From: Roland Dreier Date: Mon, 30 Mar 2009 15:31:05 +0000 (-0700) Subject: IB/mlx4: Use pgprot_writecombine() for BlueFlame pages X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=e1d60ec6699f19b760df8261e922ae236ea7bb31;p=GitHub%2FLineageOS%2FG12%2Fandroid_kernel_amlogic_linux-4.9.git IB/mlx4: Use pgprot_writecombine() for BlueFlame pages The PAT work on x86 has finally made pgprot_writecombine() a usable API for modular drivers. As the comment indicates, this is exactly what we want to use in mlx4_ib to map BlueFlame pages up to userspace, since using WC for these pages improves small message latency significantly. Signed-off-by: Roland Dreier --- diff --git a/drivers/infiniband/hw/mlx4/main.c b/drivers/infiniband/hw/mlx4/main.c index 2ccb9d31771f..ae3d7590346e 100644 --- a/drivers/infiniband/hw/mlx4/main.c +++ b/drivers/infiniband/hw/mlx4/main.c @@ -394,8 +394,7 @@ static int mlx4_ib_mmap(struct ib_ucontext *context, struct vm_area_struct *vma) PAGE_SIZE, vma->vm_page_prot)) return -EAGAIN; } else if (vma->vm_pgoff == 1 && dev->dev->caps.bf_reg_size != 0) { - /* FIXME want pgprot_writecombine() for BlueFlame pages */ - vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); + vma->vm_page_prot = pgprot_writecombine(vma->vm_page_prot); if (io_remap_pfn_range(vma, vma->vm_start, to_mucontext(context)->uar.pfn +