wait_on_bit - wait for a bit to be cleared
int wait_on_bit(unsigned long * word, int bit, unsigned mode);
There is a standard hashed waitqueue table for generic use. This is the part of the hashtable's accessor API that waits on a bit. For instance, if one were to have waiters on a bitflag, one would call wait_on_bit in threads waiting for the bit to clear. One uses wait_on_bit where one is waiting for the bit to clear, but has no intention of setting it. Returned value will be zero if the bit was cleared, or non-zero if the process received a signal and the mode permitted wakeup on that signal.
|January 2017||Kernel Hackers Manual 4.8.|