Commit 1857ca42 authored by Maciej Fijalkowski's avatar Maciej Fijalkowski Committed by Jeff Kirsher
Browse files

ice: Get rid of ice_pull_tail 



Instead of adding a frag and later when dealing with EOP frame accessing
that frag in order to copy the headers onto linear part of skb, we can do
this in ice_add_rx_frag in case where the data_len is still 0 and frame
won't fit onto the linear part as a whole.

Function comment of ice_pull_tail was a bit misleading because of
mentioned optimizations that can be performed (drop a frag/maintaining
accurate truesize of skb) - it seems that this part of logic was dropped
and the comment was not updated to reflect this change.

Signed-off-by: default avatarMaciej Fijalkowski <maciej.fijalkowski@intel.com>
Signed-off-by: default avatarAnirudh Venkataramanan <anirudh.venkataramanan@intel.com>
Tested-by: default avatarAndrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: default avatarJeff Kirsher <jeffrey.t.kirsher@intel.com>
parent bbb97808

drivers/net/ethernet/intel/ice/ice_txrx.c

+24 −46
Original line number Diff line number Diff line
@@ -562,13 +562,17 @@ ice_add_rx_frag(struct ice_rx_buf *rx_buf, struct sk_buff *skb, 
	unsigned int truesize = ALIGN(size, L1_CACHE_BYTES);

#endif /* PAGE_SIZE < 8192) */

	struct page *page = rx_buf->page;

	unsigned int pull_len;

	unsigned char *va;



	va = page_address(page) + rx_buf->page_offset;

	if (unlikely(skb_is_nonlinear(skb)))

		goto add_tail_frag;



	/* will the data fit in the skb we allocated? if so, just

	 * copy it as it is pretty small anyway

	 */

	if (size <= ICE_RX_HDR_SIZE && !skb_is_nonlinear(skb)) {

		unsigned char *va = page_address(page) + rx_buf->page_offset;



	if (size <= ICE_RX_HDR_SIZE) {

		memcpy(__skb_put(skb, size), va, ALIGN(size, sizeof(long)));



		/* page is not reserved, we can reuse buffer as-is */
@@ -580,8 +584,24 @@ ice_add_rx_frag(struct ice_rx_buf *rx_buf, struct sk_buff *skb, 
		return false;

	}



	/* we need the header to contain the greater of either ETH_HLEN or

	 * 60 bytes if the skb->len is less than 60 for skb_pad.

	 */

	pull_len = eth_get_headlen(va, ICE_RX_HDR_SIZE);



	/* align pull length to size of long to optimize memcpy performance */

	memcpy(__skb_put(skb, pull_len), va, ALIGN(pull_len, sizeof(long)));



	/* the header from the frame that we're adding as a frag was added to

	 * linear part of skb so move the pointer past that header and

	 * reduce the size of data

	 */

	va += pull_len;

	size -= pull_len;



add_tail_frag:

	skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, page,

			rx_buf->page_offset, size, truesize);

			(unsigned long)va & ~PAGE_MASK, size, truesize);



	return ice_can_reuse_rx_page(rx_buf, truesize);

}
@@ -691,44 +711,6 @@ ice_fetch_rx_buf(struct ice_ring *rx_ring, struct ice_rx_buf *rx_buf, 
	return skb;

}



/**

 * ice_pull_tail - ice specific version of skb_pull_tail

 * @skb: pointer to current skb being adjusted

 *

 * This function is an ice specific version of __pskb_pull_tail. The

 * main difference between this version and the original function is that

 * this function can make several assumptions about the state of things

 * that allow for significant optimizations versus the standard function.

 * As a result we can do things like drop a frag and maintain an accurate

 * truesize for the skb.

 */

static void ice_pull_tail(struct sk_buff *skb)

{

	struct skb_frag_struct *frag = &skb_shinfo(skb)->frags[0];

	unsigned int pull_len;

	unsigned char *va;



	/* it is valid to use page_address instead of kmap since we are

	 * working with pages allocated out of the lomem pool per

	 * alloc_page(GFP_ATOMIC)

	 */

	va = skb_frag_address(frag);



	/* we need the header to contain the greater of either ETH_HLEN or

	 * 60 bytes if the skb->len is less than 60 for skb_pad.

	 */

	pull_len = eth_get_headlen(va, ICE_RX_HDR_SIZE);



	/* align pull length to size of long to optimize memcpy performance */

	skb_copy_to_linear_data(skb, va, ALIGN(pull_len, sizeof(long)));



	/* update all of the pointers */

	skb_frag_size_sub(frag, pull_len);

	frag->page_offset += pull_len;

	skb->data_len -= pull_len;

	skb->tail += pull_len;

}



/**

 * ice_cleanup_headers - Correct empty headers

 * @skb: pointer to current skb being fixed
@@ -743,10 +725,6 @@ static void ice_pull_tail(struct sk_buff *skb) 
 */

static bool ice_cleanup_headers(struct sk_buff *skb)

{

	/* place header in linear portion of buffer */

	if (skb_is_nonlinear(skb))

		ice_pull_tail(skb);



	/* if eth_skb_pad returns an error the skb was freed */

	if (eth_skb_pad(skb))

		return true;

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