Merge tag 'smp-urgent-2023-10-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull CPU hotplug fix from Ingo Molnar:
 "Fix a Longsoon build warning by harmonizing the
  arch_[un]register_cpu() prototypes between architectures"

* tag 'smp-urgent-2023-10-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  cpu-hotplug: Provide prototypes for arch CPU registration

Author: torvalds

arch/ia64/include/asm/cpu.h

@@ -15,9 +15,4 @@ DECLARE_PER_CPU(struct ia64_cpu, cpu_devices);
 
 DECLARE_PER_CPU(int, cpu_state);
 
-#ifdef CONFIG_HOTPLUG_CPU
-extern int arch_register_cpu(int num);
-extern void arch_unregister_cpu(int);
-#endif
-
 #endif /* _ASM_IA64_CPU_H_ */

arch/ia64/kernel/topology.c

@@ -59,7 +59,7 @@ void __ref arch_unregister_cpu(int num)
 }
 EXPORT_SYMBOL(arch_unregister_cpu);
 #else
-static int __init arch_register_cpu(int num)
+int __init arch_register_cpu(int num)
 {
 	return register_cpu(&sysfs_cpus[num].cpu, num);
 }

arch/x86/include/asm/cpu.h

@@ -28,8 +28,6 @@ struct x86_cpu {
 };
 
 #ifdef CONFIG_HOTPLUG_CPU
-extern int arch_register_cpu(int num);
-extern void arch_unregister_cpu(int);
 extern void soft_restart_cpu(void);
 #endif
 

arch/x86/kernel/topology.c

@@ -54,7 +54,7 @@ void arch_unregister_cpu(int num)
 EXPORT_SYMBOL(arch_unregister_cpu);
 #else /* CONFIG_HOTPLUG_CPU */
 
-static int __init arch_register_cpu(int num)
+int __init arch_register_cpu(int num)
 {
 	return register_cpu(&per_cpu(cpu_devices, num).cpu, num);
 }

drivers/acpi/acpi_processor.c

@@ -12,6 +12,7 @@
 #define pr_fmt(fmt) "ACPI: " fmt
 
 #include <linux/acpi.h>
+#include <linux/cpu.h>
 #include <linux/device.h>
 #include <linux/dmi.h>
 #include <linux/kernel.h>

include/acpi/processor.h

@@ -465,9 +465,4 @@ extern int acpi_processor_ffh_lpi_probe(unsigned int cpu);
 extern int acpi_processor_ffh_lpi_enter(struct acpi_lpi_state *lpi);
 #endif
 
-#ifdef CONFIG_ACPI_HOTPLUG_CPU
-extern int arch_register_cpu(int cpu);
-extern void arch_unregister_cpu(int cpu);
-#endif
-
 #endif

include/linux/cpu.h

@@ -80,6 +80,8 @@ extern __printf(4, 5)
 struct device *cpu_device_create(struct device *parent, void *drvdata,
 				 const struct attribute_group **groups,
 				 const char *fmt, ...);
+extern int arch_register_cpu(int cpu);
+extern void arch_unregister_cpu(int cpu);
 #ifdef CONFIG_HOTPLUG_CPU
 extern void unregister_cpu(struct cpu *cpu);
 extern ssize_t arch_cpu_probe(const char *, size_t);