static int receiver_wake_function(wait_queue_t *wait, unsigned mode, int sync,
void *key)
{
unsigned long bits = (unsigned long)key;
if (bits && !(bits & (POLLIN | POLLERR)))
return 0;
return autoremove_wake_function(wait, mode, sync, key);
}
static int receiver_wake_function(wait_queue_entry_t *wait, unsigned int mode, int sync,
void *key)
{
/*
* Avoid a wakeup if event not interesting for us
*/
if (key && !(key_to_poll(key) & (EPOLLIN | EPOLLERR)))
return 0;
return autoremove_wake_function(wait, mode, sync, key);
}
static int receiver_wake_function(wait_queue_t *wait, unsigned mode, int sync,
void *key)
{
unsigned long bits = (unsigned long)key;
/*
* Avoid a wakeup if event not interesting for us
*/
if (bits && !(bits & (POLLIN | POLLERR)))
return 0;
return autoremove_wake_function(wait, mode, sync, key);
}
int wake_bit_function(wait_queue_t *wait, unsigned mode, int sync, void *arg)
{
struct wait_bit_key *key = arg;
struct wait_bit_queue *wait_bit
= container_of(wait, struct wait_bit_queue, wait);
if (wait_bit->key.flags != key->flags ||
wait_bit->key.bit_nr != key->bit_nr ||
test_bit(key->bit_nr, key->flags))
return 0;
else
return autoremove_wake_function(wait, mode, sync, key);
}
static int wake_atomic_t_function(wait_queue_t *wait, unsigned mode, int sync,
void *arg)
{
struct wait_bit_key *key = arg;
struct wait_bit_queue *wait_bit
= container_of(wait, struct wait_bit_queue, wait);
atomic_t *val = key->flags;
if (wait_bit->key.flags != key->flags ||
wait_bit->key.bit_nr != key->bit_nr ||
atomic_read(val) != 0)
return 0;
return autoremove_wake_function(wait, mode, sync, key);
}
/*
* the autoremove wake function will return 0 if it tried to wake up
* a process that was already awake, which means that process won't
* count as an exclusive wakeup. The waitq code will continue waking
* procs until it finds one that was actually sleeping.
*
* For btrfs, this isn't quite what we want. We want a single proc
* to be notified that the lock is ready for taking. If that proc
* already happen to be awake, great, it will loop around and try for
* the lock.
*
* So, btrfs_wake_function always returns 1, even when the proc that we
* tried to wake up was already awake.
*/
static int btrfs_wake_function(wait_queue_t *wait, unsigned mode,
int sync, void *key)
{
autoremove_wake_function(wait, mode, sync, key);
return 1;
}