Re: [PATCH] RDMA/hns: Use dma_alloc_coherent() instead of kmalloc/dma_map_single()

[Cai Huoqing <caihuoqing@baidu.com>]

On 09 10月 21 17:50:50, Wenpeng Liang wrote:
> 
> 
> On 2021/10/5 3:52, Jason Gunthorpe wrote:
> > On Mon, Sep 27, 2021 at 08:59:13AM -0300, Jason Gunthorpe wrote:
> >> On Sun, Sep 26, 2021 at 02:11:15PM +0800, Cai Huoqing wrote:
> >>> Replacing kmalloc/kfree/dma_map_single/dma_unmap_single()
> >>> with dma_alloc_coherent/dma_free_coherent() helps to reduce
> >>> code size, and simplify the code, and coherent DMA will not
> >>> clear the cache every time.
> >>>
> >>> Signed-off-by: Cai Huoqing <caihuoqing@baidu.com>
> >>>  drivers/infiniband/hw/hns/hns_roce_hw_v2.c | 20 +++++---------------
> >>>  1 file changed, 5 insertions(+), 15 deletions(-)
> >>
> >> Given I don't see any dma_sync_single calls for this mapping, isn't
> >> this a correctness fix too?
> > 
> > HNS folks?
> > 
> > Jason
> > .
> > 
> 
> Our SoC can keep cache coherent, so there is no exception even if
> dma_sync_single* is not called, but the driver should not make
> assumptions about SoC.
> 
> So using dma_alloc_coherent() instead of kmalloc/dma_map_single()
> can simplify the code and achieve the same purpose.
> 
> Wenpeng Liang


Hi Liang

Thanks for your feedback.

If you think my patch is correct, you can give a Reviewed-by: to it.
You can also give a Tested-by: to it, if the test on hardware was made.

Thanks
Cai