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Date:   Thu, 23 Nov 2023 08:24:24 +0800
From:   Zhenyu Wang <zhenyuw@linux.intel.com>
To:     Christian Brauner <brauner@kernel.org>
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Subject: Re: [PATCH v2 1/4] i915: make inject_virtual_interrupt() void
Message-ID: <ZV6buHrQy2+CJ7xX@debian-scheme>
Reply-To: Zhenyu Wang <zhenyuw@linux.intel.com>
References: <20231122-vfs-eventfd-signal-v2-0-bd549b14ce0c@kernel.org>
 <20231122-vfs-eventfd-signal-v2-1-bd549b14ce0c@kernel.org>
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On 2023.11.22 13:48:22 +0100, Christian Brauner wrote:
> The single caller of inject_virtual_interrupt() ignores the return value
> anyway. This allows us to simplify eventfd_signal() in follow-up
> patches.
>=20
> Signed-off-by: Christian Brauner <brauner@kernel.org>
> ---
>  drivers/gpu/drm/i915/gvt/interrupt.c | 14 +++++++-------
>  1 file changed, 7 insertions(+), 7 deletions(-)
>=20
> diff --git a/drivers/gpu/drm/i915/gvt/interrupt.c b/drivers/gpu/drm/i915/=
gvt/interrupt.c
> index de3f5903d1a7..9665876b4b13 100644
> --- a/drivers/gpu/drm/i915/gvt/interrupt.c
> +++ b/drivers/gpu/drm/i915/gvt/interrupt.c
> @@ -422,7 +422,7 @@ static void init_irq_map(struct intel_gvt_irq *irq)
>  #define MSI_CAP_DATA(offset) (offset + 8)
>  #define MSI_CAP_EN 0x1
> =20
> -static int inject_virtual_interrupt(struct intel_vgpu *vgpu)
> +static void inject_virtual_interrupt(struct intel_vgpu *vgpu)
>  {
>  	unsigned long offset =3D vgpu->gvt->device_info.msi_cap_offset;
>  	u16 control, data;
> @@ -434,10 +434,10 @@ static int inject_virtual_interrupt(struct intel_vg=
pu *vgpu)
> =20
>  	/* Do not generate MSI if MSIEN is disabled */
>  	if (!(control & MSI_CAP_EN))
> -		return 0;
> +		return;
> =20
>  	if (WARN(control & GENMASK(15, 1), "only support one MSI format\n"))
> -		return -EINVAL;
> +		return;
> =20
>  	trace_inject_msi(vgpu->id, addr, data);
> =20
> @@ -451,10 +451,10 @@ static int inject_virtual_interrupt(struct intel_vg=
pu *vgpu)
>  	 * returned and don't inject interrupt into guest.
>  	 */
>  	if (!test_bit(INTEL_VGPU_STATUS_ATTACHED, vgpu->status))
> -		return -ESRCH;
> -	if (vgpu->msi_trigger && eventfd_signal(vgpu->msi_trigger, 1) !=3D 1)
> -		return -EFAULT;
> -	return 0;
> +		return;
> +	if (!vgpu->msi_trigger)
> +		return;
> +	eventfd_signal(vgpu->msi_trigger, 1);
>  }

I think it's a little simpler to write as
    if (vgpu->msi_trigger)
            eventfd_signal(vgpu->msi_trigger, 1);

Looks fine with me.

Reviewed-by: Zhenyu Wang <zhenyuw@linux.intel.com>

Thanks!

> =20
>  static void propagate_event(struct intel_gvt_irq *irq,
>=20
> --=20
> 2.42.0
>=20

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