From 1bfa4d0cb5adf954e0f4870a3ecb7cb19506320c Mon Sep 17 00:00:00 2001
From: Bailey Forrest <bcf@google.com>
Date: Thu, 1 Jul 2021 20:13:36 -0700
Subject: [PATCH] gve: DQO: Remove incorrect prefetch
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>
---
drivers/net/ethernet/google/gve/gve_rx_dqo.c | 7 -------
1 file changed, 7 deletions(-)
diff --git a/drivers/net/ethernet/google/gve/gve_rx_dqo.c b/drivers/net/ethernet/google/gve/gve_rx_dqo.c
index 77bb8227f89b5..8500621b2cd41 100644
--- 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 *napi, struct gve_rx_ring *rx,
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);