diff options
Diffstat (limited to 'include/linux/percpu.h')
-rw-r--r-- | include/linux/percpu.h | 100 |
1 files changed, 73 insertions, 27 deletions
diff --git a/include/linux/percpu.h b/include/linux/percpu.h index 3577ffd90d45..910beb0abea2 100644 --- a/include/linux/percpu.h +++ b/include/linux/percpu.h @@ -76,52 +76,98 @@ #ifdef CONFIG_SMP +#ifdef CONFIG_HAVE_DYNAMIC_PER_CPU_AREA + +/* minimum unit size, also is the maximum supported allocation size */ +#define PCPU_MIN_UNIT_SIZE (16UL << PAGE_SHIFT) + +/* + * PERCPU_DYNAMIC_RESERVE indicates the amount of free area to piggy + * back on the first chunk if arch is manually allocating and mapping + * it for faster access (as a part of large page mapping for example). + * Note that dynamic percpu allocator covers both static and dynamic + * areas, so these values are bigger than PERCPU_MODULE_RESERVE. + * + * On typical configuration with modules, the following values leave + * about 8k of free space on the first chunk after boot on both x86_32 + * and 64 when module support is enabled. When module support is + * disabled, it's much tighter. + */ +#ifndef PERCPU_DYNAMIC_RESERVE +# if BITS_PER_LONG > 32 +# ifdef CONFIG_MODULES +# define PERCPU_DYNAMIC_RESERVE (6 << PAGE_SHIFT) +# else +# define PERCPU_DYNAMIC_RESERVE (4 << PAGE_SHIFT) +# endif +# else +# ifdef CONFIG_MODULES +# define PERCPU_DYNAMIC_RESERVE (4 << PAGE_SHIFT) +# else +# define PERCPU_DYNAMIC_RESERVE (2 << PAGE_SHIFT) +# endif +# endif +#endif /* PERCPU_DYNAMIC_RESERVE */ + +extern void *pcpu_base_addr; + +typedef struct page * (*pcpu_get_page_fn_t)(unsigned int cpu, int pageno); +typedef void (*pcpu_populate_pte_fn_t)(unsigned long addr); + +extern size_t __init pcpu_setup_first_chunk(pcpu_get_page_fn_t get_page_fn, + size_t static_size, size_t unit_size, + size_t free_size, void *base_addr, + pcpu_populate_pte_fn_t populate_pte_fn); + +/* + * Use this to get to a cpu's version of the per-cpu object + * dynamically allocated. Non-atomic access to the current CPU's + * version should probably be combined with get_cpu()/put_cpu(). + */ +#define per_cpu_ptr(ptr, cpu) SHIFT_PERCPU_PTR((ptr), per_cpu_offset((cpu))) + +#else /* CONFIG_HAVE_DYNAMIC_PER_CPU_AREA */ + struct percpu_data { void *ptrs[1]; }; #define __percpu_disguise(pdata) (struct percpu_data *)~(unsigned long)(pdata) -/* - * Use this to get to a cpu's version of the per-cpu object dynamically - * allocated. Non-atomic access to the current CPU's version should - * probably be combined with get_cpu()/put_cpu(). - */ -#define percpu_ptr(ptr, cpu) \ -({ \ - struct percpu_data *__p = __percpu_disguise(ptr); \ - (__typeof__(ptr))__p->ptrs[(cpu)]; \ + +#define per_cpu_ptr(ptr, cpu) \ +({ \ + struct percpu_data *__p = __percpu_disguise(ptr); \ + (__typeof__(ptr))__p->ptrs[(cpu)]; \ }) -extern void *__percpu_alloc_mask(size_t size, gfp_t gfp, cpumask_t *mask); -extern void percpu_free(void *__pdata); +#endif /* CONFIG_HAVE_DYNAMIC_PER_CPU_AREA */ + +extern void *__alloc_percpu(size_t size, size_t align); +extern void free_percpu(void *__pdata); #else /* CONFIG_SMP */ -#define percpu_ptr(ptr, cpu) ({ (void)(cpu); (ptr); }) +#define per_cpu_ptr(ptr, cpu) ({ (void)(cpu); (ptr); }) -static __always_inline void *__percpu_alloc_mask(size_t size, gfp_t gfp, cpumask_t *mask) +static inline void *__alloc_percpu(size_t size, size_t align) { + /* + * Can't easily make larger alignment work with kmalloc. WARN + * on it. Larger alignment should only be used for module + * percpu sections on SMP for which this path isn't used. + */ + WARN_ON_ONCE(align > __alignof__(unsigned long long)); return kzalloc(size, gfp); } -static inline void percpu_free(void *__pdata) +static inline void free_percpu(void *p) { - kfree(__pdata); + kfree(p); } #endif /* CONFIG_SMP */ -#define percpu_alloc_mask(size, gfp, mask) \ - __percpu_alloc_mask((size), (gfp), &(mask)) - -#define percpu_alloc(size, gfp) percpu_alloc_mask((size), (gfp), cpu_online_map) - -/* (legacy) interface for use without CPU hotplug handling */ - -#define __alloc_percpu(size) percpu_alloc_mask((size), GFP_KERNEL, \ - cpu_possible_map) -#define alloc_percpu(type) (type *)__alloc_percpu(sizeof(type)) -#define free_percpu(ptr) percpu_free((ptr)) -#define per_cpu_ptr(ptr, cpu) percpu_ptr((ptr), (cpu)) +#define alloc_percpu(type) (type *)__alloc_percpu(sizeof(type), \ + __alignof__(type)) #endif /* __LINUX_PERCPU_H */ |