Name
__test_and_clear_bit —
Clear a bit and return its old value
Synopsis
int __test_and_clear_bit ( | int nr, |
| | volatile unsigned long * addr); |
Arguments
nr
Bit to clear
addr
Address to count from
Description
This operation is non-atomic and can be reordered.
If two examples of this operation race, one can appear to succeed
but actually fail. You must protect multiple accesses with a lock.