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 <chunk...@gmail.com>
---
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
