[PATCH] mm: fixmap: convert __set_fixmap_offset() to an inline function

[PATCH] mm: fixmap: convert __set_fixmap_offset() to an inline function

[Masahiro Yamada]

I just stopped by the ugly variable name, ________addr.
(8 underscores!)

If this is just a matter of casting to (unsigned long), this variable
is unneeded since you can do like this:

({                                                                      \
        __set_fixmap(idx, phys, flags);                                 \
        (unsigned long)(fix_to_virt(idx) + ((phys) & (PAGE_SIZE - 1))); \
})

However, I'd rather like to change it to an inline function since it
is more readable, and the parameter types are clearer.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
---

 include/asm-generic/fixmap.h | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/include/asm-generic/fixmap.h b/include/asm-generic/fixmap.h
index 8cc7b09c1bc7..de4c36912529 100644
--- a/include/asm-generic/fixmap.h
+++ b/include/asm-generic/fixmap.h
@@ -70,14 +70,14 @@ static inline unsigned long virt_to_fix(const unsigned long vaddr)
 	__set_fixmap(idx, 0, FIXMAP_PAGE_CLEAR)
 #endif
 
-/* Return a pointer with offset calculated */
-#define __set_fixmap_offset(idx, phys, flags)				\
-({									\
-	unsigned long ________addr;					\
-	__set_fixmap(idx, phys, flags);					\
-	________addr = fix_to_virt(idx) + ((phys) & (PAGE_SIZE - 1));	\
-	________addr;							\
-})
+/* Return a virtual address with offset calculated */
+static inline unsigned long __set_fixmap_offset(enum fixed_addresses idx,
+						phys_addr_t phys,
+						pgprot_t flags)
+{
+	__set_fixmap(idx, phys, flags);
+	return fix_to_virt(idx) + ((phys) & (PAGE_SIZE - 1));
+}
 
 #define set_fixmap_offset(idx, phys) \
 	__set_fixmap_offset(idx, phys, FIXMAP_PAGE_NORMAL)
-- 
2.17.1

Re: [PATCH] mm: fixmap: convert __set_fixmap_offset() to an inline function

[kbuild test robot]

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Hi Masahiro,

I love your patch! Perhaps something to improve:

[auto build test WARNING on mmotm/master]
[also build test WARNING on v5.4-rc6 next-20191108]
[if your patch is applied to the wrong git tree, please drop us a note to help
improve the system. BTW, we also suggest to use '--base' option to specify the
base tree in git format-patch, please see https://stackoverflow.com/a/37406982]

url:    https://github.com/0day-ci/linux/commits/Masahiro-Yamada/mm-fixmap-convert-__set_fixmap_offset-to-an-inline-function/20191110-045158
base:   git://git.cmpxchg.org/linux-mmotm.git master
config: powerpc-allnoconfig (attached as .config)
compiler: powerpc-linux-gcc (GCC) 7.4.0
reproduce:
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # save the attached .config to linux build tree
        GCC_VERSION=7.4.0 make.cross ARCH=powerpc 

If you fix the issue, kindly add following tag
Reported-by: kbuild test robot <lkp@intel.com>

All warnings (new ones prefixed by >>):

   In file included from arch/powerpc/include/asm/fixmap.h:75:0,
                    from arch/powerpc/include/asm/book3s/32/pgtable.h:149,
                    from arch/powerpc/include/asm/book3s/pgtable.h:8,
                    from arch/powerpc/include/asm/pgtable.h:18,
                    from arch/powerpc/include/asm/kup.h:30,
                    from arch/powerpc/include/asm/uaccess.h:9,
                    from include/linux/uaccess.h:11,
                    from include/linux/crypto.h:21,
                    from include/crypto/hash.h:11,
                    from include/linux/uio.h:10,
                    from include/linux/socket.h:8,
                    from include/linux/compat.h:15,
                    from arch/powerpc/kernel/asm-offsets.c:14:
   include/asm-generic/fixmap.h: In function '__set_fixmap_offset':
   include/asm-generic/fixmap.h:78:2: error: implicit declaration of function '__set_fixmap'; did you mean 'set_fixmap'? [-Werror=implicit-function-declaration]
     __set_fixmap(idx, phys, flags);
     ^~~~~~~~~~~~
     set_fixmap
   In file included from arch/powerpc/include/asm/book3s/32/pgtable.h:149:0,
                    from arch/powerpc/include/asm/book3s/pgtable.h:8,
                    from arch/powerpc/include/asm/pgtable.h:18,
                    from arch/powerpc/include/asm/kup.h:30,
                    from arch/powerpc/include/asm/uaccess.h:9,
                    from include/linux/uaccess.h:11,
                    from include/linux/crypto.h:21,
                    from include/crypto/hash.h:11,
                    from include/linux/uio.h:10,
                    from include/linux/socket.h:8,
                    from include/linux/compat.h:15,
                    from arch/powerpc/kernel/asm-offsets.c:14:
   arch/powerpc/include/asm/fixmap.h: At top level:
>> arch/powerpc/include/asm/fixmap.h:77:20: warning: conflicting types for '__set_fixmap'
    static inline void __set_fixmap(enum fixed_addresses idx,
                       ^~~~~~~~~~~~
   arch/powerpc/include/asm/fixmap.h:77:20: error: static declaration of '__set_fixmap' follows non-static declaration
   In file included from arch/powerpc/include/asm/fixmap.h:75:0,
                    from arch/powerpc/include/asm/book3s/32/pgtable.h:149,
                    from arch/powerpc/include/asm/book3s/pgtable.h:8,
                    from arch/powerpc/include/asm/pgtable.h:18,
                    from arch/powerpc/include/asm/kup.h:30,
                    from arch/powerpc/include/asm/uaccess.h:9,
                    from include/linux/uaccess.h:11,
                    from include/linux/crypto.h:21,
                    from include/crypto/hash.h:11,
                    from include/linux/uio.h:10,
                    from include/linux/socket.h:8,
                    from include/linux/compat.h:15,
                    from arch/powerpc/kernel/asm-offsets.c:14:
   include/asm-generic/fixmap.h:78:2: note: previous implicit declaration of '__set_fixmap' was here
     __set_fixmap(idx, phys, flags);
     ^~~~~~~~~~~~
   cc1: some warnings being treated as errors
   make[2]: *** [arch/powerpc/kernel/asm-offsets.s] Error 1
   make[2]: Target '__build' not remade because of errors.
   make[1]: *** [prepare0] Error 2
   make[1]: Target 'prepare' not remade because of errors.
   make: *** [sub-make] Error 2
   17 real  5 user  2 sys  44.62% cpu 	make prepare

vim +/__set_fixmap +77 arch/powerpc/include/asm/fixmap.h

2c419bdeca1d95 include/asm-powerpc/fixmap.h      Kumar Gala       2008-04-23  76  
4cfac2f9c7f116 arch/powerpc/include/asm/fixmap.h Christophe Leroy 2017-08-02 @77  static inline void __set_fixmap(enum fixed_addresses idx,
4cfac2f9c7f116 arch/powerpc/include/asm/fixmap.h Christophe Leroy 2017-08-02  78  				phys_addr_t phys, pgprot_t flags)
4cfac2f9c7f116 arch/powerpc/include/asm/fixmap.h Christophe Leroy 2017-08-02  79  {
c766ee72235d09 arch/powerpc/include/asm/fixmap.h Christophe Leroy 2018-10-09  80  	map_kernel_page(fix_to_virt(idx), phys, flags);
4cfac2f9c7f116 arch/powerpc/include/asm/fixmap.h Christophe Leroy 2017-08-02  81  }
4cfac2f9c7f116 arch/powerpc/include/asm/fixmap.h Christophe Leroy 2017-08-02  82  

:::::: The code at line 77 was first introduced by commit
:::::: 4cfac2f9c7f116af8516d0b3d0e7383189eca376 powerpc/mm: Simplify __set_fixmap()

:::::: TO: Christophe Leroy <christophe.leroy@c-s.fr>
:::::: CC: Michael Ellerman <mpe@ellerman.id.au>

---
0-DAY kernel test infrastructure                 Open Source Technology Center
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org Intel Corporation

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Re: [PATCH] mm: fixmap: convert __set_fixmap_offset() to an inline function

[kbuild test robot]

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Hi Masahiro,

I love your patch! Yet something to improve:

[auto build test ERROR on mmotm/master]
[also build test ERROR on v5.4-rc6 next-20191108]
[if your patch is applied to the wrong git tree, please drop us a note to help
improve the system. BTW, we also suggest to use '--base' option to specify the
base tree in git format-patch, please see https://stackoverflow.com/a/37406982]

url:    https://github.com/0day-ci/linux/commits/Masahiro-Yamada/mm-fixmap-convert-__set_fixmap_offset-to-an-inline-function/20191110-045158
base:   git://git.cmpxchg.org/linux-mmotm.git master
config: powerpc-defconfig (attached as .config)
compiler: powerpc64-linux-gcc (GCC) 7.4.0
reproduce:
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # save the attached .config to linux build tree
        GCC_VERSION=7.4.0 make.cross ARCH=powerpc 

If you fix the issue, kindly add following tag
Reported-by: kbuild test robot <lkp@intel.com>

All errors (new ones prefixed by >>):

   In file included from arch/powerpc/include/asm/fixmap.h:75:0,
                    from arch/powerpc/mm/mem.c:48:
   include/asm-generic/fixmap.h: In function '__set_fixmap_offset':
   include/asm-generic/fixmap.h:78:2: error: implicit declaration of function '__set_fixmap'; did you mean 'set_fixmap'? [-Werror=implicit-function-declaration]
     __set_fixmap(idx, phys, flags);
     ^~~~~~~~~~~~
     set_fixmap
   In file included from arch/powerpc/mm/mem.c:48:0:
   arch/powerpc/include/asm/fixmap.h: At top level:
   arch/powerpc/include/asm/fixmap.h:77:20: error: conflicting types for '__set_fixmap' [-Werror]
    static inline void __set_fixmap(enum fixed_addresses idx,
                       ^~~~~~~~~~~~
>> arch/powerpc/include/asm/fixmap.h:77:20: error: static declaration of '__set_fixmap' follows non-static declaration
   In file included from arch/powerpc/include/asm/fixmap.h:75:0,
                    from arch/powerpc/mm/mem.c:48:
   include/asm-generic/fixmap.h:78:2: note: previous implicit declaration of '__set_fixmap' was here
     __set_fixmap(idx, phys, flags);
     ^~~~~~~~~~~~
   cc1: all warnings being treated as errors

vim +/__set_fixmap +77 arch/powerpc/include/asm/fixmap.h

2c419bdeca1d95 include/asm-powerpc/fixmap.h      Kumar Gala       2008-04-23  76  
4cfac2f9c7f116 arch/powerpc/include/asm/fixmap.h Christophe Leroy 2017-08-02 @77  static inline void __set_fixmap(enum fixed_addresses idx,
4cfac2f9c7f116 arch/powerpc/include/asm/fixmap.h Christophe Leroy 2017-08-02  78  				phys_addr_t phys, pgprot_t flags)
4cfac2f9c7f116 arch/powerpc/include/asm/fixmap.h Christophe Leroy 2017-08-02  79  {
c766ee72235d09 arch/powerpc/include/asm/fixmap.h Christophe Leroy 2018-10-09  80  	map_kernel_page(fix_to_virt(idx), phys, flags);
4cfac2f9c7f116 arch/powerpc/include/asm/fixmap.h Christophe Leroy 2017-08-02  81  }
4cfac2f9c7f116 arch/powerpc/include/asm/fixmap.h Christophe Leroy 2017-08-02  82  

:::::: The code at line 77 was first introduced by commit
:::::: 4cfac2f9c7f116af8516d0b3d0e7383189eca376 powerpc/mm: Simplify __set_fixmap()

:::::: TO: Christophe Leroy <christophe.leroy@c-s.fr>
:::::: CC: Michael Ellerman <mpe@ellerman.id.au>

---
0-DAY kernel test infrastructure                 Open Source Technology Center
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org Intel Corporation

[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 25378 bytes --]

Re: [PATCH] mm: fixmap: convert __set_fixmap_offset() to an inline function

[Masahiro Yamada]

Hi Andrew,

On Fri, Nov 8, 2019 at 9:42 PM Masahiro Yamada
<yamada.masahiro@socionext.com> wrote:
>
> I just stopped by the ugly variable name, ________addr.
> (8 underscores!)
>
> If this is just a matter of casting to (unsigned long), this variable
> is unneeded since you can do like this:
>
> ({                                                                      \
>         __set_fixmap(idx, phys, flags);                                 \
>         (unsigned long)(fix_to_virt(idx) + ((phys) & (PAGE_SIZE - 1))); \
> })
>
> However, I'd rather like to change it to an inline function since it
> is more readable, and the parameter types are clearer.
>
> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>


Unfortunately, this patch broke building ppc, mips, etc.
(Not all arch implement __set_fixmap)

Could you drop it from your tree?

Thanks.


-- 
Best Regards
Masahiro Yamada