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authorDavid S. Miller <davem@davemloft.net>2014-06-05 16:22:02 -0700
committerDavid S. Miller <davem@davemloft.net>2014-06-05 16:22:02 -0700
commitf666f87b9423fb534d2116206ace04495080f2b5 (patch)
tree23f929c890219d6ef412b4ff630adf501b70a3ec /drivers/net/xen-netback/netback.c
parentnet: phy: fix sparse warning in fixed.c (diff)
parentnet: filter: fix SKF_AD_PKTTYPE extension on big-endian (diff)
downloadlinux-dev-f666f87b9423fb534d2116206ace04495080f2b5.tar.xz
linux-dev-f666f87b9423fb534d2116206ace04495080f2b5.zip
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts: drivers/net/xen-netback/netback.c net/core/filter.c A filter bug fix overlapped some cleanups and a conversion over to some new insn generation macros. A xen-netback bug fix overlapped the addition of multi-queue support. Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net/xen-netback/netback.c')
-rw-r--r--drivers/net/xen-netback/netback.c36
1 files changed, 25 insertions, 11 deletions
diff --git a/drivers/net/xen-netback/netback.c b/drivers/net/xen-netback/netback.c
index 49efff9b99f4..1844a47636b6 100644
--- a/drivers/net/xen-netback/netback.c
+++ b/drivers/net/xen-netback/netback.c
@@ -168,7 +168,8 @@ bool xenvif_rx_ring_slots_available(struct xenvif_queue *queue, int needed)
* adding 'size' bytes to a buffer which currently contains 'offset'
* bytes.
*/
-static bool start_new_rx_buffer(int offset, unsigned long size, int head)
+static bool start_new_rx_buffer(int offset, unsigned long size, int head,
+ bool full_coalesce)
{
/* simple case: we have completely filled the current buffer. */
if (offset == MAX_BUFFER_OFFSET)
@@ -180,6 +181,7 @@ static bool start_new_rx_buffer(int offset, unsigned long size, int head)
* (i) this frag would fit completely in the next buffer
* and (ii) there is already some data in the current buffer
* and (iii) this is not the head buffer.
+ * and (iv) there is no need to fully utilize the buffers
*
* Where:
* - (i) stops us splitting a frag into two copies
@@ -190,6 +192,8 @@ static bool start_new_rx_buffer(int offset, unsigned long size, int head)
* by (ii) but is explicitly checked because
* netfront relies on the first buffer being
* non-empty and can crash otherwise.
+ * - (iv) is needed for skbs which can use up more than MAX_SKB_FRAGS
+ * slot
*
* This means we will effectively linearise small
* frags but do not needlessly split large buffers
@@ -197,7 +201,8 @@ static bool start_new_rx_buffer(int offset, unsigned long size, int head)
* own buffers as before.
*/
BUG_ON(size > MAX_BUFFER_OFFSET);
- if ((offset + size > MAX_BUFFER_OFFSET) && offset && !head)
+ if ((offset + size > MAX_BUFFER_OFFSET) && offset && !head &&
+ !full_coalesce)
return true;
return false;
@@ -232,6 +237,13 @@ static struct xenvif_rx_meta *get_next_rx_buffer(struct xenvif_queue *queue,
return meta;
}
+struct xenvif_rx_cb {
+ int meta_slots_used;
+ bool full_coalesce;
+};
+
+#define XENVIF_RX_CB(skb) ((struct xenvif_rx_cb *)(skb)->cb)
+
/*
* Set up the grant operations for this fragment. If it's a flipping
* interface, we also set up the unmap request from here.
@@ -266,7 +278,10 @@ static void xenvif_gop_frag_copy(struct xenvif_queue *queue, struct sk_buff *skb
if (bytes > size)
bytes = size;
- if (start_new_rx_buffer(npo->copy_off, bytes, *head)) {
+ if (start_new_rx_buffer(npo->copy_off,
+ bytes,
+ *head,
+ XENVIF_RX_CB(skb)->full_coalesce)) {
/*
* Netfront requires there to be some data in the head
* buffer.
@@ -548,12 +563,6 @@ static void xenvif_add_frag_responses(struct xenvif_queue *queue, int status,
}
}
-struct xenvif_rx_cb {
- int meta_slots_used;
-};
-
-#define XENVIF_RX_CB(skb) ((struct xenvif_rx_cb *)(skb)->cb)
-
void xenvif_kick_thread(struct xenvif_queue *queue)
{
wake_up(&queue->wq);
@@ -609,10 +618,15 @@ static void xenvif_rx_action(struct xenvif_queue *queue)
/* To avoid the estimate becoming too pessimal for some
* frontends that limit posted rx requests, cap the estimate
- * at MAX_SKB_FRAGS.
+ * at MAX_SKB_FRAGS. In this case netback will fully coalesce
+ * the skb into the provided slots.
*/
- if (max_slots_needed > MAX_SKB_FRAGS)
+ if (max_slots_needed > MAX_SKB_FRAGS) {
max_slots_needed = MAX_SKB_FRAGS;
+ XENVIF_RX_CB(skb)->full_coalesce = true;
+ } else {
+ XENVIF_RX_CB(skb)->full_coalesce = false;
+ }
/* We may need one more slot for GSO metadata */
if (skb_is_gso(skb) &&