Commit 67626fad authored by Heiko Carstens's avatar Heiko Carstens
Browse files

s390: enforce CONFIG_SMP 



There never have been distributions that shiped with CONFIG_SMP=n for
s390. In addition the kernel currently doesn't even compile with
CONFIG_SMP=n for s390. Most likely it wouldn't even work, even if we
fix the compile error, since nobody tests it, since there is no use
case that I can think of.
Therefore simply enforce CONFIG_SMP and get rid of some more or
less unused code.

Reviewed-by: default avatarChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: default avatarHeiko Carstens <heiko.carstens@de.ibm.com>
parent 753469a2

arch/s390/Kconfig

+2 −23
Original line number Diff line number Diff line
@@ -30,7 +30,7 @@ config GENERIC_BUG_RELATIVE_POINTERS 
	def_bool y



config GENERIC_LOCKBREAK

	def_bool y if SMP && PREEMPT

	def_bool y if PREEMPT



config PGSTE

	def_bool y if KVM
@@ -113,7 +113,6 @@ config S390 
	select DYNAMIC_FTRACE if FUNCTION_TRACER

	select GENERIC_CLOCKEVENTS

	select GENERIC_CPU_AUTOPROBE

	select GENERIC_CPU_DEVICES if !SMP

	select GENERIC_CPU_VULNERABILITIES

	select GENERIC_FIND_FIRST_BIT

	select GENERIC_SMP_IDLE_THREAD
@@ -399,27 +398,10 @@ config SYSVIPC_COMPAT 


config SMP

	def_bool y

	prompt "Symmetric multi-processing support"

	---help---

	  This enables support for systems with more than one CPU. If you have

	  a system with only one CPU, like most personal computers, say N. If

	  you have a system with more than one CPU, say Y.



	  If you say N here, the kernel will run on uni- and multiprocessor

	  machines, but will use only one CPU of a multiprocessor machine. If

	  you say Y here, the kernel will run on many, but not all,

	  uniprocessor machines. On a uniprocessor machine, the kernel

	  will run faster if you say N here.



	  See also the SMP-HOWTO available at

	  <http://www.tldp.org/docs.html#howto>.



	  Even if you don't know what to do here, say Y.



config NR_CPUS

	int "Maximum number of CPUs (2-512)"

	range 2 512

	depends on SMP

	default "64"

	help

	  This allows you to specify the maximum number of CPUs which this
@@ -432,7 +414,6 @@ config NR_CPUS 
config HOTPLUG_CPU

	def_bool y

	prompt "Support for hot-pluggable CPUs"

	depends on SMP

	help

	  Say Y here to be able to turn CPUs off and on. CPUs

	  can be controlled through /sys/devices/system/cpu/cpu#.
@@ -448,7 +429,7 @@ config NODES_SPAN_OTHER_NODES 


config NUMA

	bool "NUMA support"

	depends on SMP && SCHED_TOPOLOGY

	depends on SCHED_TOPOLOGY

	default n

	help

	  Enable NUMA support
@@ -523,7 +504,6 @@ config SCHED_DRAWER 
config SCHED_TOPOLOGY

	def_bool y

	prompt "Topology scheduler support"

	depends on SMP

	select SCHED_SMT

	select SCHED_MC

	select SCHED_BOOK
@@ -829,7 +809,6 @@ menu "Dump support" 


config CRASH_DUMP

	bool "kernel crash dumps"

	depends on SMP

	select KEXEC

	help

	  Generate crash dump after being started by kexec.

arch/s390/include/asm/ctl_reg.h

+2 −7
Original line number Diff line number Diff line
@@ -112,13 +112,8 @@ union ctlreg2 { 
	};

};



#ifdef CONFIG_SMP

#define ctl_set_bit(cr, bit) smp_ctl_set_bit(cr, bit)

#define ctl_clear_bit(cr, bit) smp_ctl_clear_bit(cr, bit)

#else

# define ctl_set_bit(cr, bit) __ctl_set_bit(cr, bit)

# define ctl_clear_bit(cr, bit) __ctl_clear_bit(cr, bit)

#endif



#endif /* __ASSEMBLY__ */

#endif /* __ASM_CTL_REG_H */

arch/s390/include/asm/percpu.h

+1 −1
Original line number Diff line number Diff line
@@ -16,7 +16,7 @@ 
 * per cpu area, use weak definitions to force the compiler to

 * generate external references.

 */

#if defined(CONFIG_SMP) && defined(MODULE)

#if defined(MODULE)

#define ARCH_NEEDS_WEAK_PER_CPU

#endif

arch/s390/include/asm/smp.h

+0 −30
Original line number Diff line number Diff line
@@ -9,9 +9,6 @@ 
#define __ASM_SMP_H



#include <asm/sigp.h>



#ifdef CONFIG_SMP



#include <asm/lowcore.h>



#define raw_smp_processor_id()	(S390_lowcore.cpu_nr)
@@ -40,33 +37,6 @@ extern int smp_cpu_get_polarization(int cpu); 
extern void smp_fill_possible_mask(void);

extern void smp_detect_cpus(void);



#else /* CONFIG_SMP */



#define smp_cpu_mtid	0



static inline void smp_call_ipl_cpu(void (*func)(void *), void *data)

{

	func(data);

}



static inline void smp_call_online_cpu(void (*func)(void *), void *data)

{

	func(data);

}



static inline void smp_emergency_stop(void)

{

}



static inline int smp_find_processor_id(u16 address) { return 0; }

static inline int smp_store_status(int cpu) { return 0; }

static inline int smp_vcpu_scheduled(int cpu) { return 1; }

static inline void smp_yield_cpu(int cpu) { }

static inline void smp_fill_possible_mask(void) { }

static inline void smp_detect_cpus(void) { }



#endif /* CONFIG_SMP */



static inline void smp_stop_cpu(void)

{

	u16 pcpu = stap();

arch/s390/include/asm/spinlock.h

+0 −4
Original line number Diff line number Diff line
@@ -20,11 +20,7 @@ 


extern int spin_retry;



#ifndef CONFIG_SMP

static inline bool arch_vcpu_is_preempted(int cpu) { return false; }

#else

bool arch_vcpu_is_preempted(int cpu);

#endif



#define vcpu_is_preempted arch_vcpu_is_preempted