forked from mirrors/linux
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 */
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#ifndef _LINUX_SCHED_NOHZ_H
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#define _LINUX_SCHED_NOHZ_H
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/*
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* This is the interface between the scheduler and nohz/dynticks:
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*/
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#if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON)
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extern void cpu_load_update_nohz_start(void);
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extern void cpu_load_update_nohz_stop(void);
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#else
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static inline void cpu_load_update_nohz_start(void) { }
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static inline void cpu_load_update_nohz_stop(void) { }
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#endif
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#if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON)
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extern void nohz_balance_enter_idle(int cpu);
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extern int get_nohz_timer_target(void);
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#else
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static inline void nohz_balance_enter_idle(int cpu) { }
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#endif
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#ifdef CONFIG_NO_HZ_COMMON
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void calc_load_nohz_start(void);
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void calc_load_nohz_stop(void);
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#else
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static inline void calc_load_nohz_start(void) { }
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static inline void calc_load_nohz_stop(void) { }
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#endif /* CONFIG_NO_HZ_COMMON */
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#if defined(CONFIG_NO_HZ_COMMON) && defined(CONFIG_SMP)
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extern void wake_up_nohz_cpu(int cpu);
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#else
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static inline void wake_up_nohz_cpu(int cpu) { }
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#endif
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#endif /* _LINUX_SCHED_NOHZ_H */
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