From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christian Lamparter Subject: [PATCH v2 3/4] net: emac: remove IBM_EMAC_RX_SKB_HEADROOM Date: Mon, 22 Oct 2018 13:04:13 +0200 Message-ID: <6499b5b407dce973ec3f19fbfb62f7aa21ebf0f6.1540206214.git.chunkeey@gmail.com> References: <31e4c49844ba62c12e601f33ddea7d51182c359b.1540206214.git.chunkeey@gmail.com> <617f509eed6c844ffd2442b2c4b46b3fe6bc580a.1540206214.git.chunkeey@gmail.com> Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Cc: "David S . Miller" , Florian Fainelli To: netdev@vger.kernel.org Return-path: Received: from mail-ed1-f68.google.com ([209.85.208.68]:33183 "EHLO mail-ed1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728041AbeJVTWZ (ORCPT ); Mon, 22 Oct 2018 15:22:25 -0400 Received: by mail-ed1-f68.google.com with SMTP id r25-v6so2739582edy.0 for ; Mon, 22 Oct 2018 04:04:18 -0700 (PDT) In-Reply-To: <617f509eed6c844ffd2442b2c4b46b3fe6bc580a.1540206214.git.chunkeey@gmail.com> Sender: netdev-owner@vger.kernel.org List-ID: The EMAC driver had a custom IBM_EMAC_RX_SKB_HEADROOM Kconfig option that reserved additional skb headroom for RX. This patch removes the option and migrates the code to use napi_alloc_skb() and netdev_alloc_skb_ip_align() in its place. Signed-off-by: Christian Lamparter --- drivers/net/ethernet/ibm/emac/Kconfig | 12 ------ drivers/net/ethernet/ibm/emac/core.c | 57 +++++++++++++++++++-------- drivers/net/ethernet/ibm/emac/core.h | 10 ++--- 3 files changed, 43 insertions(+), 36 deletions(-) diff --git a/drivers/net/ethernet/ibm/emac/Kconfig b/drivers/net/ethernet/ibm/emac/Kconfig index 90d49191beb3..eacf7e141fdc 100644 --- a/drivers/net/ethernet/ibm/emac/Kconfig +++ b/drivers/net/ethernet/ibm/emac/Kconfig @@ -28,18 +28,6 @@ config IBM_EMAC_RX_COPY_THRESHOLD depends on IBM_EMAC default "256" -config IBM_EMAC_RX_SKB_HEADROOM - int "Additional RX skb headroom (bytes)" - depends on IBM_EMAC - default "0" - help - Additional receive skb headroom. Note, that driver - will always reserve at least 2 bytes to make IP header - aligned, so usually there is no need to add any additional - headroom. - - If unsure, set to 0. - config IBM_EMAC_DEBUG bool "Debugging" depends on IBM_EMAC diff --git a/drivers/net/ethernet/ibm/emac/core.c b/drivers/net/ethernet/ibm/emac/core.c index b5c4b7d3057d..388443e08674 100644 --- a/drivers/net/ethernet/ibm/emac/core.c +++ b/drivers/net/ethernet/ibm/emac/core.c @@ -1075,7 +1075,9 @@ static int emac_resize_rx_ring(struct emac_instance *dev, int new_mtu) /* Second pass, allocate new skbs */ for (i = 0; i < NUM_RX_BUFF; ++i) { - struct sk_buff *skb = alloc_skb(rx_skb_size, GFP_ATOMIC); + struct sk_buff *skb; + + skb = netdev_alloc_skb_ip_align(dev->ndev, rx_skb_size); if (!skb) { ret = -ENOMEM; goto oom; @@ -1084,7 +1086,6 @@ static int emac_resize_rx_ring(struct emac_instance *dev, int new_mtu) BUG_ON(!dev->rx_skb[i]); dev_kfree_skb(dev->rx_skb[i]); - skb_reserve(skb, EMAC_RX_SKB_HEADROOM + 2); dev->rx_desc[i].data_ptr = dma_map_single(&dev->ofdev->dev, skb->data - 2, rx_sync_size, DMA_FROM_DEVICE) + 2; @@ -1205,20 +1206,18 @@ static void emac_clean_rx_ring(struct emac_instance *dev) } } -static inline int emac_alloc_rx_skb(struct emac_instance *dev, int slot, - gfp_t flags) +static inline int +__emac_prepare_rx_skb(struct sk_buff *skb, struct emac_instance *dev, int slot) { - struct sk_buff *skb = alloc_skb(dev->rx_skb_size, flags); if (unlikely(!skb)) return -ENOMEM; dev->rx_skb[slot] = skb; dev->rx_desc[slot].data_len = 0; - skb_reserve(skb, EMAC_RX_SKB_HEADROOM + 2); dev->rx_desc[slot].data_ptr = - dma_map_single(&dev->ofdev->dev, skb->data - 2, dev->rx_sync_size, - DMA_FROM_DEVICE) + 2; + dma_map_single(&dev->ofdev->dev, skb->data - NET_IP_ALIGN, + dev->rx_sync_size, DMA_FROM_DEVICE) + NET_IP_ALIGN; wmb(); dev->rx_desc[slot].ctrl = MAL_RX_CTRL_EMPTY | (slot == (NUM_RX_BUFF - 1) ? MAL_RX_CTRL_WRAP : 0); @@ -1226,6 +1225,27 @@ static inline int emac_alloc_rx_skb(struct emac_instance *dev, int slot, return 0; } +static inline int +emac_alloc_rx_skb(struct emac_instance *dev, int slot) +{ + struct sk_buff *skb; + + skb = __netdev_alloc_skb_ip_align(dev->ndev, dev->rx_skb_size, + GFP_KERNEL); + + return __emac_prepare_rx_skb(skb, dev, slot); +} + +static inline int +emac_alloc_rx_skb_napi(struct emac_instance *dev, int slot) +{ + struct sk_buff *skb; + + skb = napi_alloc_skb(&dev->mal->napi, dev->rx_skb_size); + + return __emac_prepare_rx_skb(skb, dev, slot); +} + static void emac_print_link_status(struct emac_instance *dev) { if (netif_carrier_ok(dev->ndev)) @@ -1256,7 +1276,7 @@ static int emac_open(struct net_device *ndev) /* Allocate RX ring */ for (i = 0; i < NUM_RX_BUFF; ++i) - if (emac_alloc_rx_skb(dev, i, GFP_KERNEL)) { + if (emac_alloc_rx_skb(dev, i)) { printk(KERN_ERR "%s: failed to allocate RX ring\n", ndev->name); goto oom; @@ -1778,8 +1798,9 @@ static inline void emac_recycle_rx_skb(struct emac_instance *dev, int slot, DBG2(dev, "recycle %d %d" NL, slot, len); if (len) - dma_map_single(&dev->ofdev->dev, skb->data - 2, - EMAC_DMA_ALIGN(len + 2), DMA_FROM_DEVICE); + dma_map_single(&dev->ofdev->dev, skb->data - NET_IP_ALIGN, + SKB_DATA_ALIGN(len + NET_IP_ALIGN), + DMA_FROM_DEVICE); dev->rx_desc[slot].data_len = 0; wmb(); @@ -1887,16 +1908,18 @@ static int emac_poll_rx(void *param, int budget) } if (len && len < EMAC_RX_COPY_THRESH) { - struct sk_buff *copy_skb = - alloc_skb(len + EMAC_RX_SKB_HEADROOM + 2, GFP_ATOMIC); + struct sk_buff *copy_skb; + + copy_skb = napi_alloc_skb(&dev->mal->napi, len); if (unlikely(!copy_skb)) goto oom; - skb_reserve(copy_skb, EMAC_RX_SKB_HEADROOM + 2); - memcpy(copy_skb->data - 2, skb->data - 2, len + 2); + memcpy(copy_skb->data - NET_IP_ALIGN, + skb->data - NET_IP_ALIGN, + len + NET_IP_ALIGN); emac_recycle_rx_skb(dev, slot, len); skb = copy_skb; - } else if (unlikely(emac_alloc_rx_skb(dev, slot, GFP_ATOMIC))) + } else if (unlikely(emac_alloc_rx_skb_napi(dev, slot))) goto oom; skb_put(skb, len); @@ -1917,7 +1940,7 @@ static int emac_poll_rx(void *param, int budget) sg: if (ctrl & MAL_RX_CTRL_FIRST) { BUG_ON(dev->rx_sg_skb); - if (unlikely(emac_alloc_rx_skb(dev, slot, GFP_ATOMIC))) { + if (unlikely(emac_alloc_rx_skb_napi(dev, slot))) { DBG(dev, "rx OOM %d" NL, slot); ++dev->estats.rx_dropped_oom; emac_recycle_rx_skb(dev, slot, 0); diff --git a/drivers/net/ethernet/ibm/emac/core.h b/drivers/net/ethernet/ibm/emac/core.h index 0bcfe952a3cf..0faeb7c7e958 100644 --- a/drivers/net/ethernet/ibm/emac/core.h +++ b/drivers/net/ethernet/ibm/emac/core.h @@ -68,22 +68,18 @@ static inline int emac_rx_size(int mtu) return mal_rx_size(ETH_DATA_LEN + EMAC_MTU_OVERHEAD); } -#define EMAC_DMA_ALIGN(x) ALIGN((x), dma_get_cache_alignment()) - -#define EMAC_RX_SKB_HEADROOM \ - EMAC_DMA_ALIGN(CONFIG_IBM_EMAC_RX_SKB_HEADROOM) - /* Size of RX skb for the given MTU */ static inline int emac_rx_skb_size(int mtu) { int size = max(mtu + EMAC_MTU_OVERHEAD, emac_rx_size(mtu)); - return EMAC_DMA_ALIGN(size + 2) + EMAC_RX_SKB_HEADROOM; + + return SKB_DATA_ALIGN(size + NET_SKB_PAD + NET_IP_ALIGN); } /* RX DMA sync size */ static inline int emac_rx_sync_size(int mtu) { - return EMAC_DMA_ALIGN(emac_rx_size(mtu) + 2); + return SKB_DATA_ALIGN(emac_rx_size(mtu) + NET_IP_ALIGN); } /* Driver statistcs is split into two parts to make it more cache friendly: -- 2.19.1