On Mon, Nov 14, 2016 at 04:36:32PM -0700, Dave Jiang wrote:
> Existing implementation does not honor the alignment restrictions imposed
> by the DMA engines. Allocate buffers with built in slack for honoring
> alignment restrictions. Creating new arrays to hold the aligned pointers
> and use those pointers for operations.
>
> Signed-off-by: Dave Jiang <dave.jiang@xxxxxxxxx>
> ---
> drivers/dma/dmatest.c | 57 ++++++++++++++++++++++++++++++++-----------------
> 1 file changed, 37 insertions(+), 20 deletions(-)
>
> diff --git a/drivers/dma/dmatest.c b/drivers/dma/dmatest.c
> index cf76fc6..65c2ee0 100644
> --- a/drivers/dma/dmatest.c
> +++ b/drivers/dma/dmatest.c
> @@ -164,7 +164,9 @@ struct dmatest_thread {
> struct task_struct *task;
> struct dma_chan *chan;
> u8 **srcs;
> + u8 **usrcs;
> u8 **dsts;
> + u8 **udsts;
> enum dma_transaction_type type;
> bool done;
> };
> @@ -431,6 +433,7 @@ static int dmatest_func(void *data)
> ktime_t comparetime = ktime_set(0, 0);
> s64 runtime = 0;
> unsigned long long total_len = 0;
> + u8 align = 0;
>
> set_freezable();
>
> @@ -441,18 +444,22 @@ static int dmatest_func(void *data)
> params = &info->params;
> chan = thread->chan;
> dev = chan->device;
> - if (thread->type == DMA_MEMCPY)
> + if (thread->type == DMA_MEMCPY) {
> + align = dev->copy_align;
> src_cnt = dst_cnt = 1;
> - else if (thread->type == DMA_SG)
> + } else if (thread->type == DMA_SG) {
> + align = dev->copy_align;
> src_cnt = dst_cnt = sg_buffers;
> - else if (thread->type == DMA_XOR) {
> + } else if (thread->type == DMA_XOR) {
> /* force odd to ensure dst = src */
> src_cnt = min_odd(params->xor_sources | 1, dev->max_xor);
> dst_cnt = 1;
> + align = dev->xor_align;
> } else if (thread->type == DMA_PQ) {
> /* force odd to ensure dst = src */
> src_cnt = min_odd(params->pq_sources | 1, dma_maxpq(dev, 0));
> dst_cnt = 2;
> + align = dev->pq_align;
>
> pq_coefs = kmalloc(params->pq_sources+1, GFP_KERNEL);
> if (!pq_coefs)
> @@ -466,20 +473,35 @@ static int dmatest_func(void *data)
> thread->srcs = kcalloc(src_cnt+1, sizeof(u8 *), GFP_KERNEL);
> if (!thread->srcs)
> goto err_srcs;
> +
> + thread->usrcs = kcalloc(src_cnt+1, sizeof(u8 *), GFP_KERNEL);
spaces around + pls, here and other places
> + if (!thread->usrcs)
> + goto err_usrcs;
> +
> for (i = 0; i < src_cnt; i++) {
> - thread->srcs[i] = kmalloc(params->buf_size, GFP_KERNEL);
> - if (!thread->srcs[i])
> + thread->usrcs[i] = kmalloc(params->buf_size+align, GFP_KERNEL);
> + if (!thread->usrcs[i])
> goto err_srcbuf;
> + /* align srcs to alignment restriction */
> + thread->srcs[i] = align ?
> + PTR_ALIGN(thread->usrcs[i], align) : thread->usrcs[i];
if-else would look more readable
--
~Vinod
--
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