net: mediatek: fix threshold value

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>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
John Crispin 2016-06-10 13:28:04 +02:00 committed by David S. Miller
parent 2ff0bb6164
commit 04698cccb1

View File

@ -1033,8 +1033,7 @@ static int mtk_tx_alloc(struct mtk_eth *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