tty/ldsem: Remove unused ldsem_down_write_trylock

ldsem_down_write_trylock() was added in 2013 by
commit 4898e640caf0 ("tty: Add timed, writer-prioritized rw semaphore")
but hasn't been used.

Remove it.

Signed-off-by: Dr. David Alan Gilbert <linux@treblig.org>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20250122012559.441006-1-linux@treblig.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Dr. David Alan Gilbert 2025-01-22 01:25:59 +00:00 committed by Greg Kroah-Hartman
parent f0c8814c1c
commit 42e128c9d5
2 changed files with 0 additions and 18 deletions

View File

@ -366,23 +366,6 @@ int __sched ldsem_down_write(struct ld_semaphore *sem, long timeout)
return __ldsem_down_write_nested(sem, 0, timeout);
}
/*
* trylock for writing -- returns 1 if successful, 0 if contention
*/
int ldsem_down_write_trylock(struct ld_semaphore *sem)
{
long count = atomic_long_read(&sem->count);
while ((count & LDSEM_ACTIVE_MASK) == 0) {
if (atomic_long_try_cmpxchg(&sem->count, &count, count + LDSEM_WRITE_BIAS)) {
rwsem_acquire(&sem->dep_map, 0, 1, _RET_IP_);
lock_acquired(&sem->dep_map, _RET_IP_);
return 1;
}
}
return 0;
}
/*
* release a read lock
*/

View File

@ -39,7 +39,6 @@ do { \
int ldsem_down_read(struct ld_semaphore *sem, long timeout);
int ldsem_down_read_trylock(struct ld_semaphore *sem);
int ldsem_down_write(struct ld_semaphore *sem, long timeout);
int ldsem_down_write_trylock(struct ld_semaphore *sem);
void ldsem_up_read(struct ld_semaphore *sem);
void ldsem_up_write(struct ld_semaphore *sem);