From 3e8eb22faee179798530b6a3d2639629fcf9d580 Mon Sep 17 00:00:00 2001 From: Heiko Carstens Date: Mon, 3 Jun 2019 15:22:25 +0200 Subject: [PATCH] s390: enforce CONFIG_HOTPLUG_CPU x86 and powerpc (partially) enforce already CONFIG_HOTPLUG_CPU. On s390 it is enabled on all distributions by default since ages. The only exception is our zfcpdump kernel. However to simplify testing, enforce HOTPLUG_CPU. This was suggested by Paul McKenney, since his rcutorture test environments for CONFIG_SMP=y only support HOTPLUG_CPU=y. Suggested-by: Paul E. McKenney Acked-by: Christian Borntraeger Signed-off-by: Heiko Carstens --- arch/s390/Kconfig | 5 ----- arch/s390/include/asm/smp.h | 5 ----- arch/s390/kernel/smp.c | 19 ------------------- 3 files changed, 29 deletions(-) diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig index bdf3b5fdea53..66be2d813951 100644 --- a/arch/s390/Kconfig +++ b/arch/s390/Kconfig @@ -413,11 +413,6 @@ config NR_CPUS config HOTPLUG_CPU def_bool y - prompt "Support for hot-pluggable CPUs" - help - Say Y here to be able to turn CPUs off and on. CPUs - can be controlled through /sys/devices/system/cpu/cpu#. - Say N if you want to disable CPU hotplug. # Some NUMA nodes have memory ranges that span # other nodes. Even though a pfn is valid and diff --git a/arch/s390/include/asm/smp.h b/arch/s390/include/asm/smp.h index 30ba1a3f88de..b157a81fb977 100644 --- a/arch/s390/include/asm/smp.h +++ b/arch/s390/include/asm/smp.h @@ -53,14 +53,9 @@ static inline int smp_get_base_cpu(int cpu) return cpu - (cpu % (smp_cpu_mtid + 1)); } -#ifdef CONFIG_HOTPLUG_CPU extern int smp_rescan_cpus(void); extern void __noreturn cpu_die(void); extern void __cpu_die(unsigned int cpu); extern int __cpu_disable(void); -#else -static inline int smp_rescan_cpus(void) { return 0; } -static inline void cpu_die(void) { } -#endif #endif /* __ASM_SMP_H */ diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c index 35fafa2b91a8..f00955940694 100644 --- a/arch/s390/kernel/smp.c +++ b/arch/s390/kernel/smp.c @@ -232,8 +232,6 @@ out: return -ENOMEM; } -#ifdef CONFIG_HOTPLUG_CPU - static void pcpu_free_lowcore(struct pcpu *pcpu) { unsigned long async_stack, nodat_stack, lowcore; @@ -253,8 +251,6 @@ static void pcpu_free_lowcore(struct pcpu *pcpu) free_pages(lowcore, LC_ORDER); } -#endif /* CONFIG_HOTPLUG_CPU */ - static void pcpu_prepare_secondary(struct pcpu *pcpu, int cpu) { struct lowcore *lc = pcpu->lowcore; @@ -895,8 +891,6 @@ static int __init _setup_possible_cpus(char *s) } early_param("possible_cpus", _setup_possible_cpus); -#ifdef CONFIG_HOTPLUG_CPU - int __cpu_disable(void) { unsigned long cregs[16]; @@ -937,8 +931,6 @@ void __noreturn cpu_die(void) for (;;) ; } -#endif /* CONFIG_HOTPLUG_CPU */ - void __init smp_fill_possible_mask(void) { unsigned int possible, sclp_max, cpu; @@ -996,7 +988,6 @@ int setup_profiling_timer(unsigned int multiplier) return 0; } -#ifdef CONFIG_HOTPLUG_CPU static ssize_t cpu_configure_show(struct device *dev, struct device_attribute *attr, char *buf) { @@ -1073,7 +1064,6 @@ out: return rc ? rc : count; } static DEVICE_ATTR(configure, 0644, cpu_configure_show, cpu_configure_store); -#endif /* CONFIG_HOTPLUG_CPU */ static ssize_t show_cpu_address(struct device *dev, struct device_attribute *attr, char *buf) @@ -1083,9 +1073,7 @@ static ssize_t show_cpu_address(struct device *dev, static DEVICE_ATTR(address, 0444, show_cpu_address, NULL); static struct attribute *cpu_common_attrs[] = { -#ifdef CONFIG_HOTPLUG_CPU &dev_attr_configure.attr, -#endif &dev_attr_address.attr, NULL, }; @@ -1144,15 +1132,11 @@ static int smp_add_present_cpu(int cpu) out_topology: sysfs_remove_group(&s->kobj, &cpu_common_attr_group); out_cpu: -#ifdef CONFIG_HOTPLUG_CPU unregister_cpu(c); -#endif out: return rc; } -#ifdef CONFIG_HOTPLUG_CPU - int __ref smp_rescan_cpus(void) { struct sclp_core_info *info; @@ -1188,17 +1172,14 @@ static ssize_t __ref rescan_store(struct device *dev, return rc ? rc : count; } static DEVICE_ATTR_WO(rescan); -#endif /* CONFIG_HOTPLUG_CPU */ static int __init s390_smp_init(void) { int cpu, rc = 0; -#ifdef CONFIG_HOTPLUG_CPU rc = device_create_file(cpu_subsys.dev_root, &dev_attr_rescan); if (rc) return rc; -#endif for_each_present_cpu(cpu) { rc = smp_add_present_cpu(cpu); if (rc) -- 2.30.2