From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-12.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E0F4CC433F5 for ; Fri, 3 Sep 2021 16:08:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B7F42610E7 for ; Fri, 3 Sep 2021 16:08:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1349877AbhICQJ0 (ORCPT ); Fri, 3 Sep 2021 12:09:26 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33274 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235671AbhICQJZ (ORCPT ); Fri, 3 Sep 2021 12:09:25 -0400 Received: from mail-oi1-x22a.google.com (mail-oi1-x22a.google.com [IPv6:2607:f8b0:4864:20::22a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 64B3AC061575; Fri, 3 Sep 2021 09:08:25 -0700 (PDT) Received: by mail-oi1-x22a.google.com with SMTP id 6so7438884oiy.8; Fri, 03 Sep 2021 09:08:25 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=95vc7j645Giw7pgm0LPbTQoMXq0lNn25nYeMz4b7vQQ=; b=d3aRozP+MdGqu3bBJI16gBesVBilPsDSHsmJ35oYg8XB7CLgd4BxKoiCkX1xFb5qwQ 6sBylX2dMSzIB0XflbZspPUnBkYW5Z4ZPL2lWqMLujvqvmQieXzzFFv4vvCDvRCeOgOw XhTGMSlawVgd75VdhcCr0GBbCs3YdVrNzqdMWhvIJSUDTfQV5O4J+F/+1ejBUN1dnqX+ kMm+qY+UMHHuFQdvqwpe59ph3nyLFEv8gng1GLXaxdQLCWsCsVnIUaExYscGVA/dfu38 tAzqIdskuTCsOyivbqeGi00Es+YvEIBVwwl7I0zrUFxdiurDVa1k4kTcq67a1wO8B2/d qrxQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=95vc7j645Giw7pgm0LPbTQoMXq0lNn25nYeMz4b7vQQ=; b=rDRzL2E/IOMYHMMzq9WlsSxx/FiYYm+hbTSL/y+bBsuI8hf/J60dVqDpHic1qH5uOZ Qh4lEOr+9/yFpI0Z4URc6BRlyhB7fw6GjpH4fUn0BSIdUlxfM+LgsWCuISzAS/4Ja+vK Kfcww6XtOw8udUKVOvHLGTUL0x2JFIBPeMzZOU8AgXDfG64WFRvdtzNGCUxMyp8wHGhw nYEAWuMgvq/fpJ3b6r5LXQnbremsyfV8RRLoMYhwKTklDCxxmzOupq56zTkkdcEY5h2F dvxv78lksHKYjNLzL0JMJWn7x7UZ4dTFufKEfhSIc8fYZeN/7NQavQMXbNBPDTDtOe3K 7wTw== X-Gm-Message-State: AOAM532GXfWvmRprFJVzSjl85xKt8Xu2nC1iMcFKg3N9EfwiAvFTxq88 O7zrvq+dQAAPWsRHJx+vILFIGnZ8NEOz1Uz7ptY= X-Google-Smtp-Source: ABdhPJzsHV9woT1enKCdPb+YWhHRoSxixF1VZVhDQ4YtcYGokfdS0gAZFXaZzxa4UbxE0k9QgsrDP3UR98c27jnmINY= X-Received: by 2002:a05:6808:208b:: with SMTP id s11mr6859608oiw.95.1630685304608; Fri, 03 Sep 2021 09:08:24 -0700 (PDT) MIME-Version: 1.0 References: <20210901101206.50274-1-kerneljasonxing@gmail.com> In-Reply-To: <20210901101206.50274-1-kerneljasonxing@gmail.com> From: Jason Xing Date: Sat, 4 Sep 2021 00:07:48 +0800 Message-ID: Subject: Re: [PATCH v7] ixgbe: let the xdpdrv work with more than 64 cpus To: Jesse Brandeburg , "Nguyen, Anthony L" , David Miller , kuba@kernel.org, ast@kernel.org, daniel@iogearbox.net, hawk@kernel.org, john.fastabend@gmail.com, andrii@kernel.org, kafai@fb.com, songliubraving@fb.com, yhs@fb.com, kpsingh@kernel.org Cc: intel-wired-lan@lists.osuosl.org, netdev , LKML , bpf@vger.kernel.org, Jason Xing , kernel test robot , Shujin Li Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org On Wed, Sep 1, 2021 at 6:12 PM wrote: > > From: Jason Xing > > Originally, ixgbe driver doesn't allow the mounting of xdpdrv if the > server is equipped with more than 64 cpus online. So it turns out that > the loading of xdpdrv causes the "NOMEM" failure. > > Actually, we can adjust the algorithm and then make it work through > mapping the current cpu to some xdp ring with the protect of @tx_lock. > > Here're some numbers before/after applying this patch with xdp-example > loaded on the eth0X: > > As client (tx path): > Before After > TCP_STREAM send-64 734.14 714.20 > TCP_STREAM send-128 1401.91 1395.05 > TCP_STREAM send-512 5311.67 5292.84 > TCP_STREAM send-1k 9277.40 9356.22 (not stable) > TCP_RR send-1 22559.75 21844.22 > TCP_RR send-128 23169.54 22725.13 > TCP_RR send-512 21670.91 21412.56 > > As server (rx path): > Before After > TCP_STREAM send-64 1416.49 1383.12 > TCP_STREAM send-128 3141.49 3055.50 > TCP_STREAM send-512 9488.73 9487.44 > TCP_STREAM send-1k 9491.17 9356.22 (not stable) > TCP_RR send-1 23617.74 23601.60 > ... > > Notice: the TCP_RR mode is unstable as the official document explaines. > > I tested many times with different parameters combined through netperf. > Though the result is not that accurate, I cannot see much influence on > this patch. The static key is places on the hot path, but it actually > shouldn't cause a huge regression theoretically. > > Fixes: 33fdc82f08 ("ixgbe: add support for XDP_TX action") > Reported-by: kernel test robot > Co-developed-by: Shujin Li > Signed-off-by: Shujin Li > Signed-off-by: Jason Xing > --- > v7: > - Factorized to a single spin_lock/unlock in ixgbe_xdp_xmit() (Eric) > - Handle other parts of lock/unlock in ixgbe_run_xdp()/_zc() (Jason) > Does this change make any sense? I think it is much clearer than the v6 patch and they both have the same idea. Now I'm looking for more advice :-) Thanks, Jason > v6: > - Move the declaration of static-key to the proper position (Test Robot) > - Add reported-by tag (Jason) > - Add more detailed performance test results (Jason) > > v5: > - Change back to nr_cpu_ids (Eric) > > v4: > - Update the wrong commit messages. (Jason) > > v3: > - Change nr_cpu_ids to num_online_cpus() (Maciej) > - Rename MAX_XDP_QUEUES to IXGBE_MAX_XDP_QS (Maciej) > - Rename ixgbe_determine_xdp_cpu() to ixgbe_determine_xdp_q_idx() (Maciej) > - Wrap ixgbe_xdp_ring_update_tail() with lock into one function (Maciej) > > v2: > - Adjust cpu id in ixgbe_xdp_xmit(). (Jesper) > - Add a fallback path. (Maciej) > - Adjust other parts related to xdp ring. > --- > drivers/net/ethernet/intel/ixgbe/ixgbe.h | 23 +++++++++- > drivers/net/ethernet/intel/ixgbe/ixgbe_lib.c | 9 +++- > drivers/net/ethernet/intel/ixgbe/ixgbe_main.c | 50 ++++++++++++++++------ > .../net/ethernet/intel/ixgbe/ixgbe_txrx_common.h | 3 +- > drivers/net/ethernet/intel/ixgbe/ixgbe_xsk.c | 16 ++++--- > 5 files changed, 77 insertions(+), 24 deletions(-) > > diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe.h b/drivers/net/ethernet/intel/ixgbe/ixgbe.h > index a604552..4a69823 100644 > --- a/drivers/net/ethernet/intel/ixgbe/ixgbe.h > +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe.h > @@ -351,6 +351,7 @@ struct ixgbe_ring { > }; > u16 rx_offset; > struct xdp_rxq_info xdp_rxq; > + spinlock_t tx_lock; /* used in XDP mode */ > struct xsk_buff_pool *xsk_pool; > u16 ring_idx; /* {rx,tx,xdp}_ring back reference idx */ > u16 rx_buf_len; > @@ -375,11 +376,13 @@ enum ixgbe_ring_f_enum { > #define IXGBE_MAX_FCOE_INDICES 8 > #define MAX_RX_QUEUES (IXGBE_MAX_FDIR_INDICES + 1) > #define MAX_TX_QUEUES (IXGBE_MAX_FDIR_INDICES + 1) > -#define MAX_XDP_QUEUES (IXGBE_MAX_FDIR_INDICES + 1) > +#define IXGBE_MAX_XDP_QS (IXGBE_MAX_FDIR_INDICES + 1) > #define IXGBE_MAX_L2A_QUEUES 4 > #define IXGBE_BAD_L2A_QUEUE 3 > #define IXGBE_MAX_MACVLANS 63 > > +DECLARE_STATIC_KEY_FALSE(ixgbe_xdp_locking_key); > + > struct ixgbe_ring_feature { > u16 limit; /* upper limit on feature indices */ > u16 indices; /* current value of indices */ > @@ -629,7 +632,7 @@ struct ixgbe_adapter { > > /* XDP */ > int num_xdp_queues; > - struct ixgbe_ring *xdp_ring[MAX_XDP_QUEUES]; > + struct ixgbe_ring *xdp_ring[IXGBE_MAX_XDP_QS]; > unsigned long *af_xdp_zc_qps; /* tracks AF_XDP ZC enabled rings */ > > /* TX */ > @@ -772,6 +775,22 @@ struct ixgbe_adapter { > #endif /* CONFIG_IXGBE_IPSEC */ > }; > > +static inline int ixgbe_determine_xdp_q_idx(int cpu) > +{ > + if (static_key_enabled(&ixgbe_xdp_locking_key)) > + return cpu % IXGBE_MAX_XDP_QS; > + else > + return cpu; > +} > + > +static inline > +struct ixgbe_ring *ixgbe_determine_xdp_ring(struct ixgbe_adapter *adapter) > +{ > + int index = ixgbe_determine_xdp_q_idx(smp_processor_id()); > + > + return adapter->xdp_ring[index]; > +} > + > static inline u8 ixgbe_max_rss_indices(struct ixgbe_adapter *adapter) > { > switch (adapter->hw.mac.type) { > diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_lib.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_lib.c > index 0218f6c..86b1116 100644 > --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_lib.c > +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_lib.c > @@ -299,7 +299,10 @@ static void ixgbe_cache_ring_register(struct ixgbe_adapter *adapter) > > static int ixgbe_xdp_queues(struct ixgbe_adapter *adapter) > { > - return adapter->xdp_prog ? nr_cpu_ids : 0; > + int queues; > + > + queues = min_t(int, IXGBE_MAX_XDP_QS, nr_cpu_ids); > + return adapter->xdp_prog ? queues : 0; > } > > #define IXGBE_RSS_64Q_MASK 0x3F > @@ -947,6 +950,7 @@ static int ixgbe_alloc_q_vector(struct ixgbe_adapter *adapter, > ring->count = adapter->tx_ring_count; > ring->queue_index = xdp_idx; > set_ring_xdp(ring); > + spin_lock_init(&ring->tx_lock); > > /* assign ring to adapter */ > WRITE_ONCE(adapter->xdp_ring[xdp_idx], ring); > @@ -1032,6 +1036,9 @@ static void ixgbe_free_q_vector(struct ixgbe_adapter *adapter, int v_idx) > adapter->q_vector[v_idx] = NULL; > __netif_napi_del(&q_vector->napi); > > + if (static_key_enabled(&ixgbe_xdp_locking_key)) > + static_branch_dec(&ixgbe_xdp_locking_key); > + > /* > * after a call to __netif_napi_del() napi may still be used and > * ixgbe_get_stats64() might access the rings on this vector, > diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c > index 14aea40..8b9e21b 100644 > --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c > +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c > @@ -165,6 +165,9 @@ static int ixgbe_notify_dca(struct notifier_block *, unsigned long event, > MODULE_DESCRIPTION("Intel(R) 10 Gigabit PCI Express Network Driver"); > MODULE_LICENSE("GPL v2"); > > +DEFINE_STATIC_KEY_FALSE(ixgbe_xdp_locking_key); > +EXPORT_SYMBOL(ixgbe_xdp_locking_key); > + > static struct workqueue_struct *ixgbe_wq; > > static bool ixgbe_check_cfg_remove(struct ixgbe_hw *hw, struct pci_dev *pdev); > @@ -2197,6 +2200,7 @@ static struct sk_buff *ixgbe_run_xdp(struct ixgbe_adapter *adapter, > { > int err, result = IXGBE_XDP_PASS; > struct bpf_prog *xdp_prog; > + struct ixgbe_ring *ring; > struct xdp_frame *xdpf; > u32 act; > > @@ -2215,7 +2219,12 @@ static struct sk_buff *ixgbe_run_xdp(struct ixgbe_adapter *adapter, > xdpf = xdp_convert_buff_to_frame(xdp); > if (unlikely(!xdpf)) > goto out_failure; > - result = ixgbe_xmit_xdp_ring(adapter, xdpf); > + ring = ixgbe_determine_xdp_ring(adapter); > + if (static_branch_unlikely(&ixgbe_xdp_locking_key)) > + spin_lock(&ring->tx_lock); > + result = ixgbe_xmit_xdp_ring(ring, xdpf); > + if (static_branch_unlikely(&ixgbe_xdp_locking_key)) > + spin_unlock(&ring->tx_lock); > if (result == IXGBE_XDP_CONSUMED) > goto out_failure; > break; > @@ -2422,13 +2431,9 @@ static int ixgbe_clean_rx_irq(struct ixgbe_q_vector *q_vector, > xdp_do_flush_map(); > > if (xdp_xmit & IXGBE_XDP_TX) { > - struct ixgbe_ring *ring = adapter->xdp_ring[smp_processor_id()]; > + struct ixgbe_ring *ring = ixgbe_determine_xdp_ring(adapter); > > - /* Force memory writes to complete before letting h/w > - * know there are new descriptors to fetch. > - */ > - wmb(); > - writel(ring->next_to_use, ring->tail); > + ixgbe_xdp_ring_update_tail_locked(ring); > } > > u64_stats_update_begin(&rx_ring->syncp); > @@ -6320,7 +6325,7 @@ static int ixgbe_sw_init(struct ixgbe_adapter *adapter, > if (ixgbe_init_rss_key(adapter)) > return -ENOMEM; > > - adapter->af_xdp_zc_qps = bitmap_zalloc(MAX_XDP_QUEUES, GFP_KERNEL); > + adapter->af_xdp_zc_qps = bitmap_zalloc(IXGBE_MAX_XDP_QS, GFP_KERNEL); > if (!adapter->af_xdp_zc_qps) > return -ENOMEM; > > @@ -8536,10 +8541,9 @@ static u16 ixgbe_select_queue(struct net_device *dev, struct sk_buff *skb, > } > > #endif > -int ixgbe_xmit_xdp_ring(struct ixgbe_adapter *adapter, > +int ixgbe_xmit_xdp_ring(struct ixgbe_ring *ring, > struct xdp_frame *xdpf) > { > - struct ixgbe_ring *ring = adapter->xdp_ring[smp_processor_id()]; > struct ixgbe_tx_buffer *tx_buffer; > union ixgbe_adv_tx_desc *tx_desc; > u32 len, cmd_type; > @@ -10130,8 +10134,13 @@ static int ixgbe_xdp_setup(struct net_device *dev, struct bpf_prog *prog) > return -EINVAL; > } > > - if (nr_cpu_ids > MAX_XDP_QUEUES) > + /* if the number of cpus is much larger than the maximum of queues, > + * we should stop it and then return with NOMEM like before. > + */ > + if (nr_cpu_ids > IXGBE_MAX_XDP_QS * 2) > return -ENOMEM; > + else if (nr_cpu_ids > IXGBE_MAX_XDP_QS) > + static_branch_inc(&ixgbe_xdp_locking_key); > > old_prog = xchg(&adapter->xdp_prog, prog); > need_reset = (!!prog != !!old_prog); > @@ -10195,6 +10204,15 @@ void ixgbe_xdp_ring_update_tail(struct ixgbe_ring *ring) > writel(ring->next_to_use, ring->tail); > } > > +void ixgbe_xdp_ring_update_tail_locked(struct ixgbe_ring *ring) > +{ > + if (static_branch_unlikely(&ixgbe_xdp_locking_key)) > + spin_lock(&ring->tx_lock); > + ixgbe_xdp_ring_update_tail(ring); > + if (static_branch_unlikely(&ixgbe_xdp_locking_key)) > + spin_unlock(&ring->tx_lock); > +} > + > static int ixgbe_xdp_xmit(struct net_device *dev, int n, > struct xdp_frame **frames, u32 flags) > { > @@ -10212,18 +10230,21 @@ static int ixgbe_xdp_xmit(struct net_device *dev, int n, > /* During program transitions its possible adapter->xdp_prog is assigned > * but ring has not been configured yet. In this case simply abort xmit. > */ > - ring = adapter->xdp_prog ? adapter->xdp_ring[smp_processor_id()] : NULL; > + ring = adapter->xdp_prog ? ixgbe_determine_xdp_ring(adapter) : NULL; > if (unlikely(!ring)) > return -ENXIO; > > if (unlikely(test_bit(__IXGBE_TX_DISABLED, &ring->state))) > return -ENXIO; > > + if (static_branch_unlikely(&ixgbe_xdp_locking_key)) > + spin_lock(&ring->tx_lock); > + > for (i = 0; i < n; i++) { > struct xdp_frame *xdpf = frames[i]; > int err; > > - err = ixgbe_xmit_xdp_ring(adapter, xdpf); > + err = ixgbe_xmit_xdp_ring(ring, xdpf); > if (err != IXGBE_XDP_TX) > break; > nxmit++; > @@ -10232,6 +10253,9 @@ static int ixgbe_xdp_xmit(struct net_device *dev, int n, > if (unlikely(flags & XDP_XMIT_FLUSH)) > ixgbe_xdp_ring_update_tail(ring); > > + if (static_branch_unlikely(&ixgbe_xdp_locking_key)) > + spin_unlock(&ring->tx_lock); > + > return nxmit; > } > > diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_txrx_common.h b/drivers/net/ethernet/intel/ixgbe/ixgbe_txrx_common.h > index 2aeec78..a82533f 100644 > --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_txrx_common.h > +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_txrx_common.h > @@ -12,7 +12,7 @@ > #define IXGBE_TXD_CMD (IXGBE_TXD_CMD_EOP | \ > IXGBE_TXD_CMD_RS) > > -int ixgbe_xmit_xdp_ring(struct ixgbe_adapter *adapter, > +int ixgbe_xmit_xdp_ring(struct ixgbe_ring *ring, > struct xdp_frame *xdpf); > bool ixgbe_cleanup_headers(struct ixgbe_ring *rx_ring, > union ixgbe_adv_rx_desc *rx_desc, > @@ -23,6 +23,7 @@ void ixgbe_process_skb_fields(struct ixgbe_ring *rx_ring, > void ixgbe_rx_skb(struct ixgbe_q_vector *q_vector, > struct sk_buff *skb); > void ixgbe_xdp_ring_update_tail(struct ixgbe_ring *ring); > +void ixgbe_xdp_ring_update_tail_locked(struct ixgbe_ring *ring); > void ixgbe_irq_rearm_queues(struct ixgbe_adapter *adapter, u64 qmask); > > void ixgbe_txrx_ring_disable(struct ixgbe_adapter *adapter, int ring); > diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_xsk.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_xsk.c > index b1d22e4..db2bc58 100644 > --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_xsk.c > +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_xsk.c > @@ -100,6 +100,7 @@ static int ixgbe_run_xdp_zc(struct ixgbe_adapter *adapter, > { > int err, result = IXGBE_XDP_PASS; > struct bpf_prog *xdp_prog; > + struct ixgbe_ring *ring; > struct xdp_frame *xdpf; > u32 act; > > @@ -120,7 +121,12 @@ static int ixgbe_run_xdp_zc(struct ixgbe_adapter *adapter, > xdpf = xdp_convert_buff_to_frame(xdp); > if (unlikely(!xdpf)) > goto out_failure; > - result = ixgbe_xmit_xdp_ring(adapter, xdpf); > + ring = ixgbe_determine_xdp_ring(adapter); > + if (static_branch_unlikely(&ixgbe_xdp_locking_key)) > + spin_lock(&ring->tx_lock); > + result = ixgbe_xmit_xdp_ring(ring, xdpf); > + if (static_branch_unlikely(&ixgbe_xdp_locking_key)) > + spin_unlock(&ring->tx_lock); > if (result == IXGBE_XDP_CONSUMED) > goto out_failure; > break; > @@ -334,13 +340,9 @@ int ixgbe_clean_rx_irq_zc(struct ixgbe_q_vector *q_vector, > xdp_do_flush_map(); > > if (xdp_xmit & IXGBE_XDP_TX) { > - struct ixgbe_ring *ring = adapter->xdp_ring[smp_processor_id()]; > + struct ixgbe_ring *ring = ixgbe_determine_xdp_ring(adapter); > > - /* Force memory writes to complete before letting h/w > - * know there are new descriptors to fetch. > - */ > - wmb(); > - writel(ring->next_to_use, ring->tail); > + ixgbe_xdp_ring_update_tail_locked(ring); > } > > u64_stats_update_begin(&rx_ring->syncp); > -- > 1.8.3.1 >