From bdab18633a302c82b5e5d5dbc4e38b0baf9c0837 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sun, 20 Sep 2026 08:15:23 -0700 Subject: Merge tag 'locking-urgent-2026-09-20' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull futex fix from Ingo Molnar: - Also allocate a default private futex hash on vfork() as well, to avoid races with (private) futex waiters (Peter Zijlstra) * tag 'locking-urgent-2026-09-20' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: futex: Also allocate private hash on vfork() --- include/asm-generic/bitops/atomic.h | 70 +++++++++++++++++++++++++++++++++++++ 1 file changed, 70 insertions(+) create mode 100644 include/asm-generic/bitops/atomic.h (limited to 'include/asm-generic/bitops/atomic.h') diff --git a/include/asm-generic/bitops/atomic.h b/include/asm-generic/bitops/atomic.h new file mode 100644 index 000000000..e076e079f --- /dev/null +++ b/include/asm-generic/bitops/atomic.h @@ -0,0 +1,70 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _ASM_GENERIC_BITOPS_ATOMIC_H_ +#define _ASM_GENERIC_BITOPS_ATOMIC_H_ + +#include +#include +#include + +/* + * Implementation of atomic bitops using atomic-fetch ops. + * See Documentation/atomic_bitops.txt for details. + */ + +static __always_inline void +arch_set_bit(unsigned int nr, volatile unsigned long *p) +{ + p += BIT_WORD(nr); + raw_atomic_long_or(BIT_MASK(nr), (atomic_long_t *)p); +} + +static __always_inline void +arch_clear_bit(unsigned int nr, volatile unsigned long *p) +{ + p += BIT_WORD(nr); + raw_atomic_long_andnot(BIT_MASK(nr), (atomic_long_t *)p); +} + +static __always_inline void +arch_change_bit(unsigned int nr, volatile unsigned long *p) +{ + p += BIT_WORD(nr); + raw_atomic_long_xor(BIT_MASK(nr), (atomic_long_t *)p); +} + +static __always_inline int +arch_test_and_set_bit(unsigned int nr, volatile unsigned long *p) +{ + long old; + unsigned long mask = BIT_MASK(nr); + + p += BIT_WORD(nr); + old = raw_atomic_long_fetch_or(mask, (atomic_long_t *)p); + return !!(old & mask); +} + +static __always_inline int +arch_test_and_clear_bit(unsigned int nr, volatile unsigned long *p) +{ + long old; + unsigned long mask = BIT_MASK(nr); + + p += BIT_WORD(nr); + old = raw_atomic_long_fetch_andnot(mask, (atomic_long_t *)p); + return !!(old & mask); +} + +static __always_inline int +arch_test_and_change_bit(unsigned int nr, volatile unsigned long *p) +{ + long old; + unsigned long mask = BIT_MASK(nr); + + p += BIT_WORD(nr); + old = raw_atomic_long_fetch_xor(mask, (atomic_long_t *)p); + return !!(old & mask); +} + +#include + +#endif /* _ASM_GENERIC_BITOPS_ATOMIC_H */ -- cgit v1.3.1