| Message ID | 20230915183707.2707298-13-willy@infradead.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Add folio_end_read | expand |
diff --git a/arch/riscv/include/asm/bitops.h b/arch/riscv/include/asm/bitops.h index 3540b690944b..15e3044298a2 100644 --- a/arch/riscv/include/asm/bitops.h +++ b/arch/riscv/include/asm/bitops.h @@ -191,6 +191,19 @@ static inline void __clear_bit_unlock( clear_bit_unlock(nr, addr); } +static inline bool xor_unlock_is_negative_byte(unsigned long mask, + volatile unsigned long *addr) +{ + unsigned long res; + __asm__ __volatile__ ( + __AMO(xor) ".rl %0, %2, %1" + : "=r" (res), "+A" (*addr) + : "r" (__NOP(mask)) + : "memory"); + return (res & BIT(7)) != 0; +} +#define xor_unlock_is_negative_byte xor_unlock_is_negative_byte + #undef __test_and_op_bit #undef __op_bit #undef __NOP
Inspired by the riscv clear_bit_unlock(), this will surely be more efficient than the generic one defined in filemap.c. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> --- arch/riscv/include/asm/bitops.h | 13 +++++++++++++ 1 file changed, 13 insertions(+)