From 93a1554e0ca3cbabfb90d8d6edeb1680597283a3 Mon Sep 17 00:00:00 2001 From: Alexander Duyck Date: Fri, 4 May 2012 14:26:56 +0000 Subject: [PATCH] skb: Add inline helper for getting the skb end offset from head [ Upstream commit ec47ea82477404631d49b8e568c71826c9b663ac ] With the recent changes for how we compute the skb truesize it occurs to me we are probably going to have a lot of calls to skb_end_pointer - skb->head. Instead of running all over the place doing that it would make more sense to just make it a separate inline skb_end_offset(skb) that way we can return the correct value without having gcc having to do all the optimization to cancel out skb->head - skb->head. Signed-off-by: Alexander Duyck Acked-by: Eric Dumazet Signed-off-by: David S. Miller Signed-off-by: Ben Hutchings --- drivers/atm/ambassador.c | 2 +- drivers/atm/idt77252.c | 2 +- drivers/net/wimax/i2400m/usb-rx.c | 2 +- drivers/staging/octeon/ethernet-tx.c | 2 +- include/linux/skbuff.h | 12 +++++++++++- net/core/skbuff.c | 9 ++++----- 6 files changed, 19 insertions(+), 10 deletions(-) diff --git a/drivers/atm/ambassador.c b/drivers/atm/ambassador.c index f8f41e0e8a8c..89b30f32ba68 100644 --- a/drivers/atm/ambassador.c +++ b/drivers/atm/ambassador.c @@ -802,7 +802,7 @@ static void fill_rx_pool (amb_dev * dev, unsigned char pool, } // cast needed as there is no %? for pointer differences PRINTD (DBG_SKB, "allocated skb at %p, head %p, area %li", - skb, skb->head, (long) (skb_end_pointer(skb) - skb->head)); + skb, skb->head, (long) skb_end_offset(skb)); rx.handle = virt_to_bus (skb); rx.host_address = cpu_to_be32 (virt_to_bus (skb->data)); if (rx_give (dev, &rx, pool)) diff --git a/drivers/atm/idt77252.c b/drivers/atm/idt77252.c index b0e75ce3c8fc..81845fa2a9cd 100644 --- a/drivers/atm/idt77252.c +++ b/drivers/atm/idt77252.c @@ -1258,7 +1258,7 @@ idt77252_rx_raw(struct idt77252_dev *card) tail = readl(SAR_REG_RAWCT); pci_dma_sync_single_for_cpu(card->pcidev, IDT77252_PRV_PADDR(queue), - skb_end_pointer(queue) - queue->head - 16, + skb_end_offset(queue) - 16, PCI_DMA_FROMDEVICE); while (head != tail) { diff --git a/drivers/net/wimax/i2400m/usb-rx.c b/drivers/net/wimax/i2400m/usb-rx.c index e3257681e360..b78ee676e102 100644 --- a/drivers/net/wimax/i2400m/usb-rx.c +++ b/drivers/net/wimax/i2400m/usb-rx.c @@ -277,7 +277,7 @@ retry: d_printf(1, dev, "RX: size changed to %d, received %d, " "copied %d, capacity %ld\n", rx_size, read_size, rx_skb->len, - (long) (skb_end_pointer(new_skb) - new_skb->head)); + (long) skb_end_offset(new_skb)); goto retry; } /* In most cases, it happens due to the hardware scheduling a diff --git a/drivers/staging/octeon/ethernet-tx.c b/drivers/staging/octeon/ethernet-tx.c index 2542c3743904..c5da0d24b4aa 100644 --- a/drivers/staging/octeon/ethernet-tx.c +++ b/drivers/staging/octeon/ethernet-tx.c @@ -344,7 +344,7 @@ int cvm_oct_xmit(struct sk_buff *skb, struct net_device *dev) } if (unlikely (skb->truesize != - sizeof(*skb) + skb_end_pointer(skb) - skb->head)) { + sizeof(*skb) + skb_end_offset(skb))) { /* printk("TX buffer truesize has been changed\n"); */ diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index 13bd6d0e43c5..c445e5221d49 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -617,11 +617,21 @@ static inline unsigned char *skb_end_pointer(const struct sk_buff *skb) { return skb->head + skb->end; } + +static inline unsigned int skb_end_offset(const struct sk_buff *skb) +{ + return skb->end; +} #else static inline unsigned char *skb_end_pointer(const struct sk_buff *skb) { return skb->end; } + +static inline unsigned int skb_end_offset(const struct sk_buff *skb) +{ + return skb->end - skb->head; +} #endif /* Internal */ @@ -2549,7 +2559,7 @@ static inline bool skb_is_recycleable(const struct sk_buff *skb, int skb_size) return false; skb_size = SKB_DATA_ALIGN(skb_size + NET_SKB_PAD); - if (skb_end_pointer(skb) - skb->head < skb_size) + if (skb_end_offset(skb) < skb_size) return false; if (skb_shared(skb) || skb_cloned(skb)) diff --git a/net/core/skbuff.c b/net/core/skbuff.c index 8ae2e436c249..9204d9b747f2 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -743,7 +743,7 @@ static void copy_skb_header(struct sk_buff *new, const struct sk_buff *old) struct sk_buff *skb_copy(const struct sk_buff *skb, gfp_t gfp_mask) { int headerlen = skb_headroom(skb); - unsigned int size = (skb_end_pointer(skb) - skb->head) + skb->data_len; + unsigned int size = skb_end_offset(skb) + skb->data_len; struct sk_buff *n = alloc_skb(size, gfp_mask); if (!n) @@ -843,7 +843,7 @@ int pskb_expand_head(struct sk_buff *skb, int nhead, int ntail, { int i; u8 *data; - int size = nhead + (skb_end_pointer(skb) - skb->head) + ntail; + int size = nhead + skb_end_offset(skb) + ntail; long off; bool fastpath; @@ -2642,14 +2642,13 @@ struct sk_buff *skb_segment(struct sk_buff *skb, u32 features) if (unlikely(!nskb)) goto err; - hsize = skb_end_pointer(nskb) - nskb->head; + hsize = skb_end_offset(nskb); if (skb_cow_head(nskb, doffset + headroom)) { kfree_skb(nskb); goto err; } - nskb->truesize += skb_end_pointer(nskb) - nskb->head - - hsize; + nskb->truesize += skb_end_offset(nskb) - hsize; skb_release_head_state(nskb); __skb_push(nskb, doffset); } else { -- 2.39.2