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/pfn.h> 9 #include <linux/init.h> 10 11 #include <asm/percpu.h> 12 13 /* enough to cover all DEFINE_PER_CPUs in modules */ 14 #ifdef CONFIG_MODULES 15 #define PERCPU_MODULE_RESERVE (8 << 10) 16 #else 17 #define PERCPU_MODULE_RESERVE 0 18 #endif 19 20 #ifndef PERCPU_ENOUGH_ROOM 21 #define PERCPU_ENOUGH_ROOM \ 22 (ALIGN(__per_cpu_end - __per_cpu_start, SMP_CACHE_BYTES) + \ 23 PERCPU_MODULE_RESERVE) 24 #endif 25 26 /* minimum unit size, also is the maximum supported allocation size */ 27 #define PCPU_MIN_UNIT_SIZE PFN_ALIGN(32 << 10) 28 29 /* 30 * Percpu allocator can serve percpu allocations before slab is 31 * initialized which allows slab to depend on the percpu allocator. 32 * The following two parameters decide how much resource to 33 * preallocate for this. Keep PERCPU_DYNAMIC_RESERVE equal to or 34 * larger than PERCPU_DYNAMIC_EARLY_SIZE. 35 */ 36 #define PERCPU_DYNAMIC_EARLY_SLOTS 128 37 #define PERCPU_DYNAMIC_EARLY_SIZE (12 << 10) 38 39 /* 40 * PERCPU_DYNAMIC_RESERVE indicates the amount of free area to piggy 41 * back on the first chunk for dynamic percpu allocation if arch is 42 * manually allocating and mapping it for faster access (as a part of 43 * large page mapping for example). 44 * 45 * The following values give between one and two pages of free space 46 * after typical minimal boot (2-way SMP, single disk and NIC) with 47 * both defconfig and a distro config on x86_64 and 32. More 48 * intelligent way to determine this would be nice. 49 */ 50 #if BITS_PER_LONG > 32 51 #define PERCPU_DYNAMIC_RESERVE (28 << 10) 52 #else 53 #define PERCPU_DYNAMIC_RESERVE (20 << 10) 54 #endif 55 56 extern void *pcpu_base_addr; 57 extern const unsigned long *pcpu_unit_offsets; 58 59 struct pcpu_group_info { 60 int nr_units; /* aligned # of units */ 61 unsigned long base_offset; /* base address offset */ 62 unsigned int *cpu_map; /* unit->cpu map, empty 63 * entries contain NR_CPUS */ 64 }; 65 66 struct pcpu_alloc_info { 67 size_t static_size; 68 size_t reserved_size; 69 size_t dyn_size; 70 size_t unit_size; 71 size_t atom_size; 72 size_t alloc_size; 73 size_t __ai_size; /* internal, don't use */ 74 int nr_groups; /* 0 if grouping unnecessary */ 75 struct pcpu_group_info groups[]; 76 }; 77 78 enum pcpu_fc { 79 PCPU_FC_AUTO, 80 PCPU_FC_EMBED, 81 PCPU_FC_PAGE, 82 83 PCPU_FC_NR, 84 }; 85 extern const char * const pcpu_fc_names[PCPU_FC_NR]; 86 87 extern enum pcpu_fc pcpu_chosen_fc; 88 89 typedef void * (*pcpu_fc_alloc_fn_t)(unsigned int cpu, size_t size, 90 size_t align); 91 typedef void (*pcpu_fc_free_fn_t)(void *ptr, size_t size); 92 typedef void (*pcpu_fc_populate_pte_fn_t)(unsigned long addr); 93 typedef int (pcpu_fc_cpu_distance_fn_t)(unsigned int from, unsigned int to); 94 95 extern struct pcpu_alloc_info * __init pcpu_alloc_alloc_info(int nr_groups, 96 int nr_units); 97 extern void __init pcpu_free_alloc_info(struct pcpu_alloc_info *ai); 98 99 extern int __init pcpu_setup_first_chunk(const struct pcpu_alloc_info *ai, 100 void *base_addr); 101 102 #ifdef CONFIG_NEED_PER_CPU_EMBED_FIRST_CHUNK 103 extern int __init pcpu_embed_first_chunk(size_t reserved_size, size_t dyn_size, 104 size_t atom_size, 105 pcpu_fc_cpu_distance_fn_t cpu_distance_fn, 106 pcpu_fc_alloc_fn_t alloc_fn, 107 pcpu_fc_free_fn_t free_fn); 108 #endif 109 110 #ifdef CONFIG_NEED_PER_CPU_PAGE_FIRST_CHUNK 111 extern int __init pcpu_page_first_chunk(size_t reserved_size, 112 pcpu_fc_alloc_fn_t alloc_fn, 113 pcpu_fc_free_fn_t free_fn, 114 pcpu_fc_populate_pte_fn_t populate_pte_fn); 115 #endif 116 117 extern void __percpu *__alloc_reserved_percpu(size_t size, size_t align); 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 extern void __init percpu_init_late(void); 124 125 extern void __percpu *__alloc_percpu_gfp(size_t size, size_t align, gfp_t gfp); 126 extern void __percpu *__alloc_percpu(size_t size, size_t align); 127 extern void free_percpu(void __percpu *__pdata); 128 extern phys_addr_t per_cpu_ptr_to_phys(void *addr); 129 130 #define alloc_percpu_gfp(type, gfp) \ 131 (typeof(type) __percpu *)__alloc_percpu_gfp(sizeof(type), \ 132 __alignof__(type), gfp) 133 #define alloc_percpu(type) \ 134 (typeof(type) __percpu *)__alloc_percpu(sizeof(type), \ 135 __alignof__(type)) 136 137 #endif /* __LINUX_PERCPU_H */ 138