[PATCH] drm/i915/fbc: Avoid full proxy f_ops for FBC debug attributes

[PATCH] drm/i915/fbc: Avoid full proxy f_ops for FBC debug attributes

[Deepak R Varma]

Using DEFINE_SIMPLE_ATTRIBUTE macro with the debugfs_create_file()
function adds the overhead of introducing a proxy file operation
functions to wrap the original read/write inside file removal protection
functions. This adds significant overhead in terms of introducing and
managing the proxy factory file operations structure and function
wrapping at runtime.
As a replacement, a combination of DEFINE_DEBUGFS_ATTRIBUTE macro paired
with debugfs_create_file_unsafe() is suggested to be used instead.  The
DEFINE_DEBUGFS_ATTRIBUTE utilises debugfs_file_get() and
debugfs_file_put() wrappers to protect the original read and write
function calls for the debug attributes. There is no need for any
runtime proxy file operations to be managed by the debugfs core.

This Change is reported by the debugfs_simple_attr.cocci Coccinelle
semantic patch.

Signed-off-by: Deepak R Varma <drv@mailo.com>
---
 drivers/gpu/drm/i915/display/intel_fbc.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_fbc.c b/drivers/gpu/drm/i915/display/intel_fbc.c
index b5ee5ea0d010..4b481e2f908b 100644
--- a/drivers/gpu/drm/i915/display/intel_fbc.c
+++ b/drivers/gpu/drm/i915/display/intel_fbc.c
@@ -1809,10 +1809,10 @@ static int intel_fbc_debugfs_false_color_set(void *data, u64 val)
 	return 0;
 }

-DEFINE_SIMPLE_ATTRIBUTE(intel_fbc_debugfs_false_color_fops,
-			intel_fbc_debugfs_false_color_get,
-			intel_fbc_debugfs_false_color_set,
-			"%llu\n");
+DEFINE_DEBUGFS_ATTRIBUTE(intel_fbc_debugfs_false_color_fops,
+			 intel_fbc_debugfs_false_color_get,
+			 intel_fbc_debugfs_false_color_set,
+			 "%llu\n");

 static void intel_fbc_debugfs_add(struct intel_fbc *fbc,
 				  struct dentry *parent)
@@ -1821,8 +1821,8 @@ static void intel_fbc_debugfs_add(struct intel_fbc *fbc,
 			    fbc, &intel_fbc_debugfs_status_fops);

 	if (fbc->funcs->set_false_color)
-		debugfs_create_file("i915_fbc_false_color", 0644, parent,
-				    fbc, &intel_fbc_debugfs_false_color_fops);
+		debugfs_create_file_unsafe("i915_fbc_false_color", 0644, parent,
+					   fbc, &intel_fbc_debugfs_false_color_fops);
 }

 void intel_fbc_crtc_debugfs_add(struct intel_crtc *crtc)
--
2.34.1

Re: [PATCH] drm/i915/fbc: Avoid full proxy f_ops for FBC debug attributes

[Rodrigo Vivi]

On Tue, Dec 27, 2022 at 01:30:53PM +0530, Deepak R Varma wrote:
> Using DEFINE_SIMPLE_ATTRIBUTE macro with the debugfs_create_file()
> function adds the overhead of introducing a proxy file operation
> functions to wrap the original read/write inside file removal protection
> functions. This adds significant overhead in terms of introducing and
> managing the proxy factory file operations structure and function
> wrapping at runtime.
> As a replacement, a combination of DEFINE_DEBUGFS_ATTRIBUTE macro paired
> with debugfs_create_file_unsafe() is suggested to be used instead.  The
> DEFINE_DEBUGFS_ATTRIBUTE utilises debugfs_file_get() and
> debugfs_file_put() wrappers to protect the original read and write
> function calls for the debug attributes. There is no need for any
> runtime proxy file operations to be managed by the debugfs core.
> 
> This Change is reported by the debugfs_simple_attr.cocci Coccinelle
> semantic patch.

I just checked here with
$ make coccicheck M=drivers/gpu/drm/i915/ MODE=context COCCI=./scripts/coccinelle/api/debugfs/debugfs_simple_attr.cocci

The part reported by the this script is the s/SIMPLE/DEBUGFS
but the change to the unsafe option is not.

This commit message is not explaining why the unsafe is the suggested
or who suggested it.

If you remove the unsafe part feel free to resend adding:

Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
(to both patches, this and the drrs one.

Also, it looks like you could contribute with other 2 patches:
drivers/gpu/drm/i915/pxp/intel_pxp_debugfs.c:64:0-23: WARNING: pxp_terminate_fops should be defined with DEFINE_DEBUGFS_ATTRIBUTE
drivers/gpu/drm/i915/gvt/debugfs.c:150:0-23: WARNING: vgpu_scan_nonprivbb_fops should be defined with DEFINE_DEBUGFS_ATTRIBUTE

> 
> Signed-off-by: Deepak R Varma <drv@mailo.com>
> ---
>  drivers/gpu/drm/i915/display/intel_fbc.c | 12 ++++++------
>  1 file changed, 6 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_fbc.c b/drivers/gpu/drm/i915/display/intel_fbc.c
> index b5ee5ea0d010..4b481e2f908b 100644
> --- a/drivers/gpu/drm/i915/display/intel_fbc.c
> +++ b/drivers/gpu/drm/i915/display/intel_fbc.c
> @@ -1809,10 +1809,10 @@ static int intel_fbc_debugfs_false_color_set(void *data, u64 val)
>  	return 0;
>  }
> 
> -DEFINE_SIMPLE_ATTRIBUTE(intel_fbc_debugfs_false_color_fops,
> -			intel_fbc_debugfs_false_color_get,
> -			intel_fbc_debugfs_false_color_set,
> -			"%llu\n");
> +DEFINE_DEBUGFS_ATTRIBUTE(intel_fbc_debugfs_false_color_fops,
> +			 intel_fbc_debugfs_false_color_get,
> +			 intel_fbc_debugfs_false_color_set,
> +			 "%llu\n");
> 
>  static void intel_fbc_debugfs_add(struct intel_fbc *fbc,
>  				  struct dentry *parent)
> @@ -1821,8 +1821,8 @@ static void intel_fbc_debugfs_add(struct intel_fbc *fbc,
>  			    fbc, &intel_fbc_debugfs_status_fops);
> 
>  	if (fbc->funcs->set_false_color)
> -		debugfs_create_file("i915_fbc_false_color", 0644, parent,
> -				    fbc, &intel_fbc_debugfs_false_color_fops);
> +		debugfs_create_file_unsafe("i915_fbc_false_color", 0644, parent,
> +					   fbc, &intel_fbc_debugfs_false_color_fops);
>  }
> 
>  void intel_fbc_crtc_debugfs_add(struct intel_crtc *crtc)
> --
> 2.34.1
> 
> 
> 

Re: [PATCH] drm/i915/fbc: Avoid full proxy f_ops for FBC debug attributes

[Deepak R Varma]

On Tue, Dec 27, 2022 at 12:13:56PM -0500, Rodrigo Vivi wrote:
> On Tue, Dec 27, 2022 at 01:30:53PM +0530, Deepak R Varma wrote:
> > Using DEFINE_SIMPLE_ATTRIBUTE macro with the debugfs_create_file()
> > function adds the overhead of introducing a proxy file operation
> > functions to wrap the original read/write inside file removal protection
> > functions. This adds significant overhead in terms of introducing and
> > managing the proxy factory file operations structure and function
> > wrapping at runtime.
> > As a replacement, a combination of DEFINE_DEBUGFS_ATTRIBUTE macro paired
> > with debugfs_create_file_unsafe() is suggested to be used instead.  The
> > DEFINE_DEBUGFS_ATTRIBUTE utilises debugfs_file_get() and
> > debugfs_file_put() wrappers to protect the original read and write
> > function calls for the debug attributes. There is no need for any
> > runtime proxy file operations to be managed by the debugfs core.
> >
> > This Change is reported by the debugfs_simple_attr.cocci Coccinelle
> > semantic patch.
>
> I just checked here with
> $ make coccicheck M=drivers/gpu/drm/i915/ MODE=context COCCI=./scripts/coccinelle/api/debugfs/debugfs_simple_attr.cocci

Hello Rodrigo,
Thank you so much for your review and feedback on the patch proposal.

>
> The part reported by the this script is the s/SIMPLE/DEBUGFS
> but the change to the unsafe option is not.

If you look at the original commit of this coccinelle file, it calls out the
need for pairing debugfs_create_file_unsafe() as well. Please review this

commitID: 5103068eaca2: ("debugfs, coccinelle: check for obsolete DEFINE_SIMPLE_ATTRIBUTE() usage")

Based on my review of the code, the functions debugfs_create_file() and
debugfs_create_file_unsafe(), both internally call __debugfs_create_file().
However, they pass debugfs_full_proxy_file_operations and
debugfs_open_proxy_file_operations respectively to it. The former represents the
full proxy factory, where as the later one is lightweight open proxy
implementation of the file operations structure.

>
> This commit message is not explaining why the unsafe is the suggested
> or who suggested it.

If you find the response above accurate, I will include these details about
the _unsafe() function in my commit message in v2.

>
> If you remove the unsafe part feel free to resend adding:

Please confirm you still believe switching to _unsafe() is not necessary.

>
> Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
> (to both patches, this and the drrs one.
>
> Also, it looks like you could contribute with other 2 patches:
> drivers/gpu/drm/i915/pxp/intel_pxp_debugfs.c:64:0-23: WARNING: pxp_terminate_fops should be defined with DEFINE_DEBUGFS_ATTRIBUTE
> drivers/gpu/drm/i915/gvt/debugfs.c:150:0-23: WARNING: vgpu_scan_nonprivbb_fops should be defined with DEFINE_DEBUGFS_ATTRIBUTE

Yes, these are on my list. Was waiting for a feedback on the first submission
before I send more similar patches.

Appreciate your time and the feedback.


Regards,
./drv

>
> >
> > Signed-off-by: Deepak R Varma <drv@mailo.com>
> > ---
> >  drivers/gpu/drm/i915/display/intel_fbc.c | 12 ++++++------
> >  1 file changed, 6 insertions(+), 6 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/i915/display/intel_fbc.c b/drivers/gpu/drm/i915/display/intel_fbc.c
> > index b5ee5ea0d010..4b481e2f908b 100644
> > --- a/drivers/gpu/drm/i915/display/intel_fbc.c
> > +++ b/drivers/gpu/drm/i915/display/intel_fbc.c
> > @@ -1809,10 +1809,10 @@ static int intel_fbc_debugfs_false_color_set(void *data, u64 val)
> >  	return 0;
> >  }
> >
> > -DEFINE_SIMPLE_ATTRIBUTE(intel_fbc_debugfs_false_color_fops,
> > -			intel_fbc_debugfs_false_color_get,
> > -			intel_fbc_debugfs_false_color_set,
> > -			"%llu\n");
> > +DEFINE_DEBUGFS_ATTRIBUTE(intel_fbc_debugfs_false_color_fops,
> > +			 intel_fbc_debugfs_false_color_get,
> > +			 intel_fbc_debugfs_false_color_set,
> > +			 "%llu\n");
> >
> >  static void intel_fbc_debugfs_add(struct intel_fbc *fbc,
> >  				  struct dentry *parent)
> > @@ -1821,8 +1821,8 @@ static void intel_fbc_debugfs_add(struct intel_fbc *fbc,
> >  			    fbc, &intel_fbc_debugfs_status_fops);
> >
> >  	if (fbc->funcs->set_false_color)
> > -		debugfs_create_file("i915_fbc_false_color", 0644, parent,
> > -				    fbc, &intel_fbc_debugfs_false_color_fops);
> > +		debugfs_create_file_unsafe("i915_fbc_false_color", 0644, parent,
> > +					   fbc, &intel_fbc_debugfs_false_color_fops);
> >  }
> >
> >  void intel_fbc_crtc_debugfs_add(struct intel_crtc *crtc)
> > --
> > 2.34.1
> >
> >
> >

Re: [PATCH] drm/i915/fbc: Avoid full proxy f_ops for FBC debug attributes

[Rodrigo Vivi]

On Tue, Dec 27, 2022 at 11:36:13PM +0530, Deepak R Varma wrote:
> On Tue, Dec 27, 2022 at 12:13:56PM -0500, Rodrigo Vivi wrote:
> > On Tue, Dec 27, 2022 at 01:30:53PM +0530, Deepak R Varma wrote:
> > > Using DEFINE_SIMPLE_ATTRIBUTE macro with the debugfs_create_file()
> > > function adds the overhead of introducing a proxy file operation
> > > functions to wrap the original read/write inside file removal protection
> > > functions. This adds significant overhead in terms of introducing and
> > > managing the proxy factory file operations structure and function
> > > wrapping at runtime.
> > > As a replacement, a combination of DEFINE_DEBUGFS_ATTRIBUTE macro paired
> > > with debugfs_create_file_unsafe() is suggested to be used instead.  The
> > > DEFINE_DEBUGFS_ATTRIBUTE utilises debugfs_file_get() and
> > > debugfs_file_put() wrappers to protect the original read and write
> > > function calls for the debug attributes. There is no need for any
> > > runtime proxy file operations to be managed by the debugfs core.
> > >
> > > This Change is reported by the debugfs_simple_attr.cocci Coccinelle
> > > semantic patch.
> >
> > I just checked here with
> > $ make coccicheck M=drivers/gpu/drm/i915/ MODE=context COCCI=./scripts/coccinelle/api/debugfs/debugfs_simple_attr.cocci
> 
> Hello Rodrigo,
> Thank you so much for your review and feedback on the patch proposal.
> 
> >
> > The part reported by the this script is the s/SIMPLE/DEBUGFS
> > but the change to the unsafe option is not.
> 
> If you look at the original commit of this coccinelle file, it calls out the
> need for pairing debugfs_create_file_unsafe() as well. Please review this
> 
> commitID: 5103068eaca2: ("debugfs, coccinelle: check for obsolete DEFINE_SIMPLE_ATTRIBUTE() usage")

+Nicolai and Julia.

It looks like coccinelle got right the
- DEFINE_SIMPLE_ATTRIBUTE(dsa_fops, dsa_get, dsa_set, dsa_fmt);
+ DEFINE_DEBUGFS_ATTRIBUTE(dsa_fops, dsa_get, dsa_set, dsa_fmt);

but it failed badly on
- debugfs_create_file(name, mode, parent, data, &dsa_fops)
+ debugfs_create_file_unsafe(name, mode, parent, data, &dsa_fops)

> 
> Based on my review of the code, the functions debugfs_create_file() and
> debugfs_create_file_unsafe(), both internally call __debugfs_create_file().
> However, they pass debugfs_full_proxy_file_operations and
> debugfs_open_proxy_file_operations respectively to it. The former represents the
> full proxy factory, where as the later one is lightweight open proxy
> implementation of the file operations structure.
> 
> >
> > This commit message is not explaining why the unsafe is the suggested
> > or who suggested it.
> 
> If you find the response above accurate, I will include these details about
> the _unsafe() function in my commit message in v2.
> 
> >
> > If you remove the unsafe part feel free to resend adding:
> 
> Please confirm you still believe switching to _unsafe() is not necessary.

Based on the coccinelle commit it looks like you are right, but cocinelle
just failed to detect the case. Let's see what Nicolai and Julia respond
before we move with any patch here.

> 
> >
> > Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
> > (to both patches, this and the drrs one.
> >
> > Also, it looks like you could contribute with other 2 patches:
> > drivers/gpu/drm/i915/pxp/intel_pxp_debugfs.c:64:0-23: WARNING: pxp_terminate_fops should be defined with DEFINE_DEBUGFS_ATTRIBUTE
> > drivers/gpu/drm/i915/gvt/debugfs.c:150:0-23: WARNING: vgpu_scan_nonprivbb_fops should be defined with DEFINE_DEBUGFS_ATTRIBUTE
> 
> Yes, these are on my list. Was waiting for a feedback on the first submission
> before I send more similar patches.
> 
> Appreciate your time and the feedback.
> 
> 
> Regards,
> ./drv
> 
> >
> > >
> > > Signed-off-by: Deepak R Varma <drv@mailo.com>
> > > ---
> > >  drivers/gpu/drm/i915/display/intel_fbc.c | 12 ++++++------
> > >  1 file changed, 6 insertions(+), 6 deletions(-)
> > >
> > > diff --git a/drivers/gpu/drm/i915/display/intel_fbc.c b/drivers/gpu/drm/i915/display/intel_fbc.c
> > > index b5ee5ea0d010..4b481e2f908b 100644
> > > --- a/drivers/gpu/drm/i915/display/intel_fbc.c
> > > +++ b/drivers/gpu/drm/i915/display/intel_fbc.c
> > > @@ -1809,10 +1809,10 @@ static int intel_fbc_debugfs_false_color_set(void *data, u64 val)
> > >  	return 0;
> > >  }
> > >
> > > -DEFINE_SIMPLE_ATTRIBUTE(intel_fbc_debugfs_false_color_fops,
> > > -			intel_fbc_debugfs_false_color_get,
> > > -			intel_fbc_debugfs_false_color_set,
> > > -			"%llu\n");
> > > +DEFINE_DEBUGFS_ATTRIBUTE(intel_fbc_debugfs_false_color_fops,
> > > +			 intel_fbc_debugfs_false_color_get,
> > > +			 intel_fbc_debugfs_false_color_set,
> > > +			 "%llu\n");
> > >
> > >  static void intel_fbc_debugfs_add(struct intel_fbc *fbc,
> > >  				  struct dentry *parent)
> > > @@ -1821,8 +1821,8 @@ static void intel_fbc_debugfs_add(struct intel_fbc *fbc,
> > >  			    fbc, &intel_fbc_debugfs_status_fops);
> > >
> > >  	if (fbc->funcs->set_false_color)
> > > -		debugfs_create_file("i915_fbc_false_color", 0644, parent,
> > > -				    fbc, &intel_fbc_debugfs_false_color_fops);
> > > +		debugfs_create_file_unsafe("i915_fbc_false_color", 0644, parent,
> > > +					   fbc, &intel_fbc_debugfs_false_color_fops);
> > >  }
> > >
> > >  void intel_fbc_crtc_debugfs_add(struct intel_crtc *crtc)
> > > --
> > > 2.34.1
> > >
> > >
> > >
> 
> 

Re: [PATCH] drm/i915/fbc: Avoid full proxy f_ops for FBC debug attributes

[Deepak R Varma]

On Wed, Dec 28, 2022 at 06:18:12AM -0500, Rodrigo Vivi wrote:
> On Tue, Dec 27, 2022 at 11:36:13PM +0530, Deepak R Varma wrote:
> > On Tue, Dec 27, 2022 at 12:13:56PM -0500, Rodrigo Vivi wrote:
> > > On Tue, Dec 27, 2022 at 01:30:53PM +0530, Deepak R Varma wrote:
> > > > Using DEFINE_SIMPLE_ATTRIBUTE macro with the debugfs_create_file()
> > > > function adds the overhead of introducing a proxy file operation
> > > > functions to wrap the original read/write inside file removal protection
> > > > functions. This adds significant overhead in terms of introducing and
> > > > managing the proxy factory file operations structure and function
> > > > wrapping at runtime.
> > > > As a replacement, a combination of DEFINE_DEBUGFS_ATTRIBUTE macro paired
> > > > with debugfs_create_file_unsafe() is suggested to be used instead.  The
> > > > DEFINE_DEBUGFS_ATTRIBUTE utilises debugfs_file_get() and
> > > > debugfs_file_put() wrappers to protect the original read and write
> > > > function calls for the debug attributes. There is no need for any
> > > > runtime proxy file operations to be managed by the debugfs core.
> > > >
> > > > This Change is reported by the debugfs_simple_attr.cocci Coccinelle
> > > > semantic patch.
> > >
> > > I just checked here with
> > > $ make coccicheck M=drivers/gpu/drm/i915/ MODE=context COCCI=./scripts/coccinelle/api/debugfs/debugfs_simple_attr.cocci
> >
> > Hello Rodrigo,
> > Thank you so much for your review and feedback on the patch proposal.
> >
> > >
> > > The part reported by the this script is the s/SIMPLE/DEBUGFS
> > > but the change to the unsafe option is not.
> >
> > If you look at the original commit of this coccinelle file, it calls out the
> > need for pairing debugfs_create_file_unsafe() as well. Please review this
> >
> > commitID: 5103068eaca2: ("debugfs, coccinelle: check for obsolete DEFINE_SIMPLE_ATTRIBUTE() usage")
>
> +Nicolai and Julia.
>
> It looks like coccinelle got right the
> - DEFINE_SIMPLE_ATTRIBUTE(dsa_fops, dsa_get, dsa_set, dsa_fmt);
> + DEFINE_DEBUGFS_ATTRIBUTE(dsa_fops, dsa_get, dsa_set, dsa_fmt);
>
> but it failed badly on
> - debugfs_create_file(name, mode, parent, data, &dsa_fops)
> + debugfs_create_file_unsafe(name, mode, parent, data, &dsa_fops)
>
> >
> > Based on my review of the code, the functions debugfs_create_file() and
> > debugfs_create_file_unsafe(), both internally call __debugfs_create_file().
> > However, they pass debugfs_full_proxy_file_operations and
> > debugfs_open_proxy_file_operations respectively to it. The former represents the
> > full proxy factory, where as the later one is lightweight open proxy
> > implementation of the file operations structure.
> >
> > >
> > > This commit message is not explaining why the unsafe is the suggested
> > > or who suggested it.
> >
> > If you find the response above accurate, I will include these details about
> > the _unsafe() function in my commit message in v2.
> >
> > >
> > > If you remove the unsafe part feel free to resend adding:
> >
> > Please confirm you still believe switching to _unsafe() is not necessary.
>
> Based on the coccinelle commit it looks like you are right, but cocinelle
> just failed to detect the case. Let's see what Nicolai and Julia respond
> before we move with any patch here.

Hello Nicolai and Julia,
Can you please review this proposed patch and the feedback comments from Rodrigo
please?

Thank you,
./drv

>
> >
> > >
> > > Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
> > > (to both patches, this and the drrs one.
> > >
> > > Also, it looks like you could contribute with other 2 patches:
> > > drivers/gpu/drm/i915/pxp/intel_pxp_debugfs.c:64:0-23: WARNING: pxp_terminate_fops should be defined with DEFINE_DEBUGFS_ATTRIBUTE
> > > drivers/gpu/drm/i915/gvt/debugfs.c:150:0-23: WARNING: vgpu_scan_nonprivbb_fops should be defined with DEFINE_DEBUGFS_ATTRIBUTE
> >
> > Yes, these are on my list. Was waiting for a feedback on the first submission
> > before I send more similar patches.
> >
> > Appreciate your time and the feedback.
> >
> >
> > Regards,
> > ./drv
> >
> > >
> > > >
> > > > Signed-off-by: Deepak R Varma <drv@mailo.com>
> > > > ---
> > > >  drivers/gpu/drm/i915/display/intel_fbc.c | 12 ++++++------
> > > >  1 file changed, 6 insertions(+), 6 deletions(-)
> > > >
> > > > diff --git a/drivers/gpu/drm/i915/display/intel_fbc.c b/drivers/gpu/drm/i915/display/intel_fbc.c
> > > > index b5ee5ea0d010..4b481e2f908b 100644
> > > > --- a/drivers/gpu/drm/i915/display/intel_fbc.c
> > > > +++ b/drivers/gpu/drm/i915/display/intel_fbc.c
> > > > @@ -1809,10 +1809,10 @@ static int intel_fbc_debugfs_false_color_set(void *data, u64 val)
> > > >  	return 0;
> > > >  }
> > > >
> > > > -DEFINE_SIMPLE_ATTRIBUTE(intel_fbc_debugfs_false_color_fops,
> > > > -			intel_fbc_debugfs_false_color_get,
> > > > -			intel_fbc_debugfs_false_color_set,
> > > > -			"%llu\n");
> > > > +DEFINE_DEBUGFS_ATTRIBUTE(intel_fbc_debugfs_false_color_fops,
> > > > +			 intel_fbc_debugfs_false_color_get,
> > > > +			 intel_fbc_debugfs_false_color_set,
> > > > +			 "%llu\n");
> > > >
> > > >  static void intel_fbc_debugfs_add(struct intel_fbc *fbc,
> > > >  				  struct dentry *parent)
> > > > @@ -1821,8 +1821,8 @@ static void intel_fbc_debugfs_add(struct intel_fbc *fbc,
> > > >  			    fbc, &intel_fbc_debugfs_status_fops);
> > > >
> > > >  	if (fbc->funcs->set_false_color)
> > > > -		debugfs_create_file("i915_fbc_false_color", 0644, parent,
> > > > -				    fbc, &intel_fbc_debugfs_false_color_fops);
> > > > +		debugfs_create_file_unsafe("i915_fbc_false_color", 0644, parent,
> > > > +					   fbc, &intel_fbc_debugfs_false_color_fops);
> > > >  }
> > > >
> > > >  void intel_fbc_crtc_debugfs_add(struct intel_crtc *crtc)
> > > > --
> > > > 2.34.1
> > > >
> > > >
> > > >
> >
> >
>

Re: [PATCH] drm/i915/fbc: Avoid full proxy f_ops for FBC debug attributes

[Julia Lawall]

On Tue, 3 Jan 2023, Deepak R Varma wrote:

> On Wed, Dec 28, 2022 at 06:18:12AM -0500, Rodrigo Vivi wrote:
> > On Tue, Dec 27, 2022 at 11:36:13PM +0530, Deepak R Varma wrote:
> > > On Tue, Dec 27, 2022 at 12:13:56PM -0500, Rodrigo Vivi wrote:
> > > > On Tue, Dec 27, 2022 at 01:30:53PM +0530, Deepak R Varma wrote:
> > > > > Using DEFINE_SIMPLE_ATTRIBUTE macro with the debugfs_create_file()
> > > > > function adds the overhead of introducing a proxy file operation
> > > > > functions to wrap the original read/write inside file removal protection
> > > > > functions. This adds significant overhead in terms of introducing and
> > > > > managing the proxy factory file operations structure and function
> > > > > wrapping at runtime.
> > > > > As a replacement, a combination of DEFINE_DEBUGFS_ATTRIBUTE macro paired
> > > > > with debugfs_create_file_unsafe() is suggested to be used instead.  The
> > > > > DEFINE_DEBUGFS_ATTRIBUTE utilises debugfs_file_get() and
> > > > > debugfs_file_put() wrappers to protect the original read and write
> > > > > function calls for the debug attributes. There is no need for any
> > > > > runtime proxy file operations to be managed by the debugfs core.
> > > > >
> > > > > This Change is reported by the debugfs_simple_attr.cocci Coccinelle
> > > > > semantic patch.
> > > >
> > > > I just checked here with
> > > > $ make coccicheck M=drivers/gpu/drm/i915/ MODE=context COCCI=./scripts/coccinelle/api/debugfs/debugfs_simple_attr.cocci
> > >
> > > Hello Rodrigo,
> > > Thank you so much for your review and feedback on the patch proposal.
> > >
> > > >
> > > > The part reported by the this script is the s/SIMPLE/DEBUGFS
> > > > but the change to the unsafe option is not.
> > >
> > > If you look at the original commit of this coccinelle file, it calls out the
> > > need for pairing debugfs_create_file_unsafe() as well. Please review this
> > >
> > > commitID: 5103068eaca2: ("debugfs, coccinelle: check for obsolete DEFINE_SIMPLE_ATTRIBUTE() usage")
> >
> > +Nicolai and Julia.
> >
> > It looks like coccinelle got right the
> > - DEFINE_SIMPLE_ATTRIBUTE(dsa_fops, dsa_get, dsa_set, dsa_fmt);
> > + DEFINE_DEBUGFS_ATTRIBUTE(dsa_fops, dsa_get, dsa_set, dsa_fmt);
> >
> > but it failed badly on
> > - debugfs_create_file(name, mode, parent, data, &dsa_fops)
> > + debugfs_create_file_unsafe(name, mode, parent, data, &dsa_fops)
> >
> > >
> > > Based on my review of the code, the functions debugfs_create_file() and
> > > debugfs_create_file_unsafe(), both internally call __debugfs_create_file().
> > > However, they pass debugfs_full_proxy_file_operations and
> > > debugfs_open_proxy_file_operations respectively to it. The former represents the
> > > full proxy factory, where as the later one is lightweight open proxy
> > > implementation of the file operations structure.
> > >
> > > >
> > > > This commit message is not explaining why the unsafe is the suggested
> > > > or who suggested it.
> > >
> > > If you find the response above accurate, I will include these details about
> > > the _unsafe() function in my commit message in v2.
> > >
> > > >
> > > > If you remove the unsafe part feel free to resend adding:
> > >
> > > Please confirm you still believe switching to _unsafe() is not necessary.
> >
> > Based on the coccinelle commit it looks like you are right, but cocinelle
> > just failed to detect the case. Let's see what Nicolai and Julia respond
> > before we move with any patch here.
>
> Hello Nicolai and Julia,
> Can you please review this proposed patch and the feedback comments from Rodrigo
> please?

I'm not an expert on this issue.  If the semantic patch needs to change in
some way, I would be happy to take any improvements.

julia


>
> Thank you,
> ./drv
>
> >
> > >
> > > >
> > > > Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
> > > > (to both patches, this and the drrs one.
> > > >
> > > > Also, it looks like you could contribute with other 2 patches:
> > > > drivers/gpu/drm/i915/pxp/intel_pxp_debugfs.c:64:0-23: WARNING: pxp_terminate_fops should be defined with DEFINE_DEBUGFS_ATTRIBUTE
> > > > drivers/gpu/drm/i915/gvt/debugfs.c:150:0-23: WARNING: vgpu_scan_nonprivbb_fops should be defined with DEFINE_DEBUGFS_ATTRIBUTE
> > >
> > > Yes, these are on my list. Was waiting for a feedback on the first submission
> > > before I send more similar patches.
> > >
> > > Appreciate your time and the feedback.
> > >
> > >
> > > Regards,
> > > ./drv
> > >
> > > >
> > > > >
> > > > > Signed-off-by: Deepak R Varma <drv@mailo.com>
> > > > > ---
> > > > >  drivers/gpu/drm/i915/display/intel_fbc.c | 12 ++++++------
> > > > >  1 file changed, 6 insertions(+), 6 deletions(-)
> > > > >
> > > > > diff --git a/drivers/gpu/drm/i915/display/intel_fbc.c b/drivers/gpu/drm/i915/display/intel_fbc.c
> > > > > index b5ee5ea0d010..4b481e2f908b 100644
> > > > > --- a/drivers/gpu/drm/i915/display/intel_fbc.c
> > > > > +++ b/drivers/gpu/drm/i915/display/intel_fbc.c
> > > > > @@ -1809,10 +1809,10 @@ static int intel_fbc_debugfs_false_color_set(void *data, u64 val)
> > > > >  	return 0;
> > > > >  }
> > > > >
> > > > > -DEFINE_SIMPLE_ATTRIBUTE(intel_fbc_debugfs_false_color_fops,
> > > > > -			intel_fbc_debugfs_false_color_get,
> > > > > -			intel_fbc_debugfs_false_color_set,
> > > > > -			"%llu\n");
> > > > > +DEFINE_DEBUGFS_ATTRIBUTE(intel_fbc_debugfs_false_color_fops,
> > > > > +			 intel_fbc_debugfs_false_color_get,
> > > > > +			 intel_fbc_debugfs_false_color_set,
> > > > > +			 "%llu\n");
> > > > >
> > > > >  static void intel_fbc_debugfs_add(struct intel_fbc *fbc,
> > > > >  				  struct dentry *parent)
> > > > > @@ -1821,8 +1821,8 @@ static void intel_fbc_debugfs_add(struct intel_fbc *fbc,
> > > > >  			    fbc, &intel_fbc_debugfs_status_fops);
> > > > >
> > > > >  	if (fbc->funcs->set_false_color)
> > > > > -		debugfs_create_file("i915_fbc_false_color", 0644, parent,
> > > > > -				    fbc, &intel_fbc_debugfs_false_color_fops);
> > > > > +		debugfs_create_file_unsafe("i915_fbc_false_color", 0644, parent,
> > > > > +					   fbc, &intel_fbc_debugfs_false_color_fops);
> > > > >  }
> > > > >
> > > > >  void intel_fbc_crtc_debugfs_add(struct intel_crtc *crtc)
> > > > > --
> > > > > 2.34.1
> > > > >
> > > > >
> > > > >
> > >
> > >
> >
>
>
>

Re: [PATCH] drm/i915/fbc: Avoid full proxy f_ops for FBC debug attributes

[Rodrigo Vivi]

On Wed, Jan 04, 2023 at 06:51:37PM +0100, Julia Lawall wrote:
> 
> 
> On Tue, 3 Jan 2023, Deepak R Varma wrote:
> 
> > On Wed, Dec 28, 2022 at 06:18:12AM -0500, Rodrigo Vivi wrote:
> > > On Tue, Dec 27, 2022 at 11:36:13PM +0530, Deepak R Varma wrote:
> > > > On Tue, Dec 27, 2022 at 12:13:56PM -0500, Rodrigo Vivi wrote:
> > > > > On Tue, Dec 27, 2022 at 01:30:53PM +0530, Deepak R Varma wrote:
> > > > > > Using DEFINE_SIMPLE_ATTRIBUTE macro with the debugfs_create_file()
> > > > > > function adds the overhead of introducing a proxy file operation
> > > > > > functions to wrap the original read/write inside file removal protection
> > > > > > functions. This adds significant overhead in terms of introducing and
> > > > > > managing the proxy factory file operations structure and function
> > > > > > wrapping at runtime.
> > > > > > As a replacement, a combination of DEFINE_DEBUGFS_ATTRIBUTE macro paired
> > > > > > with debugfs_create_file_unsafe() is suggested to be used instead.  The
> > > > > > DEFINE_DEBUGFS_ATTRIBUTE utilises debugfs_file_get() and
> > > > > > debugfs_file_put() wrappers to protect the original read and write
> > > > > > function calls for the debug attributes. There is no need for any
> > > > > > runtime proxy file operations to be managed by the debugfs core.
> > > > > >
> > > > > > This Change is reported by the debugfs_simple_attr.cocci Coccinelle
> > > > > > semantic patch.
> > > > >
> > > > > I just checked here with
> > > > > $ make coccicheck M=drivers/gpu/drm/i915/ MODE=context COCCI=./scripts/coccinelle/api/debugfs/debugfs_simple_attr.cocci
> > > >
> > > > Hello Rodrigo,
> > > > Thank you so much for your review and feedback on the patch proposal.
> > > >
> > > > >
> > > > > The part reported by the this script is the s/SIMPLE/DEBUGFS
> > > > > but the change to the unsafe option is not.
> > > >
> > > > If you look at the original commit of this coccinelle file, it calls out the
> > > > need for pairing debugfs_create_file_unsafe() as well. Please review this
> > > >
> > > > commitID: 5103068eaca2: ("debugfs, coccinelle: check for obsolete DEFINE_SIMPLE_ATTRIBUTE() usage")
> > >
> > > +Nicolai and Julia.
> > >
> > > It looks like coccinelle got right the
> > > - DEFINE_SIMPLE_ATTRIBUTE(dsa_fops, dsa_get, dsa_set, dsa_fmt);
> > > + DEFINE_DEBUGFS_ATTRIBUTE(dsa_fops, dsa_get, dsa_set, dsa_fmt);
> > >
> > > but it failed badly on
> > > - debugfs_create_file(name, mode, parent, data, &dsa_fops)
> > > + debugfs_create_file_unsafe(name, mode, parent, data, &dsa_fops)
> > >
> > > >
> > > > Based on my review of the code, the functions debugfs_create_file() and
> > > > debugfs_create_file_unsafe(), both internally call __debugfs_create_file().
> > > > However, they pass debugfs_full_proxy_file_operations and
> > > > debugfs_open_proxy_file_operations respectively to it. The former represents the
> > > > full proxy factory, where as the later one is lightweight open proxy
> > > > implementation of the file operations structure.
> > > >
> > > > >
> > > > > This commit message is not explaining why the unsafe is the suggested
> > > > > or who suggested it.
> > > >
> > > > If you find the response above accurate, I will include these details about
> > > > the _unsafe() function in my commit message in v2.
> > > >
> > > > >
> > > > > If you remove the unsafe part feel free to resend adding:
> > > >
> > > > Please confirm you still believe switching to _unsafe() is not necessary.
> > >
> > > Based on the coccinelle commit it looks like you are right, but cocinelle
> > > just failed to detect the case. Let's see what Nicolai and Julia respond
> > > before we move with any patch here.
> >
> > Hello Nicolai and Julia,
> > Can you please review this proposed patch and the feedback comments from Rodrigo
> > please?
> 
> I'm not an expert on this issue.  If the semantic patch needs to change in
> some way, I would be happy to take any improvements.

Hi Julia, thanks for helping here.

So, my question is why this 

make coccicheck M=drivers/gpu/drm/i915/ MODE=context COCCI=./scripts/coccinelle/api/debugfs/debugfs_simple_attr.cocci 

didn't catch this chunck:

-		debugfs_create_file("i915_fbc_false_color", 0644, parent,
-				    fbc, &intel_fbc_debugfs_false_color_fops);
+		debugfs_create_file_unsafe("i915_fbc_false_color", 0644, parent,
+					   fbc, &intel_fbc_debugfs_false_color_fops);

When I run it it only catches and replaces this:

- DEFINE_SIMPLE_ATTRIBUTE(dsa_fops, dsa_get, dsa_set, dsa_fmt);
+ DEFINE_DEBUGFS_ATTRIBUTE(dsa_fops, dsa_get, dsa_set, dsa_fmt);

But looking to the .cocci script or at least to its description,
I believe it should catch both cases.

But if it is not a bug in the cocci script, then I'd like to hear
from Nicolai why. And have this documented in the script.

Thanks,
Rodrigo.

> 
> julia
> 
> 
> >
> > Thank you,
> > ./drv
> >
> > >
> > > >
> > > > >
> > > > > Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
> > > > > (to both patches, this and the drrs one.
> > > > >
> > > > > Also, it looks like you could contribute with other 2 patches:
> > > > > drivers/gpu/drm/i915/pxp/intel_pxp_debugfs.c:64:0-23: WARNING: pxp_terminate_fops should be defined with DEFINE_DEBUGFS_ATTRIBUTE
> > > > > drivers/gpu/drm/i915/gvt/debugfs.c:150:0-23: WARNING: vgpu_scan_nonprivbb_fops should be defined with DEFINE_DEBUGFS_ATTRIBUTE
> > > >
> > > > Yes, these are on my list. Was waiting for a feedback on the first submission
> > > > before I send more similar patches.
> > > >
> > > > Appreciate your time and the feedback.
> > > >
> > > >
> > > > Regards,
> > > > ./drv
> > > >
> > > > >
> > > > > >
> > > > > > Signed-off-by: Deepak R Varma <drv@mailo.com>
> > > > > > ---
> > > > > >  drivers/gpu/drm/i915/display/intel_fbc.c | 12 ++++++------
> > > > > >  1 file changed, 6 insertions(+), 6 deletions(-)
> > > > > >
> > > > > > diff --git a/drivers/gpu/drm/i915/display/intel_fbc.c b/drivers/gpu/drm/i915/display/intel_fbc.c
> > > > > > index b5ee5ea0d010..4b481e2f908b 100644
> > > > > > --- a/drivers/gpu/drm/i915/display/intel_fbc.c
> > > > > > +++ b/drivers/gpu/drm/i915/display/intel_fbc.c
> > > > > > @@ -1809,10 +1809,10 @@ static int intel_fbc_debugfs_false_color_set(void *data, u64 val)
> > > > > >  	return 0;
> > > > > >  }
> > > > > >
> > > > > > -DEFINE_SIMPLE_ATTRIBUTE(intel_fbc_debugfs_false_color_fops,
> > > > > > -			intel_fbc_debugfs_false_color_get,
> > > > > > -			intel_fbc_debugfs_false_color_set,
> > > > > > -			"%llu\n");
> > > > > > +DEFINE_DEBUGFS_ATTRIBUTE(intel_fbc_debugfs_false_color_fops,
> > > > > > +			 intel_fbc_debugfs_false_color_get,
> > > > > > +			 intel_fbc_debugfs_false_color_set,
> > > > > > +			 "%llu\n");
> > > > > >
> > > > > >  static void intel_fbc_debugfs_add(struct intel_fbc *fbc,
> > > > > >  				  struct dentry *parent)
> > > > > > @@ -1821,8 +1821,8 @@ static void intel_fbc_debugfs_add(struct intel_fbc *fbc,
> > > > > >  			    fbc, &intel_fbc_debugfs_status_fops);
> > > > > >
> > > > > >  	if (fbc->funcs->set_false_color)
> > > > > > -		debugfs_create_file("i915_fbc_false_color", 0644, parent,
> > > > > > -				    fbc, &intel_fbc_debugfs_false_color_fops);
> > > > > > +		debugfs_create_file_unsafe("i915_fbc_false_color", 0644, parent,
> > > > > > +					   fbc, &intel_fbc_debugfs_false_color_fops);
> > > > > >  }
> > > > > >
> > > > > >  void intel_fbc_crtc_debugfs_add(struct intel_crtc *crtc)
> > > > > > --
> > > > > > 2.34.1
> > > > > >
> > > > > >
> > > > > >
> > > >
> > > >
> > >
> >
> >
> >

Re: [PATCH] drm/i915/fbc: Avoid full proxy f_ops for FBC debug attributes

[Julia Lawall]

> Hi Julia, thanks for helping here.
>
> So, my question is why this
>
> make coccicheck M=drivers/gpu/drm/i915/ MODE=context COCCI=./scripts/coccinelle/api/debugfs/debugfs_simple_attr.cocci
>
> didn't catch this chunck:
>
> -		debugfs_create_file("i915_fbc_false_color", 0644, parent,
> -				    fbc, &intel_fbc_debugfs_false_color_fops);
> +		debugfs_create_file_unsafe("i915_fbc_false_color", 0644, parent,
> +					   fbc, &intel_fbc_debugfs_false_color_fops);
>
> When I run it it only catches and replaces this:
>
> - DEFINE_SIMPLE_ATTRIBUTE(dsa_fops, dsa_get, dsa_set, dsa_fmt);
> + DEFINE_DEBUGFS_ATTRIBUTE(dsa_fops, dsa_get, dsa_set, dsa_fmt);

There is something strange in your question.  You have MODE=context but
you show the output for MODE=patch.  The rule dcf matches a call to
debugfs_create_file, and the context rule matching DEFINE_SIMPLE_ATTRIBUTE
is only activated if dcf succeeds.  So when the context rule gives a
report, there is always a corresponding call to debugfs_create_file in the
same file, it is just not highlighted.  So the request is that it should
be highlighted as well?

julia

>
> But looking to the .cocci script or at least to its description,
> I believe it should catch both cases.
>
> But if it is not a bug in the cocci script, then I'd like to hear
> from Nicolai why. And have this documented in the script.
>
> Thanks,
> Rodrigo.
>
> >
> > julia
> >
> >
> > >
> > > Thank you,
> > > ./drv
> > >
> > > >
> > > > >
> > > > > >
> > > > > > Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
> > > > > > (to both patches, this and the drrs one.
> > > > > >
> > > > > > Also, it looks like you could contribute with other 2 patches:
> > > > > > drivers/gpu/drm/i915/pxp/intel_pxp_debugfs.c:64:0-23: WARNING: pxp_terminate_fops should be defined with DEFINE_DEBUGFS_ATTRIBUTE
> > > > > > drivers/gpu/drm/i915/gvt/debugfs.c:150:0-23: WARNING: vgpu_scan_nonprivbb_fops should be defined with DEFINE_DEBUGFS_ATTRIBUTE
> > > > >
> > > > > Yes, these are on my list. Was waiting for a feedback on the first submission
> > > > > before I send more similar patches.
> > > > >
> > > > > Appreciate your time and the feedback.
> > > > >
> > > > >
> > > > > Regards,
> > > > > ./drv
> > > > >
> > > > > >
> > > > > > >
> > > > > > > Signed-off-by: Deepak R Varma <drv@mailo.com>
> > > > > > > ---
> > > > > > >  drivers/gpu/drm/i915/display/intel_fbc.c | 12 ++++++------
> > > > > > >  1 file changed, 6 insertions(+), 6 deletions(-)
> > > > > > >
> > > > > > > diff --git a/drivers/gpu/drm/i915/display/intel_fbc.c b/drivers/gpu/drm/i915/display/intel_fbc.c
> > > > > > > index b5ee5ea0d010..4b481e2f908b 100644
> > > > > > > --- a/drivers/gpu/drm/i915/display/intel_fbc.c
> > > > > > > +++ b/drivers/gpu/drm/i915/display/intel_fbc.c
> > > > > > > @@ -1809,10 +1809,10 @@ static int intel_fbc_debugfs_false_color_set(void *data, u64 val)
> > > > > > >  	return 0;
> > > > > > >  }
> > > > > > >
> > > > > > > -DEFINE_SIMPLE_ATTRIBUTE(intel_fbc_debugfs_false_color_fops,
> > > > > > > -			intel_fbc_debugfs_false_color_get,
> > > > > > > -			intel_fbc_debugfs_false_color_set,
> > > > > > > -			"%llu\n");
> > > > > > > +DEFINE_DEBUGFS_ATTRIBUTE(intel_fbc_debugfs_false_color_fops,
> > > > > > > +			 intel_fbc_debugfs_false_color_get,
> > > > > > > +			 intel_fbc_debugfs_false_color_set,
> > > > > > > +			 "%llu\n");
> > > > > > >
> > > > > > >  static void intel_fbc_debugfs_add(struct intel_fbc *fbc,
> > > > > > >  				  struct dentry *parent)
> > > > > > > @@ -1821,8 +1821,8 @@ static void intel_fbc_debugfs_add(struct intel_fbc *fbc,
> > > > > > >  			    fbc, &intel_fbc_debugfs_status_fops);
> > > > > > >
> > > > > > >  	if (fbc->funcs->set_false_color)
> > > > > > > -		debugfs_create_file("i915_fbc_false_color", 0644, parent,
> > > > > > > -				    fbc, &intel_fbc_debugfs_false_color_fops);
> > > > > > > +		debugfs_create_file_unsafe("i915_fbc_false_color", 0644, parent,
> > > > > > > +					   fbc, &intel_fbc_debugfs_false_color_fops);
> > > > > > >  }
> > > > > > >
> > > > > > >  void intel_fbc_crtc_debugfs_add(struct intel_crtc *crtc)
> > > > > > > --
> > > > > > > 2.34.1
> > > > > > >
> > > > > > >
> > > > > > >
> > > > >
> > > > >
> > > >
> > >
> > >
> > >
>

Re: [PATCH] drm/i915/fbc: Avoid full proxy f_ops for FBC debug attributes

[Deepak R Varma]

On Thu, Jan 05, 2023 at 09:13:35AM +0100, Julia Lawall wrote:
> > Hi Julia, thanks for helping here.
> >
> > So, my question is why this
> >
> > make coccicheck M=drivers/gpu/drm/i915/ MODE=context COCCI=./scripts/coccinelle/api/debugfs/debugfs_simple_attr.cocci
> >
> > didn't catch this chunck:
> >
> > -		debugfs_create_file("i915_fbc_false_color", 0644, parent,
> > -				    fbc, &intel_fbc_debugfs_false_color_fops);
> > +		debugfs_create_file_unsafe("i915_fbc_false_color", 0644, parent,
> > +					   fbc, &intel_fbc_debugfs_false_color_fops);
> >
> > When I run it it only catches and replaces this:
> >
> > - DEFINE_SIMPLE_ATTRIBUTE(dsa_fops, dsa_get, dsa_set, dsa_fmt);
> > + DEFINE_DEBUGFS_ATTRIBUTE(dsa_fops, dsa_get, dsa_set, dsa_fmt);
>
> There is something strange in your question.  You have MODE=context but
> you show the output for MODE=patch.  The rule dcf matches a call to
> debugfs_create_file, and the context rule matching DEFINE_SIMPLE_ATTRIBUTE
> is only activated if dcf succeeds.  So when the context rule gives a
> report, there is always a corresponding call to debugfs_create_file in the
> same file, it is just not highlighted.  So the request is that it should
> be highlighted as well?

Hello Rodrigo,
Not trying to speak for you, but I think Julia's comment appears to be the
correct interpretation of your observation. Would you mind confirming/clarifying
and suggest next steps for this proposal?

Thank you,
./drv

>
> julia
>

Re: [PATCH] drm/i915/fbc: Avoid full proxy f_ops for FBC debug attributes

[Rodrigo Vivi]

On Sun, Jan 08, 2023 at 01:33:41AM +0530, Deepak R Varma wrote:
> On Thu, Jan 05, 2023 at 09:13:35AM +0100, Julia Lawall wrote:
> > > Hi Julia, thanks for helping here.
> > >
> > > So, my question is why this
> > >
> > > make coccicheck M=drivers/gpu/drm/i915/ MODE=context COCCI=./scripts/coccinelle/api/debugfs/debugfs_simple_attr.cocci
> > >
> > > didn't catch this chunck:
> > >
> > > -		debugfs_create_file("i915_fbc_false_color", 0644, parent,
> > > -				    fbc, &intel_fbc_debugfs_false_color_fops);
> > > +		debugfs_create_file_unsafe("i915_fbc_false_color", 0644, parent,
> > > +					   fbc, &intel_fbc_debugfs_false_color_fops);
> > >
> > > When I run it it only catches and replaces this:
> > >
> > > - DEFINE_SIMPLE_ATTRIBUTE(dsa_fops, dsa_get, dsa_set, dsa_fmt);
> > > + DEFINE_DEBUGFS_ATTRIBUTE(dsa_fops, dsa_get, dsa_set, dsa_fmt);
> >
> > There is something strange in your question.  You have MODE=context but
> > you show the output for MODE=patch.  The rule dcf matches a call to
> > debugfs_create_file, and the context rule matching DEFINE_SIMPLE_ATTRIBUTE
> > is only activated if dcf succeeds.  So when the context rule gives a
> > report, there is always a corresponding call to debugfs_create_file in the
> > same file, it is just not highlighted.  So the request is that it should
> > be highlighted as well?
> 
> Hello Rodrigo,
> Not trying to speak for you, but I think Julia's comment appears to be the
> correct interpretation of your observation. Would you mind confirming/clarifying
> and suggest next steps for this proposal?

doh! newby coccinelle user detected! My bad, sorry!

make coccicheck M=drivers/gpu/drm/i915/ MODE=patch COCCI=./scripts/coccinelle/api/debugfs/debugfs_simple_attr.cocci

do shows everything.

So, could you please mention this line in the commit message so we don't forget that?

Also could you please provide patches for the other cases?
1 patch for each file is desirable in this case since it touches different areas.

> 
> Thank you,
> ./drv
> 
> >
> > julia
> >
> 
> 

Re: [PATCH] drm/i915/fbc: Avoid full proxy f_ops for FBC debug attributes

[Deepak R Varma]

On Mon, Jan 09, 2023 at 02:06:13PM -0500, Rodrigo Vivi wrote:
> On Sun, Jan 08, 2023 at 01:33:41AM +0530, Deepak R Varma wrote:
> > On Thu, Jan 05, 2023 at 09:13:35AM +0100, Julia Lawall wrote:
> > > > Hi Julia, thanks for helping here.
> > > >
> > > > So, my question is why this
> > > >
> > > > make coccicheck M=drivers/gpu/drm/i915/ MODE=context COCCI=./scripts/coccinelle/api/debugfs/debugfs_simple_attr.cocci
> > > >
> > > > didn't catch this chunck:
> > > >
> > > > -		debugfs_create_file("i915_fbc_false_color", 0644, parent,
> > > > -				    fbc, &intel_fbc_debugfs_false_color_fops);
> > > > +		debugfs_create_file_unsafe("i915_fbc_false_color", 0644, parent,
> > > > +					   fbc, &intel_fbc_debugfs_false_color_fops);
> > > >
> > > > When I run it it only catches and replaces this:
> > > >
> > > > - DEFINE_SIMPLE_ATTRIBUTE(dsa_fops, dsa_get, dsa_set, dsa_fmt);
> > > > + DEFINE_DEBUGFS_ATTRIBUTE(dsa_fops, dsa_get, dsa_set, dsa_fmt);
> > >
> > > There is something strange in your question.  You have MODE=context but
> > > you show the output for MODE=patch.  The rule dcf matches a call to
> > > debugfs_create_file, and the context rule matching DEFINE_SIMPLE_ATTRIBUTE
> > > is only activated if dcf succeeds.  So when the context rule gives a
> > > report, there is always a corresponding call to debugfs_create_file in the
> > > same file, it is just not highlighted.  So the request is that it should
> > > be highlighted as well?
> > 
> > Hello Rodrigo,
> > Not trying to speak for you, but I think Julia's comment appears to be the
> > correct interpretation of your observation. Would you mind confirming/clarifying
> > and suggest next steps for this proposal?
> 
> doh! newby coccinelle user detected! My bad, sorry!
> 
> make coccicheck M=drivers/gpu/drm/i915/ MODE=patch COCCI=./scripts/coccinelle/api/debugfs/debugfs_simple_attr.cocci
> 
> do shows everything.
> 
> So, could you please mention this line in the commit message so we don't forget that?
Sure, I will do that.

> 
> Also could you please provide patches for the other cases?
> 1 patch for each file is desirable in this case since it touches different areas.
Sounds good. I will separate patches one per file and send in a series as
appropriate.

Thank you,
./drv

> 
> > 
> > Thank you,
> > ./drv
> > 
> > >
> > > julia
> > >
> > 
> >