ice: fix page reuse when PAGE_SIZE is over 8k

Architectures that have PAGE_SIZE >= 8192 such as arm64 should act the
same as x86 currently, meaning reuse of a page should only take place
when no one else is busy with it.

Do two things independently of underlying PAGE_SIZE:
- store the page count under ice_rx_buf::pgcnt
- then act upon its value vs ice_rx_buf::pagecnt_bias when making the
  decision regarding page reuse

Fixes: 2b245cb ("ice: Implement transmit and NAPI support")
Signed-off-by: Maciej Fijalkowski <[email protected]>
Tested-by: Chandan Kumar Rout <[email protected]> (A Contingent Worker at Intel)
Signed-off-by: Tony Nguyen <[email protected]>

Author: mfijalko

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

@@ -837,16 +837,15 @@ ice_can_reuse_rx_page(struct ice_rx_buf *rx_buf)
 	if (!dev_page_is_reusable(page))
 		return false;
 
-#if (PAGE_SIZE < 8192)
 	/* if we are only owner of page we can reuse it */
 	if (unlikely(rx_buf->pgcnt - pagecnt_bias > 1))
 		return false;
-#else
+#if (PAGE_SIZE >= 8192)
 #define ICE_LAST_OFFSET \
 	(SKB_WITH_OVERHEAD(PAGE_SIZE) - ICE_RXBUF_2048)
 	if (rx_buf->page_offset > ICE_LAST_OFFSET)
 		return false;
-#endif /* PAGE_SIZE < 8192) */
+#endif /* PAGE_SIZE >= 8192) */
 
 	/* If we have drained the page fragment pool we need to update
 	 * the pagecnt_bias and page count so that we fully restock the
@@ -949,12 +948,7 @@ ice_get_rx_buf(struct ice_rx_ring *rx_ring, const unsigned int size,
 	struct ice_rx_buf *rx_buf;
 
 	rx_buf = &rx_ring->rx_buf[ntc];
-	rx_buf->pgcnt =
-#if (PAGE_SIZE < 8192)
-		page_count(rx_buf->page);
-#else
-		0;
-#endif
+	rx_buf->pgcnt = page_count(rx_buf->page);
 	prefetchw(rx_buf->page);
 
 	if (!size)