On Thu, Jan 12, 2017 at 07:33:51PM +0300, Sergei Shtylyov wrote: > On 01/12/2017 04:18 PM, Simon Horman wrote: > > >... > > > >>>> Here, it stop once an untransmitted buffer is encountered... > >>> > >>>Yes, I see that now. > >>> > >>>I wonder if we should: > >>> > >>>a) paramatise ravb_tx_free() so it may either clear all transmitted buffers > >>> (current behaviour) or all buffers (new behaviour). > >>>b) provide a different version of this loop in ravb_ring_free() > >>> > >>>What are your thoughts? > >> > >> I'm voting for (b). > > > >Ok, something like this? > > > >@@ -215,6 +225,30 @@ static void ravb_ring_free(struct net_device *ndev, int q) > > } > > > > if (priv->tx_ring[q]) { > >+ for (; priv->cur_tx[q] - priv->dirty_tx[q] > 0; priv->dirty_tx[q]++) { > > You're still copying the loop logic from ravb_tx_free() while we (I > think) need a simple loop over all the descriptor ring. I thought the above may be better as it seems to me that only descriptors in the range described above could need to be freed. But simpler may be better. And I also noticed several other problems with the code I posted yesterday afternoon. How about something like this? @@ -215,6 +225,17 @@ static void ravb_ring_free(struct net_device *ndev, int q) } if (priv->tx_ring[q]) { + for (i = 0; i < priv->num_tx_ring[q] * NUM_TX_DESC; i++) { + struct ravb_tx_desc *desc = &priv->tx_ring[q][i]; + + if (desc->die_dt != DT_EEMPTY) { + u32 size = le16_to_cpu(desc->ds_tagl) & TX_DS; + + dma_unmap_single(ndev->dev.parent, + le32_to_cpu(desc->dptr), + size, DMA_TO_DEVICE); + } + } ring_size = sizeof(struct ravb_tx_desc) * (priv->num_tx_ring[q] * NUM_TX_DESC + 1); dma_free_coherent(ndev->dev.parent, ring_size, priv->tx_ring[q],