2023-03-18 17:53:03

by Sumitra Sharma

[permalink] [raw]
Subject: [PATCH v2] Staging: nvec: Convert to_nvec_led from a macro to an inline function

Convert to_nvec_led from a macro to a static inline function, to make the
relevant types apparent in the definition and to benefit from the type
checking performed by the compiler at call sites.

Signed-off-by: Sumitra Sharma <[email protected]>
---

v2: Change patch subject and description, noted by
Julia Lawall <[email protected]>

drivers/staging/nvec/nvec_paz00.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/staging/nvec/nvec_paz00.c b/drivers/staging/nvec/nvec_paz00.c
index 8b4da95081c8..9573ba762cdd 100644
--- a/drivers/staging/nvec/nvec_paz00.c
+++ b/drivers/staging/nvec/nvec_paz00.c
@@ -14,8 +14,10 @@
#include <linux/platform_device.h>
#include "nvec.h"

-#define to_nvec_led(led_cdev) \
- container_of(led_cdev, struct nvec_led, cdev)
+static inline struct nvec_led *to_nvec_led(struct led_classdev *led_cdev)
+{
+ return container_of(led_cdev, struct nvec_led, cdev);
+}

#define NVEC_LED_REQ {'\x0d', '\x10', '\x45', '\x10', '\x00'}

--
2.25.1



2023-03-20 05:40:03

by Dan Carpenter

[permalink] [raw]
Subject: Re: [PATCH v2] Staging: nvec: Convert to_nvec_led from a macro to an inline function

On Sat, Mar 18, 2023 at 10:52:50AM -0700, Sumitra Sharma wrote:
> Convert to_nvec_led from a macro to a static inline function, to make the
> relevant types apparent in the definition and to benefit from the type
> checking performed by the compiler at call sites.
>
> Signed-off-by: Sumitra Sharma <[email protected]>
> ---

You need to compile test your changes.

regards,
dan carpenter


2023-03-20 08:44:36

by Sumitra Sharma

[permalink] [raw]
Subject: Re: [PATCH v2] Staging: nvec: Convert to_nvec_led from a macro to an inline function

On Mon, Mar 20, 2023 at 08:39:49AM +0300, Dan Carpenter wrote:
> On Sat, Mar 18, 2023 at 10:52:50AM -0700, Sumitra Sharma wrote:
> > Convert to_nvec_led from a macro to a static inline function, to make the
> > relevant types apparent in the definition and to benefit from the type
> > checking performed by the compiler at call sites.
> >
> > Signed-off-by: Sumitra Sharma <[email protected]>
> > ---
>
> You need to compile test your changes.
>

Hi dan,

I am facing problems in creating modules and in compiling them.

Any help in this would be appreciated. Here is the link to the thread https://lore.kernel.org/outreachy/alpine.DEB.2.22.394.2303191336090.2867@hadrien/T/#t

Regards,

Sumitra

> regards,
> dan carpenter
>

2023-03-20 08:58:28

by Dan Carpenter

[permalink] [raw]
Subject: Re: [PATCH v2] Staging: nvec: Convert to_nvec_led from a macro to an inline function

On Mon, Mar 20, 2023 at 01:44:22AM -0700, Sumitra Sharma wrote:
> On Mon, Mar 20, 2023 at 08:39:49AM +0300, Dan Carpenter wrote:
> > On Sat, Mar 18, 2023 at 10:52:50AM -0700, Sumitra Sharma wrote:
> > > Convert to_nvec_led from a macro to a static inline function, to make the
> > > relevant types apparent in the definition and to benefit from the type
> > > checking performed by the compiler at call sites.
> > >
> > > Signed-off-by: Sumitra Sharma <[email protected]>
> > > ---
> >
> > You need to compile test your changes.
> >
>
> Hi dan,
>
> I am facing problems in creating modules and in compiling them.
>
> Any help in this would be appreciated. Here is the link to the thread
> https://lore.kernel.org/outreachy/alpine.DEB.2.22.394.2303191336090.2867@hadrien/T/#t

If you're editing a .h file then you need to compile all the stuff which
includes it. It's slightly complicated. But if you're just editing a
.c file like here then what I do is I have use my Smatch script to try
compile it.

In Debian run:
apt-get install gcc make sqlite3 libsqlite3-dev libdbd-sqlite3-perl libssl-dev libtry-tiny-perl
Or in Fedora run:
yum install gcc make sqlite3 sqlite-devel sqlite perl-DBD-SQLite openssl-devel perl-Try-Tiny

git clone https://github.com/error27/smatch.git
cd smatch
make

cd /path/to/kernel_src/
~/smatch/smatch_scripts/kchecker drivers/staging/nvec/nvec_paz00.c

Also I run Sparse on the file.
~/smatch/smatch_scripts/kchecker --sparse drivers/staging/nvec/nvec_paz00.c

When I'm patching a file, then I like to look at any other issues I
might want to fix and deal with that as well.

regards,
dan carpenter

2023-03-20 09:07:11

by Julia Lawall

[permalink] [raw]
Subject: Re: [PATCH v2] Staging: nvec: Convert to_nvec_led from a macro to an inline function



On Mon, 20 Mar 2023, Sumitra Sharma wrote:

> On Mon, Mar 20, 2023 at 08:39:49AM +0300, Dan Carpenter wrote:
> > On Sat, Mar 18, 2023 at 10:52:50AM -0700, Sumitra Sharma wrote:
> > > Convert to_nvec_led from a macro to a static inline function, to make the
> > > relevant types apparent in the definition and to benefit from the type
> > > checking performed by the compiler at call sites.
> > >
> > > Signed-off-by: Sumitra Sharma <[email protected]>
> > > ---
> >
> > You need to compile test your changes.
> >
>
> Hi dan,
>
> I am facing problems in creating modules and in compiling them.

Note that unless the code is under an ifdef for a module, you don't
specifically need the driver to be configured as for a module either.
Since you don't have the device, you aren't going to be able to test it
anyway. So 'y' is fine.

julia

>
> Any help in this would be appreciated. Here is the link to the thread https://lore.kernel.org/outreachy/alpine.DEB.2.22.394.2303191336090.2867@hadrien/T/#t
>
> Regards,
>
> Sumitra
>
> > regards,
> > dan carpenter
> >
>
>

2023-03-20 15:37:28

by kernel test robot

[permalink] [raw]
Subject: Re: [PATCH v2] Staging: nvec: Convert to_nvec_led from a macro to an inline function

Hi Sumitra,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on staging/staging-testing]

url: https://github.com/intel-lab-lkp/linux/commits/Sumitra-Sharma/Staging-nvec-Convert-to_nvec_led-from-a-macro-to-an-inline-function/20230319-015434
patch link: https://lore.kernel.org/r/20230318175250.GA49618%40sumitra.com
patch subject: [PATCH v2] Staging: nvec: Convert to_nvec_led from a macro to an inline function
config: arm-allyesconfig (https://download.01.org/0day-ci/archive/20230320/[email protected]/config)
compiler: arm-linux-gnueabi-gcc (GCC) 12.1.0
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# https://github.com/intel-lab-lkp/linux/commit/5bb6b930cab3ac631310d3bbf40c9decf91dfd38
git remote add linux-review https://github.com/intel-lab-lkp/linux
git fetch --no-tags linux-review Sumitra-Sharma/Staging-nvec-Convert-to_nvec_led-from-a-macro-to-an-inline-function/20230319-015434
git checkout 5bb6b930cab3ac631310d3bbf40c9decf91dfd38
# save the config file
mkdir build_dir && cp config build_dir/.config
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=arm olddefconfig
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=arm SHELL=/bin/bash drivers/staging/

If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <[email protected]>
| Link: https://lore.kernel.org/oe-kbuild-all/[email protected]/

All errors (new ones prefixed by >>):

In file included from include/linux/container_of.h:5,
from include/linux/list.h:5,
from include/linux/module.h:12,
from drivers/staging/nvec/nvec_paz00.c:10:
drivers/staging/nvec/nvec_paz00.c: In function 'to_nvec_led':
>> include/linux/container_of.h:20:54: error: invalid use of undefined type 'struct nvec_led'
20 | static_assert(__same_type(*(ptr), ((type *)0)->member) || \
| ^~
include/linux/build_bug.h:78:56: note: in definition of macro '__static_assert'
78 | #define __static_assert(expr, msg, ...) _Static_assert(expr, msg)
| ^~~~
include/linux/container_of.h:20:9: note: in expansion of macro 'static_assert'
20 | static_assert(__same_type(*(ptr), ((type *)0)->member) || \
| ^~~~~~~~~~~~~
include/linux/container_of.h:20:23: note: in expansion of macro '__same_type'
20 | static_assert(__same_type(*(ptr), ((type *)0)->member) || \
| ^~~~~~~~~~~
drivers/staging/nvec/nvec_paz00.c:19:16: note: in expansion of macro 'container_of'
19 | return container_of(led_cdev, struct nvec_led, cdev);
| ^~~~~~~~~~~~
include/linux/compiler_types.h:338:27: error: expression in static assertion is not an integer
338 | #define __same_type(a, b) __builtin_types_compatible_p(typeof(a), typeof(b))
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/build_bug.h:78:56: note: in definition of macro '__static_assert'
78 | #define __static_assert(expr, msg, ...) _Static_assert(expr, msg)
| ^~~~
include/linux/container_of.h:20:9: note: in expansion of macro 'static_assert'
20 | static_assert(__same_type(*(ptr), ((type *)0)->member) || \
| ^~~~~~~~~~~~~
include/linux/container_of.h:20:23: note: in expansion of macro '__same_type'
20 | static_assert(__same_type(*(ptr), ((type *)0)->member) || \
| ^~~~~~~~~~~
drivers/staging/nvec/nvec_paz00.c:19:16: note: in expansion of macro 'container_of'
19 | return container_of(led_cdev, struct nvec_led, cdev);
| ^~~~~~~~~~~~
In file included from include/uapi/linux/posix_types.h:5,
from include/uapi/linux/types.h:14,
from include/linux/types.h:6,
from include/linux/kasan-checks.h:5,
from include/asm-generic/rwonce.h:26,
from ./arch/arm/include/generated/asm/rwonce.h:1,
from include/linux/compiler.h:247,
from include/linux/build_bug.h:5:
>> include/linux/stddef.h:16:33: error: invalid use of undefined type 'struct nvec_led'
16 | #define offsetof(TYPE, MEMBER) __builtin_offsetof(TYPE, MEMBER)
| ^~~~~~~~~~~~~~~~~~
include/linux/container_of.h:23:28: note: in expansion of macro 'offsetof'
23 | ((type *)(__mptr - offsetof(type, member))); })
| ^~~~~~~~
drivers/staging/nvec/nvec_paz00.c:19:16: note: in expansion of macro 'container_of'
19 | return container_of(led_cdev, struct nvec_led, cdev);
| ^~~~~~~~~~~~
drivers/staging/nvec/nvec_paz00.c:20:1: error: control reaches end of non-void function [-Werror=return-type]
20 | }
| ^
cc1: some warnings being treated as errors


vim +20 include/linux/container_of.h

d2a8ebbf8192b8 Andy Shevchenko 2021-11-08 9
d2a8ebbf8192b8 Andy Shevchenko 2021-11-08 10 /**
d2a8ebbf8192b8 Andy Shevchenko 2021-11-08 11 * container_of - cast a member of a structure out to the containing structure
d2a8ebbf8192b8 Andy Shevchenko 2021-11-08 12 * @ptr: the pointer to the member.
d2a8ebbf8192b8 Andy Shevchenko 2021-11-08 13 * @type: the type of the container struct this is embedded in.
d2a8ebbf8192b8 Andy Shevchenko 2021-11-08 14 * @member: the name of the member within the struct.
d2a8ebbf8192b8 Andy Shevchenko 2021-11-08 15 *
7376e561fd2e01 Sakari Ailus 2022-10-24 16 * WARNING: any const qualifier of @ptr is lost.
d2a8ebbf8192b8 Andy Shevchenko 2021-11-08 17 */
d2a8ebbf8192b8 Andy Shevchenko 2021-11-08 18 #define container_of(ptr, type, member) ({ \
d2a8ebbf8192b8 Andy Shevchenko 2021-11-08 19 void *__mptr = (void *)(ptr); \
e1edc277e6f6df Rasmus Villemoes 2021-11-08 @20 static_assert(__same_type(*(ptr), ((type *)0)->member) || \
e1edc277e6f6df Rasmus Villemoes 2021-11-08 21 __same_type(*(ptr), void), \
d2a8ebbf8192b8 Andy Shevchenko 2021-11-08 22 "pointer type mismatch in container_of()"); \
d2a8ebbf8192b8 Andy Shevchenko 2021-11-08 23 ((type *)(__mptr - offsetof(type, member))); })
d2a8ebbf8192b8 Andy Shevchenko 2021-11-08 24

--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests

2023-03-20 15:55:44

by Greg Kroah-Hartman

[permalink] [raw]
Subject: Re: [PATCH v2] Staging: nvec: Convert to_nvec_led from a macro to an inline function

On Sat, Mar 18, 2023 at 10:52:50AM -0700, Sumitra Sharma wrote:
> Convert to_nvec_led from a macro to a static inline function, to make the
> relevant types apparent in the definition and to benefit from the type
> checking performed by the compiler at call sites.
>
> Signed-off-by: Sumitra Sharma <[email protected]>
> ---
>
> v2: Change patch subject and description, noted by
> Julia Lawall <[email protected]>
>
> drivers/staging/nvec/nvec_paz00.c | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/staging/nvec/nvec_paz00.c b/drivers/staging/nvec/nvec_paz00.c
> index 8b4da95081c8..9573ba762cdd 100644
> --- a/drivers/staging/nvec/nvec_paz00.c
> +++ b/drivers/staging/nvec/nvec_paz00.c
> @@ -14,8 +14,10 @@
> #include <linux/platform_device.h>
> #include "nvec.h"
>
> -#define to_nvec_led(led_cdev) \
> - container_of(led_cdev, struct nvec_led, cdev)
> +static inline struct nvec_led *to_nvec_led(struct led_classdev *led_cdev)
> +{
> + return container_of(led_cdev, struct nvec_led, cdev);
> +}

There is no need for a function, or a macro, for this, as it is only
used once. Please just open-code it in the one place it is used
instead.

thanks,

greg k-h