diff mbox series

[2/7] drm/msm/dpu: drop dpu_encoder_early_unregister

Message ID 20230430235732.3341119-3-dmitry.baryshkov@linaro.org
State New
Headers show
Series drm/msm/dpu: simplify DPU encoder init | expand

Commit Message

Dmitry Baryshkov April 30, 2023, 11:57 p.m. UTC
There is no need to clean up debugfs manually, it will be done by the
DRM core on device deregistration.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
---
 drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c | 8 --------
 1 file changed, 8 deletions(-)

Comments

Abhinav Kumar May 2, 2023, 8:45 p.m. UTC | #1
On 4/30/2023 4:57 PM, Dmitry Baryshkov wrote:
> There is no need to clean up debugfs manually, it will be done by the
> DRM core on device deregistration.
> 
> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
> ---

There are two reasons to have the debugfs removed in the early_unregister:

1) Today, registration happens in late_register(), hence to balance the 
the call in _dpu_encoder_init_debugfs(), this one is present.

2) In drm_modeset_register_all(), if drm_connector_register_all() fails, 
it calls drm_encoder_unregister_all() first which calls early_unregister().

So to balance these out, dont we need to keep it?

>   drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c | 8 --------
>   1 file changed, 8 deletions(-)
> 
> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
> index 32785cb1b079..8c45c949ec39 100644
> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
> @@ -2154,13 +2154,6 @@ static int dpu_encoder_late_register(struct drm_encoder *encoder)
>   	return _dpu_encoder_init_debugfs(encoder);
>   }
>   
> -static void dpu_encoder_early_unregister(struct drm_encoder *encoder)
> -{
> -	struct dpu_encoder_virt *dpu_enc = to_dpu_encoder_virt(encoder);
> -
> -	debugfs_remove_recursive(dpu_enc->debugfs_root);
> -}
> -
>   static int dpu_encoder_virt_add_phys_encs(
>   		struct msm_display_info *disp_info,
>   		struct dpu_encoder_virt *dpu_enc,
> @@ -2374,7 +2367,6 @@ static const struct drm_encoder_helper_funcs dpu_encoder_helper_funcs = {
>   static const struct drm_encoder_funcs dpu_encoder_funcs = {
>   		.destroy = dpu_encoder_destroy,
>   		.late_register = dpu_encoder_late_register,
> -		.early_unregister = dpu_encoder_early_unregister,
>   };
>   
>   struct drm_encoder *dpu_encoder_init(struct drm_device *dev,
Dmitry Baryshkov May 2, 2023, 8:54 p.m. UTC | #2
On Tue, 2 May 2023 at 23:45, Abhinav Kumar <quic_abhinavk@quicinc.com> wrote:
>
>
>
> On 4/30/2023 4:57 PM, Dmitry Baryshkov wrote:
> > There is no need to clean up debugfs manually, it will be done by the
> > DRM core on device deregistration.
> >
> > Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
> > ---
>
> There are two reasons to have the debugfs removed in the early_unregister:
>
> 1) Today, registration happens in late_register(), hence to balance the
> the call in _dpu_encoder_init_debugfs(), this one is present.
>
> 2) In drm_modeset_register_all(), if drm_connector_register_all() fails,
> it calls drm_encoder_unregister_all() first which calls early_unregister().
>
> So to balance these out, dont we need to keep it?

Please correct me if I'm wrong, drm_debugfs_cleanup() should take care of that.

> >   drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c | 8 --------
> >   1 file changed, 8 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
> > index 32785cb1b079..8c45c949ec39 100644
> > --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
> > +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
> > @@ -2154,13 +2154,6 @@ static int dpu_encoder_late_register(struct drm_encoder *encoder)
> >       return _dpu_encoder_init_debugfs(encoder);
> >   }
> >
> > -static void dpu_encoder_early_unregister(struct drm_encoder *encoder)
> > -{
> > -     struct dpu_encoder_virt *dpu_enc = to_dpu_encoder_virt(encoder);
> > -
> > -     debugfs_remove_recursive(dpu_enc->debugfs_root);
> > -}
> > -
> >   static int dpu_encoder_virt_add_phys_encs(
> >               struct msm_display_info *disp_info,
> >               struct dpu_encoder_virt *dpu_enc,
> > @@ -2374,7 +2367,6 @@ static const struct drm_encoder_helper_funcs dpu_encoder_helper_funcs = {
> >   static const struct drm_encoder_funcs dpu_encoder_funcs = {
> >               .destroy = dpu_encoder_destroy,
> >               .late_register = dpu_encoder_late_register,
> > -             .early_unregister = dpu_encoder_early_unregister,
> >   };
> >
> >   struct drm_encoder *dpu_encoder_init(struct drm_device *dev,
Abhinav Kumar May 2, 2023, 8:59 p.m. UTC | #3
On 5/2/2023 1:54 PM, Dmitry Baryshkov wrote:
> On Tue, 2 May 2023 at 23:45, Abhinav Kumar <quic_abhinavk@quicinc.com> wrote:
>>
>>
>>
>> On 4/30/2023 4:57 PM, Dmitry Baryshkov wrote:
>>> There is no need to clean up debugfs manually, it will be done by the
>>> DRM core on device deregistration.
>>>
>>> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
>>> ---
>>
>> There are two reasons to have the debugfs removed in the early_unregister:
>>
>> 1) Today, registration happens in late_register(), hence to balance the
>> the call in _dpu_encoder_init_debugfs(), this one is present.
>>
>> 2) In drm_modeset_register_all(), if drm_connector_register_all() fails,
>> it calls drm_encoder_unregister_all() first which calls early_unregister().
>>
>> So to balance these out, dont we need to keep it?
> 
> Please correct me if I'm wrong, drm_debugfs_cleanup() should take care of that.
> 

Not from what I am seeing, drm_debugfs_cleanup() is getting called from 
the error handling path of drm_dev_register() and separately from 
drm_dev_unregister() but not from the error handling path of 
drm_modeset_register_all().

So that case will be unbalanced with this change.

>>>    drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c | 8 --------
>>>    1 file changed, 8 deletions(-)
>>>
>>> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
>>> index 32785cb1b079..8c45c949ec39 100644
>>> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
>>> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
>>> @@ -2154,13 +2154,6 @@ static int dpu_encoder_late_register(struct drm_encoder *encoder)
>>>        return _dpu_encoder_init_debugfs(encoder);
>>>    }
>>>
>>> -static void dpu_encoder_early_unregister(struct drm_encoder *encoder)
>>> -{
>>> -     struct dpu_encoder_virt *dpu_enc = to_dpu_encoder_virt(encoder);
>>> -
>>> -     debugfs_remove_recursive(dpu_enc->debugfs_root);
>>> -}
>>> -
>>>    static int dpu_encoder_virt_add_phys_encs(
>>>                struct msm_display_info *disp_info,
>>>                struct dpu_encoder_virt *dpu_enc,
>>> @@ -2374,7 +2367,6 @@ static const struct drm_encoder_helper_funcs dpu_encoder_helper_funcs = {
>>>    static const struct drm_encoder_funcs dpu_encoder_funcs = {
>>>                .destroy = dpu_encoder_destroy,
>>>                .late_register = dpu_encoder_late_register,
>>> -             .early_unregister = dpu_encoder_early_unregister,
>>>    };
>>>
>>>    struct drm_encoder *dpu_encoder_init(struct drm_device *dev,
>
Dmitry Baryshkov May 2, 2023, 9:04 p.m. UTC | #4
On 02/05/2023 23:59, Abhinav Kumar wrote:
> 
> 
> On 5/2/2023 1:54 PM, Dmitry Baryshkov wrote:
>> On Tue, 2 May 2023 at 23:45, Abhinav Kumar <quic_abhinavk@quicinc.com> 
>> wrote:
>>>
>>>
>>>
>>> On 4/30/2023 4:57 PM, Dmitry Baryshkov wrote:
>>>> There is no need to clean up debugfs manually, it will be done by the
>>>> DRM core on device deregistration.
>>>>
>>>> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
>>>> ---
>>>
>>> There are two reasons to have the debugfs removed in the 
>>> early_unregister:
>>>
>>> 1) Today, registration happens in late_register(), hence to balance the
>>> the call in _dpu_encoder_init_debugfs(), this one is present.
>>>
>>> 2) In drm_modeset_register_all(), if drm_connector_register_all() fails,
>>> it calls drm_encoder_unregister_all() first which calls 
>>> early_unregister().
>>>
>>> So to balance these out, dont we need to keep it?
>>
>> Please correct me if I'm wrong, drm_debugfs_cleanup() should take care 
>> of that.
>>
> 
> Not from what I am seeing, drm_debugfs_cleanup() is getting called from 
> the error handling path of drm_dev_register() and separately from 
> drm_dev_unregister() but not from the error handling path of 
> drm_modeset_register_all().
> 
> So that case will be unbalanced with this change.

But for the practical reasons the drm_modeset_register_all() can not 
fail. But I see your point. I'll check why drm_dev_register() doesn't 
respect an error return from drm_modeset_register_all(). Until that 
point we can drop this patch.

> 
>>>>    drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c | 8 --------
>>>>    1 file changed, 8 deletions(-)
>>>>
>>>> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c 
>>>> b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
>>>> index 32785cb1b079..8c45c949ec39 100644
>>>> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
>>>> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
>>>> @@ -2154,13 +2154,6 @@ static int dpu_encoder_late_register(struct 
>>>> drm_encoder *encoder)
>>>>        return _dpu_encoder_init_debugfs(encoder);
>>>>    }
>>>>
>>>> -static void dpu_encoder_early_unregister(struct drm_encoder *encoder)
>>>> -{
>>>> -     struct dpu_encoder_virt *dpu_enc = to_dpu_encoder_virt(encoder);
>>>> -
>>>> -     debugfs_remove_recursive(dpu_enc->debugfs_root);
>>>> -}
>>>> -
>>>>    static int dpu_encoder_virt_add_phys_encs(
>>>>                struct msm_display_info *disp_info,
>>>>                struct dpu_encoder_virt *dpu_enc,
>>>> @@ -2374,7 +2367,6 @@ static const struct drm_encoder_helper_funcs 
>>>> dpu_encoder_helper_funcs = {
>>>>    static const struct drm_encoder_funcs dpu_encoder_funcs = {
>>>>                .destroy = dpu_encoder_destroy,
>>>>                .late_register = dpu_encoder_late_register,
>>>> -             .early_unregister = dpu_encoder_early_unregister,
>>>>    };
>>>>
>>>>    struct drm_encoder *dpu_encoder_init(struct drm_device *dev,
>>
diff mbox series

Patch

diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
index 32785cb1b079..8c45c949ec39 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
@@ -2154,13 +2154,6 @@  static int dpu_encoder_late_register(struct drm_encoder *encoder)
 	return _dpu_encoder_init_debugfs(encoder);
 }
 
-static void dpu_encoder_early_unregister(struct drm_encoder *encoder)
-{
-	struct dpu_encoder_virt *dpu_enc = to_dpu_encoder_virt(encoder);
-
-	debugfs_remove_recursive(dpu_enc->debugfs_root);
-}
-
 static int dpu_encoder_virt_add_phys_encs(
 		struct msm_display_info *disp_info,
 		struct dpu_encoder_virt *dpu_enc,
@@ -2374,7 +2367,6 @@  static const struct drm_encoder_helper_funcs dpu_encoder_helper_funcs = {
 static const struct drm_encoder_funcs dpu_encoder_funcs = {
 		.destroy = dpu_encoder_destroy,
 		.late_register = dpu_encoder_late_register,
-		.early_unregister = dpu_encoder_early_unregister,
 };
 
 struct drm_encoder *dpu_encoder_init(struct drm_device *dev,