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-rw-r--r--include/linux/percpu.h108
1 files changed, 74 insertions, 34 deletions
diff --git a/include/linux/percpu.h b/include/linux/percpu.h
index 3577ffd90d45..54a968b4b924 100644
--- a/include/linux/percpu.h
+++ b/include/linux/percpu.h
@@ -5,6 +5,7 @@
5#include <linux/slab.h> /* For kmalloc() */ 5#include <linux/slab.h> /* For kmalloc() */
6#include <linux/smp.h> 6#include <linux/smp.h>
7#include <linux/cpumask.h> 7#include <linux/cpumask.h>
8#include <linux/pfn.h>
8 9
9#include <asm/percpu.h> 10#include <asm/percpu.h>
10 11
@@ -52,17 +53,18 @@
52#define EXPORT_PER_CPU_SYMBOL(var) EXPORT_SYMBOL(per_cpu__##var) 53#define EXPORT_PER_CPU_SYMBOL(var) EXPORT_SYMBOL(per_cpu__##var)
53#define EXPORT_PER_CPU_SYMBOL_GPL(var) EXPORT_SYMBOL_GPL(per_cpu__##var) 54#define EXPORT_PER_CPU_SYMBOL_GPL(var) EXPORT_SYMBOL_GPL(per_cpu__##var)
54 55
55/* Enough to cover all DEFINE_PER_CPUs in kernel, including modules. */ 56/* enough to cover all DEFINE_PER_CPUs in modules */
56#ifndef PERCPU_ENOUGH_ROOM
57#ifdef CONFIG_MODULES 57#ifdef CONFIG_MODULES
58#define PERCPU_MODULE_RESERVE 8192 58#define PERCPU_MODULE_RESERVE (8 << 10)
59#else 59#else
60#define PERCPU_MODULE_RESERVE 0 60#define PERCPU_MODULE_RESERVE 0
61#endif 61#endif
62 62
63#ifndef PERCPU_ENOUGH_ROOM
63#define PERCPU_ENOUGH_ROOM \ 64#define PERCPU_ENOUGH_ROOM \
64 (__per_cpu_end - __per_cpu_start + PERCPU_MODULE_RESERVE) 65 (ALIGN(__per_cpu_end - __per_cpu_start, SMP_CACHE_BYTES) + \
65#endif /* PERCPU_ENOUGH_ROOM */ 66 PERCPU_MODULE_RESERVE)
67#endif
66 68
67/* 69/*
68 * Must be an lvalue. Since @var must be a simple identifier, 70 * Must be an lvalue. Since @var must be a simple identifier,
@@ -76,52 +78,90 @@
76 78
77#ifdef CONFIG_SMP 79#ifdef CONFIG_SMP
78 80
81#ifdef CONFIG_HAVE_DYNAMIC_PER_CPU_AREA
82
83/* minimum unit size, also is the maximum supported allocation size */
84#define PCPU_MIN_UNIT_SIZE PFN_ALIGN(64 << 10)
85
86/*
87 * PERCPU_DYNAMIC_RESERVE indicates the amount of free area to piggy
88 * back on the first chunk for dynamic percpu allocation if arch is
89 * manually allocating and mapping it for faster access (as a part of
90 * large page mapping for example).
91 *
92 * The following values give between one and two pages of free space
93 * after typical minimal boot (2-way SMP, single disk and NIC) with
94 * both defconfig and a distro config on x86_64 and 32. More
95 * intelligent way to determine this would be nice.
96 */
97#if BITS_PER_LONG > 32
98#define PERCPU_DYNAMIC_RESERVE (20 << 10)
99#else
100#define PERCPU_DYNAMIC_RESERVE (12 << 10)
101#endif
102
103extern void *pcpu_base_addr;
104
105typedef struct page * (*pcpu_get_page_fn_t)(unsigned int cpu, int pageno);
106typedef void (*pcpu_populate_pte_fn_t)(unsigned long addr);
107
108extern size_t __init pcpu_setup_first_chunk(pcpu_get_page_fn_t get_page_fn,
109 size_t static_size, size_t reserved_size,
110 ssize_t unit_size, ssize_t dyn_size,
111 void *base_addr,
112 pcpu_populate_pte_fn_t populate_pte_fn);
113
114/*
115 * Use this to get to a cpu's version of the per-cpu object
116 * dynamically allocated. Non-atomic access to the current CPU's
117 * version should probably be combined with get_cpu()/put_cpu().
118 */
119#define per_cpu_ptr(ptr, cpu) SHIFT_PERCPU_PTR((ptr), per_cpu_offset((cpu)))
120
121extern void *__alloc_reserved_percpu(size_t size, size_t align);
122
123#else /* CONFIG_HAVE_DYNAMIC_PER_CPU_AREA */
124
79struct percpu_data { 125struct percpu_data {
80 void *ptrs[1]; 126 void *ptrs[1];
81}; 127};
82 128
83#define __percpu_disguise(pdata) (struct percpu_data *)~(unsigned long)(pdata) 129#define __percpu_disguise(pdata) (struct percpu_data *)~(unsigned long)(pdata)
84/* 130
85 * Use this to get to a cpu's version of the per-cpu object dynamically 131#define per_cpu_ptr(ptr, cpu) \
86 * allocated. Non-atomic access to the current CPU's version should 132({ \
87 * probably be combined with get_cpu()/put_cpu(). 133 struct percpu_data *__p = __percpu_disguise(ptr); \
88 */ 134 (__typeof__(ptr))__p->ptrs[(cpu)]; \
89#define percpu_ptr(ptr, cpu) \
90({ \
91 struct percpu_data *__p = __percpu_disguise(ptr); \
92 (__typeof__(ptr))__p->ptrs[(cpu)]; \
93}) 135})
94 136
95extern void *__percpu_alloc_mask(size_t size, gfp_t gfp, cpumask_t *mask); 137#endif /* CONFIG_HAVE_DYNAMIC_PER_CPU_AREA */
96extern void percpu_free(void *__pdata); 138
139extern void *__alloc_percpu(size_t size, size_t align);
140extern void free_percpu(void *__pdata);
97 141
98#else /* CONFIG_SMP */ 142#else /* CONFIG_SMP */
99 143
100#define percpu_ptr(ptr, cpu) ({ (void)(cpu); (ptr); }) 144#define per_cpu_ptr(ptr, cpu) ({ (void)(cpu); (ptr); })
101 145
102static __always_inline void *__percpu_alloc_mask(size_t size, gfp_t gfp, cpumask_t *mask) 146static inline void *__alloc_percpu(size_t size, size_t align)
103{ 147{
104 return kzalloc(size, gfp); 148 /*
149 * Can't easily make larger alignment work with kmalloc. WARN
150 * on it. Larger alignment should only be used for module
151 * percpu sections on SMP for which this path isn't used.
152 */
153 WARN_ON_ONCE(align > SMP_CACHE_BYTES);
154 return kzalloc(size, GFP_KERNEL);
105} 155}
106 156
107static inline void percpu_free(void *__pdata) 157static inline void free_percpu(void *p)
108{ 158{
109 kfree(__pdata); 159 kfree(p);
110} 160}
111 161
112#endif /* CONFIG_SMP */ 162#endif /* CONFIG_SMP */
113 163
114#define percpu_alloc_mask(size, gfp, mask) \ 164#define alloc_percpu(type) (type *)__alloc_percpu(sizeof(type), \
115 __percpu_alloc_mask((size), (gfp), &(mask)) 165 __alignof__(type))
116
117#define percpu_alloc(size, gfp) percpu_alloc_mask((size), (gfp), cpu_online_map)
118
119/* (legacy) interface for use without CPU hotplug handling */
120
121#define __alloc_percpu(size) percpu_alloc_mask((size), GFP_KERNEL, \
122 cpu_possible_map)
123#define alloc_percpu(type) (type *)__alloc_percpu(sizeof(type))
124#define free_percpu(ptr) percpu_free((ptr))
125#define per_cpu_ptr(ptr, cpu) percpu_ptr((ptr), (cpu))
126 166
127#endif /* __LINUX_PERCPU_H */ 167#endif /* __LINUX_PERCPU_H */