Re: [PATCH] cma: decrease CMA_ALIGNMENT lower limit to 2

2020-10-05 Thread Christoph Hellwig
Thanks,

applied to dma-mapping for-next.
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[PATCH] cma: decrease CMA_ALIGNMENT lower limit to 2

2020-09-30 Thread Paul Cercueil
On an embedded system with a tiny (1 MiB) CMA area for video memory, and
a simple enough video pipeline, we can decrease the CMA_ALIGNMENT by a
factor of 2 to avoid wasting memory, as all the allocations for video
buffers will be of the exact same size (dictated by the size of the
screen).

Signed-off-by: Paul Cercueil 
---
 kernel/dma/Kconfig | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/dma/Kconfig b/kernel/dma/Kconfig
index 847a9d1fa634..f15e782e19ca 100644
--- a/kernel/dma/Kconfig
+++ b/kernel/dma/Kconfig
@@ -162,7 +162,7 @@ endchoice
 
 config CMA_ALIGNMENT
int "Maximum PAGE_SIZE order of alignment for contiguous buffers"
-   range 4 12
+   range 2 12
default 8
help
  DMA mapping framework by default aligns all buffers to the smallest
-- 
2.28.0

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