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	Switch to the CPU hotplug core state tracking and synchronization mechanim. No functional change intended. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Palmer Dabbelt <palmer@rivosinc.com> Tested-by: Michael Kelley <mikelley@microsoft.com> Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name> Tested-by: Helge Deller <deller@gmx.de> # parisc Tested-by: Guilherme G. Piccoli <gpiccoli@igalia.com> # Steam Deck Link: https://lore.kernel.org/r/20230512205256.916055844@linutronix.de
		
			
				
	
	
		
			84 lines
		
	
	
	
		
			1.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			84 lines
		
	
	
	
		
			1.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
// SPDX-License-Identifier: GPL-2.0
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/*
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 * Copyright (C) 2020 Western Digital Corporation or its affiliates.
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 */
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#include <linux/kernel.h>
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#include <linux/mm.h>
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#include <linux/sched.h>
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#include <linux/err.h>
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#include <linux/irq.h>
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#include <linux/cpuhotplug.h>
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#include <linux/cpu.h>
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#include <linux/sched/hotplug.h>
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#include <asm/irq.h>
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#include <asm/cpu_ops.h>
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#include <asm/numa.h>
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#include <asm/smp.h>
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bool cpu_has_hotplug(unsigned int cpu)
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{
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	if (cpu_ops[cpu]->cpu_stop)
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		return true;
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	return false;
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}
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/*
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 * __cpu_disable runs on the processor to be shutdown.
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 */
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int __cpu_disable(void)
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{
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	int ret = 0;
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	unsigned int cpu = smp_processor_id();
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	if (!cpu_ops[cpu] || !cpu_ops[cpu]->cpu_stop)
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		return -EOPNOTSUPP;
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	if (cpu_ops[cpu]->cpu_disable)
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		ret = cpu_ops[cpu]->cpu_disable(cpu);
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	if (ret)
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		return ret;
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	remove_cpu_topology(cpu);
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	numa_remove_cpu(cpu);
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	set_cpu_online(cpu, false);
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	riscv_ipi_disable();
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	irq_migrate_all_off_this_cpu();
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	return ret;
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}
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#ifdef CONFIG_HOTPLUG_CPU
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/*
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 * Called on the thread which is asking for a CPU to be shutdown, if the
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 * CPU reported dead to the hotplug core.
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 */
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void arch_cpuhp_cleanup_dead_cpu(unsigned int cpu)
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{
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	int ret = 0;
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	pr_notice("CPU%u: off\n", cpu);
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	/* Verify from the firmware if the cpu is really stopped*/
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	if (cpu_ops[cpu]->cpu_is_stopped)
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		ret = cpu_ops[cpu]->cpu_is_stopped(cpu);
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	if (ret)
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		pr_warn("CPU%d may not have stopped: %d\n", cpu, ret);
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}
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/*
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 * Called from the idle thread for the CPU which has been shutdown.
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 */
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void __noreturn arch_cpu_idle_dead(void)
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{
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	idle_task_exit();
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	cpuhp_ap_report_dead();
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	cpu_ops[smp_processor_id()]->cpu_stop();
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	/* It should never reach here */
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	BUG();
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}
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#endif
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