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https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
synced 2026-07-23 22:38:20 -04:00
8a51b2e874
Fix the function prototypes to use the common parameter name 'addr'
instead of 'p' (common to arch-specific implementations of these
functions).
This avoids the kernel-doc warnings:
Warning: include/asm-generic/bitops/lock.h:19 function parameter 'p'
not described in 'arch_test_and_set_bit_lock'
Warning: include/asm-generic/bitops/lock.h:41 function parameter 'p'
not described in 'arch_clear_bit_unlock'
Warning: include/asm-generic/bitops/lock.h:59 function parameter 'p'
not described in 'arch___clear_bit_unlock'
Fixes: 84c6591103 ("locking/atomics, asm-generic/bitops/lock.h: Rewrite using atomic_fetch_*()")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Yury Norov <yury.norov@gmail.com>
83 lines
2.1 KiB
C
83 lines
2.1 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
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#ifndef _ASM_GENERIC_BITOPS_LOCK_H_
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#define _ASM_GENERIC_BITOPS_LOCK_H_
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#include <linux/atomic.h>
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#include <linux/compiler.h>
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#include <asm/barrier.h>
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/**
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* arch_test_and_set_bit_lock - Set a bit and return its old value, for lock
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* @nr: Bit to set
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* @addr: Address to count from
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*
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* This operation is atomic and provides acquire barrier semantics if
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* the returned value is 0.
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* It can be used to implement bit locks.
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*/
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static __always_inline int
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arch_test_and_set_bit_lock(unsigned int nr, volatile unsigned long *addr)
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{
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long old;
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unsigned long mask = BIT_MASK(nr);
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addr += BIT_WORD(nr);
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if (READ_ONCE(*addr) & mask)
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return 1;
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old = raw_atomic_long_fetch_or_acquire(mask, (atomic_long_t *)addr);
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return !!(old & mask);
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}
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/**
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* arch_clear_bit_unlock - Clear a bit in memory, for unlock
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* @nr: the bit to set
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* @addr: the address to start counting from
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*
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* This operation is atomic and provides release barrier semantics.
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*/
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static __always_inline void
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arch_clear_bit_unlock(unsigned int nr, volatile unsigned long *addr)
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{
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addr += BIT_WORD(nr);
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raw_atomic_long_fetch_andnot_release(BIT_MASK(nr), (atomic_long_t *)addr);
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}
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/**
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* arch___clear_bit_unlock - Clear a bit in memory, for unlock
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* @nr: the bit to set
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* @addr: the address to start counting from
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*
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* A weaker form of clear_bit_unlock() as used by __bit_lock_unlock(). If all
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* the bits in the word are protected by this lock some archs can use weaker
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* ops to safely unlock.
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*
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* See for example x86's implementation.
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*/
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static inline void
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arch___clear_bit_unlock(unsigned int nr, volatile unsigned long *addr)
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{
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unsigned long old;
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addr += BIT_WORD(nr);
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old = READ_ONCE(*addr);
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old &= ~BIT_MASK(nr);
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raw_atomic_long_set_release((atomic_long_t *)addr, old);
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}
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#ifndef arch_xor_unlock_is_negative_byte
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static inline bool arch_xor_unlock_is_negative_byte(unsigned long mask,
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volatile unsigned long *p)
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{
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long old;
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old = raw_atomic_long_fetch_xor_release(mask, (atomic_long_t *)p);
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return !!(old & BIT(7));
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}
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#endif
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#include <asm-generic/bitops/instrumented-lock.h>
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#endif /* _ASM_GENERIC_BITOPS_LOCK_H_ */
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