dmaengine: kill tx_list

The tx_list attribute of struct dma_async_tx_descriptor is common to
most, but not all dma driver implementations.  None of the upper level
code (dmaengine/async_tx) uses it, so allow drivers to implement it
locally if they need it.  This saves sizeof(struct list_head) bytes for
drivers that do not manage descriptors with a linked list (e.g.: ioatdma
v2,3).

Signed-off-by: Dan Williams <dan.j.williams@intel.com>

1 files changed, 0 insertions, 1 deletions

diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c
index 5a87384ea4ff..562d182eae66 100644
--- a/drivers/dma/dmaengine.c
+++ b/drivers/dma/dmaengine.c
@@ -933,7 +933,6 @@ void dma_async_tx_descriptor_init(struct dma_async_tx_descriptor *tx,
 {
         tx->chan = chan;
         spin_lock_init(&tx->lock);
-        INIT_LIST_HEAD(&tx->tx_list);
 }
 EXPORT_SYMBOL(dma_async_tx_descriptor_init);