On 25-11-21, 11:00, Tudor Ambarus wrote:
> So that we don't use the same desc over and over again.
Please use full para in the changelog and not a continuation of the
patch title!
and why is wrong with using same desc over and over? Any benefits of not
doing so?
>
> Signed-off-by: Tudor Ambarus <tudor.ambarus@xxxxxxxxxxxxx>
> ---
> drivers/dma/at_xdmac.c | 23 ++++++++++++++---------
> 1 file changed, 14 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/dma/at_xdmac.c b/drivers/dma/at_xdmac.c
> index 2cc9af222681..8804a86a9bcc 100644
> --- a/drivers/dma/at_xdmac.c
> +++ b/drivers/dma/at_xdmac.c
> @@ -729,7 +729,8 @@ at_xdmac_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
> if (!desc) {
> dev_err(chan2dev(chan), "can't get descriptor\n");
> if (first)
> - list_splice_init(&first->descs_list, &atchan->free_descs_list);
> + list_splice_tail_init(&first->descs_list,
> + &atchan->free_descs_list);
> goto spin_unlock;
> }
>
> @@ -817,7 +818,8 @@ at_xdmac_prep_dma_cyclic(struct dma_chan *chan, dma_addr_t buf_addr,
> if (!desc) {
> dev_err(chan2dev(chan), "can't get descriptor\n");
> if (first)
> - list_splice_init(&first->descs_list, &atchan->free_descs_list);
> + list_splice_tail_init(&first->descs_list,
> + &atchan->free_descs_list);
> spin_unlock_irqrestore(&atchan->lock, irqflags);
> return NULL;
> }
> @@ -1051,8 +1053,8 @@ at_xdmac_prep_interleaved(struct dma_chan *chan,
> src_addr, dst_addr,
> xt, chunk);
> if (!desc) {
> - list_splice_init(&first->descs_list,
> - &atchan->free_descs_list);
> + list_splice_tail_init(&first->descs_list,
> + &atchan->free_descs_list);
> return NULL;
> }
>
> @@ -1132,7 +1134,8 @@ at_xdmac_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
> if (!desc) {
> dev_err(chan2dev(chan), "can't get descriptor\n");
> if (first)
> - list_splice_init(&first->descs_list, &atchan->free_descs_list);
> + list_splice_tail_init(&first->descs_list,
> + &atchan->free_descs_list);
> return NULL;
> }
>
> @@ -1308,8 +1311,8 @@ at_xdmac_prep_dma_memset_sg(struct dma_chan *chan, struct scatterlist *sgl,
> sg_dma_len(sg),
> value);
> if (!desc && first)
> - list_splice_init(&first->descs_list,
> - &atchan->free_descs_list);
> + list_splice_tail_init(&first->descs_list,
> + &atchan->free_descs_list);
>
> if (!first)
> first = desc;
> @@ -1701,7 +1704,8 @@ static void at_xdmac_tasklet(struct tasklet_struct *t)
>
> spin_lock_irq(&atchan->lock);
> /* Move the xfer descriptors into the free descriptors list. */
> - list_splice_init(&desc->descs_list, &atchan->free_descs_list);
> + list_splice_tail_init(&desc->descs_list,
> + &atchan->free_descs_list);
> at_xdmac_advance_work(atchan);
> spin_unlock_irq(&atchan->lock);
> }
> @@ -1850,7 +1854,8 @@ static int at_xdmac_device_terminate_all(struct dma_chan *chan)
> /* Cancel all pending transfers. */
> list_for_each_entry_safe(desc, _desc, &atchan->xfers_list, xfer_node) {
> list_del(&desc->xfer_node);
> - list_splice_init(&desc->descs_list, &atchan->free_descs_list);
> + list_splice_tail_init(&desc->descs_list,
> + &atchan->free_descs_list);
> }
>
> clear_bit(AT_XDMAC_CHAN_IS_PAUSED, &atchan->status);
> --
> 2.25.1
--
~Vinod
