From: Bailey Forrest <bcf@google.com>
Date: Thu, 1 Jul 2021 20:13:36 -0700
Subject: gve: DQO: Remove incorrect prefetch
Patch-mainline: v5.14-rc2
Git-commit: 1bfa4d0cb5adf954e0f4870a3ecb7cb19506320c
References: bsc#1176940

The prefetch is incorrectly using the dma address instead of the virtual
address.

It's supposed to be:
prefetch((char *)buf_state->page_info.page_address +
	 buf_state->page_info.page_offset)

However, after correcting this mistake, there is no evidence of
performance improvement.

Fixes: 9b8dd5e5ea48 ("gve: DQO: Add RX path")
Signed-off-by: Bailey Forrest <bcf@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/net/ethernet/google/gve/gve_rx_dqo.c |    7 -------
 1 file changed, 7 deletions(-)

--- a/drivers/net/ethernet/google/gve/gve_rx_dqo.c
+++ b/drivers/net/ethernet/google/gve/gve_rx_dqo.c
@@ -566,13 +566,6 @@ static int gve_rx_dqo(struct napi_struct
 		return 0;
 	}
 
-	/* Prefetch the payload header. */
-	prefetch((char *)buf_state->addr + buf_state->page_info.page_offset);
-#if L1_CACHE_BYTES < 128
-	prefetch((char *)buf_state->addr + buf_state->page_info.page_offset +
-		 L1_CACHE_BYTES);
-#endif
-
 	if (eop && buf_len <= priv->rx_copybreak) {
 		rx->skb_head = gve_rx_copy(priv->dev, napi,
 					   &buf_state->page_info, buf_len, 0);