linux/arch/x86/include/asm/cpu.h
Paul E. McKenney 2a442c9c64 x86: Use common outgoing-CPU-notification code
This commit removes the open-coded CPU-offline notification with new
common code.  Among other things, this change avoids calling scheduler
code using RCU from an offline CPU that RCU is ignoring.  It also allows
Xen to notice at online time that the CPU did not go offline correctly.
Note that Xen has the surviving CPU carry out some cleanup operations,
so if the surviving CPU times out, these cleanup operations might have
been carried out while the outgoing CPU was still running.  It might
therefore be unwise to bring this CPU back online, and this commit
avoids doing so.

Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: <x86@kernel.org>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: <xen-devel@lists.xenproject.org>
2015-03-11 13:22:35 -07:00

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813 B
C

#ifndef _ASM_X86_CPU_H
#define _ASM_X86_CPU_H
#include <linux/device.h>
#include <linux/cpu.h>
#include <linux/topology.h>
#include <linux/nodemask.h>
#include <linux/percpu.h>
#ifdef CONFIG_SMP
extern void prefill_possible_map(void);
#else /* CONFIG_SMP */
static inline void prefill_possible_map(void) {}
#define cpu_physical_id(cpu) boot_cpu_physical_apicid
#define safe_smp_processor_id() 0
#define stack_smp_processor_id() 0
#endif /* CONFIG_SMP */
struct x86_cpu {
struct cpu cpu;
};
#ifdef CONFIG_HOTPLUG_CPU
extern int arch_register_cpu(int num);
extern void arch_unregister_cpu(int);
extern void start_cpu0(void);
#ifdef CONFIG_DEBUG_HOTPLUG_CPU0
extern int _debug_hotplug_cpu(int cpu, int action);
#endif
#endif
int mwait_usable(const struct cpuinfo_x86 *);
#endif /* _ASM_X86_CPU_H */