linux_dsm_epyc7002/include/linux/sched/rt.h
Peter Zijlstra acd58620e4 sched/rtmutex: Refactor rt_mutex_setprio()
With the introduction of SCHED_DEADLINE the whole notion that priority
is a single number is gone, therefore the @prio argument to
rt_mutex_setprio() doesn't make sense anymore.

So rework the code to pass a pi_task instead.

Note this also fixes a problem with pi_top_task caching; previously we
would not set the pointer (call rt_mutex_update_top_task) if the
priority didn't change, this could lead to a stale pointer.

As for the XXX, I think its fine to use pi_task->prio, because if it
differs from waiter->prio, a PI chain update is immenent.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: juri.lelli@arm.com
Cc: bigeasy@linutronix.de
Cc: xlpang@redhat.com
Cc: rostedt@goodmis.org
Cc: mathieu.desnoyers@efficios.com
Cc: jdesfossez@efficios.com
Cc: bristot@redhat.com
Link: http://lkml.kernel.org/r/20170323150216.303827095@infradead.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-04-04 11:44:06 +02:00

56 lines
1.2 KiB
C

#ifndef _LINUX_SCHED_RT_H
#define _LINUX_SCHED_RT_H
#include <linux/sched.h>
struct task_struct;
static inline int rt_prio(int prio)
{
if (unlikely(prio < MAX_RT_PRIO))
return 1;
return 0;
}
static inline int rt_task(struct task_struct *p)
{
return rt_prio(p->prio);
}
#ifdef CONFIG_RT_MUTEXES
/*
* Must hold either p->pi_lock or task_rq(p)->lock.
*/
static inline struct task_struct *rt_mutex_get_top_task(struct task_struct *p)
{
return p->pi_top_task;
}
extern void rt_mutex_setprio(struct task_struct *p, struct task_struct *pi_task);
extern void rt_mutex_adjust_pi(struct task_struct *p);
static inline bool tsk_is_pi_blocked(struct task_struct *tsk)
{
return tsk->pi_blocked_on != NULL;
}
#else
static inline struct task_struct *rt_mutex_get_top_task(struct task_struct *task)
{
return NULL;
}
# define rt_mutex_adjust_pi(p) do { } while (0)
static inline bool tsk_is_pi_blocked(struct task_struct *tsk)
{
return false;
}
#endif
extern void normalize_rt_tasks(void);
/*
* default timeslice is 100 msecs (used only for SCHED_RR tasks).
* Timeslices get refilled after they expire.
*/
#define RR_TIMESLICE (100 * HZ / 1000)
#endif /* _LINUX_SCHED_RT_H */