const bool xsk = attr_id == IFLA_XDP_XSTATS_TYPE_XSK; + const struct xdp_drv_stats *drv_iter = dev->xstats; + const struct net_device_ops *ops = dev->netdev_ops; + struct ifla_xdp_stats *iter = attr_data; + int nch; + u32 i; + + switch (attr_id) { + case IFLA_XDP_XSTATS_TYPE_XDP: + if (unlikely(!ops->ndo_bpf)) + return -EINVAL; + + break; + case IFLA_XDP_XSTATS_TYPE_XSK: + if (!ops->ndo_xsk_wakeup) + return -EOPNOTSUPP; + + break; + default: + return -EOPNOTSUPP; + } + + if (unlikely(!drv_iter || !ops->ndo_get_xdp_stats_nch)) + return -EINVAL; + + nch = ops->ndo_get_xdp_stats_nch(dev, attr_id); + switch (nch) { + case 0: + /* Stats are shared across the netdev */ + nch = 1; + break; + case 1 ... INT_MAX: + /* Stats are per-channel */ + break; + default: + return nch; + } + + for (i = 0; i < nch; i++) { + const struct xdp_rx_drv_stats *rstats; + const struct xdp_tx_drv_stats *tstats; + + rstats = xsk ? &drv_iter->xsk_rx : &drv_iter->xdp_rx; + xdp_fetch_rx_drv_stats(iter, rstats); + + tstats = xsk ? &drv_iter->xsk_tx : &drv_iter->xdp_tx; + xdp_fetch_tx_drv_stats(iter, tstats); + + drv_iter++; + iter++; + } + + return 0; +} +EXPORT_SYMBOL_GPL(xdp_get_drv_stats_generic);