forked from mirrors/linux
		
	 b00742d399
			
		
	
	
		b00742d399
		
	
	
	
	
		
			
			Rather than using a single constant PERCPU_ENOUGH_ROOM, compute it as the sum of kernel_percpu + PERCPU_MODULE_RESERVE. This is now common to all architectures; if an architecture wants to set PERCPU_ENOUGH_ROOM to something special, then it may do so (ia64 is the only one which does). Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com> Signed-off-by: Andi Kleen <ak@suse.de> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Andi Kleen <ak@suse.de>
		
			
				
	
	
		
			113 lines
		
	
	
	
		
			3.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			113 lines
		
	
	
	
		
			3.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| #ifndef __LINUX_PERCPU_H
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| #define __LINUX_PERCPU_H
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| 
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| #include <linux/spinlock.h> /* For preempt_disable() */
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| #include <linux/slab.h> /* For kmalloc() */
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| #include <linux/smp.h>
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| #include <linux/string.h> /* For memset() */
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| #include <linux/cpumask.h>
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| 
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| #include <asm/percpu.h>
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| 
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| /* Enough to cover all DEFINE_PER_CPUs in kernel, including modules. */
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| #ifndef PERCPU_ENOUGH_ROOM
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| #ifdef CONFIG_MODULES
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| #define PERCPU_MODULE_RESERVE	8192
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| #else
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| #define PERCPU_MODULE_RESERVE	0
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| #endif
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| 
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| #define PERCPU_ENOUGH_ROOM						\
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| 	(__per_cpu_end - __per_cpu_start + PERCPU_MODULE_RESERVE)
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| #endif	/* PERCPU_ENOUGH_ROOM */
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| 
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| /*
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|  * Must be an lvalue. Since @var must be a simple identifier,
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|  * we force a syntax error here if it isn't.
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|  */
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| #define get_cpu_var(var) (*({				\
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| 	extern int simple_identifier_##var(void);	\
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| 	preempt_disable();				\
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| 	&__get_cpu_var(var); }))
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| #define put_cpu_var(var) preempt_enable()
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| 
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| #ifdef CONFIG_SMP
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| 
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| struct percpu_data {
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| 	void *ptrs[NR_CPUS];
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| };
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| 
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| #define __percpu_disguise(pdata) (struct percpu_data *)~(unsigned long)(pdata)
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| /* 
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|  * Use this to get to a cpu's version of the per-cpu object dynamically
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|  * allocated. Non-atomic access to the current CPU's version should
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|  * probably be combined with get_cpu()/put_cpu().
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|  */ 
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| #define percpu_ptr(ptr, cpu)                              \
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| ({                                                        \
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|         struct percpu_data *__p = __percpu_disguise(ptr); \
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|         (__typeof__(ptr))__p->ptrs[(cpu)];	          \
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| })
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| 
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| extern void *percpu_populate(void *__pdata, size_t size, gfp_t gfp, int cpu);
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| extern void percpu_depopulate(void *__pdata, int cpu);
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| extern int __percpu_populate_mask(void *__pdata, size_t size, gfp_t gfp,
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| 				  cpumask_t *mask);
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| extern void __percpu_depopulate_mask(void *__pdata, cpumask_t *mask);
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| extern void *__percpu_alloc_mask(size_t size, gfp_t gfp, cpumask_t *mask);
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| extern void percpu_free(void *__pdata);
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| 
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| #else /* CONFIG_SMP */
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| 
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| #define percpu_ptr(ptr, cpu) ({ (void)(cpu); (ptr); })
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| 
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| static inline void percpu_depopulate(void *__pdata, int cpu)
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| {
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| }
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| 
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| static inline void __percpu_depopulate_mask(void *__pdata, cpumask_t *mask)
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| {
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| }
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| 
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| static inline void *percpu_populate(void *__pdata, size_t size, gfp_t gfp,
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| 				    int cpu)
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| {
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| 	return percpu_ptr(__pdata, cpu);
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| }
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| 
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| static inline int __percpu_populate_mask(void *__pdata, size_t size, gfp_t gfp,
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| 					 cpumask_t *mask)
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| {
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| 	return 0;
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| }
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| 
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| static __always_inline void *__percpu_alloc_mask(size_t size, gfp_t gfp, cpumask_t *mask)
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| {
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| 	return kzalloc(size, gfp);
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| }
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| 
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| static inline void percpu_free(void *__pdata)
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| {
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| 	kfree(__pdata);
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| }
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| 
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| #endif /* CONFIG_SMP */
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| 
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| #define percpu_populate_mask(__pdata, size, gfp, mask) \
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| 	__percpu_populate_mask((__pdata), (size), (gfp), &(mask))
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| #define percpu_depopulate_mask(__pdata, mask) \
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| 	__percpu_depopulate_mask((__pdata), &(mask))
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| #define percpu_alloc_mask(size, gfp, mask) \
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| 	__percpu_alloc_mask((size), (gfp), &(mask))
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| 
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| #define percpu_alloc(size, gfp) percpu_alloc_mask((size), (gfp), cpu_online_map)
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| 
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| /* (legacy) interface for use without CPU hotplug handling */
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| 
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| #define __alloc_percpu(size)	percpu_alloc_mask((size), GFP_KERNEL, \
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| 						  cpu_possible_map)
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| #define alloc_percpu(type)	(type *)__alloc_percpu(sizeof(type))
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| #define free_percpu(ptr)	percpu_free((ptr))
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| #define per_cpu_ptr(ptr, cpu)	percpu_ptr((ptr), (cpu))
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| 
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| #endif /* __LINUX_PERCPU_H */
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