From: Douglas Anderson <dianders@xxxxxxxxxxxx> We do video allocation all the time and we need it to be fast. Plus TLB efficiency isn't terribly important for video. That means we want to set DMA_ATTR_ALLOC_SINGLE_PAGES. See also the previous change (commit 14d3ae2efeed "ARM: dma-mapping: Use DMA_ATTR_ALLOC_SINGLE_PAGES hint to optimize allocation"). Signed-off-by: Douglas Anderson <dianders@xxxxxxxxxxxx> [mszyprow: rebased patch onto v4.9-rc1 and adapted changes to latest videbuf2 changes, this simplifies code changes to only set proper dma attribute flag and comment the reason for it, added commit id of arch/arm/mm patch] Signed-off-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx> --- drivers/media/platform/s5p-mfc/s5p_mfc.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/drivers/media/platform/s5p-mfc/s5p_mfc.c b/drivers/media/platform/s5p-mfc/s5p_mfc.c index 27b375e75555..a0a29194ccd1 100644 --- a/drivers/media/platform/s5p-mfc/s5p_mfc.c +++ b/drivers/media/platform/s5p-mfc/s5p_mfc.c @@ -851,6 +851,11 @@ static int s5p_mfc_open(struct file *file) ret = -ENOENT; goto err_queue_init; } + /* + * We'll do mostly sequential access, so sacrifice TLB efficiency for + * faster allocation. + */ + q->dma_attrs = DMA_ATTR_ALLOC_SINGLE_PAGES; q->mem_ops = &vb2_dma_contig_memops; q->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_COPY; ret = vb2_queue_init(q); @@ -881,6 +886,12 @@ static int s5p_mfc_open(struct file *file) * will keep the value of bytesused intact. */ q->allow_zero_bytesused = 1; + + /* + * We'll do mostly sequential access, so sacrifice TLB efficiency for + * faster allocation. + */ + q->dma_attrs = DMA_ATTR_ALLOC_SINGLE_PAGES; q->mem_ops = &vb2_dma_contig_memops; q->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_COPY; ret = vb2_queue_init(q); -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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