futex: Allow for compiling out PI support

This makes it possible to preserve basic futex support and compile out the
PI support when RT mutexes are not available.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Darren Hart <dvhart@infradead.org>
Link: http://lkml.kernel.org/r/alpine.LFD.2.20.1708010024190.5981@knanqh.ubzr
This commit is contained in:
Nicolas Pitre 2017-08-01 00:31:32 -04:00 committed by Thomas Gleixner
parent f06e8c584f
commit bc2eecd7ec
4 changed files with 63 additions and 2 deletions

View file

@ -40,6 +40,9 @@ struct rt_mutex_waiter {
/*
* Various helpers to access the waiters-tree:
*/
#ifdef CONFIG_RT_MUTEXES
static inline int rt_mutex_has_waiters(struct rt_mutex *lock)
{
return !RB_EMPTY_ROOT(&lock->waiters);
@ -69,6 +72,32 @@ task_top_pi_waiter(struct task_struct *p)
pi_tree_entry);
}
#else
static inline int rt_mutex_has_waiters(struct rt_mutex *lock)
{
return false;
}
static inline struct rt_mutex_waiter *
rt_mutex_top_waiter(struct rt_mutex *lock)
{
return NULL;
}
static inline int task_has_pi_waiters(struct task_struct *p)
{
return false;
}
static inline struct rt_mutex_waiter *
task_top_pi_waiter(struct task_struct *p)
{
return NULL;
}
#endif
/*
* lock->owner state tracking:
*/