Commit 72b11aa7 authored by Thomas Gleixner's avatar Thomas Gleixner Committed by Peter Zijlstra
Browse files

riscv: Switch to hotplug core state synchronization 



Switch to the CPU hotplug core state tracking and synchronization
mechanim. No functional change intended.

Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: default avatarPalmer Dabbelt <palmer@rivosinc.com>
Tested-by: default avatarMichael Kelley <mikelley@microsoft.com>
Tested-by: default avatarOleksandr 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
parent 51e0efe1

arch/riscv/Kconfig

+1 −0
Original line number Diff line number Diff line
@@ -122,6 +122,7 @@ config RISCV 
	select HAVE_RSEQ

	select HAVE_STACKPROTECTOR

	select HAVE_SYSCALL_TRACEPOINTS

	select HOTPLUG_CORE_SYNC_DEAD if HOTPLUG_CPU

	select IRQ_DOMAIN

	select IRQ_FORCED_THREADING

	select KASAN_VMALLOC if KASAN

arch/riscv/include/asm/smp.h

+1 −1
Original line number Diff line number Diff line
@@ -70,7 +70,7 @@ asmlinkage void smp_callin(void); 


#if defined CONFIG_HOTPLUG_CPU

int __cpu_disable(void);

void __cpu_die(unsigned int cpu);

static inline void __cpu_die(unsigned int cpu) { }

#endif /* CONFIG_HOTPLUG_CPU */



#else

arch/riscv/kernel/cpu-hotplug.c

+7 −7
Original line number Diff line number Diff line
@@ -8,6 +8,7 @@ 
#include <linux/sched.h>

#include <linux/err.h>

#include <linux/irq.h>

#include <linux/cpuhotplug.h>

#include <linux/cpu.h>

#include <linux/sched/hotplug.h>

#include <asm/irq.h>
@@ -49,17 +50,15 @@ int __cpu_disable(void) 
	return ret;

}



#ifdef CONFIG_HOTPLUG_CPU

/*

 * Called on the thread which is asking for a CPU to be shutdown.

 * Called on the thread which is asking for a CPU to be shutdown, if the

 * CPU reported dead to the hotplug core.

 */

void __cpu_die(unsigned int cpu)

void arch_cpuhp_cleanup_dead_cpu(unsigned int cpu)

{

	int ret = 0;



	if (!cpu_wait_death(cpu, 5)) {

		pr_err("CPU %u: didn't die\n", cpu);

		return;

	}

	pr_notice("CPU%u: off\n", cpu);



	/* Verify from the firmware if the cpu is really stopped*/
@@ -76,9 +75,10 @@ void __noreturn arch_cpu_idle_dead(void) 
{

	idle_task_exit();



	(void)cpu_report_death();

	cpuhp_ap_report_dead();



	cpu_ops[smp_processor_id()]->cpu_stop();

	/* It should never reach here */

	BUG();

}

#endif