mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-27 03:10:12 +00:00
00357f5ec5
The primary observation is that nohz enter/exit is always from the
current CPU, therefore NOHZ_TICK_STOPPED does not in fact need to be
an atomic.
Secondary is that we appear to have 2 nearly identical hooks in the
nohz enter code, set_cpu_sd_state_idle() and
nohz_balance_enter_idle(). Fold the whole set_cpu_sd_state thing into
nohz_balance_{enter,exit}_idle.
Removes an atomic op from both enter and exit paths.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
38 lines
1.1 KiB
C
38 lines
1.1 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
|
|
#ifndef _LINUX_SCHED_NOHZ_H
|
|
#define _LINUX_SCHED_NOHZ_H
|
|
|
|
/*
|
|
* This is the interface between the scheduler and nohz/dynticks:
|
|
*/
|
|
|
|
#if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON)
|
|
extern void cpu_load_update_nohz_start(void);
|
|
extern void cpu_load_update_nohz_stop(void);
|
|
#else
|
|
static inline void cpu_load_update_nohz_start(void) { }
|
|
static inline void cpu_load_update_nohz_stop(void) { }
|
|
#endif
|
|
|
|
#if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON)
|
|
extern void nohz_balance_enter_idle(int cpu);
|
|
extern int get_nohz_timer_target(void);
|
|
#else
|
|
static inline void nohz_balance_enter_idle(int cpu) { }
|
|
#endif
|
|
|
|
#ifdef CONFIG_NO_HZ_COMMON
|
|
void calc_load_nohz_start(void);
|
|
void calc_load_nohz_stop(void);
|
|
#else
|
|
static inline void calc_load_nohz_start(void) { }
|
|
static inline void calc_load_nohz_stop(void) { }
|
|
#endif /* CONFIG_NO_HZ_COMMON */
|
|
|
|
#if defined(CONFIG_NO_HZ_COMMON) && defined(CONFIG_SMP)
|
|
extern void wake_up_nohz_cpu(int cpu);
|
|
#else
|
|
static inline void wake_up_nohz_cpu(int cpu) { }
|
|
#endif
|
|
|
|
#endif /* _LINUX_SCHED_NOHZ_H */
|