forked from mirrors/linux
4865a27c66
Hi Linus,
Please pull patches for 6.10. This includes:
- topology_span_sane() optimization from Kyle Meyer;
- fns() rework from Kuan-Wei Chiu (used in
cpumask_local_spread() and other places); and
- headers cleanup from Andy.
This also adds a MAINTAINERS record for bitops API as it's unattended,
and I'd like to follow it closer.
Thanks,
Yury
-----BEGIN PGP SIGNATURE-----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=H6BQ
-----END PGP SIGNATURE-----
Merge tag 'bitmap-for-6.10v2' of https://github.com/norov/linux
Pull bitmap updates from Yury Norov:
- topology_span_sane() optimization from Kyle Meyer
- fns() rework from Kuan-Wei Chiu (used in cpumask_local_spread() and
other places)
- headers cleanup from Andy
- add a MAINTAINERS record for bitops API
* tag 'bitmap-for-6.10v2' of https://github.com/norov/linux:
usercopy: Don't use "proxy" headers
bitops: Move aligned_byte_mask() to wordpart.h
MAINTAINERS: add BITOPS API record
bitmap: relax find_nth_bit() limitation on return value
lib: make test_bitops compilable into the kernel image
bitops: Optimize fns() for improved performance
lib/test_bitops: Add benchmark test for fns()
Compiler Attributes: Add __always_used macro
sched/topology: Optimize topology_span_sane()
cpumask: Add for_each_cpu_from()
355 lines
9.3 KiB
C
355 lines
9.3 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
|
|
#ifndef _LINUX_BITOPS_H
|
|
#define _LINUX_BITOPS_H
|
|
|
|
#include <asm/types.h>
|
|
#include <linux/bits.h>
|
|
#include <linux/typecheck.h>
|
|
|
|
#include <uapi/linux/kernel.h>
|
|
|
|
#define BITS_PER_TYPE(type) (sizeof(type) * BITS_PER_BYTE)
|
|
#define BITS_TO_LONGS(nr) __KERNEL_DIV_ROUND_UP(nr, BITS_PER_TYPE(long))
|
|
#define BITS_TO_U64(nr) __KERNEL_DIV_ROUND_UP(nr, BITS_PER_TYPE(u64))
|
|
#define BITS_TO_U32(nr) __KERNEL_DIV_ROUND_UP(nr, BITS_PER_TYPE(u32))
|
|
#define BITS_TO_BYTES(nr) __KERNEL_DIV_ROUND_UP(nr, BITS_PER_TYPE(char))
|
|
|
|
#define BYTES_TO_BITS(nb) ((nb) * BITS_PER_BYTE)
|
|
|
|
extern unsigned int __sw_hweight8(unsigned int w);
|
|
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>
|
|
|
|
/*
|
|
* Many architecture-specific non-atomic bitops contain inline asm code and due
|
|
* to that the compiler can't optimize them to compile-time expressions or
|
|
* constants. In contrary, generic_*() helpers are defined in pure C and
|
|
* compilers optimize them just well.
|
|
* Therefore, to make `unsigned long foo = 0; __set_bit(BAR, &foo)` effectively
|
|
* equal to `unsigned long foo = BIT(BAR)`, pick the generic C alternative when
|
|
* the arguments can be resolved at compile time. That expression itself is a
|
|
* constant and doesn't bring any functional changes to the rest of cases.
|
|
* The casts to `uintptr_t` are needed to mitigate `-Waddress` warnings when
|
|
* passing a bitmap from .bss or .data (-> `!!addr` is always true).
|
|
*/
|
|
#define bitop(op, nr, addr) \
|
|
((__builtin_constant_p(nr) && \
|
|
__builtin_constant_p((uintptr_t)(addr) != (uintptr_t)NULL) && \
|
|
(uintptr_t)(addr) != (uintptr_t)NULL && \
|
|
__builtin_constant_p(*(const unsigned long *)(addr))) ? \
|
|
const##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)
|
|
#define test_bit_acquire(nr, addr) bitop(_test_bit_acquire, nr, addr)
|
|
|
|
/*
|
|
* Include this here because some architectures need generic_ffs/fls in
|
|
* scope
|
|
*/
|
|
#include <asm/bitops.h>
|
|
|
|
/* Check that the bitops prototypes are sane */
|
|
#define __check_bitop_pr(name) \
|
|
static_assert(__same_type(arch_##name, generic_##name) && \
|
|
__same_type(const_##name, generic_##name) && \
|
|
__same_type(_##name, generic_##name))
|
|
|
|
__check_bitop_pr(__set_bit);
|
|
__check_bitop_pr(__clear_bit);
|
|
__check_bitop_pr(__change_bit);
|
|
__check_bitop_pr(__test_and_set_bit);
|
|
__check_bitop_pr(__test_and_clear_bit);
|
|
__check_bitop_pr(__test_and_change_bit);
|
|
__check_bitop_pr(test_bit);
|
|
__check_bitop_pr(test_bit_acquire);
|
|
|
|
#undef __check_bitop_pr
|
|
|
|
static inline int get_bitmask_order(unsigned int count)
|
|
{
|
|
int order;
|
|
|
|
order = fls(count);
|
|
return order; /* We could be slightly more clever with -1 here... */
|
|
}
|
|
|
|
static __always_inline unsigned long hweight_long(unsigned long w)
|
|
{
|
|
return sizeof(w) == 4 ? hweight32(w) : hweight64((__u64)w);
|
|
}
|
|
|
|
/**
|
|
* rol64 - rotate a 64-bit value left
|
|
* @word: value to rotate
|
|
* @shift: bits to roll
|
|
*/
|
|
static inline __u64 rol64(__u64 word, unsigned int shift)
|
|
{
|
|
return (word << (shift & 63)) | (word >> ((-shift) & 63));
|
|
}
|
|
|
|
/**
|
|
* ror64 - rotate a 64-bit value right
|
|
* @word: value to rotate
|
|
* @shift: bits to roll
|
|
*/
|
|
static inline __u64 ror64(__u64 word, unsigned int shift)
|
|
{
|
|
return (word >> (shift & 63)) | (word << ((-shift) & 63));
|
|
}
|
|
|
|
/**
|
|
* rol32 - rotate a 32-bit value left
|
|
* @word: value to rotate
|
|
* @shift: bits to roll
|
|
*/
|
|
static inline __u32 rol32(__u32 word, unsigned int shift)
|
|
{
|
|
return (word << (shift & 31)) | (word >> ((-shift) & 31));
|
|
}
|
|
|
|
/**
|
|
* ror32 - rotate a 32-bit value right
|
|
* @word: value to rotate
|
|
* @shift: bits to roll
|
|
*/
|
|
static inline __u32 ror32(__u32 word, unsigned int shift)
|
|
{
|
|
return (word >> (shift & 31)) | (word << ((-shift) & 31));
|
|
}
|
|
|
|
/**
|
|
* rol16 - rotate a 16-bit value left
|
|
* @word: value to rotate
|
|
* @shift: bits to roll
|
|
*/
|
|
static inline __u16 rol16(__u16 word, unsigned int shift)
|
|
{
|
|
return (word << (shift & 15)) | (word >> ((-shift) & 15));
|
|
}
|
|
|
|
/**
|
|
* ror16 - rotate a 16-bit value right
|
|
* @word: value to rotate
|
|
* @shift: bits to roll
|
|
*/
|
|
static inline __u16 ror16(__u16 word, unsigned int shift)
|
|
{
|
|
return (word >> (shift & 15)) | (word << ((-shift) & 15));
|
|
}
|
|
|
|
/**
|
|
* rol8 - rotate an 8-bit value left
|
|
* @word: value to rotate
|
|
* @shift: bits to roll
|
|
*/
|
|
static inline __u8 rol8(__u8 word, unsigned int shift)
|
|
{
|
|
return (word << (shift & 7)) | (word >> ((-shift) & 7));
|
|
}
|
|
|
|
/**
|
|
* ror8 - rotate an 8-bit value right
|
|
* @word: value to rotate
|
|
* @shift: bits to roll
|
|
*/
|
|
static inline __u8 ror8(__u8 word, unsigned int shift)
|
|
{
|
|
return (word >> (shift & 7)) | (word << ((-shift) & 7));
|
|
}
|
|
|
|
/**
|
|
* sign_extend32 - sign extend a 32-bit value using specified bit as sign-bit
|
|
* @value: value to sign extend
|
|
* @index: 0 based bit index (0<=index<32) to sign bit
|
|
*
|
|
* This is safe to use for 16- and 8-bit types as well.
|
|
*/
|
|
static __always_inline __s32 sign_extend32(__u32 value, int index)
|
|
{
|
|
__u8 shift = 31 - index;
|
|
return (__s32)(value << shift) >> shift;
|
|
}
|
|
|
|
/**
|
|
* sign_extend64 - sign extend a 64-bit value using specified bit as sign-bit
|
|
* @value: value to sign extend
|
|
* @index: 0 based bit index (0<=index<64) to sign bit
|
|
*/
|
|
static __always_inline __s64 sign_extend64(__u64 value, int index)
|
|
{
|
|
__u8 shift = 63 - index;
|
|
return (__s64)(value << shift) >> shift;
|
|
}
|
|
|
|
static inline unsigned int fls_long(unsigned long l)
|
|
{
|
|
if (sizeof(l) == 4)
|
|
return fls(l);
|
|
return fls64(l);
|
|
}
|
|
|
|
static inline int get_count_order(unsigned int count)
|
|
{
|
|
if (count == 0)
|
|
return -1;
|
|
|
|
return fls(--count);
|
|
}
|
|
|
|
/**
|
|
* get_count_order_long - get order after rounding @l up to power of 2
|
|
* @l: parameter
|
|
*
|
|
* it is same as get_count_order() but with long type parameter
|
|
*/
|
|
static inline int get_count_order_long(unsigned long l)
|
|
{
|
|
if (l == 0UL)
|
|
return -1;
|
|
return (int)fls_long(--l);
|
|
}
|
|
|
|
/**
|
|
* __ffs64 - find first set bit in a 64 bit word
|
|
* @word: The 64 bit word
|
|
*
|
|
* On 64 bit arches this is a synonym for __ffs
|
|
* The result is not defined if no bits are set, so check that @word
|
|
* is non-zero before calling this.
|
|
*/
|
|
static inline unsigned int __ffs64(u64 word)
|
|
{
|
|
#if BITS_PER_LONG == 32
|
|
if (((u32)word) == 0UL)
|
|
return __ffs((u32)(word >> 32)) + 32;
|
|
#elif BITS_PER_LONG != 64
|
|
#error BITS_PER_LONG not 32 or 64
|
|
#endif
|
|
return __ffs((unsigned long)word);
|
|
}
|
|
|
|
/**
|
|
* fns - find N'th set bit in a word
|
|
* @word: The word to search
|
|
* @n: Bit to find
|
|
*/
|
|
static inline unsigned int fns(unsigned long word, unsigned int n)
|
|
{
|
|
while (word && n--)
|
|
word &= word - 1;
|
|
|
|
return word ? __ffs(word) : BITS_PER_LONG;
|
|
}
|
|
|
|
/**
|
|
* assign_bit - Assign value to a bit in memory
|
|
* @nr: the bit to set
|
|
* @addr: the address to start counting from
|
|
* @value: the value to assign
|
|
*/
|
|
#define assign_bit(nr, addr, value) \
|
|
((value) ? set_bit((nr), (addr)) : clear_bit((nr), (addr)))
|
|
|
|
#define __assign_bit(nr, addr, value) \
|
|
((value) ? __set_bit((nr), (addr)) : __clear_bit((nr), (addr)))
|
|
|
|
/**
|
|
* __ptr_set_bit - Set bit in a pointer's value
|
|
* @nr: the bit to set
|
|
* @addr: the address of the pointer variable
|
|
*
|
|
* Example:
|
|
* void *p = foo();
|
|
* __ptr_set_bit(bit, &p);
|
|
*/
|
|
#define __ptr_set_bit(nr, addr) \
|
|
({ \
|
|
typecheck_pointer(*(addr)); \
|
|
__set_bit(nr, (unsigned long *)(addr)); \
|
|
})
|
|
|
|
/**
|
|
* __ptr_clear_bit - Clear bit in a pointer's value
|
|
* @nr: the bit to clear
|
|
* @addr: the address of the pointer variable
|
|
*
|
|
* Example:
|
|
* void *p = foo();
|
|
* __ptr_clear_bit(bit, &p);
|
|
*/
|
|
#define __ptr_clear_bit(nr, addr) \
|
|
({ \
|
|
typecheck_pointer(*(addr)); \
|
|
__clear_bit(nr, (unsigned long *)(addr)); \
|
|
})
|
|
|
|
/**
|
|
* __ptr_test_bit - Test bit in a pointer's value
|
|
* @nr: the bit to test
|
|
* @addr: the address of the pointer variable
|
|
*
|
|
* Example:
|
|
* void *p = foo();
|
|
* if (__ptr_test_bit(bit, &p)) {
|
|
* ...
|
|
* } else {
|
|
* ...
|
|
* }
|
|
*/
|
|
#define __ptr_test_bit(nr, addr) \
|
|
({ \
|
|
typecheck_pointer(*(addr)); \
|
|
test_bit(nr, (unsigned long *)(addr)); \
|
|
})
|
|
|
|
#ifdef __KERNEL__
|
|
|
|
#ifndef set_mask_bits
|
|
#define set_mask_bits(ptr, mask, bits) \
|
|
({ \
|
|
const typeof(*(ptr)) mask__ = (mask), bits__ = (bits); \
|
|
typeof(*(ptr)) old__, new__; \
|
|
\
|
|
old__ = READ_ONCE(*(ptr)); \
|
|
do { \
|
|
new__ = (old__ & ~mask__) | bits__; \
|
|
} while (!try_cmpxchg(ptr, &old__, new__)); \
|
|
\
|
|
old__; \
|
|
})
|
|
#endif
|
|
|
|
#ifndef bit_clear_unless
|
|
#define bit_clear_unless(ptr, clear, test) \
|
|
({ \
|
|
const typeof(*(ptr)) clear__ = (clear), test__ = (test);\
|
|
typeof(*(ptr)) old__, new__; \
|
|
\
|
|
old__ = READ_ONCE(*(ptr)); \
|
|
do { \
|
|
if (old__ & test__) \
|
|
break; \
|
|
new__ = old__ & ~clear__; \
|
|
} while (!try_cmpxchg(ptr, &old__, new__)); \
|
|
\
|
|
!(old__ & test__); \
|
|
})
|
|
#endif
|
|
|
|
#endif /* __KERNEL__ */
|
|
#endif
|