From patchwork Thu Oct 29 19:28:44 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lorenzo Bianconi X-Patchwork-Id: 1390340 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Original-To: patchwork-incoming-netdev@ozlabs.org Delivered-To: patchwork-incoming-netdev@ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=none dis=none) header.from=kernel.org Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=default header.b=yw3LQAUt; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 4CMb9X2JFLz9sSG for ; Fri, 30 Oct 2020 06:29:36 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726254AbgJ2T3e (ORCPT ); Thu, 29 Oct 2020 15:29:34 -0400 Received: from mail.kernel.org ([198.145.29.99]:51456 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726228AbgJ2T3c (ORCPT ); Thu, 29 Oct 2020 15:29:32 -0400 Received: from lore-desk.redhat.com (unknown [151.66.29.159]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 822CE20796; Thu, 29 Oct 2020 19:28:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1603999740; bh=hDcWHAUde8Bu87cgNacUqUx/ZD7dajh8GlULMuqpcQ4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=yw3LQAUthmqZsTA7pLD/bIe2K3tvKJfif4IPZzQAhsL2OPgx7APXxiG6uxl3RulbB f0ptTNHXbPYkewUPMWbSxZPzRwZhDDr7BdwffoHKBD7Hmnpj29PWRp6VRaYK65Djn8 W/z4jSHrgdXGABqSk5cAlZIWp59XTW0DdHffQ4sE= From: Lorenzo Bianconi To: netdev@vger.kernel.org Cc: bpf@vger.kernel.org, lorenzo.bianconi@redhat.com, davem@davemloft.net, kuba@kernel.org, brouer@redhat.com, ilias.apalodimas@linaro.org Subject: [PATCH v2 net-next 1/4] net: xdp: introduce bulking for xdp tx return path Date: Thu, 29 Oct 2020 20:28:44 +0100 Message-Id: X-Mailer: git-send-email 2.26.2 In-Reply-To: References: MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org XDP bulk APIs introduce a defer/flush mechanism to return pages belonging to the same xdp_mem_allocator object (identified via the mem.id field) in bulk to optimize I-cache and D-cache since xdp_return_frame is usually run inside the driver NAPI tx completion loop. The bulk queue size is set to 16 to be aligned to how XDP_REDIRECT bulking works. The bulk is flushed when it is full or when mem.id changes. xdp_frame_bulk is usually stored/allocated on the function call-stack to avoid locking penalties. Current implementation considers only page_pool memory model. Convert mvneta driver to xdp_return_frame_bulk APIs. Suggested-by: Jesper Dangaard Brouer Signed-off-by: Lorenzo Bianconi --- drivers/net/ethernet/marvell/mvneta.c | 5 ++- include/net/xdp.h | 9 ++++ net/core/xdp.c | 61 +++++++++++++++++++++++++++ 3 files changed, 74 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/marvell/mvneta.c b/drivers/net/ethernet/marvell/mvneta.c index 54b0bf574c05..43ab8a73900e 100644 --- a/drivers/net/ethernet/marvell/mvneta.c +++ b/drivers/net/ethernet/marvell/mvneta.c @@ -1834,8 +1834,10 @@ static void mvneta_txq_bufs_free(struct mvneta_port *pp, struct netdev_queue *nq, bool napi) { unsigned int bytes_compl = 0, pkts_compl = 0; + struct xdp_frame_bulk bq; int i; + bq.xa = NULL; for (i = 0; i < num; i++) { struct mvneta_tx_buf *buf = &txq->buf[txq->txq_get_index]; struct mvneta_tx_desc *tx_desc = txq->descs + @@ -1857,9 +1859,10 @@ static void mvneta_txq_bufs_free(struct mvneta_port *pp, if (napi && buf->type == MVNETA_TYPE_XDP_TX) xdp_return_frame_rx_napi(buf->xdpf); else - xdp_return_frame(buf->xdpf); + xdp_return_frame_bulk(buf->xdpf, &bq); } } + xdp_flush_frame_bulk(&bq); netdev_tx_completed_queue(nq, pkts_compl, bytes_compl); } diff --git a/include/net/xdp.h b/include/net/xdp.h index 3814fb631d52..a1f48a73e6df 100644 --- a/include/net/xdp.h +++ b/include/net/xdp.h @@ -104,6 +104,12 @@ struct xdp_frame { struct net_device *dev_rx; /* used by cpumap */ }; +#define XDP_BULK_QUEUE_SIZE 16 +struct xdp_frame_bulk { + int count; + void *xa; + void *q[XDP_BULK_QUEUE_SIZE]; +}; static inline struct skb_shared_info * xdp_get_shared_info_from_frame(struct xdp_frame *frame) @@ -194,6 +200,9 @@ struct xdp_frame *xdp_convert_buff_to_frame(struct xdp_buff *xdp) void xdp_return_frame(struct xdp_frame *xdpf); void xdp_return_frame_rx_napi(struct xdp_frame *xdpf); void xdp_return_buff(struct xdp_buff *xdp); +void xdp_flush_frame_bulk(struct xdp_frame_bulk *bq); +void xdp_return_frame_bulk(struct xdp_frame *xdpf, + struct xdp_frame_bulk *bq); /* When sending xdp_frame into the network stack, then there is no * return point callback, which is needed to release e.g. DMA-mapping diff --git a/net/core/xdp.c b/net/core/xdp.c index 48aba933a5a8..66ac275a0360 100644 --- a/net/core/xdp.c +++ b/net/core/xdp.c @@ -380,6 +380,67 @@ void xdp_return_frame_rx_napi(struct xdp_frame *xdpf) } EXPORT_SYMBOL_GPL(xdp_return_frame_rx_napi); +/* XDP bulk APIs introduce a defer/flush mechanism to return + * pages belonging to the same xdp_mem_allocator object + * (identified via the mem.id field) in bulk to optimize + * I-cache and D-cache. + * The bulk queue size is set to 16 to be aligned to how + * XDP_REDIRECT bulking works. The bulk is flushed when + * it is full or when mem.id changes. + * xdp_frame_bulk is usually stored/allocated on the function + * call-stack to avoid locking penalties. + */ +void xdp_flush_frame_bulk(struct xdp_frame_bulk *bq) +{ + struct xdp_mem_allocator *xa = bq->xa; + int i; + + if (unlikely(!xa)) + return; + + for (i = 0; i < bq->count; i++) { + struct page *page = virt_to_head_page(bq->q[i]); + + page_pool_put_full_page(xa->page_pool, page, false); + } + bq->count = 0; +} +EXPORT_SYMBOL_GPL(xdp_flush_frame_bulk); + +void xdp_return_frame_bulk(struct xdp_frame *xdpf, + struct xdp_frame_bulk *bq) +{ + struct xdp_mem_info *mem = &xdpf->mem; + struct xdp_mem_allocator *xa; + + if (mem->type != MEM_TYPE_PAGE_POOL) { + __xdp_return(xdpf->data, &xdpf->mem, false); + return; + } + + rcu_read_lock(); + + xa = bq->xa; + if (unlikely(!xa)) { + xa = rhashtable_lookup(mem_id_ht, &mem->id, mem_id_rht_params); + bq->count = 0; + bq->xa = xa; + } + + if (bq->count == XDP_BULK_QUEUE_SIZE) + xdp_flush_frame_bulk(bq); + + if (mem->id != xa->mem.id) { + xdp_flush_frame_bulk(bq); + bq->xa = rhashtable_lookup(mem_id_ht, &mem->id, mem_id_rht_params); + } + + bq->q[bq->count++] = xdpf->data; + + rcu_read_unlock(); +} +EXPORT_SYMBOL_GPL(xdp_return_frame_bulk); + void xdp_return_buff(struct xdp_buff *xdp) { __xdp_return(xdp->data, &xdp->rxq->mem, true);