1 #ifndef __LINUX_PERCPU_H 2 #define __LINUX_PERCPU_H 3 4 #include <linux/mmdebug.h> 5 #include <linux/preempt.h> 6 #include <linux/smp.h> 7 #include <linux/cpumask.h> 8 #include <linux/printk.h> 9 #include <linux/pfn.h> 10 #include <linux/init.h> 11 12 #include <asm/percpu.h> 13 14 /* enough to cover all DEFINE_PER_CPUs in modules */ 15 #ifdef CONFIG_MODULES 16 #define PERCPU_MODULE_RESERVE (8 << 10) 17 #else 18 #define PERCPU_MODULE_RESERVE 0 19 #endif 20 21 /* minimum unit size, also is the maximum supported allocation size */ 22 #define PCPU_MIN_UNIT_SIZE PFN_ALIGN(32 << 10) 23 24 /* minimum allocation size and shift in bytes */ 25 #define PCPU_MIN_ALLOC_SHIFT 2 26 #define PCPU_MIN_ALLOC_SIZE (1 << PCPU_MIN_ALLOC_SHIFT) 27 28 /* 29 * Percpu allocator can serve percpu allocations before slab is 30 * initialized which allows slab to depend on the percpu allocator. 31 * The following two parameters decide how much resource to 32 * preallocate for this. Keep PERCPU_DYNAMIC_RESERVE equal to or 33 * larger than PERCPU_DYNAMIC_EARLY_SIZE. 34 */ 35 #define PERCPU_DYNAMIC_EARLY_SLOTS 128 36 #define PERCPU_DYNAMIC_EARLY_SIZE (12 << 10) 37 38 /* 39 * PERCPU_DYNAMIC_RESERVE indicates the amount of free area to piggy 40 * back on the first chunk for dynamic percpu allocation if arch is 41 * manually allocating and mapping it for faster access (as a part of 42 * large page mapping for example). 43 * 44 * The following values give between one and two pages of free space 45 * after typical minimal boot (2-way SMP, single disk and NIC) with 46 * both defconfig and a distro config on x86_64 and 32. More 47 * intelligent way to determine this would be nice. 48 */ 49 #if BITS_PER_LONG > 32 50 #define PERCPU_DYNAMIC_RESERVE (28 << 10) 51 #else 52 #define PERCPU_DYNAMIC_RESERVE (20 << 10) 53 #endif 54 55 extern void *pcpu_base_addr; 56 extern const unsigned long *pcpu_unit_offsets; 57 58 struct pcpu_group_info { 59 int nr_units; /* aligned # of units */ 60 unsigned long base_offset; /* base address offset */ 61 unsigned int *cpu_map; /* unit->cpu map, empty 62 * entries contain NR_CPUS */ 63 }; 64 65 struct pcpu_alloc_info { 66 size_t static_size; 67 size_t reserved_size; 68 size_t dyn_size; 69 size_t unit_size; 70 size_t atom_size; 71 size_t alloc_size; 72 size_t __ai_size; /* internal, don't use */ 73 int nr_groups; /* 0 if grouping unnecessary */ 74 struct pcpu_group_info groups[]; 75 }; 76 77 enum pcpu_fc { 78 PCPU_FC_AUTO, 79 PCPU_FC_EMBED, 80 PCPU_FC_PAGE, 81 82 PCPU_FC_NR, 83 }; 84 extern const char * const pcpu_fc_names[PCPU_FC_NR]; 85 86 extern enum pcpu_fc pcpu_chosen_fc; 87 88 typedef void * (*pcpu_fc_alloc_fn_t)(unsigned int cpu, size_t size, 89 size_t align); 90 typedef void (*pcpu_fc_free_fn_t)(void *ptr, size_t size); 91 typedef void (*pcpu_fc_populate_pte_fn_t)(unsigned long addr); 92 typedef int (pcpu_fc_cpu_distance_fn_t)(unsigned int from, unsigned int to); 93 94 extern struct pcpu_alloc_info * __init pcpu_alloc_alloc_info(int nr_groups, 95 int nr_units); 96 extern void __init pcpu_free_alloc_info(struct pcpu_alloc_info *ai); 97 98 extern int __init pcpu_setup_first_chunk(const struct pcpu_alloc_info *ai, 99 void *base_addr); 100 101 #ifdef CONFIG_NEED_PER_CPU_EMBED_FIRST_CHUNK 102 extern int __init pcpu_embed_first_chunk(size_t reserved_size, size_t dyn_size, 103 size_t atom_size, 104 pcpu_fc_cpu_distance_fn_t cpu_distance_fn, 105 pcpu_fc_alloc_fn_t alloc_fn, 106 pcpu_fc_free_fn_t free_fn); 107 #endif 108 109 #ifdef CONFIG_NEED_PER_CPU_PAGE_FIRST_CHUNK 110 extern int __init pcpu_page_first_chunk(size_t reserved_size, 111 pcpu_fc_alloc_fn_t alloc_fn, 112 pcpu_fc_free_fn_t free_fn, 113 pcpu_fc_populate_pte_fn_t populate_pte_fn); 114 #endif 115 116 extern void __percpu *__alloc_reserved_percpu(size_t size, size_t align); 117 extern bool __is_kernel_percpu_address(unsigned long addr, unsigned long *can_addr); 118 extern bool is_kernel_percpu_address(unsigned long addr); 119 120 #if !defined(CONFIG_SMP) || !defined(CONFIG_HAVE_SETUP_PER_CPU_AREA) 121 extern void __init setup_per_cpu_areas(void); 122 #endif 123 124 extern void __percpu *__alloc_percpu_gfp(size_t size, size_t align, gfp_t gfp); 125 extern void __percpu *__alloc_percpu(size_t size, size_t align); 126 extern void free_percpu(void __percpu *__pdata); 127 extern phys_addr_t per_cpu_ptr_to_phys(void *addr); 128 129 #define alloc_percpu_gfp(type, gfp) \ 130 (typeof(type) __percpu *)__alloc_percpu_gfp(sizeof(type), \ 131 __alignof__(type), gfp) 132 #define alloc_percpu(type) \ 133 (typeof(type) __percpu *)__alloc_percpu(sizeof(type), \ 134 __alignof__(type)) 135 136 #endif /* __LINUX_PERCPU_H */ 137