[PATCH] drm/amdkfd: Select PCI_P2PDMA and DMABUF_MOVE_NOTIFY instead of depending

[Errabolu, Ramesh]

[Public]

Follow the dependency chain of either CONFIG_DMABUF_MOVE_NOTIFY or CONFIG_PCI_P2PDMA.

What happens if you enable CONFIG_DMABUF_MOVE_NOTIFY but its dependency CONFIG_DMA_SHARED_BUFFER is not enabled.

Therefore using "selects" is not the right way to go about it.

Regards,
Ramesh

-----Original Message-----
From: Limonciello, Mario <Mario.Limonciello at amd.com> 
Sent: Thursday, July 7, 2022 3:34 PM
To: Errabolu, Ramesh <Ramesh.Errabolu at amd.com>; amd-gfx at lists.freedesktop.org; Kuehling, Felix <Felix.Kuehling at amd.com>
Subject: RE: [PATCH] drm/amdkfd: Select PCI_P2PDMA and DMABUF_MOVE_NOTIFY instead of depending

[Public]

> -----Original Message-----
> From: Errabolu, Ramesh <Ramesh.Errabolu at amd.com>
> Sent: Thursday, July 7, 2022 15:30
> To: Limonciello, Mario <Mario.Limonciello at amd.com>; amd- 
> gfx at lists.freedesktop.org; Kuehling, Felix <Felix.Kuehling at amd.com>
> Cc: Limonciello, Mario <Mario.Limonciello at amd.com>
> Subject: RE: [PATCH] drm/amdkfd: Select PCI_P2PDMA and 
> DMABUF_MOVE_NOTIFY instead of depending
> 
> [AMD Official Use Only - General]
> 
> Using "depends" prevents shallow binding. Applying "select" can cause trouble.

Can you give some more information?  What kind of trouble can be caused?

> 
> Regards,
> Ramesh
> 
> -----Original Message-----
> From: amd-gfx <amd-gfx-bounces at lists.freedesktop.org> On Behalf Of 
> Mario Limonciello
> Sent: Thursday, July 7, 2022 3:12 PM
> To: amd-gfx at lists.freedesktop.org; Kuehling, Felix 
> <Felix.Kuehling at amd.com>
> Cc: Limonciello, Mario <Mario.Limonciello at amd.com>
> Subject: [PATCH] drm/amdkfd: Select PCI_P2PDMA and DMABUF_MOVE_NOTIFY 
> instead of depending
> 
> [CAUTION: External Email]
> 
> By having dependencies on PCI_P2PDMA and DMABUF_MOVE_NOTIFY the option 
> HSA_AMD_P2P is not discoverable.  The kernel menu configuration hides 
> it if the dependencies aren't satisfied, making it harder to find.
> 
> Instead select these options when enabling HSA_AMD_P2P.  This way 
> distributions and users can just enable HSA_AMD_P2P.
> 
> Signed-off-by: Mario Limonciello <mario.limonciello at amd.com>
> ---
>  drivers/gpu/drm/amd/amdkfd/Kconfig | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/amd/amdkfd/Kconfig
> b/drivers/gpu/drm/amd/amdkfd/Kconfig
> index 93bd4eda0d94..b153c26903ee 100644
> --- a/drivers/gpu/drm/amd/amdkfd/Kconfig
> +++ b/drivers/gpu/drm/amd/amdkfd/Kconfig
> @@ -28,7 +28,9 @@ config HSA_AMD_SVM
> 
>  config HSA_AMD_P2P
>         bool "HSA kernel driver support for peer-to-peer for AMD GPU devices"
> -       depends on HSA_AMD && PCI_P2PDMA && DMABUF_MOVE_NOTIFY
> +       depends on HSA_AMD
> +       select PCI_P2PDMA
> +       select DMABUF_MOVE_NOTIFY
>         help
>           Enable peer-to-peer (P2P) communication between AMD GPUs over
>           the PCIe bus. This can improve performance of multi-GPU 
> compute
> --
> 2.34.1