Merge branch 'misc' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild
[firefly-linux-kernel-4.4.55.git] / include / linux / percpu.h
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 #ifndef PERCPU_ENOUGH_ROOM
22 #define PERCPU_ENOUGH_ROOM                                              \
23         (ALIGN(__per_cpu_end - __per_cpu_start, SMP_CACHE_BYTES) +      \
24          PERCPU_MODULE_RESERVE)
25 #endif
26
27 /* minimum unit size, also is the maximum supported allocation size */
28 #define PCPU_MIN_UNIT_SIZE              PFN_ALIGN(32 << 10)
29
30 /*
31  * Percpu allocator can serve percpu allocations before slab is
32  * initialized which allows slab to depend on the percpu allocator.
33  * The following two parameters decide how much resource to
34  * preallocate for this.  Keep PERCPU_DYNAMIC_RESERVE equal to or
35  * larger than PERCPU_DYNAMIC_EARLY_SIZE.
36  */
37 #define PERCPU_DYNAMIC_EARLY_SLOTS      128
38 #define PERCPU_DYNAMIC_EARLY_SIZE       (12 << 10)
39
40 /*
41  * PERCPU_DYNAMIC_RESERVE indicates the amount of free area to piggy
42  * back on the first chunk for dynamic percpu allocation if arch is
43  * manually allocating and mapping it for faster access (as a part of
44  * large page mapping for example).
45  *
46  * The following values give between one and two pages of free space
47  * after typical minimal boot (2-way SMP, single disk and NIC) with
48  * both defconfig and a distro config on x86_64 and 32.  More
49  * intelligent way to determine this would be nice.
50  */
51 #if BITS_PER_LONG > 32
52 #define PERCPU_DYNAMIC_RESERVE          (28 << 10)
53 #else
54 #define PERCPU_DYNAMIC_RESERVE          (20 << 10)
55 #endif
56
57 extern void *pcpu_base_addr;
58 extern const unsigned long *pcpu_unit_offsets;
59
60 struct pcpu_group_info {
61         int                     nr_units;       /* aligned # of units */
62         unsigned long           base_offset;    /* base address offset */
63         unsigned int            *cpu_map;       /* unit->cpu map, empty
64                                                  * entries contain NR_CPUS */
65 };
66
67 struct pcpu_alloc_info {
68         size_t                  static_size;
69         size_t                  reserved_size;
70         size_t                  dyn_size;
71         size_t                  unit_size;
72         size_t                  atom_size;
73         size_t                  alloc_size;
74         size_t                  __ai_size;      /* internal, don't use */
75         int                     nr_groups;      /* 0 if grouping unnecessary */
76         struct pcpu_group_info  groups[];
77 };
78
79 enum pcpu_fc {
80         PCPU_FC_AUTO,
81         PCPU_FC_EMBED,
82         PCPU_FC_PAGE,
83
84         PCPU_FC_NR,
85 };
86 extern const char * const pcpu_fc_names[PCPU_FC_NR];
87
88 extern enum pcpu_fc pcpu_chosen_fc;
89
90 typedef void * (*pcpu_fc_alloc_fn_t)(unsigned int cpu, size_t size,
91                                      size_t align);
92 typedef void (*pcpu_fc_free_fn_t)(void *ptr, size_t size);
93 typedef void (*pcpu_fc_populate_pte_fn_t)(unsigned long addr);
94 typedef int (pcpu_fc_cpu_distance_fn_t)(unsigned int from, unsigned int to);
95
96 extern struct pcpu_alloc_info * __init pcpu_alloc_alloc_info(int nr_groups,
97                                                              int nr_units);
98 extern void __init pcpu_free_alloc_info(struct pcpu_alloc_info *ai);
99
100 extern int __init pcpu_setup_first_chunk(const struct pcpu_alloc_info *ai,
101                                          void *base_addr);
102
103 #ifdef CONFIG_NEED_PER_CPU_EMBED_FIRST_CHUNK
104 extern int __init pcpu_embed_first_chunk(size_t reserved_size, size_t dyn_size,
105                                 size_t atom_size,
106                                 pcpu_fc_cpu_distance_fn_t cpu_distance_fn,
107                                 pcpu_fc_alloc_fn_t alloc_fn,
108                                 pcpu_fc_free_fn_t free_fn);
109 #endif
110
111 #ifdef CONFIG_NEED_PER_CPU_PAGE_FIRST_CHUNK
112 extern int __init pcpu_page_first_chunk(size_t reserved_size,
113                                 pcpu_fc_alloc_fn_t alloc_fn,
114                                 pcpu_fc_free_fn_t free_fn,
115                                 pcpu_fc_populate_pte_fn_t populate_pte_fn);
116 #endif
117
118 extern void __percpu *__alloc_reserved_percpu(size_t size, size_t align);
119 extern bool is_kernel_percpu_address(unsigned long addr);
120
121 #if !defined(CONFIG_SMP) || !defined(CONFIG_HAVE_SETUP_PER_CPU_AREA)
122 extern void __init setup_per_cpu_areas(void);
123 #endif
124 extern void __init percpu_init_late(void);
125
126 extern void __percpu *__alloc_percpu_gfp(size_t size, size_t align, gfp_t gfp);
127 extern void __percpu *__alloc_percpu(size_t size, size_t align);
128 extern void free_percpu(void __percpu *__pdata);
129 extern phys_addr_t per_cpu_ptr_to_phys(void *addr);
130
131 #define alloc_percpu_gfp(type, gfp)                                     \
132         (typeof(type) __percpu *)__alloc_percpu_gfp(sizeof(type),       \
133                                                 __alignof__(type), gfp)
134 #define alloc_percpu(type)                                              \
135         (typeof(type) __percpu *)__alloc_percpu(sizeof(type),           \
136                                                 __alignof__(type))
137
138 /* To avoid include hell, as printk can not declare this, we declare it here */
139 DECLARE_PER_CPU(printk_func_t, printk_func);
140
141 #endif /* __LINUX_PERCPU_H */