From 34ea0f209e0759158e363039852a04b1facc3acd Mon Sep 17 00:00:00 2001
From: John Crispin <john@phrozen.org>
Date: Tue, 3 May 2016 02:55:27 +0200
Subject: [PATCH 088/102] net-next: mediatek: fix threshold value
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The logic to calculate the threshold value for stopping the TX queue is
bad. Currently it will always use 1/2 of the rings size, which is way too
much. Set the threshold to MAX_SKB_FRAGS. This makes sure that the queue
is stopped when there is not enough room to accept an additional segment. 

Signed-off-by: John Crispin <john@phrozen.org>
---
 drivers/net/ethernet/mediatek/mtk_eth_soc.c |    3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

--- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c
+++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
@@ -1043,8 +1043,7 @@ static int mtk_tx_alloc(struct mtk_eth *
 	atomic_set(&ring->free_count, MTK_DMA_SIZE - 2);
 	ring->next_free = &ring->dma[0];
 	ring->last_free = &ring->dma[MTK_DMA_SIZE - 2];
-	ring->thresh = max((unsigned long)MTK_DMA_SIZE >> 2,
-			      MAX_SKB_FRAGS);
+	ring->thresh = MAX_SKB_FRAGS;
 
 	/* make sure that all changes to the dma ring are flushed before we
 	 * continue
