Re: [PATCH v3 5/7] bitops: wrap non-atomic bitops with a transparent macro

Andy Shevchenko
2022-06-20T10:09:01Z

On Fri, Jun 17, 2022 at 04:40:29PM +0200, Alexander Lobakin wrote:
> In preparation for altering the non-atomic bitops with a macro, wrap
> them in a transparent definition. This requires prepending one more
> '_' to their names in order to be able to do that seamlessly. It is
> a simple change, given that all the non-prefixed definitions are now
> in asm-generic.
> sparc32 already has several triple-underscored functions, so I had
> to rename them ('___' -> 'sp32_').

Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

> Signed-off-by: Alexander Lobakin <alexandr.lobakin@intel.com>
> ---
> arch/sparc/include/asm/bitops_32.h | 18 ++++++------
> arch/sparc/lib/atomic32.c | 12 ++++----
> .../bitops/instrumented-non-atomic.h | 28 +++++++++----------
> .../bitops/non-instrumented-non-atomic.h | 14 +++++-----
> include/linux/bitops.h | 18 +++++++++++-
> tools/include/asm-generic/bitops/non-atomic.h | 24 ++++++++--------
> tools/include/linux/bitops.h | 16 +++++++++++
> 7 files changed, 81 insertions(+), 49 deletions(-)
>
> diff --git a/arch/sparc/include/asm/bitops_32.h b/arch/sparc/include/asm/bitops_32.h
> index 889afa9f990f..3448c191b484 100644
> --- a/arch/sparc/include/asm/bitops_32.h
> +++ b/arch/sparc/include/asm/bitops_32.h
> @@ -19,9 +19,9 @@
> #error only <linux/bitops.h> can be included directly
> #endif
>
> -unsigned long ___set_bit(unsigned long *addr, unsigned long mask);
> -unsigned long ___clear_bit(unsigned long *addr, unsigned long mask);
> -unsigned long ___change_bit(unsigned long *addr, unsigned long mask);
> +unsigned long sp32___set_bit(unsigned long *addr, unsigned long mask);
> +unsigned long sp32___clear_bit(unsigned long *addr, unsigned long mask);
> +unsigned long sp32___change_bit(unsigned long *addr, unsigned long mask);
>
> /*
> * Set bit 'nr' in 32-bit quantity at address 'addr' where bit '0'
> @@ -36,7 +36,7 @@ static inline int test_and_set_bit(unsigned long nr, volatile unsigned long *add
> ADDR = ((unsigned long *) addr) + (nr >> 5);
> mask = 1 << (nr & 31);
>
> - return ___set_bit(ADDR, mask) != 0;
> + return sp32___set_bit(ADDR, mask) != 0;
> }
>
> static inline void set_bit(unsigned long nr, volatile unsigned long *addr)
> @@ -46,7 +46,7 @@ static inline void set_bit(unsigned long nr, volatile unsigned long *addr)
> ADDR = ((unsigned long *) addr) + (nr >> 5);
> mask = 1 << (nr & 31);
>
> - (void) ___set_bit(ADDR, mask);
> + (void) sp32___set_bit(ADDR, mask);
> }
>
> static inline int test_and_clear_bit(unsigned long nr, volatile unsigned long *addr)
> @@ -56,7 +56,7 @@ static inline int test_and_clear_bit(unsigned long nr, volatile unsigned long *a
> ADDR = ((unsigned long *) addr) + (nr >> 5);
> mask = 1 << (nr & 31);
>
> - return ___clear_bit(ADDR, mask) != 0;
> + return sp32___clear_bit(ADDR, mask) != 0;
> }
>
> static inline void clear_bit(unsigned long nr, volatile unsigned long *addr)
> @@ -66,7 +66,7 @@ static inline void clear_bit(unsigned long nr, volatile unsigned long *addr)
> ADDR = ((unsigned long *) addr) + (nr >> 5);
> mask = 1 << (nr & 31);
>
> - (void) ___clear_bit(ADDR, mask);
> + (void) sp32___clear_bit(ADDR, mask);
> }
>
> static inline int test_and_change_bit(unsigned long nr, volatile unsigned long *addr)
> @@ -76,7 +76,7 @@ static inline int test_and_change_bit(unsigned long nr, volatile unsigned long *
> ADDR = ((unsigned long *) addr) + (nr >> 5);
> mask = 1 << (nr & 31);
>
> - return ___change_bit(ADDR, mask) != 0;
> + return sp32___change_bit(ADDR, mask) != 0;
> }
>
> static inline void change_bit(unsigned long nr, volatile unsigned long *addr)
> @@ -86,7 +86,7 @@ static inline void change_bit(unsigned long nr, volatile unsigned long *addr)
> ADDR = ((unsigned long *) addr) + (nr >> 5);
> mask = 1 << (nr & 31);
>
> - (void) ___change_bit(ADDR, mask);
> + (void) sp32___change_bit(ADDR, mask);
> }
>
> #include <asm-generic/bitops/non-atomic.h>
> diff --git a/arch/sparc/lib/atomic32.c b/arch/sparc/lib/atomic32.c
> index 8b81d0f00c97..cf80d1ae352b 100644
> --- a/arch/sparc/lib/atomic32.c
> +++ b/arch/sparc/lib/atomic32.c
> @@ -120,7 +120,7 @@ void arch_atomic_set(atomic_t *v, int i)
> }
> EXPORT_SYMBOL(arch_atomic_set);
>
> -unsigned long ___set_bit(unsigned long *addr, unsigned long mask)
> +unsigned long sp32___set_bit(unsigned long *addr, unsigned long mask)
> {
> unsigned long old, flags;
>
> @@ -131,9 +131,9 @@ unsigned long ___set_bit(unsigned long *addr, unsigned long mask)
>
> return old & mask;
> }
> -EXPORT_SYMBOL(___set_bit);
> +EXPORT_SYMBOL(sp32___set_bit);
>
> -unsigned long ___clear_bit(unsigned long *addr, unsigned long mask)
> +unsigned long sp32___clear_bit(unsigned long *addr, unsigned long mask)
> {
> unsigned long old, flags;
>
> @@ -144,9 +144,9 @@ unsigned long ___clear_bit(unsigned long *addr, unsigned long mask)
>
> return old & mask;
> }
> -EXPORT_SYMBOL(___clear_bit);
> +EXPORT_SYMBOL(sp32___clear_bit);
>
> -unsigned long ___change_bit(unsigned long *addr, unsigned long mask)
> +unsigned long sp32___change_bit(unsigned long *addr, unsigned long mask)
> {
> unsigned long old, flags;
>
> @@ -157,7 +157,7 @@ unsigned long ___change_bit(unsigned long *addr, unsigned long mask)
>
> return old & mask;
> }
> -EXPORT_SYMBOL(___change_bit);
> +EXPORT_SYMBOL(sp32___change_bit);
>
> unsigned long __cmpxchg_u32(volatile u32 *ptr, u32 old, u32 new)
> {
> diff --git a/include/asm-generic/bitops/instrumented-non-atomic.h b/include/asm-generic/bitops/instrumented-non-atomic.h
> index b019f77ef21c..988a3bbfba34 100644
> --- a/include/asm-generic/bitops/instrumented-non-atomic.h
> +++ b/include/asm-generic/bitops/instrumented-non-atomic.h
> @@ -14,7 +14,7 @@
> #include <linux/instrumented.h>
>
> /**
> - * __set_bit - Set a bit in memory
> + * ___set_bit - Set a bit in memory
> * @nr: the bit to set
> * @addr: the address to start counting from
> *
> @@ -23,14 +23,14 @@
> * succeeds.
> */
> static __always_inline void
> -__set_bit(unsigned long nr, volatile unsigned long *addr)
> +___set_bit(unsigned long nr, volatile unsigned long *addr)
> {
> instrument_write(addr + BIT_WORD(nr), sizeof(long));
> arch___set_bit(nr, addr);
> }
>
> /**
> - * __clear_bit - Clears a bit in memory
> + * ___clear_bit - Clears a bit in memory
> * @nr: the bit to clear
> * @addr: the address to start counting from
> *
> @@ -39,14 +39,14 @@ __set_bit(unsigned long nr, volatile unsigned long *addr)
> * succeeds.
> */
> static __always_inline void
> -__clear_bit(unsigned long nr, volatile unsigned long *addr)
> +___clear_bit(unsigned long nr, volatile unsigned long *addr)
> {
> instrument_write(addr + BIT_WORD(nr), sizeof(long));
> arch___clear_bit(nr, addr);
> }
>
> /**
> - * __change_bit - Toggle a bit in memory
> + * ___change_bit - Toggle a bit in memory
> * @nr: the bit to change
> * @addr: the address to start counting from
> *
> @@ -55,7 +55,7 @@ __clear_bit(unsigned long nr, volatile unsigned long *addr)
> * succeeds.
> */
> static __always_inline void
> -__change_bit(unsigned long nr, volatile unsigned long *addr)
> +___change_bit(unsigned long nr, volatile unsigned long *addr)
> {
> instrument_write(addr + BIT_WORD(nr), sizeof(long));
> arch___change_bit(nr, addr);
> @@ -86,7 +86,7 @@ static __always_inline void __instrument_read_write_bitop(long nr, volatile unsi
> }
>
> /**
> - * __test_and_set_bit - Set a bit and return its old value
> + * ___test_and_set_bit - Set a bit and return its old value
> * @nr: Bit to set
> * @addr: Address to count from
> *
> @@ -94,14 +94,14 @@ static __always_inline void __instrument_read_write_bitop(long nr, volatile unsi
> * can appear to succeed but actually fail.
> */
> static __always_inline bool
> -__test_and_set_bit(unsigned long nr, volatile unsigned long *addr)
> +___test_and_set_bit(unsigned long nr, volatile unsigned long *addr)
> {
> __instrument_read_write_bitop(nr, addr);
> return arch___test_and_set_bit(nr, addr);
> }
>
> /**
> - * __test_and_clear_bit - Clear a bit and return its old value
> + * ___test_and_clear_bit - Clear a bit and return its old value
> * @nr: Bit to clear
> * @addr: Address to count from
> *
> @@ -109,14 +109,14 @@ __test_and_set_bit(unsigned long nr, volatile unsigned long *addr)
> * can appear to succeed but actually fail.
> */
> static __always_inline bool
> -__test_and_clear_bit(unsigned long nr, volatile unsigned long *addr)
> +___test_and_clear_bit(unsigned long nr, volatile unsigned long *addr)
> {
> __instrument_read_write_bitop(nr, addr);
> return arch___test_and_clear_bit(nr, addr);
> }
>
> /**
> - * __test_and_change_bit - Change a bit and return its old value
> + * ___test_and_change_bit - Change a bit and return its old value
> * @nr: Bit to change
> * @addr: Address to count from
> *
> @@ -124,19 +124,19 @@ __test_and_clear_bit(unsigned long nr, volatile unsigned long *addr)
> * can appear to succeed but actually fail.
> */
> static __always_inline bool
> -__test_and_change_bit(unsigned long nr, volatile unsigned long *addr)
> +___test_and_change_bit(unsigned long nr, volatile unsigned long *addr)
> {
> __instrument_read_write_bitop(nr, addr);
> return arch___test_and_change_bit(nr, addr);
> }
>
> /**
> - * test_bit - Determine whether a bit is set
> + * _test_bit - Determine whether a bit is set
> * @nr: bit number to test
> * @addr: Address to start counting from
> */
> static __always_inline bool
> -test_bit(unsigned long nr, const volatile unsigned long *addr)
> +_test_bit(unsigned long nr, const volatile unsigned long *addr)
> {
> instrument_atomic_read(addr + BIT_WORD(nr), sizeof(long));
> return arch_test_bit(nr, addr);
> diff --git a/include/asm-generic/bitops/non-instrumented-non-atomic.h b/include/asm-generic/bitops/non-instrumented-non-atomic.h
> index e0fd7bf72a56..bdb9b1ffaee9 100644
> --- a/include/asm-generic/bitops/non-instrumented-non-atomic.h
> +++ b/include/asm-generic/bitops/non-instrumented-non-atomic.h
> @@ -3,14 +3,14 @@
> #ifndef __ASM_GENERIC_BITOPS_NON_INSTRUMENTED_NON_ATOMIC_H
> #define __ASM_GENERIC_BITOPS_NON_INSTRUMENTED_NON_ATOMIC_H
>
> -#define __set_bit arch___set_bit
> -#define __clear_bit arch___clear_bit
> -#define __change_bit arch___change_bit
> +#define ___set_bit arch___set_bit
> +#define ___clear_bit arch___clear_bit
> +#define ___change_bit arch___change_bit
>
> -#define __test_and_set_bit arch___test_and_set_bit
> -#define __test_and_clear_bit arch___test_and_clear_bit
> -#define __test_and_change_bit arch___test_and_change_bit
> +#define ___test_and_set_bit arch___test_and_set_bit
> +#define ___test_and_clear_bit arch___test_and_clear_bit
> +#define ___test_and_change_bit arch___test_and_change_bit
>
> -#define test_bit arch_test_bit
> +#define _test_bit arch_test_bit
>
> #endif /* __ASM_GENERIC_BITOPS_NON_INSTRUMENTED_NON_ATOMIC_H */
> diff --git a/include/linux/bitops.h b/include/linux/bitops.h
> index d393297287d5..3c3afbae1533 100644
> --- a/include/linux/bitops.h
> +++ b/include/linux/bitops.h
> @@ -26,8 +26,24 @@ extern unsigned int __sw_hweight16(unsigned int w);
> extern unsigned int __sw_hweight32(unsigned int w);
> extern unsigned long __sw_hweight64(__u64 w);
>
> +/*
> + * Defined here because those may be needed by architecture-specific static
> + * inlines.
> + */
> +
> #include <asm-generic/bitops/generic-non-atomic.h>
>
> +#define bitop(op, nr, addr) \
> + op(nr, addr)
> +
> +#define __set_bit(nr, addr) bitop(___set_bit, nr, addr)
> +#define __clear_bit(nr, addr) bitop(___clear_bit, nr, addr)
> +#define __change_bit(nr, addr) bitop(___change_bit, nr, addr)
> +#define __test_and_set_bit(nr, addr) bitop(___test_and_set_bit, nr, addr)
> +#define __test_and_clear_bit(nr, addr) bitop(___test_and_clear_bit, nr, addr)
> +#define __test_and_change_bit(nr, addr) bitop(___test_and_change_bit, nr, addr)
> +#define test_bit(nr, addr) bitop(_test_bit, nr, addr)
> +
> /*
> * Include this here because some architectures need generic_ffs/fls in
> * scope
> @@ -38,7 +54,7 @@ extern unsigned long __sw_hweight64(__u64 w);
> #define __check_bitop_pr(name) \
> static_assert(__same_type(arch_##name, generic_##name) && \
> __same_type(const_##name, generic_##name) && \
> - __same_type(name, generic_##name))
> + __same_type(_##name, generic_##name))
>
> __check_bitop_pr(__set_bit);
> __check_bitop_pr(__clear_bit);
> diff --git a/tools/include/asm-generic/bitops/non-atomic.h b/tools/include/asm-generic/bitops/non-atomic.h
> index e5e78e42e57b..0c472a833408 100644
> --- a/tools/include/asm-generic/bitops/non-atomic.h
> +++ b/tools/include/asm-generic/bitops/non-atomic.h
> @@ -5,7 +5,7 @@
> #include <linux/bits.h>
>
> /**
> - * __set_bit - Set a bit in memory
> + * ___set_bit - Set a bit in memory
> * @nr: the bit to set
> * @addr: the address to start counting from
> *
> @@ -14,7 +14,7 @@
> * may be that only one operation succeeds.
> */
> static __always_inline void
> -__set_bit(unsigned long nr, volatile unsigned long *addr)
> +___set_bit(unsigned long nr, volatile unsigned long *addr)
> {
> unsigned long mask = BIT_MASK(nr);
> unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
> @@ -23,7 +23,7 @@ __set_bit(unsigned long nr, volatile unsigned long *addr)
> }
>
> static __always_inline void
> -__clear_bit(unsigned long nr, volatile unsigned long *addr)
> +___clear_bit(unsigned long nr, volatile unsigned long *addr)
> {
> unsigned long mask = BIT_MASK(nr);
> unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
> @@ -32,7 +32,7 @@ __clear_bit(unsigned long nr, volatile unsigned long *addr)
> }
>
> /**
> - * __change_bit - Toggle a bit in memory
> + * ___change_bit - Toggle a bit in memory
> * @nr: the bit to change
> * @addr: the address to start counting from
> *
> @@ -41,7 +41,7 @@ __clear_bit(unsigned long nr, volatile unsigned long *addr)
> * may be that only one operation succeeds.
> */
> static __always_inline void
> -__change_bit(unsigned long nr, volatile unsigned long *addr)
> +___change_bit(unsigned long nr, volatile unsigned long *addr)
> {
> unsigned long mask = BIT_MASK(nr);
> unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
> @@ -50,7 +50,7 @@ __change_bit(unsigned long nr, volatile unsigned long *addr)
> }
>
> /**
> - * __test_and_set_bit - Set a bit and return its old value
> + * ___test_and_set_bit - Set a bit and return its old value
> * @nr: Bit to set
> * @addr: Address to count from
> *
> @@ -59,7 +59,7 @@ __change_bit(unsigned long nr, volatile unsigned long *addr)
> * but actually fail. You must protect multiple accesses with a lock.
> */
> static __always_inline bool
> -__test_and_set_bit(unsigned long nr, volatile unsigned long *addr)
> +___test_and_set_bit(unsigned long nr, volatile unsigned long *addr)
> {
> unsigned long mask = BIT_MASK(nr);
> unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
> @@ -70,7 +70,7 @@ __test_and_set_bit(unsigned long nr, volatile unsigned long *addr)
> }
>
> /**
> - * __test_and_clear_bit - Clear a bit and return its old value
> + * ___test_and_clear_bit - Clear a bit and return its old value
> * @nr: Bit to clear
> * @addr: Address to count from
> *
> @@ -79,7 +79,7 @@ __test_and_set_bit(unsigned long nr, volatile unsigned long *addr)
> * but actually fail. You must protect multiple accesses with a lock.
> */
> static __always_inline bool
> -__test_and_clear_bit(unsigned long nr, volatile unsigned long *addr)
> +___test_and_clear_bit(unsigned long nr, volatile unsigned long *addr)
> {
> unsigned long mask = BIT_MASK(nr);
> unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
> @@ -91,7 +91,7 @@ __test_and_clear_bit(unsigned long nr, volatile unsigned long *addr)
>
> /* WARNING: non atomic and it can be reordered! */
> static __always_inline bool
> -__test_and_change_bit(unsigned long nr, volatile unsigned long *addr)
> +___test_and_change_bit(unsigned long nr, volatile unsigned long *addr)
> {
> unsigned long mask = BIT_MASK(nr);
> unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
> @@ -102,12 +102,12 @@ __test_and_change_bit(unsigned long nr, volatile unsigned long *addr)
> }
>
> /**
> - * test_bit - Determine whether a bit is set
> + * _test_bit - Determine whether a bit is set
> * @nr: bit number to test
> * @addr: Address to start counting from
> */
> static __always_inline bool
> -test_bit(unsigned long nr, const volatile unsigned long *addr)
> +_test_bit(unsigned long nr, const volatile unsigned long *addr)
> {
> return 1UL & (addr[BIT_WORD(nr)] >> (nr & (BITS_PER_LONG-1)));
> }
> diff --git a/tools/include/linux/bitops.h b/tools/include/linux/bitops.h
> index 5fca38fe1ba8..f18683b95ea6 100644
> --- a/tools/include/linux/bitops.h
> +++ b/tools/include/linux/bitops.h
> @@ -25,6 +25,22 @@ extern unsigned int __sw_hweight16(unsigned int w);
> extern unsigned int __sw_hweight32(unsigned int w);
> extern unsigned long __sw_hweight64(__u64 w);
>
> +/*
> + * Defined here because those may be needed by architecture-specific static
> + * inlines.
> + */
> +
> +#define bitop(op, nr, addr) \
> + op(nr, addr)
> +
> +#define __set_bit(nr, addr) bitop(___set_bit, nr, addr)
> +#define __clear_bit(nr, addr) bitop(___clear_bit, nr, addr)
> +#define __change_bit(nr, addr) bitop(___change_bit, nr, addr)
> +#define __test_and_set_bit(nr, addr) bitop(___test_and_set_bit, nr, addr)
> +#define __test_and_clear_bit(nr, addr) bitop(___test_and_clear_bit, nr, addr)
> +#define __test_and_change_bit(nr, addr) bitop(___test_and_change_bit, nr, addr)
> +#define test_bit(nr, addr) bitop(_test_bit, nr, addr)
> +
> /*
> * Include this here because some architectures need generic_ffs/fls in
> * scope
> --
> 2.36.1
>

--
With Best Regards,
Andy Shevchenko