[PATCH] ice: use min() to make code cleaner in ice_gnss

[PATCH] ice: use min() to make code cleaner in ice_gnss

[Wan Jiabing]

Fix the following coccicheck warning:
./drivers/net/ethernet/intel/ice/ice_gnss.c:79:26-27: WARNING opportunity for min()

Use min() to make code cleaner.

Signed-off-by: Wan Jiabing <wanjiabing@vivo.com>
---
 drivers/net/ethernet/intel/ice/ice_gnss.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/intel/ice/ice_gnss.c b/drivers/net/ethernet/intel/ice/ice_gnss.c
index 35579cf4283f..00fd22e813c0 100644
--- a/drivers/net/ethernet/intel/ice/ice_gnss.c
+++ b/drivers/net/ethernet/intel/ice/ice_gnss.c
@@ -76,8 +76,7 @@ static void ice_gnss_read(struct kthread_work *work)
 	for (i = 0; i < data_len; i += bytes_read) {
 		u16 bytes_left = data_len - i;
 
-		bytes_read = bytes_left < ICE_MAX_I2C_DATA_SIZE ? bytes_left :
-					  ICE_MAX_I2C_DATA_SIZE;
+		bytes_read = min(bytes_left, ICE_MAX_I2C_DATA_SIZE);
 
 		err = ice_aq_read_i2c(hw, link_topo, ICE_GNSS_UBX_I2C_BUS_ADDR,
 				      cpu_to_le16(ICE_GNSS_UBX_EMPTY_DATA),
-- 
2.35.1

Re: [PATCH] ice: use min() to make code cleaner in ice_gnss

[Tony Nguyen]

On 3/18/2022 2:46 AM, Wan Jiabing wrote:
> Fix the following coccicheck warning:
> ./drivers/net/ethernet/intel/ice/ice_gnss.c:79:26-27: WARNING opportunity for min()
>
> Use min() to make code cleaner.
>
> Signed-off-by: Wan Jiabing <wanjiabing@vivo.com>

There are build issues with this patch:

In file included from ./include/linux/kernel.h:26,
                  from drivers/net/ethernet/intel/ice/ice.h:9,
                  from drivers/net/ethernet/intel/ice/ice_gnss.c:4:
drivers/net/ethernet/intel/ice/ice_gnss.c: In function ‘ice_gnss_read’:
./include/linux/minmax.h:20:35: error: comparison of distinct pointer 
types lacks a cast [-Werror]
    20 |         (!!(sizeof((typeof(x) *)1 == (typeof(y) *)1)))
       |                                   ^~
./include/linux/minmax.h:26:18: note: in expansion of macro ‘__typecheck’
    26 |                 (__typecheck(x, y) && __no_side_effects(x, y))
       |                  ^~~~~~~~~~~
./include/linux/minmax.h:36:31: note: in expansion of macro ‘__safe_cmp’
    36 |         __builtin_choose_expr(__safe_cmp(x, y), \
       |                               ^~~~~~~~~~
./include/linux/minmax.h:45:25: note: in expansion of macro ‘__careful_cmp’
    45 | #define min(x, y)       __careful_cmp(x, y, <)
       |                         ^~~~~~~~~~~~~
drivers/net/ethernet/intel/ice/ice_gnss.c:79:30: note: in expansion of 
macro ‘min’
    79 |                 bytes_read = min(bytes_left, 
ICE_MAX_I2C_DATA_SIZE);
       |                              ^~~
cc1: all warnings being treated as errors

Re: [PATCH] ice: use min() to make code cleaner in ice_gnss

[Wan Jiabing]

[-- Attachment #1: Type: text/plain, Size: 2101 bytes --]

On Fri, Mar 18, 2022 at 01:19:26PM -0700, Tony Nguyen wrote:
> 
> On 3/18/2022 2:46 AM, Wan Jiabing wrote:
> > Fix the following coccicheck warning:
> > ./drivers/net/ethernet/intel/ice/ice_gnss.c:79:26-27: WARNING opportunity for min()
> > 
> > Use min() to make code cleaner.
> > 
> > Signed-off-by: Wan Jiabing <wanjiabing@vivo.com>
> 
> There are build issues with this patch:
> 
> In file included from ./include/linux/kernel.h:26,
>                  from drivers/net/ethernet/intel/ice/ice.h:9,
>                  from drivers/net/ethernet/intel/ice/ice_gnss.c:4:
> drivers/net/ethernet/intel/ice/ice_gnss.c: In function ‘ice_gnss_read’:
> ./include/linux/minmax.h:20:35: error: comparison of distinct pointer types
> lacks a cast [-Werror]
>    20 |         (!!(sizeof((typeof(x) *)1 == (typeof(y) *)1)))
>       |                                   ^~
> ./include/linux/minmax.h:26:18: note: in expansion of macro ‘__typecheck’
>    26 |                 (__typecheck(x, y) && __no_side_effects(x, y))
>       |                  ^~~~~~~~~~~
> ./include/linux/minmax.h:36:31: note: in expansion of macro ‘__safe_cmp’
>    36 |         __builtin_choose_expr(__safe_cmp(x, y), \
>       |                               ^~~~~~~~~~
> ./include/linux/minmax.h:45:25: note: in expansion of macro ‘__careful_cmp’
>    45 | #define min(x, y)       __careful_cmp(x, y, <)
>       |                         ^~~~~~~~~~~~~
> drivers/net/ethernet/intel/ice/ice_gnss.c:79:30: note: in expansion of macro
> ‘min’
>    79 |                 bytes_read = min(bytes_left, ICE_MAX_I2C_DATA_SIZE);
>       |                              ^~~
> cc1: all warnings being treated as errors
> 

Yes, sorry for the warning.

After check minmax.h, it's better to use min_t and there are no warnings.

Please check the new patch, thanks!

Wan Jiabing

[-- Attachment #2: 0001-ice-use-min_t-to-make-code-cleaner-in-ice_gnss.patch --]
[-- Type: text/plain, Size: 1171 bytes --]

From 43118a4f14393816054a41e4861106cdb623b3d9 Mon Sep 17 00:00:00 2001
From: Wan Jiabing <wanjiabing@vivo.com>
Date: Sat, 19 Mar 2022 12:01:29 +0800
Subject: [PATCH] ice: use min_t() to make code cleaner in ice_gnss

Fix the following coccicheck warning:
./drivers/net/ethernet/intel/ice/ice_gnss.c:79:26-27: WARNING opportunity for min()

Signed-off-by: Wan Jiabing <wanjiabing@vivo.com>
---
 drivers/net/ethernet/intel/ice/ice_gnss.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/intel/ice/ice_gnss.c b/drivers/net/ethernet/intel/ice/ice_gnss.c
index 35579cf4283f..85ceb7018781 100644
--- a/drivers/net/ethernet/intel/ice/ice_gnss.c
+++ b/drivers/net/ethernet/intel/ice/ice_gnss.c
@@ -76,8 +76,7 @@ static void ice_gnss_read(struct kthread_work *work)
 	for (i = 0; i < data_len; i += bytes_read) {
 		u16 bytes_left = data_len - i;
 
-		bytes_read = bytes_left < ICE_MAX_I2C_DATA_SIZE ? bytes_left :
-					  ICE_MAX_I2C_DATA_SIZE;
+		bytes_read = min_t(u8, bytes_left, ICE_MAX_I2C_DATA_SIZE);
 
 		err = ice_aq_read_i2c(hw, link_topo, ICE_GNSS_UBX_I2C_BUS_ADDR,
 				      cpu_to_le16(ICE_GNSS_UBX_EMPTY_DATA),
-- 
2.35.1

Re: [Intel-wired-lan] [PATCH] ice: use min() to make code cleaner in ice_gnss

[Alexander Lobakin]

From: Tony Nguyen <anthony.l.nguyen@intel.com>
Date: Fri, 18 Mar 2022 13:19:26 -0700

> On 3/18/2022 2:46 AM, Wan Jiabing wrote:

Hey Wan,

> > Fix the following coccicheck warning:
> > ./drivers/net/ethernet/intel/ice/ice_gnss.c:79:26-27: WARNING opportunity for min()
> >
> > Use min() to make code cleaner.
> >
> > Signed-off-by: Wan Jiabing <wanjiabing@vivo.com>
> 
> There are build issues with this patch:
> 
> In file included from ./include/linux/kernel.h:26,
>                  from drivers/net/ethernet/intel/ice/ice.h:9,
>                  from drivers/net/ethernet/intel/ice/ice_gnss.c:4:
> drivers/net/ethernet/intel/ice/ice_gnss.c: In function 'ice_gnss_read':
> ./include/linux/minmax.h:20:35: error: comparison of distinct pointer types lacks a cast [-Werror]
>    20 |         (!!(sizeof((typeof(x) *)1 == (typeof(y) *)1)))
>       |                                   ^~
> ./include/linux/minmax.h:26:18: note: in expansion of macro '__typecheck'
>    26 |                 (__typecheck(x, y) && __no_side_effects(x, y))
>       |                  ^~~~~~~~~~~
> ./include/linux/minmax.h:36:31: note: in expansion of macro '__safe_cmp'
>    36 |         __builtin_choose_expr(__safe_cmp(x, y), \
>       |                               ^~~~~~~~~~
> ./include/linux/minmax.h:45:25: note: in expansion of macro '__careful_cmp'
>    45 | #define min(x, y)       __careful_cmp(x, y, <)
>       |                         ^~~~~~~~~~~~~
> drivers/net/ethernet/intel/ice/ice_gnss.c:79:30: note: in expansion of macro 'min'
>    79 |                 bytes_read = min(bytes_left, ICE_MAX_I2C_DATA_SIZE);
>       |                              ^~~

Use `min_t(typeof(bytes_left), ICE_MAX_I2C_DATA_SIZE)` to avoid
this. Plain definitions are usually treated as `unsigned long`
unless there's a suffix (u, ull etc.).

> cc1: all warnings being treated as errors 

Thanks,
Al

Re: [Intel-wired-lan] [PATCH] ice: use min() to make code cleaner in ice_gnss

[Jiabing Wan]

On 2022/3/21 19:54, Alexander Lobakin wrote:
> From: Tony Nguyen <anthony.l.nguyen@intel.com>
> Date: Fri, 18 Mar 2022 13:19:26 -0700
>
>> On 3/18/2022 2:46 AM, Wan Jiabing wrote:
> Hey Wan,
>
>>> Fix the following coccicheck warning:
>>> ./drivers/net/ethernet/intel/ice/ice_gnss.c:79:26-27: WARNING opportunity for min()
>>>
>>> Use min() to make code cleaner.
>>>
>>> Signed-off-by: Wan Jiabing <wanjiabing@vivo.com>
>> There are build issues with this patch:
>>
>> In file included from ./include/linux/kernel.h:26,
>>                   from drivers/net/ethernet/intel/ice/ice.h:9,
>>                   from drivers/net/ethernet/intel/ice/ice_gnss.c:4:
>> drivers/net/ethernet/intel/ice/ice_gnss.c: In function 'ice_gnss_read':
>> ./include/linux/minmax.h:20:35: error: comparison of distinct pointer types lacks a cast [-Werror]
>>     20 |         (!!(sizeof((typeof(x) *)1 == (typeof(y) *)1)))
>>        |                                   ^~
>> ./include/linux/minmax.h:26:18: note: in expansion of macro '__typecheck'
>>     26 |                 (__typecheck(x, y) && __no_side_effects(x, y))
>>        |                  ^~~~~~~~~~~
>> ./include/linux/minmax.h:36:31: note: in expansion of macro '__safe_cmp'
>>     36 |         __builtin_choose_expr(__safe_cmp(x, y), \
>>        |                               ^~~~~~~~~~
>> ./include/linux/minmax.h:45:25: note: in expansion of macro '__careful_cmp'
>>     45 | #define min(x, y)       __careful_cmp(x, y, <)
>>        |                         ^~~~~~~~~~~~~
>> drivers/net/ethernet/intel/ice/ice_gnss.c:79:30: note: in expansion of macro 'min'
>>     79 |                 bytes_read = min(bytes_left, ICE_MAX_I2C_DATA_SIZE);
>>        |                              ^~~
> Use `min_t(typeof(bytes_left), ICE_MAX_I2C_DATA_SIZE)` to avoid
> this. Plain definitions are usually treated as `unsigned long`
> unless there's a suffix (u, ull etc.).
>
>> cc1: all warnings being treated as errors
> Thanks,
> Al

OK, I'll fix it in v2.

Thanks,
Wan Jiabing

RE: [Intel-wired-lan] [PATCH] ice: use min() to make code cleaner in ice_gnss

[David Laight]

> Use `min_t(typeof(bytes_left), ICE_MAX_I2C_DATA_SIZE)` to avoid
> this. Plain definitions are usually treated as `unsigned long`
> unless there's a suffix (u, ull etc.).

I suspect they are 'int'.
And the compiler will convert to 'unsigned int' in any
arithmetic.
And the 'signed v unsigned' compare warning is supressed
to integer constants.

	David

-
Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK
Registration No: 1397386 (Wales)