[RESEND PATCH] staging: rtl8188eu: Fix else after return WARNING (checkpatch)

[RESEND PATCH] staging: rtl8188eu: Fix else after return WARNING (checkpatch)

[Sohom Datta]

From 4c8c8f3ff7f4d711daea4ac3bb987fcecc7ef1ed Mon Sep 17 00:00:00 2001
From: Sohom <sohom.datta@learner.manipal.edu>
Date: Sat, 12 Sep 2020 18:04:56 +0530
Subject: [RESEND PATCH] staging: rtl8188eu: Fix else after return WARNING
 (checkpatch)

Fixed:
WARNING: else is not generally useful after a break or return
1636: FILE: ./rtw_recv.c:1636:
+           return false;
+       else

Separated the return statement into a separate block since
it doesn't seem to depend on the SN_LESS explicity being false.

Signed-off-by: Sohom <sohom.datta@learner.manipal.edu>
---
 drivers/staging/rtl8188eu/core/rtw_recv.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/staging/rtl8188eu/core/rtw_recv.c b/drivers/staging/rtl8188eu/core/rtw_recv.c
index 5fe7a0458dd2..5e81134ffb6d 100644
--- a/drivers/staging/rtl8188eu/core/rtw_recv.c
+++ b/drivers/staging/rtl8188eu/core/rtw_recv.c
@@ -1629,10 +1629,11 @@ static int enqueue_reorder_recvframe(struct recv_reorder_ctrl *preorder_ctrl,
 		hdr = list_entry(plist, struct recv_frame, list);
 		pnextattrib = &hdr->attrib;
 
+		if (SN_EQUAL(pnextattrib->seq_num, pattrib->seq_num))
+			return false;
+
 		if (SN_LESS(pnextattrib->seq_num, pattrib->seq_num))
 			plist = plist->next;
-		else if (SN_EQUAL(pnextattrib->seq_num, pattrib->seq_num))
-			return false;
 		else
 			break;
 	}
-- 
2.28.0

[RESEND PATCH] staging: rtl8188eu: Fix else after return WARNING (checkpatch)

[Sohom Datta]

From 4c8c8f3ff7f4d711daea4ac3bb987fcecc7ef1ed Mon Sep 17 00:00:00 2001
From: Sohom <sohom.datta@learner.manipal.edu>
Date: Sat, 12 Sep 2020 18:04:56 +0530
Subject: [RESEND PATCH] staging: rtl8188eu: Fix else after return WARNING
 (checkpatch)

Fixed:
WARNING: else is not generally useful after a break or return
1636: FILE: ./rtw_recv.c:1636:
+           return false;
+       else

Separated the return statement into a separate block since
it doesn't seem to depend on the SN_LESS explicity being false.

Signed-off-by: Sohom <sohom.datta@learner.manipal.edu>
---
 drivers/staging/rtl8188eu/core/rtw_recv.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/staging/rtl8188eu/core/rtw_recv.c b/drivers/staging/rtl8188eu/core/rtw_recv.c
index 5fe7a0458dd2..5e81134ffb6d 100644
--- a/drivers/staging/rtl8188eu/core/rtw_recv.c
+++ b/drivers/staging/rtl8188eu/core/rtw_recv.c
@@ -1629,10 +1629,11 @@ static int enqueue_reorder_recvframe(struct recv_reorder_ctrl *preorder_ctrl,
 		hdr = list_entry(plist, struct recv_frame, list);
 		pnextattrib = &hdr->attrib;
 
+		if (SN_EQUAL(pnextattrib->seq_num, pattrib->seq_num))
+			return false;
+
 		if (SN_LESS(pnextattrib->seq_num, pattrib->seq_num))
 			plist = plist->next;
-		else if (SN_EQUAL(pnextattrib->seq_num, pattrib->seq_num))
-			return false;
 		else
 			break;
 	}
-- 
2.28.0


_______________________________________________
devel mailing list
devel@linuxdriverproject.org
http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel

Re: [RESEND PATCH] staging: rtl8188eu: Fix else after return WARNING (checkpatch)

[Greg Kroah-Hartman]

On Sun, Sep 13, 2020 at 12:19:50PM +0530, Sohom Datta wrote:
> >From 4c8c8f3ff7f4d711daea4ac3bb987fcecc7ef1ed Mon Sep 17 00:00:00 2001
> From: Sohom <sohom.datta@learner.manipal.edu>
> Date: Sat, 12 Sep 2020 18:04:56 +0530
> Subject: [RESEND PATCH] staging: rtl8188eu: Fix else after return WARNING
>  (checkpatch)

Why is this in the body of your email?

Just use 'git send-email' to send the patch, no need to include it in
the body itself, right?

thanks,

greg k-h

Re: [RESEND PATCH] staging: rtl8188eu: Fix else after return WARNING (checkpatch)

[Greg Kroah-Hartman]

On Sun, Sep 13, 2020 at 12:19:50PM +0530, Sohom Datta wrote:
> >From 4c8c8f3ff7f4d711daea4ac3bb987fcecc7ef1ed Mon Sep 17 00:00:00 2001
> From: Sohom <sohom.datta@learner.manipal.edu>
> Date: Sat, 12 Sep 2020 18:04:56 +0530
> Subject: [RESEND PATCH] staging: rtl8188eu: Fix else after return WARNING
>  (checkpatch)

Why is this in the body of your email?

Just use 'git send-email' to send the patch, no need to include it in
the body itself, right?

thanks,

greg k-h
_______________________________________________
devel mailing list
devel@linuxdriverproject.org
http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel

Re: [RESEND PATCH] staging: rtl8188eu: Fix else after return WARNING (checkpatch)

[Dan Carpenter]

On Sun, Sep 13, 2020 at 12:19:50PM +0530, Sohom Datta wrote:
> >From 4c8c8f3ff7f4d711daea4ac3bb987fcecc7ef1ed Mon Sep 17 00:00:00 2001
> From: Sohom <sohom.datta@learner.manipal.edu>
> Date: Sat, 12 Sep 2020 18:04:56 +0530
> Subject: [RESEND PATCH] staging: rtl8188eu: Fix else after return WARNING
>  (checkpatch)
> 
> Fixed:
> WARNING: else is not generally useful after a break or return
> 1636: FILE: ./rtw_recv.c:1636:
> +           return false;
> +       else
> 
> Separated the return statement into a separate block since
> it doesn't seem to depend on the SN_LESS explicity being false.
> 
> Signed-off-by: Sohom <sohom.datta@learner.manipal.edu>
> ---
>  drivers/staging/rtl8188eu/core/rtw_recv.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/staging/rtl8188eu/core/rtw_recv.c b/drivers/staging/rtl8188eu/core/rtw_recv.c
> index 5fe7a0458dd2..5e81134ffb6d 100644
> --- a/drivers/staging/rtl8188eu/core/rtw_recv.c
> +++ b/drivers/staging/rtl8188eu/core/rtw_recv.c
> @@ -1629,10 +1629,11 @@ static int enqueue_reorder_recvframe(struct recv_reorder_ctrl *preorder_ctrl,
>  		hdr = list_entry(plist, struct recv_frame, list);
>  		pnextattrib = &hdr->attrib;
>  
> +		if (SN_EQUAL(pnextattrib->seq_num, pattrib->seq_num))
> +			return false;
> +
>  		if (SN_LESS(pnextattrib->seq_num, pattrib->seq_num))
>  			plist = plist->next;
> -		else if (SN_EQUAL(pnextattrib->seq_num, pattrib->seq_num))
> -			return false;
>  		else
>  			break;
>  	}

Checkpatch is just wrong here.  Ignore it when it's wrong.

regards,
dan carpenter

Re: [RESEND PATCH] staging: rtl8188eu: Fix else after return WARNING (checkpatch)

[Dan Carpenter]

On Sun, Sep 13, 2020 at 12:19:50PM +0530, Sohom Datta wrote:
> >From 4c8c8f3ff7f4d711daea4ac3bb987fcecc7ef1ed Mon Sep 17 00:00:00 2001
> From: Sohom <sohom.datta@learner.manipal.edu>
> Date: Sat, 12 Sep 2020 18:04:56 +0530
> Subject: [RESEND PATCH] staging: rtl8188eu: Fix else after return WARNING
>  (checkpatch)
> 
> Fixed:
> WARNING: else is not generally useful after a break or return
> 1636: FILE: ./rtw_recv.c:1636:
> +           return false;
> +       else
> 
> Separated the return statement into a separate block since
> it doesn't seem to depend on the SN_LESS explicity being false.
> 
> Signed-off-by: Sohom <sohom.datta@learner.manipal.edu>
> ---
>  drivers/staging/rtl8188eu/core/rtw_recv.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/staging/rtl8188eu/core/rtw_recv.c b/drivers/staging/rtl8188eu/core/rtw_recv.c
> index 5fe7a0458dd2..5e81134ffb6d 100644
> --- a/drivers/staging/rtl8188eu/core/rtw_recv.c
> +++ b/drivers/staging/rtl8188eu/core/rtw_recv.c
> @@ -1629,10 +1629,11 @@ static int enqueue_reorder_recvframe(struct recv_reorder_ctrl *preorder_ctrl,
>  		hdr = list_entry(plist, struct recv_frame, list);
>  		pnextattrib = &hdr->attrib;
>  
> +		if (SN_EQUAL(pnextattrib->seq_num, pattrib->seq_num))
> +			return false;
> +
>  		if (SN_LESS(pnextattrib->seq_num, pattrib->seq_num))
>  			plist = plist->next;
> -		else if (SN_EQUAL(pnextattrib->seq_num, pattrib->seq_num))
> -			return false;
>  		else
>  			break;
>  	}

Checkpatch is just wrong here.  Ignore it when it's wrong.

regards,
dan carpenter

_______________________________________________
devel mailing list
devel@linuxdriverproject.org
http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel

Re: [RESEND PATCH] staging: rtl8188eu: Fix else after return WARNING (checkpatch)

[Joe Perches]

On Mon, 2020-09-14 at 17:57 +0300, Dan Carpenter wrote:
> On Sun, Sep 13, 2020 at 12:19:50PM +0530, Sohom Datta wrote:
> > > From 4c8c8f3ff7f4d711daea4ac3bb987fcecc7ef1ed Mon Sep 17 00:00:00 2001
> > From: Sohom <sohom.datta@learner.manipal.edu>
> > Date: Sat, 12 Sep 2020 18:04:56 +0530
> > Subject: [RESEND PATCH] staging: rtl8188eu: Fix else after return WARNING
> >  (checkpatch)
> > 
> > Fixed:
> > WARNING: else is not generally useful after a break or return
> > 1636: FILE: ./rtw_recv.c:1636:
> > +           return false;
> > +       else
> > 
> > Separated the return statement into a separate block since
> > it doesn't seem to depend on the SN_LESS explicity being false.
> > 
> > Signed-off-by: Sohom <sohom.datta@learner.manipal.edu>
> > ---
> >  drivers/staging/rtl8188eu/core/rtw_recv.c | 5 +++--
> >  1 file changed, 3 insertions(+), 2 deletions(-)
> > 
> > diff --git a/drivers/staging/rtl8188eu/core/rtw_recv.c b/drivers/staging/rtl8188eu/core/rtw_recv.c
> > index 5fe7a0458dd2..5e81134ffb6d 100644
> > --- a/drivers/staging/rtl8188eu/core/rtw_recv.c
> > +++ b/drivers/staging/rtl8188eu/core/rtw_recv.c
> > @@ -1629,10 +1629,11 @@ static int enqueue_reorder_recvframe(struct recv_reorder_ctrl *preorder_ctrl,
> >  		hdr = list_entry(plist, struct recv_frame, list);
> >  		pnextattrib = &hdr->attrib;
> >  
> > +		if (SN_EQUAL(pnextattrib->seq_num, pattrib->seq_num))
> > +			return false;
> > +
> >  		if (SN_LESS(pnextattrib->seq_num, pattrib->seq_num))
> >  			plist = plist->next;
> > -		else if (SN_EQUAL(pnextattrib->seq_num, pattrib->seq_num))
> > -			return false;
> >  		else
> >  			break;
> >  	}
> 
> Checkpatch is just wrong here.  Ignore it when it's wrong.

It's not "wrong" here.  It's making a suggestion.

Perhaps read the SN_EQUAL and SN_LESS macros.

a and b are both u16's here.

drivers/staging/rtl8188eu/include/rtw_recv.h:#define SN_LESS(a, b)              (((a - b) & 0x800) != 0)
drivers/staging/rtl8188eu/include/rtw_recv.h:#define SN_EQUAL(a, b)     (a == b)

Reordering works, perhaps it's just a question of
whether it's the most likely result of the test.

This is in a while loop.

If the expected test is really the most likely that
SN_LESS is true, then perhaps this loop could be
something like:

		if (SN_LESS(pnextattrib->seq_num, pattrib->seq_num)) {
			plist = plist->next;
			continue;
		}
		if (SN_EQUAL(pnextattrib->seq_num, pattrib->seq_num))
			return false;
		break;
	}

The real question is whether or not that's more readable.

Re: [RESEND PATCH] staging: rtl8188eu: Fix else after return WARNING (checkpatch)

[Joe Perches]

On Mon, 2020-09-14 at 17:57 +0300, Dan Carpenter wrote:
> On Sun, Sep 13, 2020 at 12:19:50PM +0530, Sohom Datta wrote:
> > > From 4c8c8f3ff7f4d711daea4ac3bb987fcecc7ef1ed Mon Sep 17 00:00:00 2001
> > From: Sohom <sohom.datta@learner.manipal.edu>
> > Date: Sat, 12 Sep 2020 18:04:56 +0530
> > Subject: [RESEND PATCH] staging: rtl8188eu: Fix else after return WARNING
> >  (checkpatch)
> > 
> > Fixed:
> > WARNING: else is not generally useful after a break or return
> > 1636: FILE: ./rtw_recv.c:1636:
> > +           return false;
> > +       else
> > 
> > Separated the return statement into a separate block since
> > it doesn't seem to depend on the SN_LESS explicity being false.
> > 
> > Signed-off-by: Sohom <sohom.datta@learner.manipal.edu>
> > ---
> >  drivers/staging/rtl8188eu/core/rtw_recv.c | 5 +++--
> >  1 file changed, 3 insertions(+), 2 deletions(-)
> > 
> > diff --git a/drivers/staging/rtl8188eu/core/rtw_recv.c b/drivers/staging/rtl8188eu/core/rtw_recv.c
> > index 5fe7a0458dd2..5e81134ffb6d 100644
> > --- a/drivers/staging/rtl8188eu/core/rtw_recv.c
> > +++ b/drivers/staging/rtl8188eu/core/rtw_recv.c
> > @@ -1629,10 +1629,11 @@ static int enqueue_reorder_recvframe(struct recv_reorder_ctrl *preorder_ctrl,
> >  		hdr = list_entry(plist, struct recv_frame, list);
> >  		pnextattrib = &hdr->attrib;
> >  
> > +		if (SN_EQUAL(pnextattrib->seq_num, pattrib->seq_num))
> > +			return false;
> > +
> >  		if (SN_LESS(pnextattrib->seq_num, pattrib->seq_num))
> >  			plist = plist->next;
> > -		else if (SN_EQUAL(pnextattrib->seq_num, pattrib->seq_num))
> > -			return false;
> >  		else
> >  			break;
> >  	}
> 
> Checkpatch is just wrong here.  Ignore it when it's wrong.

It's not "wrong" here.  It's making a suggestion.

Perhaps read the SN_EQUAL and SN_LESS macros.

a and b are both u16's here.

drivers/staging/rtl8188eu/include/rtw_recv.h:#define SN_LESS(a, b)              (((a - b) & 0x800) != 0)
drivers/staging/rtl8188eu/include/rtw_recv.h:#define SN_EQUAL(a, b)     (a == b)

Reordering works, perhaps it's just a question of
whether it's the most likely result of the test.

This is in a while loop.

If the expected test is really the most likely that
SN_LESS is true, then perhaps this loop could be
something like:

		if (SN_LESS(pnextattrib->seq_num, pattrib->seq_num)) {
			plist = plist->next;
			continue;
		}
		if (SN_EQUAL(pnextattrib->seq_num, pattrib->seq_num))
			return false;
		break;
	}

The real question is whether or not that's more readable.


_______________________________________________
devel mailing list
devel@linuxdriverproject.org
http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel

Re: [RESEND PATCH] staging: rtl8188eu: Fix else after return WARNING (checkpatch)

[Dan Carpenter]

On Mon, Sep 14, 2020 at 09:42:49AM -0700, Joe Perches wrote:
> On Mon, 2020-09-14 at 17:57 +0300, Dan Carpenter wrote:
> > On Sun, Sep 13, 2020 at 12:19:50PM +0530, Sohom Datta wrote:
> > > > From 4c8c8f3ff7f4d711daea4ac3bb987fcecc7ef1ed Mon Sep 17 00:00:00 2001
> > > From: Sohom <sohom.datta@learner.manipal.edu>
> > > Date: Sat, 12 Sep 2020 18:04:56 +0530
> > > Subject: [RESEND PATCH] staging: rtl8188eu: Fix else after return WARNING
> > >  (checkpatch)
> > > 
> > > Fixed:
> > > WARNING: else is not generally useful after a break or return
> > > 1636: FILE: ./rtw_recv.c:1636:
> > > +           return false;
> > > +       else
> > > 
> > > Separated the return statement into a separate block since
> > > it doesn't seem to depend on the SN_LESS explicity being false.
> > > 
> > > Signed-off-by: Sohom <sohom.datta@learner.manipal.edu>
> > > ---
> > >  drivers/staging/rtl8188eu/core/rtw_recv.c | 5 +++--
> > >  1 file changed, 3 insertions(+), 2 deletions(-)
> > > 
> > > diff --git a/drivers/staging/rtl8188eu/core/rtw_recv.c b/drivers/staging/rtl8188eu/core/rtw_recv.c
> > > index 5fe7a0458dd2..5e81134ffb6d 100644
> > > --- a/drivers/staging/rtl8188eu/core/rtw_recv.c
> > > +++ b/drivers/staging/rtl8188eu/core/rtw_recv.c
> > > @@ -1629,10 +1629,11 @@ static int enqueue_reorder_recvframe(struct recv_reorder_ctrl *preorder_ctrl,
> > >  		hdr = list_entry(plist, struct recv_frame, list);
> > >  		pnextattrib = &hdr->attrib;
> > >  
> > > +		if (SN_EQUAL(pnextattrib->seq_num, pattrib->seq_num))
> > > +			return false;
> > > +
> > >  		if (SN_LESS(pnextattrib->seq_num, pattrib->seq_num))
> > >  			plist = plist->next;
> > > -		else if (SN_EQUAL(pnextattrib->seq_num, pattrib->seq_num))
> > > -			return false;
> > >  		else
> > >  			break;
> > >  	}
> > 
> > Checkpatch is just wrong here.  Ignore it when it's wrong.
> 
> It's not "wrong" here.  It's making a suggestion.
> 
> Perhaps read the SN_EQUAL and SN_LESS macros.
> 
> a and b are both u16's here.
> 
> drivers/staging/rtl8188eu/include/rtw_recv.h:#define SN_LESS(a, b)              (((a - b) & 0x800) != 0)
> drivers/staging/rtl8188eu/include/rtw_recv.h:#define SN_EQUAL(a, b)     (a == b)
> 
> Reordering works, perhaps it's just a question of
> whether it's the most likely result of the test.
> 
> This is in a while loop.
> 
> If the expected test is really the most likely that
> SN_LESS is true, then perhaps this loop could be
> something like:
> 
> 		if (SN_LESS(pnextattrib->seq_num, pattrib->seq_num)) {
> 			plist = plist->next;
> 			continue;
> 		}
> 		if (SN_EQUAL(pnextattrib->seq_num, pattrib->seq_num))
> 			return false;
> 		break;
> 	}
> 
> The real question is whether or not that's more readable.
> 

It's not clear to me that any of these are more readable than the other.

I see that someone broke the staging/rtl8712 version of this driver in
June.  See commit 98fe05e21a6e ("staging: rtl8712: Remove unnecesary
else after return statement.").  That patch went through LKML instead of
going through the driver-devel list...  :/

regards,
dan carpenter

Re: [RESEND PATCH] staging: rtl8188eu: Fix else after return WARNING (checkpatch)

[Dan Carpenter]

On Mon, Sep 14, 2020 at 09:42:49AM -0700, Joe Perches wrote:
> On Mon, 2020-09-14 at 17:57 +0300, Dan Carpenter wrote:
> > On Sun, Sep 13, 2020 at 12:19:50PM +0530, Sohom Datta wrote:
> > > > From 4c8c8f3ff7f4d711daea4ac3bb987fcecc7ef1ed Mon Sep 17 00:00:00 2001
> > > From: Sohom <sohom.datta@learner.manipal.edu>
> > > Date: Sat, 12 Sep 2020 18:04:56 +0530
> > > Subject: [RESEND PATCH] staging: rtl8188eu: Fix else after return WARNING
> > >  (checkpatch)
> > > 
> > > Fixed:
> > > WARNING: else is not generally useful after a break or return
> > > 1636: FILE: ./rtw_recv.c:1636:
> > > +           return false;
> > > +       else
> > > 
> > > Separated the return statement into a separate block since
> > > it doesn't seem to depend on the SN_LESS explicity being false.
> > > 
> > > Signed-off-by: Sohom <sohom.datta@learner.manipal.edu>
> > > ---
> > >  drivers/staging/rtl8188eu/core/rtw_recv.c | 5 +++--
> > >  1 file changed, 3 insertions(+), 2 deletions(-)
> > > 
> > > diff --git a/drivers/staging/rtl8188eu/core/rtw_recv.c b/drivers/staging/rtl8188eu/core/rtw_recv.c
> > > index 5fe7a0458dd2..5e81134ffb6d 100644
> > > --- a/drivers/staging/rtl8188eu/core/rtw_recv.c
> > > +++ b/drivers/staging/rtl8188eu/core/rtw_recv.c
> > > @@ -1629,10 +1629,11 @@ static int enqueue_reorder_recvframe(struct recv_reorder_ctrl *preorder_ctrl,
> > >  		hdr = list_entry(plist, struct recv_frame, list);
> > >  		pnextattrib = &hdr->attrib;
> > >  
> > > +		if (SN_EQUAL(pnextattrib->seq_num, pattrib->seq_num))
> > > +			return false;
> > > +
> > >  		if (SN_LESS(pnextattrib->seq_num, pattrib->seq_num))
> > >  			plist = plist->next;
> > > -		else if (SN_EQUAL(pnextattrib->seq_num, pattrib->seq_num))
> > > -			return false;
> > >  		else
> > >  			break;
> > >  	}
> > 
> > Checkpatch is just wrong here.  Ignore it when it's wrong.
> 
> It's not "wrong" here.  It's making a suggestion.
> 
> Perhaps read the SN_EQUAL and SN_LESS macros.
> 
> a and b are both u16's here.
> 
> drivers/staging/rtl8188eu/include/rtw_recv.h:#define SN_LESS(a, b)              (((a - b) & 0x800) != 0)
> drivers/staging/rtl8188eu/include/rtw_recv.h:#define SN_EQUAL(a, b)     (a == b)
> 
> Reordering works, perhaps it's just a question of
> whether it's the most likely result of the test.
> 
> This is in a while loop.
> 
> If the expected test is really the most likely that
> SN_LESS is true, then perhaps this loop could be
> something like:
> 
> 		if (SN_LESS(pnextattrib->seq_num, pattrib->seq_num)) {
> 			plist = plist->next;
> 			continue;
> 		}
> 		if (SN_EQUAL(pnextattrib->seq_num, pattrib->seq_num))
> 			return false;
> 		break;
> 	}
> 
> The real question is whether or not that's more readable.
> 

It's not clear to me that any of these are more readable than the other.

I see that someone broke the staging/rtl8712 version of this driver in
June.  See commit 98fe05e21a6e ("staging: rtl8712: Remove unnecesary
else after return statement.").  That patch went through LKML instead of
going through the driver-devel list...  :/

regards,
dan carpenter

_______________________________________________
devel mailing list
devel@linuxdriverproject.org
http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel

Re: [RESEND PATCH] staging: rtl8188eu: Fix else after return WARNING (checkpatch)

[Joe Perches]

On Tue, 2020-09-15 at 14:20 +0300, Dan Carpenter wrote:
> On Mon, Sep 14, 2020 at 09:42:49AM -0700, Joe Perches wrote:
> > On Mon, 2020-09-14 at 17:57 +0300, Dan Carpenter wrote:
> > > On Sun, Sep 13, 2020 at 12:19:50PM +0530, Sohom Datta wrote:
> > > > > From 4c8c8f3ff7f4d711daea4ac3bb987fcecc7ef1ed Mon Sep 17 00:00:00 2001
> > > > From: Sohom <sohom.datta@learner.manipal.edu>
> > > > Date: Sat, 12 Sep 2020 18:04:56 +0530
> > > > Subject: [RESEND PATCH] staging: rtl8188eu: Fix else after return WARNING
> > > >  (checkpatch)
> > > > 
> > > > Fixed:
> > > > WARNING: else is not generally useful after a break or return
> > > > 1636: FILE: ./rtw_recv.c:1636:
> > > > +           return false;
> > > > +       else
> > > > 
> > > > Separated the return statement into a separate block since
> > > > it doesn't seem to depend on the SN_LESS explicity being false.
> > > > 
> > > > Signed-off-by: Sohom <sohom.datta@learner.manipal.edu>
> > > > ---
> > > >  drivers/staging/rtl8188eu/core/rtw_recv.c | 5 +++--
> > > >  1 file changed, 3 insertions(+), 2 deletions(-)
> > > > 
> > > > diff --git a/drivers/staging/rtl8188eu/core/rtw_recv.c b/drivers/staging/rtl8188eu/core/rtw_recv.c
> > > > index 5fe7a0458dd2..5e81134ffb6d 100644
> > > > --- a/drivers/staging/rtl8188eu/core/rtw_recv.c
> > > > +++ b/drivers/staging/rtl8188eu/core/rtw_recv.c
> > > > @@ -1629,10 +1629,11 @@ static int enqueue_reorder_recvframe(struct recv_reorder_ctrl *preorder_ctrl,
> > > >  		hdr = list_entry(plist, struct recv_frame, list);
> > > >  		pnextattrib = &hdr->attrib;
> > > >  
> > > > +		if (SN_EQUAL(pnextattrib->seq_num, pattrib->seq_num))
> > > > +			return false;
> > > > +
> > > >  		if (SN_LESS(pnextattrib->seq_num, pattrib->seq_num))
> > > >  			plist = plist->next;
> > > > -		else if (SN_EQUAL(pnextattrib->seq_num, pattrib->seq_num))
> > > > -			return false;
> > > >  		else
> > > >  			break;
> > > >  	}
> > > 
> > > Checkpatch is just wrong here.  Ignore it when it's wrong.
> > 
> > It's not "wrong" here.  It's making a suggestion.
> > 
> > Perhaps read the SN_EQUAL and SN_LESS macros.
> > 
> > a and b are both u16's here.
> > 
> > drivers/staging/rtl8188eu/include/rtw_recv.h:#define SN_LESS(a, b)              (((a - b) & 0x800) != 0)
> > drivers/staging/rtl8188eu/include/rtw_recv.h:#define SN_EQUAL(a, b)     (a == b)
> > 
> > Reordering works, perhaps it's just a question of
> > whether it's the most likely result of the test.
> > 
> > This is in a while loop.
> > 
> > If the expected test is really the most likely that
> > SN_LESS is true, then perhaps this loop could be
> > something like:
> > 
> > 		if (SN_LESS(pnextattrib->seq_num, pattrib->seq_num)) {
> > 			plist = plist->next;
> > 			continue;
> > 		}
> > 		if (SN_EQUAL(pnextattrib->seq_num, pattrib->seq_num))
> > 			return false;
> > 		break;
> > 	}
> > 
> > The real question is whether or not that's more readable.
> > 
> 
> It's not clear to me that any of these are more readable than the other.
> 
> I see that someone broke the staging/rtl8712 version of this driver in
> June.  See commit 98fe05e21a6e ("staging: rtl8712: Remove unnecesary
> else after return statement.").  That patch went through LKML instead of
> going through the driver-devel list...  :/

That's sad.

Then another question is whether either is more prone
to unintentional breakage by novice code readers being
guided by brainless scripts...

A bit of a pity as the original intent of the checkpatch
test was somewhat useful.  Maybe it's outlived its value
though when used with -f files.

There aren't many of these left in the kernel.

Maybe it should be changed to work only on patches.

Re: [RESEND PATCH] staging: rtl8188eu: Fix else after return WARNING (checkpatch)

[Joe Perches]

On Tue, 2020-09-15 at 14:20 +0300, Dan Carpenter wrote:
> On Mon, Sep 14, 2020 at 09:42:49AM -0700, Joe Perches wrote:
> > On Mon, 2020-09-14 at 17:57 +0300, Dan Carpenter wrote:
> > > On Sun, Sep 13, 2020 at 12:19:50PM +0530, Sohom Datta wrote:
> > > > > From 4c8c8f3ff7f4d711daea4ac3bb987fcecc7ef1ed Mon Sep 17 00:00:00 2001
> > > > From: Sohom <sohom.datta@learner.manipal.edu>
> > > > Date: Sat, 12 Sep 2020 18:04:56 +0530
> > > > Subject: [RESEND PATCH] staging: rtl8188eu: Fix else after return WARNING
> > > >  (checkpatch)
> > > > 
> > > > Fixed:
> > > > WARNING: else is not generally useful after a break or return
> > > > 1636: FILE: ./rtw_recv.c:1636:
> > > > +           return false;
> > > > +       else
> > > > 
> > > > Separated the return statement into a separate block since
> > > > it doesn't seem to depend on the SN_LESS explicity being false.
> > > > 
> > > > Signed-off-by: Sohom <sohom.datta@learner.manipal.edu>
> > > > ---
> > > >  drivers/staging/rtl8188eu/core/rtw_recv.c | 5 +++--
> > > >  1 file changed, 3 insertions(+), 2 deletions(-)
> > > > 
> > > > diff --git a/drivers/staging/rtl8188eu/core/rtw_recv.c b/drivers/staging/rtl8188eu/core/rtw_recv.c
> > > > index 5fe7a0458dd2..5e81134ffb6d 100644
> > > > --- a/drivers/staging/rtl8188eu/core/rtw_recv.c
> > > > +++ b/drivers/staging/rtl8188eu/core/rtw_recv.c
> > > > @@ -1629,10 +1629,11 @@ static int enqueue_reorder_recvframe(struct recv_reorder_ctrl *preorder_ctrl,
> > > >  		hdr = list_entry(plist, struct recv_frame, list);
> > > >  		pnextattrib = &hdr->attrib;
> > > >  
> > > > +		if (SN_EQUAL(pnextattrib->seq_num, pattrib->seq_num))
> > > > +			return false;
> > > > +
> > > >  		if (SN_LESS(pnextattrib->seq_num, pattrib->seq_num))
> > > >  			plist = plist->next;
> > > > -		else if (SN_EQUAL(pnextattrib->seq_num, pattrib->seq_num))
> > > > -			return false;
> > > >  		else
> > > >  			break;
> > > >  	}
> > > 
> > > Checkpatch is just wrong here.  Ignore it when it's wrong.
> > 
> > It's not "wrong" here.  It's making a suggestion.
> > 
> > Perhaps read the SN_EQUAL and SN_LESS macros.
> > 
> > a and b are both u16's here.
> > 
> > drivers/staging/rtl8188eu/include/rtw_recv.h:#define SN_LESS(a, b)              (((a - b) & 0x800) != 0)
> > drivers/staging/rtl8188eu/include/rtw_recv.h:#define SN_EQUAL(a, b)     (a == b)
> > 
> > Reordering works, perhaps it's just a question of
> > whether it's the most likely result of the test.
> > 
> > This is in a while loop.
> > 
> > If the expected test is really the most likely that
> > SN_LESS is true, then perhaps this loop could be
> > something like:
> > 
> > 		if (SN_LESS(pnextattrib->seq_num, pattrib->seq_num)) {
> > 			plist = plist->next;
> > 			continue;
> > 		}
> > 		if (SN_EQUAL(pnextattrib->seq_num, pattrib->seq_num))
> > 			return false;
> > 		break;
> > 	}
> > 
> > The real question is whether or not that's more readable.
> > 
> 
> It's not clear to me that any of these are more readable than the other.
> 
> I see that someone broke the staging/rtl8712 version of this driver in
> June.  See commit 98fe05e21a6e ("staging: rtl8712: Remove unnecesary
> else after return statement.").  That patch went through LKML instead of
> going through the driver-devel list...  :/

That's sad.

Then another question is whether either is more prone
to unintentional breakage by novice code readers being
guided by brainless scripts...

A bit of a pity as the original intent of the checkpatch
test was somewhat useful.  Maybe it's outlived its value
though when used with -f files.

There aren't many of these left in the kernel.

Maybe it should be changed to work only on patches.


_______________________________________________
devel mailing list
devel@linuxdriverproject.org
http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel