89b3098703
Current arch_cpu_idle() is called with IRQs disabled, but will return with IRQs enabled. However, the very first thing the generic code does after calling arch_cpu_idle() is raw_local_irq_disable(). This means that architectures that can idle with IRQs disabled end up doing a pointless 'enable-disable' dance. Therefore, push this IRQ disabling into the idle function, meaning that those architectures can avoid the pointless IRQ state flipping. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Tested-by: Tony Lindgren <tony@atomide.com> Tested-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Gautham R. Shenoy <gautham.shenoy@amd.com> Acked-by: Mark Rutland <mark.rutland@arm.com> [arm64] Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Guo Ren <guoren@kernel.org> Acked-by: Frederic Weisbecker <frederic@kernel.org> Link: https://lore.kernel.org/r/20230112195540.618076436@infradead.org
59 lines
989 B
C
59 lines
989 B
C
// SPDX-License-Identifier: GPL-2.0
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/*
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* The idle loop for all SuperH platforms.
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*
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* Copyright (C) 2002 - 2009 Paul Mundt
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*/
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#include <linux/module.h>
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#include <linux/init.h>
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#include <linux/mm.h>
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#include <linux/pm.h>
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#include <linux/tick.h>
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#include <linux/preempt.h>
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#include <linux/thread_info.h>
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#include <linux/irqflags.h>
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#include <linux/smp.h>
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#include <linux/atomic.h>
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#include <asm/smp.h>
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#include <asm/bl_bit.h>
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static void (*sh_idle)(void);
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void default_idle(void)
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{
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set_bl_bit();
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raw_local_irq_enable();
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/* Isn't this racy ? */
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cpu_sleep();
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raw_local_irq_disable();
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clear_bl_bit();
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}
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void arch_cpu_idle_dead(void)
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{
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play_dead();
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}
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void arch_cpu_idle(void)
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{
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sh_idle();
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}
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void __init select_idle_routine(void)
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{
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/*
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* If a platform has set its own idle routine, leave it alone.
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*/
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if (!sh_idle)
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sh_idle = default_idle;
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}
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void stop_this_cpu(void *unused)
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{
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local_irq_disable();
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set_cpu_online(smp_processor_id(), false);
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for (;;)
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cpu_sleep();
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}
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