From: Alexander Duyck <alexander.h.duyck@intel•com>
To: netdev@vger•kernel.org
Cc: davem@davemloft•net, eric.dumazet@gmail•com, jeffrey.t.kirsher@intel•com
Subject: [PATCH 3/3] skb: Add inline helper for getting the skb end offset from head
Date: Fri, 04 May 2012 17:26:56 -0700 [thread overview]
Message-ID: <20120505002656.21292.89799.stgit@gitlad.jf.intel.com> (raw)
In-Reply-To: <20120505001059.21292.31647.stgit@gitlad.jf.intel.com>
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 <alexander.h.duyck@intel•com>
---
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 | 12 ++++++------
6 files changed, 21 insertions(+), 11 deletions(-)
diff --git a/drivers/atm/ambassador.c b/drivers/atm/ambassador.c
index f8f41e0..89b30f3 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 1c05212..8974bd2 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 e325768..b78ee67 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 56d74dc..418ed03 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 37f5391..91ad5e2 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -645,11 +645,21 @@ 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 */
@@ -2558,7 +2568,7 @@ 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 17e4b1e..2c35da8 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -829,7 +829,7 @@ 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)
@@ -930,7 +930,7 @@ 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;
BUG_ON(nhead < 0);
@@ -2727,14 +2727,13 @@ struct sk_buff *skb_segment(struct sk_buff *skb, netdev_features_t 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 {
@@ -2883,7 +2882,8 @@ int skb_gro_receive(struct sk_buff **head, struct sk_buff *skb)
skb_frag_size_sub(frag, offset);
/* all fragments truesize : remove (head size + sk_buff) */
- delta_truesize = skb->truesize - SKB_TRUESIZE(skb_end_pointer(skb) - skb->head);
+ delta_truesize = skb->truesize -
+ SKB_TRUESIZE(skb_end_offset(skb));
skb->truesize -= skb->data_len;
skb->len -= skb->data_len;
next prev parent reply other threads:[~2012-05-05 0:26 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-05-05 0:26 [PATCH 0/3] First pass of cleanups for pskb_expand_head Alexander Duyck
2012-05-05 0:26 ` [PATCH 1/3] skb: Drop bad code from pskb_expand_head Alexander Duyck
2012-05-05 5:35 ` Eric Dumazet
2012-05-06 17:13 ` David Miller
2012-05-05 0:26 ` [PATCH 2/3] skb: Drop "fastpath" variable for skb_cloned check in pskb_expand_head Alexander Duyck
2012-05-05 5:37 ` Eric Dumazet
2012-05-06 17:13 ` David Miller
2012-05-05 0:26 ` Alexander Duyck [this message]
2012-05-05 5:39 ` [PATCH 3/3] skb: Add inline helper for getting the skb end offset from head Eric Dumazet
2012-05-06 17:13 ` David Miller
2012-05-05 5:44 ` [PATCH 0/3] First pass of cleanups for pskb_expand_head Eric Dumazet
2012-05-05 6:51 ` Alexander Duyck
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20120505002656.21292.89799.stgit@gitlad.jf.intel.com \
--to=alexander.h.duyck@intel$(echo .)com \
--cc=davem@davemloft$(echo .)net \
--cc=eric.dumazet@gmail$(echo .)com \
--cc=jeffrey.t.kirsher@intel$(echo .)com \
--cc=netdev@vger$(echo .)kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox