openwrt/target/linux/generic/pending-5.4/770-09-net-ethernet-mtk_eth_soc-only-read-the-full-rx-descr.patch
John Audia 752cd29904 kernel: bump 5.4 to 5.4.124
Manually rebased:
  generic/hack-5.4/662-remove_pfifo_fast.patch

All other patches automatically rebased.

Build system: x86_64
Build-tested: ipq806x/R7800
Run-tested: ipq806x/R7800

No dmesg regressions, everything functional

Signed-off-by: John Audia <graysky@archlinux.us>
[manual changes to ramips/patches-5.10/835-asoc-add-mt7620-support.patch]
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
2021-06-06 00:25:25 +02:00

45 lines
1.3 KiB
Diff

From: Felix Fietkau <nbd@nbd.name>
Date: Thu, 27 Aug 2020 09:24:25 +0200
Subject: [PATCH] net: ethernet: mtk_eth_soc: only read the full rx
descriptor if DMA is done
Uncached memory access is expensive, and there is no need to access all
descriptor words if we can't process them anyway
Signed-off-by: Felix Fietkau <nbd@nbd.name>
---
--- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c
+++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
@@ -793,13 +793,18 @@ static inline int mtk_max_buf_size(int f
return buf_size;
}
-static inline void mtk_rx_get_desc(struct mtk_rx_dma *rxd,
+static inline bool mtk_rx_get_desc(struct mtk_rx_dma *rxd,
struct mtk_rx_dma *dma_rxd)
{
- rxd->rxd1 = READ_ONCE(dma_rxd->rxd1);
rxd->rxd2 = READ_ONCE(dma_rxd->rxd2);
+ if (!(rxd->rxd2 & RX_DMA_DONE))
+ return false;
+
+ rxd->rxd1 = READ_ONCE(dma_rxd->rxd1);
rxd->rxd3 = READ_ONCE(dma_rxd->rxd3);
rxd->rxd4 = READ_ONCE(dma_rxd->rxd4);
+
+ return true;
}
/* the qdma core needs scratch memory to be setup */
@@ -1271,8 +1276,7 @@ static int mtk_poll_rx(struct napi_struc
rxd = &ring->dma[idx];
data = ring->data[idx];
- mtk_rx_get_desc(&trxd, rxd);
- if (!(trxd.rxd2 & RX_DMA_DONE))
+ if (!mtk_rx_get_desc(&trxd, rxd))
break;
/* find out which mac the packet come from. values start at 1 */