Re: [PATCH] arch/h8300: modify ffs(), fls() etc. functions to return int
From: Randy Dunlap
Date: Sun Jul 22 2018 - 14:02:31 EST
On 07/22/2018 02:25 AM, Geert Uytterhoeven wrote:
> CC hexagon
>
> hexagon != H8/300 != SuperH
>
> On Sat, Jul 21, 2018 at 5:28 AM Randy Dunlap <rdunlap@xxxxxxxxxxxxx> wrote:
>>
>> From: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
>>
>> Building drivers/mtd/nand/raw/nandsim.c on arch/hexagon/ produces a
>> printk format build warning. This is due to hexagon's ffs() being
>> coded as returning long instead of int.
>>
>> Fix the printk format warning by changing all of hexagon's ffx() and
>> flx() functions to return int instead of long. The variables that
>> they return are already int instead of long.
>>
>> ../drivers/mtd/nand/raw/nandsim.c: In function 'init_nandsim':
>> ../drivers/mtd/nand/raw/nandsim.c:760:2: warning: format '%u' expects argument of type 'unsigned int', but argument 2 has type 'long int' [-Wformat]
>>
>>
>> There are no ffx() or flx() allmodconfig build errors after making this
>> change.
>>
>> Signed-off-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
>> Cc: Yoshinori Sato <ysato@xxxxxxxxxxxxxxxxxxxx>
>> Cc: Rich Felker <dalias@xxxxxxxx>
>> Cc: linux-sh@xxxxxxxxxxxxxxx
>> ---
>> arch/hexagon/include/asm/bitops.h | 10 +++++-----
>> 1 file changed, 5 insertions(+), 5 deletions(-)
>>
>> --- linux-next-20180717.orig/arch/hexagon/include/asm/bitops.h
>> +++ linux-next-20180717/arch/hexagon/include/asm/bitops.h
>> @@ -194,7 +194,7 @@ static inline int __test_bit(int nr, con
>> *
>> * Undefined if no zero exists, so code should check against ~0UL first.
>> */
>> -static inline long ffz(int x)
>> +static inline int ffz(int x)
>> {
>> int r;
>>
>> @@ -211,7 +211,7 @@ static inline long ffz(int x)
>> * This is defined the same way as ffs.
>> * Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32.
>> */
>> -static inline long fls(int x)
>> +static inline int fls(int x)
>> {
>> int r;
>>
>> @@ -232,7 +232,7 @@ static inline long fls(int x)
>> * the libc and compiler builtin ffs routines, therefore
>> * differs in spirit from the above ffz (man ffs).
>> */
>> -static inline long ffs(int x)
>> +static inline int ffs(int x)
>> {
>> int r;
>>
>> @@ -254,7 +254,7 @@ static inline long ffs(int x)
>> * bits_per_long assumed to be 32
>> * numbering starts at 0 I think (instead of 1 like ffs)
>> */
>> -static inline unsigned long __ffs(unsigned long word)
>> +static inline int __ffs(unsigned long word)
>
> The version in asm-generic deoes use "unsigned long".
>
> See also "m68k/bitops: convert __ffs to match generic declaration"
> https://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k.git/commit/?h=for-v4.19&id=4b538d3dca3e590cdb0234746011a6d9c245cfa3
>
>> {
>> int num;
>>
>> @@ -272,7 +272,7 @@ static inline unsigned long __ffs(unsign
>> * Undefined if no set bit exists, so code should check against 0 first.
>> * bits_per_long assumed to be 32
>> */
>> -static inline unsigned long __fls(unsigned long word)
>> +static inline int __fls(unsigned long word)
>
> Same here
Hi Geert,
Thanks for all your catches here. So ffs() and fls() return int,
while __ffs() and __fls() return unsigned long.
(hm, arch/arc/include/asm/bitops.h is a little different.)
(and unicore32)
I'll send a v2 patch (for hexagon).
That will still fix the printk format warning above.
>> {
>> int num;
--
~Randy