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sched/core: Remove ifdeffery for saved_state

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In preparation for freezer to also use saved_state, remove the
CONFIG_PREEMPT_RT compilation guard around saved_state.

On the arm64 platform I tested which did not have CONFIG_PREEMPT_RT,
there was no statistically significant deviation by applying this patch.

Test methodology:

perf bench sched message -g 40 -l 40

Signed-off-by: Elliot Berman <quic_eberman@quicinc.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Elliot Berman 2023-09-08 15:49:15 -07:00 committed by Ingo Molnar
parent 4ff34ad3d3
commit fbaa6a181a
2 changed files with 2 additions and 8 deletions
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2
include/linux/sched.h
View file

@ -750,10 +750,8 @@ struct task_struct {
#endif
unsigned int __state;
#ifdef CONFIG_PREEMPT_RT
/* saved state for "spinlock sleepers" */
unsigned int saved_state;
#endif
/*
* This begins the randomizable portion of task_struct. Only

8
kernel/sched/core.c
View file

@ -2232,23 +2232,20 @@ int __task_state_match(struct task_struct *p, unsigned int state)
if (READ_ONCE(p->__state) & state)
return 1;
#ifdef CONFIG_PREEMPT_RT
if (READ_ONCE(p->saved_state) & state)
return -1;
#endif
return 0;
}
static __always_inline
int task_state_match(struct task_struct *p, unsigned int state)
{
#ifdef CONFIG_PREEMPT_RT
/*
* Serialize against current_save_and_set_rtlock_wait_state() and
* current_restore_rtlock_saved_state().
*/
guard(raw_spinlock_irq)(&p->pi_lock);
#endif
return __task_state_match(p, state);
}
@ -4038,7 +4035,6 @@ bool ttwu_state_match(struct task_struct *p, unsigned int state, int *success)
*success = !!(match = __task_state_match(p, state));
#ifdef CONFIG_PREEMPT_RT
/*
* Saved state preserves the task state across blocking on
* an RT lock. If the state matches, set p::saved_state to
@ -4054,7 +4050,7 @@ bool ttwu_state_match(struct task_struct *p, unsigned int state, int *success)
*/
if (match < 0)
p->saved_state = TASK_RUNNING;
#endif
return match > 0;
}