[Intel-wired-lan] [PATCH S14 01/15] ice: Retrieve rx_buf in separate function
Anirudh Venkataramanan
anirudh.venkataramanan at intel.com
Wed Feb 13 18:51:01 UTC 2019
From: Maciej Fijalkowski <maciej.fijalkowski at intel.com>
Introduce ice_get_rx_buf, which will fetch the rx buffer and do the DMA
synchronization. Length of the packet that hardware rx descriptor
contains is now read in ice_clean_rx_irq, so we can feed ice_get_rx_buf
with it and resign from rx_desc passed as argument in ice_fetch_rx_buf
and ice_add_rx_frag.
Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski at intel.com>
Signed-off-by: Anirudh Venkataramanan <anirudh.venkataramanan at intel.com>
---
[Anirudh Venkataramanan <anirudh.venkataramanan at intel.com> cleaned up commit message]
---
drivers/net/ethernet/intel/ice/ice_txrx.c | 75 +++++++++++++++++--------------
1 file changed, 42 insertions(+), 33 deletions(-)
diff --git a/drivers/net/ethernet/intel/ice/ice_txrx.c b/drivers/net/ethernet/intel/ice/ice_txrx.c
index 64baedee6336..8c0a8b63670b 100644
--- a/drivers/net/ethernet/intel/ice/ice_txrx.c
+++ b/drivers/net/ethernet/intel/ice/ice_txrx.c
@@ -499,8 +499,8 @@ static bool ice_page_is_reserved(struct page *page)
/**
* ice_add_rx_frag - Add contents of Rx buffer to sk_buff
* @rx_buf: buffer containing page to add
- * @rx_desc: descriptor containing length of buffer written by hardware
* @skb: sk_buf to place the data into
+ * @size: the length of the packet
*
* This function will add the data contained in rx_buf->page to the skb.
* This is done either through a direct copy if the data in the buffer is
@@ -511,8 +511,8 @@ static bool ice_page_is_reserved(struct page *page)
* true if the buffer can be reused by the adapter.
*/
static bool
-ice_add_rx_frag(struct ice_rx_buf *rx_buf, union ice_32b_rx_flex_desc *rx_desc,
- struct sk_buff *skb)
+ice_add_rx_frag(struct ice_rx_buf *rx_buf, struct sk_buff *skb,
+ unsigned int size)
{
#if (PAGE_SIZE < 8192)
unsigned int truesize = ICE_RXBUF_2048;
@@ -522,10 +522,6 @@ ice_add_rx_frag(struct ice_rx_buf *rx_buf, union ice_32b_rx_flex_desc *rx_desc,
#endif /* PAGE_SIZE < 8192) */
struct page *page;
- unsigned int size;
-
- size = le16_to_cpu(rx_desc->wb.pkt_len) &
- ICE_RX_FLX_DESC_PKT_LEN_M;
page = rx_buf->page;
@@ -603,10 +599,35 @@ ice_reuse_rx_page(struct ice_ring *rx_ring, struct ice_rx_buf *old_buf)
*new_buf = *old_buf;
}
+/**
+ * ice_get_rx_buf - Fetch Rx buffer and synchronize data for use
+ * @rx_ring: Rx descriptor ring to transact packets on
+ * @size: size of buffer to add to skb
+ *
+ * This function will pull an Rx buffer from the ring and synchronize it
+ * for use by the CPU.
+ */
+static struct ice_rx_buf *
+ice_get_rx_buf(struct ice_ring *rx_ring, const unsigned int size)
+{
+ struct ice_rx_buf *rx_buf;
+
+ rx_buf = &rx_ring->rx_buf[rx_ring->next_to_clean];
+ prefetchw(rx_buf->page);
+
+ /* we are reusing so sync this buffer for CPU use */
+ dma_sync_single_range_for_cpu(rx_ring->dev, rx_buf->dma,
+ rx_buf->page_offset, size,
+ DMA_FROM_DEVICE);
+
+ return rx_buf;
+}
+
/**
* ice_fetch_rx_buf - Allocate skb and populate it
* @rx_ring: Rx descriptor ring to transact packets on
- * @rx_desc: descriptor containing info written by hardware
+ * @rx_buf: Rx buffer to pull data from
+ * @size: the length of the packet
*
* This function allocates an skb on the fly, and populates it with the page
* data from the current receive descriptor, taking care to set up the skb
@@ -614,20 +635,14 @@ ice_reuse_rx_page(struct ice_ring *rx_ring, struct ice_rx_buf *old_buf)
* necessary.
*/
static struct sk_buff *
-ice_fetch_rx_buf(struct ice_ring *rx_ring, union ice_32b_rx_flex_desc *rx_desc)
+ice_fetch_rx_buf(struct ice_ring *rx_ring, struct ice_rx_buf *rx_buf,
+ unsigned int size)
{
- struct ice_rx_buf *rx_buf;
- struct sk_buff *skb;
- struct page *page;
-
- rx_buf = &rx_ring->rx_buf[rx_ring->next_to_clean];
- page = rx_buf->page;
- prefetchw(page);
-
- skb = rx_buf->skb;
+ struct sk_buff *skb = rx_buf->skb;
if (likely(!skb)) {
- u8 *page_addr = page_address(page) + rx_buf->page_offset;
+ u8 *page_addr = page_address(rx_buf->page) +
+ rx_buf->page_offset;
/* prefetch first cache line of first page */
prefetch(page_addr);
@@ -644,25 +659,13 @@ ice_fetch_rx_buf(struct ice_ring *rx_ring, union ice_32b_rx_flex_desc *rx_desc)
return NULL;
}
- /* we will be copying header into skb->data in
- * pskb_may_pull so it is in our interest to prefetch
- * it now to avoid a possible cache miss
- */
- prefetchw(skb->data);
-
skb_record_rx_queue(skb, rx_ring->q_index);
} else {
- /* we are reusing so sync this buffer for CPU use */
- dma_sync_single_range_for_cpu(rx_ring->dev, rx_buf->dma,
- rx_buf->page_offset,
- ICE_RXBUF_2048,
- DMA_FROM_DEVICE);
-
rx_buf->skb = NULL;
}
/* pull page into skb */
- if (ice_add_rx_frag(rx_buf, rx_desc, skb)) {
+ if (ice_add_rx_frag(rx_buf, skb, size)) {
/* hand second half of page back to the ring */
ice_reuse_rx_page(rx_ring, rx_buf);
rx_ring->rx_stats.page_reuse_count++;
@@ -963,7 +966,9 @@ static int ice_clean_rx_irq(struct ice_ring *rx_ring, int budget)
/* start the loop to process RX packets bounded by 'budget' */
while (likely(total_rx_pkts < (unsigned int)budget)) {
union ice_32b_rx_flex_desc *rx_desc;
+ struct ice_rx_buf *rx_buf;
struct sk_buff *skb;
+ unsigned int size;
u16 stat_err_bits;
u16 vlan_tag = 0;
u8 rx_ptype;
@@ -993,8 +998,12 @@ static int ice_clean_rx_irq(struct ice_ring *rx_ring, int budget)
*/
dma_rmb();
+ size = le16_to_cpu(rx_desc->wb.pkt_len) &
+ ICE_RX_FLX_DESC_PKT_LEN_M;
+
+ rx_buf = ice_get_rx_buf(rx_ring, size);
/* allocate (if needed) and populate skb */
- skb = ice_fetch_rx_buf(rx_ring, rx_desc);
+ skb = ice_fetch_rx_buf(rx_ring, rx_buf, size);
if (!skb)
break;
--
2.14.5
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