LXR linux/arch/s390/include/asm/smp.h

   1/* SPDX-License-Identifier: GPL-2.0 */
   2/*
   3 *    Copyright IBM Corp. 1999, 2012
   4 *    Author(s): Denis Joseph Barrow,
   5 *               Martin Schwidefsky <schwidefsky@de.ibm.com>,
   6 *               Heiko Carstens <heiko.carstens@de.ibm.com>,
   7 */
   8#ifndef __ASM_SMP_H
   9#define __ASM_SMP_H
  10
  11#include <asm/sigp.h>
  12
  13#ifdef CONFIG_SMP
  14
  15#include <asm/lowcore.h>
  16
  17#define raw_smp_processor_id()  (S390_lowcore.cpu_nr)
  18
  19extern struct mutex smp_cpu_state_mutex;
  20extern unsigned int smp_cpu_mt_shift;
  21extern unsigned int smp_cpu_mtid;
  22extern __vector128 __initdata boot_cpu_vector_save_area[__NUM_VXRS];
  23
  24extern int __cpu_up(unsigned int cpu, struct task_struct *tidle);
  25
  26extern void arch_send_call_function_single_ipi(int cpu);
  27extern void arch_send_call_function_ipi_mask(const struct cpumask *mask);
  28
  29extern void smp_call_online_cpu(void (*func)(void *), void *);
  30extern void smp_call_ipl_cpu(void (*func)(void *), void *);
  31extern void smp_emergency_stop(void);
  32
  33extern int smp_find_processor_id(u16 address);
  34extern int smp_store_status(int cpu);
  35extern void smp_save_dump_cpus(void);
  36extern int smp_vcpu_scheduled(int cpu);
  37extern void smp_yield_cpu(int cpu);
  38extern void smp_cpu_set_polarization(int cpu, int val);
  39extern int smp_cpu_get_polarization(int cpu);
  40extern void smp_fill_possible_mask(void);
  41extern void smp_detect_cpus(void);
  42
  43#else /* CONFIG_SMP */
  44
  45#define smp_cpu_mtid    0
  46
  47static inline void smp_call_ipl_cpu(void (*func)(void *), void *data)
  48{
  49        func(data);
  50}
  51
  52static inline void smp_call_online_cpu(void (*func)(void *), void *data)
  53{
  54        func(data);
  55}
  56
  57static inline void smp_emergency_stop(void)
  58{
  59}
  60
  61static inline int smp_find_processor_id(u16 address) { return 0; }
  62static inline int smp_store_status(int cpu) { return 0; }
  63static inline int smp_vcpu_scheduled(int cpu) { return 1; }
  64static inline void smp_yield_cpu(int cpu) { }
  65static inline void smp_fill_possible_mask(void) { }
  66static inline void smp_detect_cpus(void) { }
  67
  68#endif /* CONFIG_SMP */
  69
  70static inline void smp_stop_cpu(void)
  71{
  72        u16 pcpu = stap();
  73
  74        for (;;) {
  75                __pcpu_sigp(pcpu, SIGP_STOP, 0, NULL);
  76                cpu_relax();
  77        }
  78}
  79
  80/* Return thread 0 CPU number as base CPU */
  81static inline int smp_get_base_cpu(int cpu)
  82{
  83        return cpu - (cpu % (smp_cpu_mtid + 1));
  84}
  85
  86#ifdef CONFIG_HOTPLUG_CPU
  87extern int smp_rescan_cpus(void);
  88extern void __noreturn cpu_die(void);
  89extern void __cpu_die(unsigned int cpu);
  90extern int __cpu_disable(void);
  91#else
  92static inline int smp_rescan_cpus(void) { return 0; }
  93static inline void cpu_die(void) { }
  94#endif
  95
  96#endif /* __ASM_SMP_H */
  97