Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | #ifndef __LINUX_PERCPU_H |
| 2 | #define __LINUX_PERCPU_H |
Martin Peschke | 7ff6f08 | 2006-09-25 23:31:21 -0700 | [diff] [blame] | 3 | |
Robert P. J. Day | 0a3021f | 2007-07-15 23:39:57 -0700 | [diff] [blame] | 4 | #include <linux/preempt.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 5 | #include <linux/slab.h> /* For kmalloc() */ |
| 6 | #include <linux/smp.h> |
Martin Peschke | 7ff6f08 | 2006-09-25 23:31:21 -0700 | [diff] [blame] | 7 | #include <linux/cpumask.h> |
Tejun Heo | 6a24290 | 2009-03-06 14:33:58 +0900 | [diff] [blame] | 8 | #include <linux/pfn.h> |
Martin Peschke | 7ff6f08 | 2006-09-25 23:31:21 -0700 | [diff] [blame] | 9 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 10 | #include <asm/percpu.h> |
| 11 | |
Brian Gerst | d377044 | 2009-02-08 09:58:38 -0500 | [diff] [blame] | 12 | #ifndef PER_CPU_BASE_SECTION |
travis@sgi.com | 5280e00 | 2008-01-30 13:32:52 +0100 | [diff] [blame] | 13 | #ifdef CONFIG_SMP |
Brian Gerst | 0bd74fa | 2009-01-19 12:21:27 +0900 | [diff] [blame] | 14 | #define PER_CPU_BASE_SECTION ".data.percpu" |
Brian Gerst | d377044 | 2009-02-08 09:58:38 -0500 | [diff] [blame] | 15 | #else |
| 16 | #define PER_CPU_BASE_SECTION ".data" |
| 17 | #endif |
| 18 | #endif |
| 19 | |
| 20 | #ifdef CONFIG_SMP |
travis@sgi.com | 5280e00 | 2008-01-30 13:32:52 +0100 | [diff] [blame] | 21 | |
Eric Dumazet | 44c8143 | 2008-05-14 16:05:51 -0700 | [diff] [blame] | 22 | #ifdef MODULE |
Brian Gerst | 0bd74fa | 2009-01-19 12:21:27 +0900 | [diff] [blame] | 23 | #define PER_CPU_SHARED_ALIGNED_SECTION "" |
Eric Dumazet | 44c8143 | 2008-05-14 16:05:51 -0700 | [diff] [blame] | 24 | #else |
Brian Gerst | 0bd74fa | 2009-01-19 12:21:27 +0900 | [diff] [blame] | 25 | #define PER_CPU_SHARED_ALIGNED_SECTION ".shared_aligned" |
Eric Dumazet | 44c8143 | 2008-05-14 16:05:51 -0700 | [diff] [blame] | 26 | #endif |
Brian Gerst | 0bd74fa | 2009-01-19 12:21:27 +0900 | [diff] [blame] | 27 | #define PER_CPU_FIRST_SECTION ".first" |
| 28 | |
| 29 | #else |
| 30 | |
Brian Gerst | 0bd74fa | 2009-01-19 12:21:27 +0900 | [diff] [blame] | 31 | #define PER_CPU_SHARED_ALIGNED_SECTION "" |
| 32 | #define PER_CPU_FIRST_SECTION "" |
| 33 | |
| 34 | #endif |
| 35 | |
| 36 | #define DEFINE_PER_CPU_SECTION(type, name, section) \ |
| 37 | __attribute__((__section__(PER_CPU_BASE_SECTION section))) \ |
| 38 | PER_CPU_ATTRIBUTES __typeof__(type) per_cpu__##name |
| 39 | |
| 40 | #define DEFINE_PER_CPU(type, name) \ |
| 41 | DEFINE_PER_CPU_SECTION(type, name, "") |
Eric Dumazet | 44c8143 | 2008-05-14 16:05:51 -0700 | [diff] [blame] | 42 | |
travis@sgi.com | 5280e00 | 2008-01-30 13:32:52 +0100 | [diff] [blame] | 43 | #define DEFINE_PER_CPU_SHARED_ALIGNED(type, name) \ |
Brian Gerst | 0bd74fa | 2009-01-19 12:21:27 +0900 | [diff] [blame] | 44 | DEFINE_PER_CPU_SECTION(type, name, PER_CPU_SHARED_ALIGNED_SECTION) \ |
travis@sgi.com | 5280e00 | 2008-01-30 13:32:52 +0100 | [diff] [blame] | 45 | ____cacheline_aligned_in_smp |
Eric Dumazet | 63cc8c7 | 2008-05-12 15:44:40 +0200 | [diff] [blame] | 46 | |
Brian Gerst | 0bd74fa | 2009-01-19 12:21:27 +0900 | [diff] [blame] | 47 | #define DEFINE_PER_CPU_PAGE_ALIGNED(type, name) \ |
| 48 | DEFINE_PER_CPU_SECTION(type, name, ".page_aligned") |
travis@sgi.com | 5280e00 | 2008-01-30 13:32:52 +0100 | [diff] [blame] | 49 | |
Brian Gerst | 0bd74fa | 2009-01-19 12:21:27 +0900 | [diff] [blame] | 50 | #define DEFINE_PER_CPU_FIRST(type, name) \ |
| 51 | DEFINE_PER_CPU_SECTION(type, name, PER_CPU_FIRST_SECTION) |
travis@sgi.com | 5280e00 | 2008-01-30 13:32:52 +0100 | [diff] [blame] | 52 | |
| 53 | #define EXPORT_PER_CPU_SYMBOL(var) EXPORT_SYMBOL(per_cpu__##var) |
| 54 | #define EXPORT_PER_CPU_SYMBOL_GPL(var) EXPORT_SYMBOL_GPL(per_cpu__##var) |
| 55 | |
Tejun Heo | 6a24290 | 2009-03-06 14:33:58 +0900 | [diff] [blame] | 56 | /* enough to cover all DEFINE_PER_CPUs in modules */ |
Jeremy Fitzhardinge | b00742d3 | 2007-05-02 19:27:11 +0200 | [diff] [blame] | 57 | #ifdef CONFIG_MODULES |
Tejun Heo | 6a24290 | 2009-03-06 14:33:58 +0900 | [diff] [blame] | 58 | #define PERCPU_MODULE_RESERVE (8 << 10) |
Jeremy Fitzhardinge | b00742d3 | 2007-05-02 19:27:11 +0200 | [diff] [blame] | 59 | #else |
Tejun Heo | 6a24290 | 2009-03-06 14:33:58 +0900 | [diff] [blame] | 60 | #define PERCPU_MODULE_RESERVE 0 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 61 | #endif |
| 62 | |
Tejun Heo | 6a24290 | 2009-03-06 14:33:58 +0900 | [diff] [blame] | 63 | #ifndef PERCPU_ENOUGH_ROOM |
Jeremy Fitzhardinge | b00742d3 | 2007-05-02 19:27:11 +0200 | [diff] [blame] | 64 | #define PERCPU_ENOUGH_ROOM \ |
Tejun Heo | 6a24290 | 2009-03-06 14:33:58 +0900 | [diff] [blame] | 65 | (ALIGN(__per_cpu_end - __per_cpu_start, SMP_CACHE_BYTES) + \ |
| 66 | PERCPU_MODULE_RESERVE) |
| 67 | #endif |
Jeremy Fitzhardinge | b00742d3 | 2007-05-02 19:27:11 +0200 | [diff] [blame] | 68 | |
Jan Blunck | 632bbfe | 2006-09-25 23:30:53 -0700 | [diff] [blame] | 69 | /* |
| 70 | * Must be an lvalue. Since @var must be a simple identifier, |
| 71 | * we force a syntax error here if it isn't. |
| 72 | */ |
| 73 | #define get_cpu_var(var) (*({ \ |
Jan Blunck | a666ecf | 2006-10-06 00:43:58 -0700 | [diff] [blame] | 74 | extern int simple_identifier_##var(void); \ |
Jan Blunck | 632bbfe | 2006-09-25 23:30:53 -0700 | [diff] [blame] | 75 | preempt_disable(); \ |
| 76 | &__get_cpu_var(var); })) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 77 | #define put_cpu_var(var) preempt_enable() |
| 78 | |
| 79 | #ifdef CONFIG_SMP |
| 80 | |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 81 | #ifdef CONFIG_HAVE_DYNAMIC_PER_CPU_AREA |
| 82 | |
Tejun Heo | 8d408b4 | 2009-02-24 11:57:21 +0900 | [diff] [blame] | 83 | /* minimum unit size, also is the maximum supported allocation size */ |
Tejun Heo | 6a24290 | 2009-03-06 14:33:58 +0900 | [diff] [blame] | 84 | #define PCPU_MIN_UNIT_SIZE PFN_ALIGN(64 << 10) |
Tejun Heo | 8d408b4 | 2009-02-24 11:57:21 +0900 | [diff] [blame] | 85 | |
| 86 | /* |
| 87 | * PERCPU_DYNAMIC_RESERVE indicates the amount of free area to piggy |
Tejun Heo | 6b19b0c | 2009-03-06 14:33:59 +0900 | [diff] [blame] | 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). |
Tejun Heo | 8d408b4 | 2009-02-24 11:57:21 +0900 | [diff] [blame] | 91 | * |
Tejun Heo | 6b19b0c | 2009-03-06 14:33:59 +0900 | [diff] [blame] | 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. |
Tejun Heo | 8d408b4 | 2009-02-24 11:57:21 +0900 | [diff] [blame] | 96 | */ |
Tejun Heo | 6b19b0c | 2009-03-06 14:33:59 +0900 | [diff] [blame] | 97 | #if BITS_PER_LONG > 32 |
| 98 | #define PERCPU_DYNAMIC_RESERVE (20 << 10) |
| 99 | #else |
| 100 | #define PERCPU_DYNAMIC_RESERVE (12 << 10) |
| 101 | #endif |
Tejun Heo | 8d408b4 | 2009-02-24 11:57:21 +0900 | [diff] [blame] | 102 | |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 103 | extern void *pcpu_base_addr; |
| 104 | |
Tejun Heo | 8d408b4 | 2009-02-24 11:57:21 +0900 | [diff] [blame] | 105 | typedef struct page * (*pcpu_get_page_fn_t)(unsigned int cpu, int pageno); |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 106 | typedef void (*pcpu_populate_pte_fn_t)(unsigned long addr); |
| 107 | |
Tejun Heo | 8d408b4 | 2009-02-24 11:57:21 +0900 | [diff] [blame] | 108 | extern size_t __init pcpu_setup_first_chunk(pcpu_get_page_fn_t get_page_fn, |
Tejun Heo | edcb463 | 2009-03-06 14:33:59 +0900 | [diff] [blame] | 109 | size_t static_size, size_t reserved_size, |
Tejun Heo | 6074d5b | 2009-03-10 16:27:48 +0900 | [diff] [blame] | 110 | ssize_t dyn_size, ssize_t unit_size, |
Tejun Heo | edcb463 | 2009-03-06 14:33:59 +0900 | [diff] [blame] | 111 | void *base_addr, |
| 112 | pcpu_populate_pte_fn_t populate_pte_fn); |
Tejun Heo | 8d408b4 | 2009-02-24 11:57:21 +0900 | [diff] [blame] | 113 | |
Tejun Heo | 66c3a75 | 2009-03-10 16:27:48 +0900 | [diff] [blame] | 114 | extern ssize_t __init pcpu_embed_first_chunk( |
| 115 | size_t static_size, size_t reserved_size, |
| 116 | ssize_t dyn_size, ssize_t unit_size); |
| 117 | |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 118 | /* |
| 119 | * Use this to get to a cpu's version of the per-cpu object |
| 120 | * dynamically allocated. Non-atomic access to the current CPU's |
| 121 | * version should probably be combined with get_cpu()/put_cpu(). |
| 122 | */ |
| 123 | #define per_cpu_ptr(ptr, cpu) SHIFT_PERCPU_PTR((ptr), per_cpu_offset((cpu))) |
| 124 | |
Tejun Heo | edcb463 | 2009-03-06 14:33:59 +0900 | [diff] [blame] | 125 | extern void *__alloc_reserved_percpu(size_t size, size_t align); |
| 126 | |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 127 | #else /* CONFIG_HAVE_DYNAMIC_PER_CPU_AREA */ |
| 128 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 129 | struct percpu_data { |
Eric Dumazet | b324215 | 2008-02-06 01:37:01 -0800 | [diff] [blame] | 130 | void *ptrs[1]; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 131 | }; |
| 132 | |
Martin Peschke | 7ff6f08 | 2006-09-25 23:31:21 -0700 | [diff] [blame] | 133 | #define __percpu_disguise(pdata) (struct percpu_data *)~(unsigned long)(pdata) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 134 | |
Rusty Russell | b36128c | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 135 | #define per_cpu_ptr(ptr, cpu) \ |
| 136 | ({ \ |
| 137 | struct percpu_data *__p = __percpu_disguise(ptr); \ |
| 138 | (__typeof__(ptr))__p->ptrs[(cpu)]; \ |
| 139 | }) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 140 | |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 141 | #endif /* CONFIG_HAVE_DYNAMIC_PER_CPU_AREA */ |
| 142 | |
Tejun Heo | f2a8205 | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 143 | extern void *__alloc_percpu(size_t size, size_t align); |
| 144 | extern void free_percpu(void *__pdata); |
| 145 | |
| 146 | #else /* CONFIG_SMP */ |
| 147 | |
| 148 | #define per_cpu_ptr(ptr, cpu) ({ (void)(cpu); (ptr); }) |
| 149 | |
| 150 | static inline void *__alloc_percpu(size_t size, size_t align) |
| 151 | { |
| 152 | /* |
| 153 | * Can't easily make larger alignment work with kmalloc. WARN |
| 154 | * on it. Larger alignment should only be used for module |
| 155 | * percpu sections on SMP for which this path isn't used. |
| 156 | */ |
Tejun Heo | e317603 | 2009-02-26 10:54:17 +0900 | [diff] [blame] | 157 | WARN_ON_ONCE(align > SMP_CACHE_BYTES); |
Ingo Molnar | d2b0261 | 2009-02-25 14:36:45 +0100 | [diff] [blame] | 158 | return kzalloc(size, GFP_KERNEL); |
Tejun Heo | f2a8205 | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 159 | } |
| 160 | |
| 161 | static inline void free_percpu(void *p) |
| 162 | { |
| 163 | kfree(p); |
| 164 | } |
| 165 | |
| 166 | #endif /* CONFIG_SMP */ |
| 167 | |
| 168 | #define alloc_percpu(type) (type *)__alloc_percpu(sizeof(type), \ |
| 169 | __alignof__(type)) |
| 170 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 171 | #endif /* __LINUX_PERCPU_H */ |