diff --git a/arch/Kconfig b/arch/Kconfig index dc81b34c5d8..78a35e9dc10 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -109,3 +109,6 @@ config HAVE_CLK config HAVE_DMA_API_DEBUG bool + +config HAVE_DEFAULT_NO_SPIN_MUTEXES + bool diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig index dcb667c4375..2eca5fe0e75 100644 --- a/arch/s390/Kconfig +++ b/arch/s390/Kconfig @@ -82,6 +82,7 @@ config S390 select USE_GENERIC_SMP_HELPERS if SMP select HAVE_SYSCALL_WRAPPERS select HAVE_FUNCTION_TRACER + select HAVE_DEFAULT_NO_SPIN_MUTEXES select HAVE_OPROFILE select HAVE_KPROBES select HAVE_KRETPROBES diff --git a/include/asm-generic/percpu.h b/include/asm-generic/percpu.h index 00f45ff081a..b0e63c672eb 100644 --- a/include/asm-generic/percpu.h +++ b/include/asm-generic/percpu.h @@ -80,56 +80,4 @@ extern void setup_per_cpu_areas(void); #define DECLARE_PER_CPU(type, name) extern PER_CPU_ATTRIBUTES \ __typeof__(type) per_cpu_var(name) -/* - * Optional methods for optimized non-lvalue per-cpu variable access. - * - * @var can be a percpu variable or a field of it and its size should - * equal char, int or long. percpu_read() evaluates to a lvalue and - * all others to void. - * - * These operations are guaranteed to be atomic w.r.t. preemption. - * The generic versions use plain get/put_cpu_var(). Archs are - * encouraged to implement single-instruction alternatives which don't - * require preemption protection. - */ -#ifndef percpu_read -# define percpu_read(var) \ - ({ \ - typeof(per_cpu_var(var)) __tmp_var__; \ - __tmp_var__ = get_cpu_var(var); \ - put_cpu_var(var); \ - __tmp_var__; \ - }) -#endif - -#define __percpu_generic_to_op(var, val, op) \ -do { \ - get_cpu_var(var) op val; \ - put_cpu_var(var); \ -} while (0) - -#ifndef percpu_write -# define percpu_write(var, val) __percpu_generic_to_op(var, (val), =) -#endif - -#ifndef percpu_add -# define percpu_add(var, val) __percpu_generic_to_op(var, (val), +=) -#endif - -#ifndef percpu_sub -# define percpu_sub(var, val) __percpu_generic_to_op(var, (val), -=) -#endif - -#ifndef percpu_and -# define percpu_and(var, val) __percpu_generic_to_op(var, (val), &=) -#endif - -#ifndef percpu_or -# define percpu_or(var, val) __percpu_generic_to_op(var, (val), |=) -#endif - -#ifndef percpu_xor -# define percpu_xor(var, val) __percpu_generic_to_op(var, (val), ^=) -#endif - #endif /* _ASM_GENERIC_PERCPU_H_ */ diff --git a/include/linux/percpu.h b/include/linux/percpu.h index ee5615d6521..cfda2d5ad31 100644 --- a/include/linux/percpu.h +++ b/include/linux/percpu.h @@ -168,4 +168,56 @@ static inline void free_percpu(void *p) #define alloc_percpu(type) (type *)__alloc_percpu(sizeof(type), \ __alignof__(type)) +/* + * Optional methods for optimized non-lvalue per-cpu variable access. + * + * @var can be a percpu variable or a field of it and its size should + * equal char, int or long. percpu_read() evaluates to a lvalue and + * all others to void. + * + * These operations are guaranteed to be atomic w.r.t. preemption. + * The generic versions use plain get/put_cpu_var(). Archs are + * encouraged to implement single-instruction alternatives which don't + * require preemption protection. + */ +#ifndef percpu_read +# define percpu_read(var) \ + ({ \ + typeof(per_cpu_var(var)) __tmp_var__; \ + __tmp_var__ = get_cpu_var(var); \ + put_cpu_var(var); \ + __tmp_var__; \ + }) +#endif + +#define __percpu_generic_to_op(var, val, op) \ +do { \ + get_cpu_var(var) op val; \ + put_cpu_var(var); \ +} while (0) + +#ifndef percpu_write +# define percpu_write(var, val) __percpu_generic_to_op(var, (val), =) +#endif + +#ifndef percpu_add +# define percpu_add(var, val) __percpu_generic_to_op(var, (val), +=) +#endif + +#ifndef percpu_sub +# define percpu_sub(var, val) __percpu_generic_to_op(var, (val), -=) +#endif + +#ifndef percpu_and +# define percpu_and(var, val) __percpu_generic_to_op(var, (val), &=) +#endif + +#ifndef percpu_or +# define percpu_or(var, val) __percpu_generic_to_op(var, (val), |=) +#endif + +#ifndef percpu_xor +# define percpu_xor(var, val) __percpu_generic_to_op(var, (val), ^=) +#endif + #endif /* __LINUX_PERCPU_H */ diff --git a/kernel/mutex.c b/kernel/mutex.c index 5d79781394a..507cf2b5e9f 100644 --- a/kernel/mutex.c +++ b/kernel/mutex.c @@ -148,7 +148,8 @@ __mutex_lock_common(struct mutex *lock, long state, unsigned int subclass, preempt_disable(); mutex_acquire(&lock->dep_map, subclass, 0, ip); -#if defined(CONFIG_SMP) && !defined(CONFIG_DEBUG_MUTEXES) +#if defined(CONFIG_SMP) && !defined(CONFIG_DEBUG_MUTEXES) && \ + !defined(CONFIG_HAVE_DEFAULT_NO_SPIN_MUTEXES) /* * Optimistic spinning. *