__set_bit(9) centos man page | unix.com

__SET_BIT(9)						     Basic C Library Functions						      __SET_BIT(9)

NAME
       __set_bit - Set a bit in memory

SYNOPSIS
       void __set_bit(int nr, volatile unsigned long * addr);

ARGUMENTS
       nr
	   the bit to set

       addr
	   the address to start counting from

DESCRIPTION
       Unlike set_bit, this function is non-atomic and may be reordered. If it's called on the same region of memory simultaneously, the effect
       may be that only one operation succeeds.

COPYRIGHT
Kernel Hackers Manual 3.10					     June 2014							      __SET_BIT(9)