Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 1 | /* |
| 2 | * linux/mm/percpu.c - percpu memory allocator |
| 3 | * |
| 4 | * Copyright (C) 2009 SUSE Linux Products GmbH |
| 5 | * Copyright (C) 2009 Tejun Heo <tj@kernel.org> |
| 6 | * |
| 7 | * This file is released under the GPLv2. |
| 8 | * |
| 9 | * This is percpu allocator which can handle both static and dynamic |
| 10 | * areas. Percpu areas are allocated in chunks in vmalloc area. Each |
Tejun Heo | 2f39e63 | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 11 | * chunk is consisted of boot-time determined number of units and the |
| 12 | * first chunk is used for static percpu variables in the kernel image |
| 13 | * (special boot time alloc/init handling necessary as these areas |
| 14 | * need to be brought up before allocation services are running). |
| 15 | * Unit grows as necessary and all units grow or shrink in unison. |
| 16 | * When a chunk is filled up, another chunk is allocated. ie. in |
| 17 | * vmalloc area |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 18 | * |
| 19 | * c0 c1 c2 |
| 20 | * ------------------- ------------------- ------------ |
| 21 | * | u0 | u1 | u2 | u3 | | u0 | u1 | u2 | u3 | | u0 | u1 | u |
| 22 | * ------------------- ...... ------------------- .... ------------ |
| 23 | * |
| 24 | * Allocation is done in offset-size areas of single unit space. Ie, |
| 25 | * an area of 512 bytes at 6k in c1 occupies 512 bytes at 6k of c1:u0, |
Tejun Heo | 2f39e63 | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 26 | * c1:u1, c1:u2 and c1:u3. On UMA, units corresponds directly to |
| 27 | * cpus. On NUMA, the mapping can be non-linear and even sparse. |
| 28 | * Percpu access can be done by configuring percpu base registers |
| 29 | * according to cpu to unit mapping and pcpu_unit_size. |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 30 | * |
Tejun Heo | 2f39e63 | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 31 | * There are usually many small percpu allocations many of them being |
| 32 | * as small as 4 bytes. The allocator organizes chunks into lists |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 33 | * according to free size and tries to allocate from the fullest one. |
| 34 | * Each chunk keeps the maximum contiguous area size hint which is |
| 35 | * guaranteed to be eqaul to or larger than the maximum contiguous |
| 36 | * area in the chunk. This helps the allocator not to iterate the |
| 37 | * chunk maps unnecessarily. |
| 38 | * |
| 39 | * Allocation state in each chunk is kept using an array of integers |
| 40 | * on chunk->map. A positive value in the map represents a free |
| 41 | * region and negative allocated. Allocation inside a chunk is done |
| 42 | * by scanning this map sequentially and serving the first matching |
| 43 | * entry. This is mostly copied from the percpu_modalloc() allocator. |
Christoph Lameter | e1b9aa3 | 2009-04-02 13:21:44 +0900 | [diff] [blame] | 44 | * Chunks can be determined from the address using the index field |
| 45 | * in the page struct. The index field contains a pointer to the chunk. |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 46 | * |
| 47 | * To use this allocator, arch code should do the followings. |
| 48 | * |
Tejun Heo | e74e396 | 2009-03-30 19:07:44 +0900 | [diff] [blame] | 49 | * - drop CONFIG_HAVE_LEGACY_PER_CPU_AREA |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 50 | * |
| 51 | * - define __addr_to_pcpu_ptr() and __pcpu_ptr_to_addr() to translate |
Tejun Heo | e010098 | 2009-03-10 16:27:48 +0900 | [diff] [blame] | 52 | * regular address to percpu pointer and back if they need to be |
| 53 | * different from the default |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 54 | * |
Tejun Heo | 8d408b4 | 2009-02-24 11:57:21 +0900 | [diff] [blame] | 55 | * - use pcpu_setup_first_chunk() during percpu area initialization to |
| 56 | * setup the first chunk containing the kernel static percpu area |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 57 | */ |
| 58 | |
| 59 | #include <linux/bitmap.h> |
| 60 | #include <linux/bootmem.h> |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 61 | #include <linux/err.h> |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 62 | #include <linux/list.h> |
Tejun Heo | a530b79 | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 63 | #include <linux/log2.h> |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 64 | #include <linux/mm.h> |
| 65 | #include <linux/module.h> |
| 66 | #include <linux/mutex.h> |
| 67 | #include <linux/percpu.h> |
| 68 | #include <linux/pfn.h> |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 69 | #include <linux/slab.h> |
Tejun Heo | ccea34b | 2009-03-07 00:44:13 +0900 | [diff] [blame] | 70 | #include <linux/spinlock.h> |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 71 | #include <linux/vmalloc.h> |
Tejun Heo | a56dbdd | 2009-03-07 00:44:11 +0900 | [diff] [blame] | 72 | #include <linux/workqueue.h> |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 73 | |
| 74 | #include <asm/cacheflush.h> |
Tejun Heo | e010098 | 2009-03-10 16:27:48 +0900 | [diff] [blame] | 75 | #include <asm/sections.h> |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 76 | #include <asm/tlbflush.h> |
| 77 | |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 78 | #define PCPU_SLOT_BASE_SHIFT 5 /* 1-31 shares the same slot */ |
| 79 | #define PCPU_DFL_MAP_ALLOC 16 /* start a map with 16 ents */ |
| 80 | |
Tejun Heo | e010098 | 2009-03-10 16:27:48 +0900 | [diff] [blame] | 81 | /* default addr <-> pcpu_ptr mapping, override in asm/percpu.h if necessary */ |
| 82 | #ifndef __addr_to_pcpu_ptr |
| 83 | #define __addr_to_pcpu_ptr(addr) \ |
| 84 | (void *)((unsigned long)(addr) - (unsigned long)pcpu_base_addr \ |
| 85 | + (unsigned long)__per_cpu_start) |
| 86 | #endif |
| 87 | #ifndef __pcpu_ptr_to_addr |
| 88 | #define __pcpu_ptr_to_addr(ptr) \ |
| 89 | (void *)((unsigned long)(ptr) + (unsigned long)pcpu_base_addr \ |
| 90 | - (unsigned long)__per_cpu_start) |
| 91 | #endif |
| 92 | |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 93 | struct pcpu_chunk { |
| 94 | struct list_head list; /* linked to pcpu_slot lists */ |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 95 | int free_size; /* free bytes in the chunk */ |
| 96 | int contig_hint; /* max contiguous size hint */ |
Tejun Heo | bba174f | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 97 | void *base_addr; /* base address of this chunk */ |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 98 | int map_used; /* # of map entries used */ |
| 99 | int map_alloc; /* # of map entries allocated */ |
| 100 | int *map; /* allocation map */ |
Tejun Heo | bba174f | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 101 | struct vm_struct *vm; /* mapped vmalloc region */ |
Tejun Heo | 8d408b4 | 2009-02-24 11:57:21 +0900 | [diff] [blame] | 102 | bool immutable; /* no [de]population allowed */ |
Tejun Heo | ce3141a | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 103 | unsigned long populated[]; /* populated bitmap */ |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 104 | }; |
| 105 | |
Tejun Heo | 40150d3 | 2009-02-24 12:32:28 +0900 | [diff] [blame] | 106 | static int pcpu_unit_pages __read_mostly; |
| 107 | static int pcpu_unit_size __read_mostly; |
Tejun Heo | 2f39e63 | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 108 | static int pcpu_nr_units __read_mostly; |
Tejun Heo | 40150d3 | 2009-02-24 12:32:28 +0900 | [diff] [blame] | 109 | static int pcpu_chunk_size __read_mostly; |
| 110 | static int pcpu_nr_slots __read_mostly; |
| 111 | static size_t pcpu_chunk_struct_size __read_mostly; |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 112 | |
Tejun Heo | 2f39e63 | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 113 | /* cpus with the lowest and highest unit numbers */ |
| 114 | static unsigned int pcpu_first_unit_cpu __read_mostly; |
| 115 | static unsigned int pcpu_last_unit_cpu __read_mostly; |
| 116 | |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 117 | /* the address of the first chunk which starts with the kernel static area */ |
Tejun Heo | 40150d3 | 2009-02-24 12:32:28 +0900 | [diff] [blame] | 118 | void *pcpu_base_addr __read_mostly; |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 119 | EXPORT_SYMBOL_GPL(pcpu_base_addr); |
| 120 | |
Tejun Heo | fb435d5 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 121 | static const int *pcpu_unit_map __read_mostly; /* cpu -> unit */ |
| 122 | const unsigned long *pcpu_unit_offsets __read_mostly; /* cpu -> unit offset */ |
Tejun Heo | 2f39e63 | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 123 | |
Tejun Heo | ae9e6bc | 2009-04-02 13:19:54 +0900 | [diff] [blame] | 124 | /* |
| 125 | * The first chunk which always exists. Note that unlike other |
| 126 | * chunks, this one can be allocated and mapped in several different |
| 127 | * ways and thus often doesn't live in the vmalloc area. |
| 128 | */ |
| 129 | static struct pcpu_chunk *pcpu_first_chunk; |
| 130 | |
| 131 | /* |
| 132 | * Optional reserved chunk. This chunk reserves part of the first |
| 133 | * chunk and serves it for reserved allocations. The amount of |
| 134 | * reserved offset is in pcpu_reserved_chunk_limit. When reserved |
| 135 | * area doesn't exist, the following variables contain NULL and 0 |
| 136 | * respectively. |
| 137 | */ |
Tejun Heo | edcb463 | 2009-03-06 14:33:59 +0900 | [diff] [blame] | 138 | static struct pcpu_chunk *pcpu_reserved_chunk; |
Tejun Heo | edcb463 | 2009-03-06 14:33:59 +0900 | [diff] [blame] | 139 | static int pcpu_reserved_chunk_limit; |
| 140 | |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 141 | /* |
Tejun Heo | ccea34b | 2009-03-07 00:44:13 +0900 | [diff] [blame] | 142 | * Synchronization rules. |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 143 | * |
Tejun Heo | ccea34b | 2009-03-07 00:44:13 +0900 | [diff] [blame] | 144 | * There are two locks - pcpu_alloc_mutex and pcpu_lock. The former |
Tejun Heo | ce3141a | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 145 | * protects allocation/reclaim paths, chunks, populated bitmap and |
| 146 | * vmalloc mapping. The latter is a spinlock and protects the index |
| 147 | * data structures - chunk slots, chunks and area maps in chunks. |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 148 | * |
Tejun Heo | ccea34b | 2009-03-07 00:44:13 +0900 | [diff] [blame] | 149 | * During allocation, pcpu_alloc_mutex is kept locked all the time and |
| 150 | * pcpu_lock is grabbed and released as necessary. All actual memory |
| 151 | * allocations are done using GFP_KERNEL with pcpu_lock released. |
| 152 | * |
| 153 | * Free path accesses and alters only the index data structures, so it |
| 154 | * can be safely called from atomic context. When memory needs to be |
| 155 | * returned to the system, free path schedules reclaim_work which |
| 156 | * grabs both pcpu_alloc_mutex and pcpu_lock, unlinks chunks to be |
| 157 | * reclaimed, release both locks and frees the chunks. Note that it's |
| 158 | * necessary to grab both locks to remove a chunk from circulation as |
| 159 | * allocation path might be referencing the chunk with only |
| 160 | * pcpu_alloc_mutex locked. |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 161 | */ |
Tejun Heo | ccea34b | 2009-03-07 00:44:13 +0900 | [diff] [blame] | 162 | static DEFINE_MUTEX(pcpu_alloc_mutex); /* protects whole alloc and reclaim */ |
| 163 | static DEFINE_SPINLOCK(pcpu_lock); /* protects index data structures */ |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 164 | |
Tejun Heo | 40150d3 | 2009-02-24 12:32:28 +0900 | [diff] [blame] | 165 | static struct list_head *pcpu_slot __read_mostly; /* chunk list slots */ |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 166 | |
Tejun Heo | a56dbdd | 2009-03-07 00:44:11 +0900 | [diff] [blame] | 167 | /* reclaim work to release fully free chunks, scheduled from free path */ |
| 168 | static void pcpu_reclaim(struct work_struct *work); |
| 169 | static DECLARE_WORK(pcpu_reclaim_work, pcpu_reclaim); |
| 170 | |
Tejun Heo | d9b55ee | 2009-02-24 11:57:21 +0900 | [diff] [blame] | 171 | static int __pcpu_size_to_slot(int size) |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 172 | { |
Tejun Heo | cae3aeb | 2009-02-21 16:56:23 +0900 | [diff] [blame] | 173 | int highbit = fls(size); /* size is in bytes */ |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 174 | return max(highbit - PCPU_SLOT_BASE_SHIFT + 2, 1); |
| 175 | } |
| 176 | |
Tejun Heo | d9b55ee | 2009-02-24 11:57:21 +0900 | [diff] [blame] | 177 | static int pcpu_size_to_slot(int size) |
| 178 | { |
| 179 | if (size == pcpu_unit_size) |
| 180 | return pcpu_nr_slots - 1; |
| 181 | return __pcpu_size_to_slot(size); |
| 182 | } |
| 183 | |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 184 | static int pcpu_chunk_slot(const struct pcpu_chunk *chunk) |
| 185 | { |
| 186 | if (chunk->free_size < sizeof(int) || chunk->contig_hint < sizeof(int)) |
| 187 | return 0; |
| 188 | |
| 189 | return pcpu_size_to_slot(chunk->free_size); |
| 190 | } |
| 191 | |
| 192 | static int pcpu_page_idx(unsigned int cpu, int page_idx) |
| 193 | { |
Tejun Heo | 2f39e63 | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 194 | return pcpu_unit_map[cpu] * pcpu_unit_pages + page_idx; |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 195 | } |
| 196 | |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 197 | static unsigned long pcpu_chunk_addr(struct pcpu_chunk *chunk, |
| 198 | unsigned int cpu, int page_idx) |
| 199 | { |
Tejun Heo | bba174f | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 200 | return (unsigned long)chunk->base_addr + pcpu_unit_offsets[cpu] + |
Tejun Heo | fb435d5 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 201 | (page_idx << PAGE_SHIFT); |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 202 | } |
| 203 | |
Tejun Heo | ce3141a | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 204 | static struct page *pcpu_chunk_page(struct pcpu_chunk *chunk, |
| 205 | unsigned int cpu, int page_idx) |
Tejun Heo | c8a51be | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 206 | { |
Tejun Heo | ce3141a | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 207 | /* must not be used on pre-mapped chunk */ |
| 208 | WARN_ON(chunk->immutable); |
Tejun Heo | c8a51be | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 209 | |
Tejun Heo | ce3141a | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 210 | return vmalloc_to_page((void *)pcpu_chunk_addr(chunk, cpu, page_idx)); |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 211 | } |
| 212 | |
Christoph Lameter | e1b9aa3 | 2009-04-02 13:21:44 +0900 | [diff] [blame] | 213 | /* set the pointer to a chunk in a page struct */ |
| 214 | static void pcpu_set_page_chunk(struct page *page, struct pcpu_chunk *pcpu) |
| 215 | { |
| 216 | page->index = (unsigned long)pcpu; |
| 217 | } |
| 218 | |
| 219 | /* obtain pointer to a chunk from a page struct */ |
| 220 | static struct pcpu_chunk *pcpu_get_page_chunk(struct page *page) |
| 221 | { |
| 222 | return (struct pcpu_chunk *)page->index; |
| 223 | } |
| 224 | |
Tejun Heo | ce3141a | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 225 | static void pcpu_next_unpop(struct pcpu_chunk *chunk, int *rs, int *re, int end) |
| 226 | { |
| 227 | *rs = find_next_zero_bit(chunk->populated, end, *rs); |
| 228 | *re = find_next_bit(chunk->populated, end, *rs + 1); |
| 229 | } |
| 230 | |
| 231 | static void pcpu_next_pop(struct pcpu_chunk *chunk, int *rs, int *re, int end) |
| 232 | { |
| 233 | *rs = find_next_bit(chunk->populated, end, *rs); |
| 234 | *re = find_next_zero_bit(chunk->populated, end, *rs + 1); |
| 235 | } |
| 236 | |
| 237 | /* |
| 238 | * (Un)populated page region iterators. Iterate over (un)populated |
| 239 | * page regions betwen @start and @end in @chunk. @rs and @re should |
| 240 | * be integer variables and will be set to start and end page index of |
| 241 | * the current region. |
| 242 | */ |
| 243 | #define pcpu_for_each_unpop_region(chunk, rs, re, start, end) \ |
| 244 | for ((rs) = (start), pcpu_next_unpop((chunk), &(rs), &(re), (end)); \ |
| 245 | (rs) < (re); \ |
| 246 | (rs) = (re) + 1, pcpu_next_unpop((chunk), &(rs), &(re), (end))) |
| 247 | |
| 248 | #define pcpu_for_each_pop_region(chunk, rs, re, start, end) \ |
| 249 | for ((rs) = (start), pcpu_next_pop((chunk), &(rs), &(re), (end)); \ |
| 250 | (rs) < (re); \ |
| 251 | (rs) = (re) + 1, pcpu_next_pop((chunk), &(rs), &(re), (end))) |
| 252 | |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 253 | /** |
Tejun Heo | 1880d93 | 2009-03-07 00:44:09 +0900 | [diff] [blame] | 254 | * pcpu_mem_alloc - allocate memory |
| 255 | * @size: bytes to allocate |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 256 | * |
Tejun Heo | 1880d93 | 2009-03-07 00:44:09 +0900 | [diff] [blame] | 257 | * Allocate @size bytes. If @size is smaller than PAGE_SIZE, |
| 258 | * kzalloc() is used; otherwise, vmalloc() is used. The returned |
| 259 | * memory is always zeroed. |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 260 | * |
Tejun Heo | ccea34b | 2009-03-07 00:44:13 +0900 | [diff] [blame] | 261 | * CONTEXT: |
| 262 | * Does GFP_KERNEL allocation. |
| 263 | * |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 264 | * RETURNS: |
Tejun Heo | 1880d93 | 2009-03-07 00:44:09 +0900 | [diff] [blame] | 265 | * Pointer to the allocated area on success, NULL on failure. |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 266 | */ |
Tejun Heo | 1880d93 | 2009-03-07 00:44:09 +0900 | [diff] [blame] | 267 | static void *pcpu_mem_alloc(size_t size) |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 268 | { |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 269 | if (size <= PAGE_SIZE) |
Tejun Heo | 1880d93 | 2009-03-07 00:44:09 +0900 | [diff] [blame] | 270 | return kzalloc(size, GFP_KERNEL); |
| 271 | else { |
| 272 | void *ptr = vmalloc(size); |
| 273 | if (ptr) |
| 274 | memset(ptr, 0, size); |
| 275 | return ptr; |
| 276 | } |
| 277 | } |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 278 | |
Tejun Heo | 1880d93 | 2009-03-07 00:44:09 +0900 | [diff] [blame] | 279 | /** |
| 280 | * pcpu_mem_free - free memory |
| 281 | * @ptr: memory to free |
| 282 | * @size: size of the area |
| 283 | * |
| 284 | * Free @ptr. @ptr should have been allocated using pcpu_mem_alloc(). |
| 285 | */ |
| 286 | static void pcpu_mem_free(void *ptr, size_t size) |
| 287 | { |
| 288 | if (size <= PAGE_SIZE) |
| 289 | kfree(ptr); |
| 290 | else |
| 291 | vfree(ptr); |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 292 | } |
| 293 | |
| 294 | /** |
| 295 | * pcpu_chunk_relocate - put chunk in the appropriate chunk slot |
| 296 | * @chunk: chunk of interest |
| 297 | * @oslot: the previous slot it was on |
| 298 | * |
| 299 | * This function is called after an allocation or free changed @chunk. |
| 300 | * New slot according to the changed state is determined and @chunk is |
Tejun Heo | edcb463 | 2009-03-06 14:33:59 +0900 | [diff] [blame] | 301 | * moved to the slot. Note that the reserved chunk is never put on |
| 302 | * chunk slots. |
Tejun Heo | ccea34b | 2009-03-07 00:44:13 +0900 | [diff] [blame] | 303 | * |
| 304 | * CONTEXT: |
| 305 | * pcpu_lock. |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 306 | */ |
| 307 | static void pcpu_chunk_relocate(struct pcpu_chunk *chunk, int oslot) |
| 308 | { |
| 309 | int nslot = pcpu_chunk_slot(chunk); |
| 310 | |
Tejun Heo | edcb463 | 2009-03-06 14:33:59 +0900 | [diff] [blame] | 311 | if (chunk != pcpu_reserved_chunk && oslot != nslot) { |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 312 | if (oslot < nslot) |
| 313 | list_move(&chunk->list, &pcpu_slot[nslot]); |
| 314 | else |
| 315 | list_move_tail(&chunk->list, &pcpu_slot[nslot]); |
| 316 | } |
| 317 | } |
| 318 | |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 319 | /** |
Christoph Lameter | e1b9aa3 | 2009-04-02 13:21:44 +0900 | [diff] [blame] | 320 | * pcpu_chunk_addr_search - determine chunk containing specified address |
| 321 | * @addr: address for which the chunk needs to be determined. |
Tejun Heo | ccea34b | 2009-03-07 00:44:13 +0900 | [diff] [blame] | 322 | * |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 323 | * RETURNS: |
| 324 | * The address of the found chunk. |
| 325 | */ |
| 326 | static struct pcpu_chunk *pcpu_chunk_addr_search(void *addr) |
| 327 | { |
Tejun Heo | bba174f | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 328 | void *first_start = pcpu_first_chunk->base_addr; |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 329 | |
Tejun Heo | ae9e6bc | 2009-04-02 13:19:54 +0900 | [diff] [blame] | 330 | /* is it in the first chunk? */ |
Tejun Heo | 79ba6ac | 2009-07-04 08:10:58 +0900 | [diff] [blame] | 331 | if (addr >= first_start && addr < first_start + pcpu_unit_size) { |
Tejun Heo | ae9e6bc | 2009-04-02 13:19:54 +0900 | [diff] [blame] | 332 | /* is it in the reserved area? */ |
| 333 | if (addr < first_start + pcpu_reserved_chunk_limit) |
Tejun Heo | edcb463 | 2009-03-06 14:33:59 +0900 | [diff] [blame] | 334 | return pcpu_reserved_chunk; |
Tejun Heo | ae9e6bc | 2009-04-02 13:19:54 +0900 | [diff] [blame] | 335 | return pcpu_first_chunk; |
Tejun Heo | edcb463 | 2009-03-06 14:33:59 +0900 | [diff] [blame] | 336 | } |
| 337 | |
Tejun Heo | 2f39e63 | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 338 | /* |
| 339 | * The address is relative to unit0 which might be unused and |
| 340 | * thus unmapped. Offset the address to the unit space of the |
| 341 | * current processor before looking it up in the vmalloc |
| 342 | * space. Note that any possible cpu id can be used here, so |
| 343 | * there's no need to worry about preemption or cpu hotplug. |
| 344 | */ |
Tejun Heo | fb435d5 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 345 | addr += pcpu_unit_offsets[smp_processor_id()]; |
Christoph Lameter | e1b9aa3 | 2009-04-02 13:21:44 +0900 | [diff] [blame] | 346 | return pcpu_get_page_chunk(vmalloc_to_page(addr)); |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 347 | } |
| 348 | |
| 349 | /** |
Tejun Heo | 9f7dcf2 | 2009-03-07 00:44:09 +0900 | [diff] [blame] | 350 | * pcpu_extend_area_map - extend area map for allocation |
| 351 | * @chunk: target chunk |
| 352 | * |
| 353 | * Extend area map of @chunk so that it can accomodate an allocation. |
| 354 | * A single allocation can split an area into three areas, so this |
| 355 | * function makes sure that @chunk->map has at least two extra slots. |
| 356 | * |
Tejun Heo | ccea34b | 2009-03-07 00:44:13 +0900 | [diff] [blame] | 357 | * CONTEXT: |
| 358 | * pcpu_alloc_mutex, pcpu_lock. pcpu_lock is released and reacquired |
| 359 | * if area map is extended. |
| 360 | * |
Tejun Heo | 9f7dcf2 | 2009-03-07 00:44:09 +0900 | [diff] [blame] | 361 | * RETURNS: |
| 362 | * 0 if noop, 1 if successfully extended, -errno on failure. |
| 363 | */ |
| 364 | static int pcpu_extend_area_map(struct pcpu_chunk *chunk) |
| 365 | { |
| 366 | int new_alloc; |
| 367 | int *new; |
| 368 | size_t size; |
| 369 | |
| 370 | /* has enough? */ |
| 371 | if (chunk->map_alloc >= chunk->map_used + 2) |
| 372 | return 0; |
| 373 | |
Tejun Heo | ccea34b | 2009-03-07 00:44:13 +0900 | [diff] [blame] | 374 | spin_unlock_irq(&pcpu_lock); |
| 375 | |
Tejun Heo | 9f7dcf2 | 2009-03-07 00:44:09 +0900 | [diff] [blame] | 376 | new_alloc = PCPU_DFL_MAP_ALLOC; |
| 377 | while (new_alloc < chunk->map_used + 2) |
| 378 | new_alloc *= 2; |
| 379 | |
| 380 | new = pcpu_mem_alloc(new_alloc * sizeof(new[0])); |
Tejun Heo | ccea34b | 2009-03-07 00:44:13 +0900 | [diff] [blame] | 381 | if (!new) { |
| 382 | spin_lock_irq(&pcpu_lock); |
Tejun Heo | 9f7dcf2 | 2009-03-07 00:44:09 +0900 | [diff] [blame] | 383 | return -ENOMEM; |
Tejun Heo | ccea34b | 2009-03-07 00:44:13 +0900 | [diff] [blame] | 384 | } |
| 385 | |
| 386 | /* |
| 387 | * Acquire pcpu_lock and switch to new area map. Only free |
| 388 | * could have happened inbetween, so map_used couldn't have |
| 389 | * grown. |
| 390 | */ |
| 391 | spin_lock_irq(&pcpu_lock); |
| 392 | BUG_ON(new_alloc < chunk->map_used + 2); |
Tejun Heo | 9f7dcf2 | 2009-03-07 00:44:09 +0900 | [diff] [blame] | 393 | |
| 394 | size = chunk->map_alloc * sizeof(chunk->map[0]); |
| 395 | memcpy(new, chunk->map, size); |
| 396 | |
| 397 | /* |
| 398 | * map_alloc < PCPU_DFL_MAP_ALLOC indicates that the chunk is |
| 399 | * one of the first chunks and still using static map. |
| 400 | */ |
| 401 | if (chunk->map_alloc >= PCPU_DFL_MAP_ALLOC) |
| 402 | pcpu_mem_free(chunk->map, size); |
| 403 | |
| 404 | chunk->map_alloc = new_alloc; |
| 405 | chunk->map = new; |
| 406 | return 0; |
| 407 | } |
| 408 | |
| 409 | /** |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 410 | * pcpu_split_block - split a map block |
| 411 | * @chunk: chunk of interest |
| 412 | * @i: index of map block to split |
Tejun Heo | cae3aeb | 2009-02-21 16:56:23 +0900 | [diff] [blame] | 413 | * @head: head size in bytes (can be 0) |
| 414 | * @tail: tail size in bytes (can be 0) |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 415 | * |
| 416 | * Split the @i'th map block into two or three blocks. If @head is |
| 417 | * non-zero, @head bytes block is inserted before block @i moving it |
| 418 | * to @i+1 and reducing its size by @head bytes. |
| 419 | * |
| 420 | * If @tail is non-zero, the target block, which can be @i or @i+1 |
| 421 | * depending on @head, is reduced by @tail bytes and @tail byte block |
| 422 | * is inserted after the target block. |
| 423 | * |
Tejun Heo | 9f7dcf2 | 2009-03-07 00:44:09 +0900 | [diff] [blame] | 424 | * @chunk->map must have enough free slots to accomodate the split. |
Tejun Heo | ccea34b | 2009-03-07 00:44:13 +0900 | [diff] [blame] | 425 | * |
| 426 | * CONTEXT: |
| 427 | * pcpu_lock. |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 428 | */ |
Tejun Heo | 9f7dcf2 | 2009-03-07 00:44:09 +0900 | [diff] [blame] | 429 | static void pcpu_split_block(struct pcpu_chunk *chunk, int i, |
| 430 | int head, int tail) |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 431 | { |
| 432 | int nr_extra = !!head + !!tail; |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 433 | |
Tejun Heo | 9f7dcf2 | 2009-03-07 00:44:09 +0900 | [diff] [blame] | 434 | BUG_ON(chunk->map_alloc < chunk->map_used + nr_extra); |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 435 | |
Tejun Heo | 9f7dcf2 | 2009-03-07 00:44:09 +0900 | [diff] [blame] | 436 | /* insert new subblocks */ |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 437 | memmove(&chunk->map[i + nr_extra], &chunk->map[i], |
| 438 | sizeof(chunk->map[0]) * (chunk->map_used - i)); |
| 439 | chunk->map_used += nr_extra; |
| 440 | |
| 441 | if (head) { |
| 442 | chunk->map[i + 1] = chunk->map[i] - head; |
| 443 | chunk->map[i++] = head; |
| 444 | } |
| 445 | if (tail) { |
| 446 | chunk->map[i++] -= tail; |
| 447 | chunk->map[i] = tail; |
| 448 | } |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 449 | } |
| 450 | |
| 451 | /** |
| 452 | * pcpu_alloc_area - allocate area from a pcpu_chunk |
| 453 | * @chunk: chunk of interest |
Tejun Heo | cae3aeb | 2009-02-21 16:56:23 +0900 | [diff] [blame] | 454 | * @size: wanted size in bytes |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 455 | * @align: wanted align |
| 456 | * |
| 457 | * Try to allocate @size bytes area aligned at @align from @chunk. |
| 458 | * Note that this function only allocates the offset. It doesn't |
| 459 | * populate or map the area. |
| 460 | * |
Tejun Heo | 9f7dcf2 | 2009-03-07 00:44:09 +0900 | [diff] [blame] | 461 | * @chunk->map must have at least two free slots. |
| 462 | * |
Tejun Heo | ccea34b | 2009-03-07 00:44:13 +0900 | [diff] [blame] | 463 | * CONTEXT: |
| 464 | * pcpu_lock. |
| 465 | * |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 466 | * RETURNS: |
Tejun Heo | 9f7dcf2 | 2009-03-07 00:44:09 +0900 | [diff] [blame] | 467 | * Allocated offset in @chunk on success, -1 if no matching area is |
| 468 | * found. |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 469 | */ |
| 470 | static int pcpu_alloc_area(struct pcpu_chunk *chunk, int size, int align) |
| 471 | { |
| 472 | int oslot = pcpu_chunk_slot(chunk); |
| 473 | int max_contig = 0; |
| 474 | int i, off; |
| 475 | |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 476 | for (i = 0, off = 0; i < chunk->map_used; off += abs(chunk->map[i++])) { |
| 477 | bool is_last = i + 1 == chunk->map_used; |
| 478 | int head, tail; |
| 479 | |
| 480 | /* extra for alignment requirement */ |
| 481 | head = ALIGN(off, align) - off; |
| 482 | BUG_ON(i == 0 && head != 0); |
| 483 | |
| 484 | if (chunk->map[i] < 0) |
| 485 | continue; |
| 486 | if (chunk->map[i] < head + size) { |
| 487 | max_contig = max(chunk->map[i], max_contig); |
| 488 | continue; |
| 489 | } |
| 490 | |
| 491 | /* |
| 492 | * If head is small or the previous block is free, |
| 493 | * merge'em. Note that 'small' is defined as smaller |
| 494 | * than sizeof(int), which is very small but isn't too |
| 495 | * uncommon for percpu allocations. |
| 496 | */ |
| 497 | if (head && (head < sizeof(int) || chunk->map[i - 1] > 0)) { |
| 498 | if (chunk->map[i - 1] > 0) |
| 499 | chunk->map[i - 1] += head; |
| 500 | else { |
| 501 | chunk->map[i - 1] -= head; |
| 502 | chunk->free_size -= head; |
| 503 | } |
| 504 | chunk->map[i] -= head; |
| 505 | off += head; |
| 506 | head = 0; |
| 507 | } |
| 508 | |
| 509 | /* if tail is small, just keep it around */ |
| 510 | tail = chunk->map[i] - head - size; |
| 511 | if (tail < sizeof(int)) |
| 512 | tail = 0; |
| 513 | |
| 514 | /* split if warranted */ |
| 515 | if (head || tail) { |
Tejun Heo | 9f7dcf2 | 2009-03-07 00:44:09 +0900 | [diff] [blame] | 516 | pcpu_split_block(chunk, i, head, tail); |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 517 | if (head) { |
| 518 | i++; |
| 519 | off += head; |
| 520 | max_contig = max(chunk->map[i - 1], max_contig); |
| 521 | } |
| 522 | if (tail) |
| 523 | max_contig = max(chunk->map[i + 1], max_contig); |
| 524 | } |
| 525 | |
| 526 | /* update hint and mark allocated */ |
| 527 | if (is_last) |
| 528 | chunk->contig_hint = max_contig; /* fully scanned */ |
| 529 | else |
| 530 | chunk->contig_hint = max(chunk->contig_hint, |
| 531 | max_contig); |
| 532 | |
| 533 | chunk->free_size -= chunk->map[i]; |
| 534 | chunk->map[i] = -chunk->map[i]; |
| 535 | |
| 536 | pcpu_chunk_relocate(chunk, oslot); |
| 537 | return off; |
| 538 | } |
| 539 | |
| 540 | chunk->contig_hint = max_contig; /* fully scanned */ |
| 541 | pcpu_chunk_relocate(chunk, oslot); |
| 542 | |
Tejun Heo | 9f7dcf2 | 2009-03-07 00:44:09 +0900 | [diff] [blame] | 543 | /* tell the upper layer that this chunk has no matching area */ |
| 544 | return -1; |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 545 | } |
| 546 | |
| 547 | /** |
| 548 | * pcpu_free_area - free area to a pcpu_chunk |
| 549 | * @chunk: chunk of interest |
| 550 | * @freeme: offset of area to free |
| 551 | * |
| 552 | * Free area starting from @freeme to @chunk. Note that this function |
| 553 | * only modifies the allocation map. It doesn't depopulate or unmap |
| 554 | * the area. |
Tejun Heo | ccea34b | 2009-03-07 00:44:13 +0900 | [diff] [blame] | 555 | * |
| 556 | * CONTEXT: |
| 557 | * pcpu_lock. |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 558 | */ |
| 559 | static void pcpu_free_area(struct pcpu_chunk *chunk, int freeme) |
| 560 | { |
| 561 | int oslot = pcpu_chunk_slot(chunk); |
| 562 | int i, off; |
| 563 | |
| 564 | for (i = 0, off = 0; i < chunk->map_used; off += abs(chunk->map[i++])) |
| 565 | if (off == freeme) |
| 566 | break; |
| 567 | BUG_ON(off != freeme); |
| 568 | BUG_ON(chunk->map[i] > 0); |
| 569 | |
| 570 | chunk->map[i] = -chunk->map[i]; |
| 571 | chunk->free_size += chunk->map[i]; |
| 572 | |
| 573 | /* merge with previous? */ |
| 574 | if (i > 0 && chunk->map[i - 1] >= 0) { |
| 575 | chunk->map[i - 1] += chunk->map[i]; |
| 576 | chunk->map_used--; |
| 577 | memmove(&chunk->map[i], &chunk->map[i + 1], |
| 578 | (chunk->map_used - i) * sizeof(chunk->map[0])); |
| 579 | i--; |
| 580 | } |
| 581 | /* merge with next? */ |
| 582 | if (i + 1 < chunk->map_used && chunk->map[i + 1] >= 0) { |
| 583 | chunk->map[i] += chunk->map[i + 1]; |
| 584 | chunk->map_used--; |
| 585 | memmove(&chunk->map[i + 1], &chunk->map[i + 2], |
| 586 | (chunk->map_used - (i + 1)) * sizeof(chunk->map[0])); |
| 587 | } |
| 588 | |
| 589 | chunk->contig_hint = max(chunk->map[i], chunk->contig_hint); |
| 590 | pcpu_chunk_relocate(chunk, oslot); |
| 591 | } |
| 592 | |
| 593 | /** |
Tejun Heo | ce3141a | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 594 | * pcpu_get_pages_and_bitmap - get temp pages array and bitmap |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 595 | * @chunk: chunk of interest |
Tejun Heo | ce3141a | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 596 | * @bitmapp: output parameter for bitmap |
| 597 | * @may_alloc: may allocate the array |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 598 | * |
Tejun Heo | ce3141a | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 599 | * Returns pointer to array of pointers to struct page and bitmap, |
| 600 | * both of which can be indexed with pcpu_page_idx(). The returned |
| 601 | * array is cleared to zero and *@bitmapp is copied from |
| 602 | * @chunk->populated. Note that there is only one array and bitmap |
| 603 | * and access exclusion is the caller's responsibility. |
| 604 | * |
| 605 | * CONTEXT: |
| 606 | * pcpu_alloc_mutex and does GFP_KERNEL allocation if @may_alloc. |
| 607 | * Otherwise, don't care. |
| 608 | * |
| 609 | * RETURNS: |
| 610 | * Pointer to temp pages array on success, NULL on failure. |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 611 | */ |
Tejun Heo | ce3141a | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 612 | static struct page **pcpu_get_pages_and_bitmap(struct pcpu_chunk *chunk, |
| 613 | unsigned long **bitmapp, |
| 614 | bool may_alloc) |
| 615 | { |
| 616 | static struct page **pages; |
| 617 | static unsigned long *bitmap; |
Tejun Heo | 2f39e63 | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 618 | size_t pages_size = pcpu_nr_units * pcpu_unit_pages * sizeof(pages[0]); |
Tejun Heo | ce3141a | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 619 | size_t bitmap_size = BITS_TO_LONGS(pcpu_unit_pages) * |
| 620 | sizeof(unsigned long); |
| 621 | |
| 622 | if (!pages || !bitmap) { |
| 623 | if (may_alloc && !pages) |
| 624 | pages = pcpu_mem_alloc(pages_size); |
| 625 | if (may_alloc && !bitmap) |
| 626 | bitmap = pcpu_mem_alloc(bitmap_size); |
| 627 | if (!pages || !bitmap) |
| 628 | return NULL; |
| 629 | } |
| 630 | |
| 631 | memset(pages, 0, pages_size); |
| 632 | bitmap_copy(bitmap, chunk->populated, pcpu_unit_pages); |
| 633 | |
| 634 | *bitmapp = bitmap; |
| 635 | return pages; |
| 636 | } |
| 637 | |
| 638 | /** |
| 639 | * pcpu_free_pages - free pages which were allocated for @chunk |
| 640 | * @chunk: chunk pages were allocated for |
| 641 | * @pages: array of pages to be freed, indexed by pcpu_page_idx() |
| 642 | * @populated: populated bitmap |
| 643 | * @page_start: page index of the first page to be freed |
| 644 | * @page_end: page index of the last page to be freed + 1 |
| 645 | * |
| 646 | * Free pages [@page_start and @page_end) in @pages for all units. |
| 647 | * The pages were allocated for @chunk. |
| 648 | */ |
| 649 | static void pcpu_free_pages(struct pcpu_chunk *chunk, |
| 650 | struct page **pages, unsigned long *populated, |
| 651 | int page_start, int page_end) |
| 652 | { |
| 653 | unsigned int cpu; |
| 654 | int i; |
| 655 | |
| 656 | for_each_possible_cpu(cpu) { |
| 657 | for (i = page_start; i < page_end; i++) { |
| 658 | struct page *page = pages[pcpu_page_idx(cpu, i)]; |
| 659 | |
| 660 | if (page) |
| 661 | __free_page(page); |
| 662 | } |
| 663 | } |
| 664 | } |
| 665 | |
| 666 | /** |
| 667 | * pcpu_alloc_pages - allocates pages for @chunk |
| 668 | * @chunk: target chunk |
| 669 | * @pages: array to put the allocated pages into, indexed by pcpu_page_idx() |
| 670 | * @populated: populated bitmap |
| 671 | * @page_start: page index of the first page to be allocated |
| 672 | * @page_end: page index of the last page to be allocated + 1 |
| 673 | * |
| 674 | * Allocate pages [@page_start,@page_end) into @pages for all units. |
| 675 | * The allocation is for @chunk. Percpu core doesn't care about the |
| 676 | * content of @pages and will pass it verbatim to pcpu_map_pages(). |
| 677 | */ |
| 678 | static int pcpu_alloc_pages(struct pcpu_chunk *chunk, |
| 679 | struct page **pages, unsigned long *populated, |
| 680 | int page_start, int page_end) |
| 681 | { |
| 682 | const gfp_t gfp = GFP_KERNEL | __GFP_HIGHMEM | __GFP_COLD; |
| 683 | unsigned int cpu; |
| 684 | int i; |
| 685 | |
| 686 | for_each_possible_cpu(cpu) { |
| 687 | for (i = page_start; i < page_end; i++) { |
| 688 | struct page **pagep = &pages[pcpu_page_idx(cpu, i)]; |
| 689 | |
| 690 | *pagep = alloc_pages_node(cpu_to_node(cpu), gfp, 0); |
| 691 | if (!*pagep) { |
| 692 | pcpu_free_pages(chunk, pages, populated, |
| 693 | page_start, page_end); |
| 694 | return -ENOMEM; |
| 695 | } |
| 696 | } |
| 697 | } |
| 698 | return 0; |
| 699 | } |
| 700 | |
| 701 | /** |
| 702 | * pcpu_pre_unmap_flush - flush cache prior to unmapping |
| 703 | * @chunk: chunk the regions to be flushed belongs to |
| 704 | * @page_start: page index of the first page to be flushed |
| 705 | * @page_end: page index of the last page to be flushed + 1 |
| 706 | * |
| 707 | * Pages in [@page_start,@page_end) of @chunk are about to be |
| 708 | * unmapped. Flush cache. As each flushing trial can be very |
| 709 | * expensive, issue flush on the whole region at once rather than |
| 710 | * doing it for each cpu. This could be an overkill but is more |
| 711 | * scalable. |
| 712 | */ |
| 713 | static void pcpu_pre_unmap_flush(struct pcpu_chunk *chunk, |
| 714 | int page_start, int page_end) |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 715 | { |
Tejun Heo | 2f39e63 | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 716 | flush_cache_vunmap( |
| 717 | pcpu_chunk_addr(chunk, pcpu_first_unit_cpu, page_start), |
| 718 | pcpu_chunk_addr(chunk, pcpu_last_unit_cpu, page_end)); |
Tejun Heo | ce3141a | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 719 | } |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 720 | |
Tejun Heo | ce3141a | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 721 | static void __pcpu_unmap_pages(unsigned long addr, int nr_pages) |
| 722 | { |
| 723 | unmap_kernel_range_noflush(addr, nr_pages << PAGE_SHIFT); |
| 724 | } |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 725 | |
Tejun Heo | ce3141a | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 726 | /** |
| 727 | * pcpu_unmap_pages - unmap pages out of a pcpu_chunk |
| 728 | * @chunk: chunk of interest |
| 729 | * @pages: pages array which can be used to pass information to free |
| 730 | * @populated: populated bitmap |
| 731 | * @page_start: page index of the first page to unmap |
| 732 | * @page_end: page index of the last page to unmap + 1 |
| 733 | * |
| 734 | * For each cpu, unmap pages [@page_start,@page_end) out of @chunk. |
| 735 | * Corresponding elements in @pages were cleared by the caller and can |
| 736 | * be used to carry information to pcpu_free_pages() which will be |
| 737 | * called after all unmaps are finished. The caller should call |
| 738 | * proper pre/post flush functions. |
| 739 | */ |
| 740 | static void pcpu_unmap_pages(struct pcpu_chunk *chunk, |
| 741 | struct page **pages, unsigned long *populated, |
| 742 | int page_start, int page_end) |
| 743 | { |
| 744 | unsigned int cpu; |
| 745 | int i; |
| 746 | |
| 747 | for_each_possible_cpu(cpu) { |
| 748 | for (i = page_start; i < page_end; i++) { |
| 749 | struct page *page; |
| 750 | |
| 751 | page = pcpu_chunk_page(chunk, cpu, i); |
| 752 | WARN_ON(!page); |
| 753 | pages[pcpu_page_idx(cpu, i)] = page; |
| 754 | } |
| 755 | __pcpu_unmap_pages(pcpu_chunk_addr(chunk, cpu, page_start), |
| 756 | page_end - page_start); |
| 757 | } |
| 758 | |
| 759 | for (i = page_start; i < page_end; i++) |
| 760 | __clear_bit(i, populated); |
| 761 | } |
| 762 | |
| 763 | /** |
| 764 | * pcpu_post_unmap_tlb_flush - flush TLB after unmapping |
| 765 | * @chunk: pcpu_chunk the regions to be flushed belong to |
| 766 | * @page_start: page index of the first page to be flushed |
| 767 | * @page_end: page index of the last page to be flushed + 1 |
| 768 | * |
| 769 | * Pages [@page_start,@page_end) of @chunk have been unmapped. Flush |
| 770 | * TLB for the regions. This can be skipped if the area is to be |
| 771 | * returned to vmalloc as vmalloc will handle TLB flushing lazily. |
| 772 | * |
| 773 | * As with pcpu_pre_unmap_flush(), TLB flushing also is done at once |
| 774 | * for the whole region. |
| 775 | */ |
| 776 | static void pcpu_post_unmap_tlb_flush(struct pcpu_chunk *chunk, |
| 777 | int page_start, int page_end) |
| 778 | { |
Tejun Heo | 2f39e63 | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 779 | flush_tlb_kernel_range( |
| 780 | pcpu_chunk_addr(chunk, pcpu_first_unit_cpu, page_start), |
| 781 | pcpu_chunk_addr(chunk, pcpu_last_unit_cpu, page_end)); |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 782 | } |
| 783 | |
Tejun Heo | c8a51be | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 784 | static int __pcpu_map_pages(unsigned long addr, struct page **pages, |
| 785 | int nr_pages) |
| 786 | { |
| 787 | return map_kernel_range_noflush(addr, nr_pages << PAGE_SHIFT, |
| 788 | PAGE_KERNEL, pages); |
| 789 | } |
| 790 | |
| 791 | /** |
Tejun Heo | ce3141a | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 792 | * pcpu_map_pages - map pages into a pcpu_chunk |
Tejun Heo | c8a51be | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 793 | * @chunk: chunk of interest |
Tejun Heo | ce3141a | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 794 | * @pages: pages array containing pages to be mapped |
| 795 | * @populated: populated bitmap |
Tejun Heo | c8a51be | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 796 | * @page_start: page index of the first page to map |
| 797 | * @page_end: page index of the last page to map + 1 |
| 798 | * |
Tejun Heo | ce3141a | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 799 | * For each cpu, map pages [@page_start,@page_end) into @chunk. The |
| 800 | * caller is responsible for calling pcpu_post_map_flush() after all |
| 801 | * mappings are complete. |
| 802 | * |
| 803 | * This function is responsible for setting corresponding bits in |
| 804 | * @chunk->populated bitmap and whatever is necessary for reverse |
| 805 | * lookup (addr -> chunk). |
Tejun Heo | c8a51be | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 806 | */ |
Tejun Heo | ce3141a | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 807 | static int pcpu_map_pages(struct pcpu_chunk *chunk, |
| 808 | struct page **pages, unsigned long *populated, |
| 809 | int page_start, int page_end) |
Tejun Heo | c8a51be | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 810 | { |
Tejun Heo | ce3141a | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 811 | unsigned int cpu, tcpu; |
| 812 | int i, err; |
Tejun Heo | c8a51be | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 813 | |
| 814 | for_each_possible_cpu(cpu) { |
| 815 | err = __pcpu_map_pages(pcpu_chunk_addr(chunk, cpu, page_start), |
Tejun Heo | ce3141a | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 816 | &pages[pcpu_page_idx(cpu, page_start)], |
Tejun Heo | c8a51be | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 817 | page_end - page_start); |
| 818 | if (err < 0) |
Tejun Heo | ce3141a | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 819 | goto err; |
Tejun Heo | c8a51be | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 820 | } |
| 821 | |
Tejun Heo | ce3141a | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 822 | /* mapping successful, link chunk and mark populated */ |
| 823 | for (i = page_start; i < page_end; i++) { |
| 824 | for_each_possible_cpu(cpu) |
| 825 | pcpu_set_page_chunk(pages[pcpu_page_idx(cpu, i)], |
| 826 | chunk); |
| 827 | __set_bit(i, populated); |
| 828 | } |
| 829 | |
| 830 | return 0; |
| 831 | |
| 832 | err: |
| 833 | for_each_possible_cpu(tcpu) { |
| 834 | if (tcpu == cpu) |
| 835 | break; |
| 836 | __pcpu_unmap_pages(pcpu_chunk_addr(chunk, tcpu, page_start), |
| 837 | page_end - page_start); |
| 838 | } |
| 839 | return err; |
| 840 | } |
| 841 | |
| 842 | /** |
| 843 | * pcpu_post_map_flush - flush cache after mapping |
| 844 | * @chunk: pcpu_chunk the regions to be flushed belong to |
| 845 | * @page_start: page index of the first page to be flushed |
| 846 | * @page_end: page index of the last page to be flushed + 1 |
| 847 | * |
| 848 | * Pages [@page_start,@page_end) of @chunk have been mapped. Flush |
| 849 | * cache. |
| 850 | * |
| 851 | * As with pcpu_pre_unmap_flush(), TLB flushing also is done at once |
| 852 | * for the whole region. |
| 853 | */ |
| 854 | static void pcpu_post_map_flush(struct pcpu_chunk *chunk, |
| 855 | int page_start, int page_end) |
| 856 | { |
Tejun Heo | 2f39e63 | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 857 | flush_cache_vmap( |
| 858 | pcpu_chunk_addr(chunk, pcpu_first_unit_cpu, page_start), |
| 859 | pcpu_chunk_addr(chunk, pcpu_last_unit_cpu, page_end)); |
Tejun Heo | c8a51be | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 860 | } |
| 861 | |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 862 | /** |
| 863 | * pcpu_depopulate_chunk - depopulate and unmap an area of a pcpu_chunk |
| 864 | * @chunk: chunk to depopulate |
| 865 | * @off: offset to the area to depopulate |
Tejun Heo | cae3aeb | 2009-02-21 16:56:23 +0900 | [diff] [blame] | 866 | * @size: size of the area to depopulate in bytes |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 867 | * @flush: whether to flush cache and tlb or not |
| 868 | * |
| 869 | * For each cpu, depopulate and unmap pages [@page_start,@page_end) |
| 870 | * from @chunk. If @flush is true, vcache is flushed before unmapping |
| 871 | * and tlb after. |
Tejun Heo | ccea34b | 2009-03-07 00:44:13 +0900 | [diff] [blame] | 872 | * |
| 873 | * CONTEXT: |
| 874 | * pcpu_alloc_mutex. |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 875 | */ |
Tejun Heo | ce3141a | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 876 | static void pcpu_depopulate_chunk(struct pcpu_chunk *chunk, int off, int size) |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 877 | { |
| 878 | int page_start = PFN_DOWN(off); |
| 879 | int page_end = PFN_UP(off + size); |
Tejun Heo | ce3141a | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 880 | struct page **pages; |
| 881 | unsigned long *populated; |
| 882 | int rs, re; |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 883 | |
Tejun Heo | ce3141a | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 884 | /* quick path, check whether it's empty already */ |
| 885 | pcpu_for_each_unpop_region(chunk, rs, re, page_start, page_end) { |
| 886 | if (rs == page_start && re == page_end) |
| 887 | return; |
| 888 | break; |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 889 | } |
| 890 | |
Tejun Heo | ce3141a | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 891 | /* immutable chunks can't be depopulated */ |
| 892 | WARN_ON(chunk->immutable); |
| 893 | |
| 894 | /* |
| 895 | * If control reaches here, there must have been at least one |
| 896 | * successful population attempt so the temp pages array must |
| 897 | * be available now. |
| 898 | */ |
| 899 | pages = pcpu_get_pages_and_bitmap(chunk, &populated, false); |
| 900 | BUG_ON(!pages); |
| 901 | |
| 902 | /* unmap and free */ |
| 903 | pcpu_pre_unmap_flush(chunk, page_start, page_end); |
| 904 | |
| 905 | pcpu_for_each_pop_region(chunk, rs, re, page_start, page_end) |
| 906 | pcpu_unmap_pages(chunk, pages, populated, rs, re); |
| 907 | |
| 908 | /* no need to flush tlb, vmalloc will handle it lazily */ |
| 909 | |
| 910 | pcpu_for_each_pop_region(chunk, rs, re, page_start, page_end) |
| 911 | pcpu_free_pages(chunk, pages, populated, rs, re); |
| 912 | |
| 913 | /* commit new bitmap */ |
| 914 | bitmap_copy(chunk->populated, populated, pcpu_unit_pages); |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 915 | } |
| 916 | |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 917 | /** |
| 918 | * pcpu_populate_chunk - populate and map an area of a pcpu_chunk |
| 919 | * @chunk: chunk of interest |
| 920 | * @off: offset to the area to populate |
Tejun Heo | cae3aeb | 2009-02-21 16:56:23 +0900 | [diff] [blame] | 921 | * @size: size of the area to populate in bytes |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 922 | * |
| 923 | * For each cpu, populate and map pages [@page_start,@page_end) into |
| 924 | * @chunk. The area is cleared on return. |
Tejun Heo | ccea34b | 2009-03-07 00:44:13 +0900 | [diff] [blame] | 925 | * |
| 926 | * CONTEXT: |
| 927 | * pcpu_alloc_mutex, does GFP_KERNEL allocation. |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 928 | */ |
| 929 | static int pcpu_populate_chunk(struct pcpu_chunk *chunk, int off, int size) |
| 930 | { |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 931 | int page_start = PFN_DOWN(off); |
| 932 | int page_end = PFN_UP(off + size); |
Tejun Heo | ce3141a | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 933 | int free_end = page_start, unmap_end = page_start; |
| 934 | struct page **pages; |
| 935 | unsigned long *populated; |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 936 | unsigned int cpu; |
Tejun Heo | ce3141a | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 937 | int rs, re, rc; |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 938 | |
Tejun Heo | ce3141a | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 939 | /* quick path, check whether all pages are already there */ |
| 940 | pcpu_for_each_pop_region(chunk, rs, re, page_start, page_end) { |
| 941 | if (rs == page_start && re == page_end) |
| 942 | goto clear; |
| 943 | break; |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 944 | } |
| 945 | |
Tejun Heo | ce3141a | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 946 | /* need to allocate and map pages, this chunk can't be immutable */ |
| 947 | WARN_ON(chunk->immutable); |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 948 | |
Tejun Heo | ce3141a | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 949 | pages = pcpu_get_pages_and_bitmap(chunk, &populated, true); |
| 950 | if (!pages) |
| 951 | return -ENOMEM; |
| 952 | |
| 953 | /* alloc and map */ |
| 954 | pcpu_for_each_unpop_region(chunk, rs, re, page_start, page_end) { |
| 955 | rc = pcpu_alloc_pages(chunk, pages, populated, rs, re); |
| 956 | if (rc) |
| 957 | goto err_free; |
| 958 | free_end = re; |
| 959 | } |
| 960 | |
| 961 | pcpu_for_each_unpop_region(chunk, rs, re, page_start, page_end) { |
| 962 | rc = pcpu_map_pages(chunk, pages, populated, rs, re); |
| 963 | if (rc) |
| 964 | goto err_unmap; |
| 965 | unmap_end = re; |
| 966 | } |
| 967 | pcpu_post_map_flush(chunk, page_start, page_end); |
| 968 | |
| 969 | /* commit new bitmap */ |
| 970 | bitmap_copy(chunk->populated, populated, pcpu_unit_pages); |
| 971 | clear: |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 972 | for_each_possible_cpu(cpu) |
Tejun Heo | 2f39e63 | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 973 | memset((void *)pcpu_chunk_addr(chunk, cpu, 0) + off, 0, size); |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 974 | return 0; |
Tejun Heo | ce3141a | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 975 | |
| 976 | err_unmap: |
| 977 | pcpu_pre_unmap_flush(chunk, page_start, unmap_end); |
| 978 | pcpu_for_each_unpop_region(chunk, rs, re, page_start, unmap_end) |
| 979 | pcpu_unmap_pages(chunk, pages, populated, rs, re); |
| 980 | pcpu_post_unmap_tlb_flush(chunk, page_start, unmap_end); |
| 981 | err_free: |
| 982 | pcpu_for_each_unpop_region(chunk, rs, re, page_start, free_end) |
| 983 | pcpu_free_pages(chunk, pages, populated, rs, re); |
| 984 | return rc; |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 985 | } |
| 986 | |
| 987 | static void free_pcpu_chunk(struct pcpu_chunk *chunk) |
| 988 | { |
| 989 | if (!chunk) |
| 990 | return; |
| 991 | if (chunk->vm) |
| 992 | free_vm_area(chunk->vm); |
Tejun Heo | 1880d93 | 2009-03-07 00:44:09 +0900 | [diff] [blame] | 993 | pcpu_mem_free(chunk->map, chunk->map_alloc * sizeof(chunk->map[0])); |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 994 | kfree(chunk); |
| 995 | } |
| 996 | |
| 997 | static struct pcpu_chunk *alloc_pcpu_chunk(void) |
| 998 | { |
| 999 | struct pcpu_chunk *chunk; |
| 1000 | |
| 1001 | chunk = kzalloc(pcpu_chunk_struct_size, GFP_KERNEL); |
| 1002 | if (!chunk) |
| 1003 | return NULL; |
| 1004 | |
Tejun Heo | 1880d93 | 2009-03-07 00:44:09 +0900 | [diff] [blame] | 1005 | chunk->map = pcpu_mem_alloc(PCPU_DFL_MAP_ALLOC * sizeof(chunk->map[0])); |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 1006 | chunk->map_alloc = PCPU_DFL_MAP_ALLOC; |
| 1007 | chunk->map[chunk->map_used++] = pcpu_unit_size; |
| 1008 | |
Amerigo Wang | 142d44b | 2009-08-13 02:00:13 -0400 | [diff] [blame] | 1009 | chunk->vm = get_vm_area(pcpu_chunk_size, VM_ALLOC); |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 1010 | if (!chunk->vm) { |
| 1011 | free_pcpu_chunk(chunk); |
| 1012 | return NULL; |
| 1013 | } |
| 1014 | |
| 1015 | INIT_LIST_HEAD(&chunk->list); |
| 1016 | chunk->free_size = pcpu_unit_size; |
| 1017 | chunk->contig_hint = pcpu_unit_size; |
Tejun Heo | bba174f | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1018 | chunk->base_addr = chunk->vm->addr; |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 1019 | |
| 1020 | return chunk; |
| 1021 | } |
| 1022 | |
| 1023 | /** |
Tejun Heo | edcb463 | 2009-03-06 14:33:59 +0900 | [diff] [blame] | 1024 | * pcpu_alloc - the percpu allocator |
Tejun Heo | cae3aeb | 2009-02-21 16:56:23 +0900 | [diff] [blame] | 1025 | * @size: size of area to allocate in bytes |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 1026 | * @align: alignment of area (max PAGE_SIZE) |
Tejun Heo | edcb463 | 2009-03-06 14:33:59 +0900 | [diff] [blame] | 1027 | * @reserved: allocate from the reserved chunk if available |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 1028 | * |
Tejun Heo | ccea34b | 2009-03-07 00:44:13 +0900 | [diff] [blame] | 1029 | * Allocate percpu area of @size bytes aligned at @align. |
| 1030 | * |
| 1031 | * CONTEXT: |
| 1032 | * Does GFP_KERNEL allocation. |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 1033 | * |
| 1034 | * RETURNS: |
| 1035 | * Percpu pointer to the allocated area on success, NULL on failure. |
| 1036 | */ |
Tejun Heo | edcb463 | 2009-03-06 14:33:59 +0900 | [diff] [blame] | 1037 | static void *pcpu_alloc(size_t size, size_t align, bool reserved) |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 1038 | { |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 1039 | struct pcpu_chunk *chunk; |
| 1040 | int slot, off; |
| 1041 | |
Tejun Heo | 8d408b4 | 2009-02-24 11:57:21 +0900 | [diff] [blame] | 1042 | if (unlikely(!size || size > PCPU_MIN_UNIT_SIZE || align > PAGE_SIZE)) { |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 1043 | WARN(true, "illegal size (%zu) or align (%zu) for " |
| 1044 | "percpu allocation\n", size, align); |
| 1045 | return NULL; |
| 1046 | } |
| 1047 | |
Tejun Heo | ccea34b | 2009-03-07 00:44:13 +0900 | [diff] [blame] | 1048 | mutex_lock(&pcpu_alloc_mutex); |
| 1049 | spin_lock_irq(&pcpu_lock); |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 1050 | |
Tejun Heo | edcb463 | 2009-03-06 14:33:59 +0900 | [diff] [blame] | 1051 | /* serve reserved allocations from the reserved chunk if available */ |
| 1052 | if (reserved && pcpu_reserved_chunk) { |
| 1053 | chunk = pcpu_reserved_chunk; |
Tejun Heo | 9f7dcf2 | 2009-03-07 00:44:09 +0900 | [diff] [blame] | 1054 | if (size > chunk->contig_hint || |
| 1055 | pcpu_extend_area_map(chunk) < 0) |
Tejun Heo | ccea34b | 2009-03-07 00:44:13 +0900 | [diff] [blame] | 1056 | goto fail_unlock; |
Tejun Heo | edcb463 | 2009-03-06 14:33:59 +0900 | [diff] [blame] | 1057 | off = pcpu_alloc_area(chunk, size, align); |
| 1058 | if (off >= 0) |
| 1059 | goto area_found; |
Tejun Heo | ccea34b | 2009-03-07 00:44:13 +0900 | [diff] [blame] | 1060 | goto fail_unlock; |
Tejun Heo | edcb463 | 2009-03-06 14:33:59 +0900 | [diff] [blame] | 1061 | } |
| 1062 | |
Tejun Heo | ccea34b | 2009-03-07 00:44:13 +0900 | [diff] [blame] | 1063 | restart: |
Tejun Heo | edcb463 | 2009-03-06 14:33:59 +0900 | [diff] [blame] | 1064 | /* search through normal chunks */ |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 1065 | for (slot = pcpu_size_to_slot(size); slot < pcpu_nr_slots; slot++) { |
| 1066 | list_for_each_entry(chunk, &pcpu_slot[slot], list) { |
| 1067 | if (size > chunk->contig_hint) |
| 1068 | continue; |
Tejun Heo | ccea34b | 2009-03-07 00:44:13 +0900 | [diff] [blame] | 1069 | |
| 1070 | switch (pcpu_extend_area_map(chunk)) { |
| 1071 | case 0: |
| 1072 | break; |
| 1073 | case 1: |
| 1074 | goto restart; /* pcpu_lock dropped, restart */ |
| 1075 | default: |
| 1076 | goto fail_unlock; |
| 1077 | } |
| 1078 | |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 1079 | off = pcpu_alloc_area(chunk, size, align); |
| 1080 | if (off >= 0) |
| 1081 | goto area_found; |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 1082 | } |
| 1083 | } |
| 1084 | |
| 1085 | /* hmmm... no space left, create a new chunk */ |
Tejun Heo | ccea34b | 2009-03-07 00:44:13 +0900 | [diff] [blame] | 1086 | spin_unlock_irq(&pcpu_lock); |
| 1087 | |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 1088 | chunk = alloc_pcpu_chunk(); |
| 1089 | if (!chunk) |
Tejun Heo | ccea34b | 2009-03-07 00:44:13 +0900 | [diff] [blame] | 1090 | goto fail_unlock_mutex; |
| 1091 | |
| 1092 | spin_lock_irq(&pcpu_lock); |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 1093 | pcpu_chunk_relocate(chunk, -1); |
Tejun Heo | ccea34b | 2009-03-07 00:44:13 +0900 | [diff] [blame] | 1094 | goto restart; |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 1095 | |
| 1096 | area_found: |
Tejun Heo | ccea34b | 2009-03-07 00:44:13 +0900 | [diff] [blame] | 1097 | spin_unlock_irq(&pcpu_lock); |
| 1098 | |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 1099 | /* populate, map and clear the area */ |
| 1100 | if (pcpu_populate_chunk(chunk, off, size)) { |
Tejun Heo | ccea34b | 2009-03-07 00:44:13 +0900 | [diff] [blame] | 1101 | spin_lock_irq(&pcpu_lock); |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 1102 | pcpu_free_area(chunk, off); |
Tejun Heo | ccea34b | 2009-03-07 00:44:13 +0900 | [diff] [blame] | 1103 | goto fail_unlock; |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 1104 | } |
| 1105 | |
Tejun Heo | ccea34b | 2009-03-07 00:44:13 +0900 | [diff] [blame] | 1106 | mutex_unlock(&pcpu_alloc_mutex); |
| 1107 | |
Tejun Heo | bba174f | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1108 | /* return address relative to base address */ |
| 1109 | return __addr_to_pcpu_ptr(chunk->base_addr + off); |
Tejun Heo | ccea34b | 2009-03-07 00:44:13 +0900 | [diff] [blame] | 1110 | |
| 1111 | fail_unlock: |
| 1112 | spin_unlock_irq(&pcpu_lock); |
| 1113 | fail_unlock_mutex: |
| 1114 | mutex_unlock(&pcpu_alloc_mutex); |
| 1115 | return NULL; |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 1116 | } |
Tejun Heo | edcb463 | 2009-03-06 14:33:59 +0900 | [diff] [blame] | 1117 | |
| 1118 | /** |
| 1119 | * __alloc_percpu - allocate dynamic percpu area |
| 1120 | * @size: size of area to allocate in bytes |
| 1121 | * @align: alignment of area (max PAGE_SIZE) |
| 1122 | * |
| 1123 | * Allocate percpu area of @size bytes aligned at @align. Might |
| 1124 | * sleep. Might trigger writeouts. |
| 1125 | * |
Tejun Heo | ccea34b | 2009-03-07 00:44:13 +0900 | [diff] [blame] | 1126 | * CONTEXT: |
| 1127 | * Does GFP_KERNEL allocation. |
| 1128 | * |
Tejun Heo | edcb463 | 2009-03-06 14:33:59 +0900 | [diff] [blame] | 1129 | * RETURNS: |
| 1130 | * Percpu pointer to the allocated area on success, NULL on failure. |
| 1131 | */ |
| 1132 | void *__alloc_percpu(size_t size, size_t align) |
| 1133 | { |
| 1134 | return pcpu_alloc(size, align, false); |
| 1135 | } |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 1136 | EXPORT_SYMBOL_GPL(__alloc_percpu); |
| 1137 | |
Tejun Heo | edcb463 | 2009-03-06 14:33:59 +0900 | [diff] [blame] | 1138 | /** |
| 1139 | * __alloc_reserved_percpu - allocate reserved percpu area |
| 1140 | * @size: size of area to allocate in bytes |
| 1141 | * @align: alignment of area (max PAGE_SIZE) |
| 1142 | * |
| 1143 | * Allocate percpu area of @size bytes aligned at @align from reserved |
| 1144 | * percpu area if arch has set it up; otherwise, allocation is served |
| 1145 | * from the same dynamic area. Might sleep. Might trigger writeouts. |
| 1146 | * |
Tejun Heo | ccea34b | 2009-03-07 00:44:13 +0900 | [diff] [blame] | 1147 | * CONTEXT: |
| 1148 | * Does GFP_KERNEL allocation. |
| 1149 | * |
Tejun Heo | edcb463 | 2009-03-06 14:33:59 +0900 | [diff] [blame] | 1150 | * RETURNS: |
| 1151 | * Percpu pointer to the allocated area on success, NULL on failure. |
| 1152 | */ |
| 1153 | void *__alloc_reserved_percpu(size_t size, size_t align) |
| 1154 | { |
| 1155 | return pcpu_alloc(size, align, true); |
| 1156 | } |
| 1157 | |
Tejun Heo | a56dbdd | 2009-03-07 00:44:11 +0900 | [diff] [blame] | 1158 | /** |
| 1159 | * pcpu_reclaim - reclaim fully free chunks, workqueue function |
| 1160 | * @work: unused |
| 1161 | * |
| 1162 | * Reclaim all fully free chunks except for the first one. |
Tejun Heo | ccea34b | 2009-03-07 00:44:13 +0900 | [diff] [blame] | 1163 | * |
| 1164 | * CONTEXT: |
| 1165 | * workqueue context. |
Tejun Heo | a56dbdd | 2009-03-07 00:44:11 +0900 | [diff] [blame] | 1166 | */ |
| 1167 | static void pcpu_reclaim(struct work_struct *work) |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 1168 | { |
Tejun Heo | a56dbdd | 2009-03-07 00:44:11 +0900 | [diff] [blame] | 1169 | LIST_HEAD(todo); |
| 1170 | struct list_head *head = &pcpu_slot[pcpu_nr_slots - 1]; |
| 1171 | struct pcpu_chunk *chunk, *next; |
| 1172 | |
Tejun Heo | ccea34b | 2009-03-07 00:44:13 +0900 | [diff] [blame] | 1173 | mutex_lock(&pcpu_alloc_mutex); |
| 1174 | spin_lock_irq(&pcpu_lock); |
Tejun Heo | a56dbdd | 2009-03-07 00:44:11 +0900 | [diff] [blame] | 1175 | |
| 1176 | list_for_each_entry_safe(chunk, next, head, list) { |
| 1177 | WARN_ON(chunk->immutable); |
| 1178 | |
| 1179 | /* spare the first one */ |
| 1180 | if (chunk == list_first_entry(head, struct pcpu_chunk, list)) |
| 1181 | continue; |
| 1182 | |
Tejun Heo | a56dbdd | 2009-03-07 00:44:11 +0900 | [diff] [blame] | 1183 | list_move(&chunk->list, &todo); |
| 1184 | } |
| 1185 | |
Tejun Heo | ccea34b | 2009-03-07 00:44:13 +0900 | [diff] [blame] | 1186 | spin_unlock_irq(&pcpu_lock); |
Tejun Heo | a56dbdd | 2009-03-07 00:44:11 +0900 | [diff] [blame] | 1187 | |
| 1188 | list_for_each_entry_safe(chunk, next, &todo, list) { |
Tejun Heo | ce3141a | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 1189 | pcpu_depopulate_chunk(chunk, 0, pcpu_unit_size); |
Tejun Heo | a56dbdd | 2009-03-07 00:44:11 +0900 | [diff] [blame] | 1190 | free_pcpu_chunk(chunk); |
| 1191 | } |
Tejun Heo | 971f391 | 2009-08-14 15:00:49 +0900 | [diff] [blame] | 1192 | |
| 1193 | mutex_unlock(&pcpu_alloc_mutex); |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 1194 | } |
| 1195 | |
| 1196 | /** |
| 1197 | * free_percpu - free percpu area |
| 1198 | * @ptr: pointer to area to free |
| 1199 | * |
Tejun Heo | ccea34b | 2009-03-07 00:44:13 +0900 | [diff] [blame] | 1200 | * Free percpu area @ptr. |
| 1201 | * |
| 1202 | * CONTEXT: |
| 1203 | * Can be called from atomic context. |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 1204 | */ |
| 1205 | void free_percpu(void *ptr) |
| 1206 | { |
| 1207 | void *addr = __pcpu_ptr_to_addr(ptr); |
| 1208 | struct pcpu_chunk *chunk; |
Tejun Heo | ccea34b | 2009-03-07 00:44:13 +0900 | [diff] [blame] | 1209 | unsigned long flags; |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 1210 | int off; |
| 1211 | |
| 1212 | if (!ptr) |
| 1213 | return; |
| 1214 | |
Tejun Heo | ccea34b | 2009-03-07 00:44:13 +0900 | [diff] [blame] | 1215 | spin_lock_irqsave(&pcpu_lock, flags); |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 1216 | |
| 1217 | chunk = pcpu_chunk_addr_search(addr); |
Tejun Heo | bba174f | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1218 | off = addr - chunk->base_addr; |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 1219 | |
| 1220 | pcpu_free_area(chunk, off); |
| 1221 | |
Tejun Heo | a56dbdd | 2009-03-07 00:44:11 +0900 | [diff] [blame] | 1222 | /* if there are more than one fully free chunks, wake up grim reaper */ |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 1223 | if (chunk->free_size == pcpu_unit_size) { |
| 1224 | struct pcpu_chunk *pos; |
| 1225 | |
Tejun Heo | a56dbdd | 2009-03-07 00:44:11 +0900 | [diff] [blame] | 1226 | list_for_each_entry(pos, &pcpu_slot[pcpu_nr_slots - 1], list) |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 1227 | if (pos != chunk) { |
Tejun Heo | a56dbdd | 2009-03-07 00:44:11 +0900 | [diff] [blame] | 1228 | schedule_work(&pcpu_reclaim_work); |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 1229 | break; |
| 1230 | } |
| 1231 | } |
| 1232 | |
Tejun Heo | ccea34b | 2009-03-07 00:44:13 +0900 | [diff] [blame] | 1233 | spin_unlock_irqrestore(&pcpu_lock, flags); |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 1234 | } |
| 1235 | EXPORT_SYMBOL_GPL(free_percpu); |
| 1236 | |
Tejun Heo | 033e48f | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1237 | static inline size_t pcpu_calc_fc_sizes(size_t static_size, |
| 1238 | size_t reserved_size, |
| 1239 | ssize_t *dyn_sizep) |
| 1240 | { |
| 1241 | size_t size_sum; |
| 1242 | |
| 1243 | size_sum = PFN_ALIGN(static_size + reserved_size + |
| 1244 | (*dyn_sizep >= 0 ? *dyn_sizep : 0)); |
| 1245 | if (*dyn_sizep != 0) |
| 1246 | *dyn_sizep = size_sum - static_size - reserved_size; |
| 1247 | |
| 1248 | return size_sum; |
| 1249 | } |
| 1250 | |
Tejun Heo | 033e48f | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1251 | /** |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1252 | * pcpu_alloc_alloc_info - allocate percpu allocation info |
| 1253 | * @nr_groups: the number of groups |
| 1254 | * @nr_units: the number of units |
Tejun Heo | 033e48f | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1255 | * |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1256 | * Allocate ai which is large enough for @nr_groups groups containing |
| 1257 | * @nr_units units. The returned ai's groups[0].cpu_map points to the |
| 1258 | * cpu_map array which is long enough for @nr_units and filled with |
| 1259 | * NR_CPUS. It's the caller's responsibility to initialize cpu_map |
| 1260 | * pointer of other groups. |
Tejun Heo | 033e48f | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1261 | * |
| 1262 | * RETURNS: |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1263 | * Pointer to the allocated pcpu_alloc_info on success, NULL on |
| 1264 | * failure. |
Tejun Heo | 033e48f | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1265 | */ |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1266 | struct pcpu_alloc_info * __init pcpu_alloc_alloc_info(int nr_groups, |
| 1267 | int nr_units) |
| 1268 | { |
| 1269 | struct pcpu_alloc_info *ai; |
| 1270 | size_t base_size, ai_size; |
| 1271 | void *ptr; |
| 1272 | int unit; |
| 1273 | |
| 1274 | base_size = ALIGN(sizeof(*ai) + nr_groups * sizeof(ai->groups[0]), |
| 1275 | __alignof__(ai->groups[0].cpu_map[0])); |
| 1276 | ai_size = base_size + nr_units * sizeof(ai->groups[0].cpu_map[0]); |
| 1277 | |
| 1278 | ptr = alloc_bootmem_nopanic(PFN_ALIGN(ai_size)); |
| 1279 | if (!ptr) |
| 1280 | return NULL; |
| 1281 | ai = ptr; |
| 1282 | ptr += base_size; |
| 1283 | |
| 1284 | ai->groups[0].cpu_map = ptr; |
| 1285 | |
| 1286 | for (unit = 0; unit < nr_units; unit++) |
| 1287 | ai->groups[0].cpu_map[unit] = NR_CPUS; |
| 1288 | |
| 1289 | ai->nr_groups = nr_groups; |
| 1290 | ai->__ai_size = PFN_ALIGN(ai_size); |
| 1291 | |
| 1292 | return ai; |
| 1293 | } |
| 1294 | |
| 1295 | /** |
| 1296 | * pcpu_free_alloc_info - free percpu allocation info |
| 1297 | * @ai: pcpu_alloc_info to free |
| 1298 | * |
| 1299 | * Free @ai which was allocated by pcpu_alloc_alloc_info(). |
| 1300 | */ |
| 1301 | void __init pcpu_free_alloc_info(struct pcpu_alloc_info *ai) |
| 1302 | { |
| 1303 | free_bootmem(__pa(ai), ai->__ai_size); |
| 1304 | } |
| 1305 | |
| 1306 | /** |
| 1307 | * pcpu_build_alloc_info - build alloc_info considering distances between CPUs |
| 1308 | * @reserved_size: the size of reserved percpu area in bytes |
| 1309 | * @dyn_size: free size for dynamic allocation in bytes, -1 for auto |
| 1310 | * @atom_size: allocation atom size |
| 1311 | * @cpu_distance_fn: callback to determine distance between cpus, optional |
| 1312 | * |
| 1313 | * This function determines grouping of units, their mappings to cpus |
| 1314 | * and other parameters considering needed percpu size, allocation |
| 1315 | * atom size and distances between CPUs. |
| 1316 | * |
| 1317 | * Groups are always mutliples of atom size and CPUs which are of |
| 1318 | * LOCAL_DISTANCE both ways are grouped together and share space for |
| 1319 | * units in the same group. The returned configuration is guaranteed |
| 1320 | * to have CPUs on different nodes on different groups and >=75% usage |
| 1321 | * of allocated virtual address space. |
| 1322 | * |
| 1323 | * RETURNS: |
| 1324 | * On success, pointer to the new allocation_info is returned. On |
| 1325 | * failure, ERR_PTR value is returned. |
| 1326 | */ |
| 1327 | struct pcpu_alloc_info * __init pcpu_build_alloc_info( |
| 1328 | size_t reserved_size, ssize_t dyn_size, |
| 1329 | size_t atom_size, |
| 1330 | pcpu_fc_cpu_distance_fn_t cpu_distance_fn) |
Tejun Heo | 033e48f | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1331 | { |
| 1332 | static int group_map[NR_CPUS] __initdata; |
| 1333 | static int group_cnt[NR_CPUS] __initdata; |
| 1334 | const size_t static_size = __per_cpu_end - __per_cpu_start; |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1335 | int group_cnt_max = 0, nr_groups = 1, nr_units = 0; |
Tejun Heo | 033e48f | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1336 | size_t size_sum, min_unit_size, alloc_size; |
| 1337 | int upa, max_upa, uninitialized_var(best_upa); /* units_per_alloc */ |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1338 | int last_allocs, group, unit; |
Tejun Heo | 033e48f | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1339 | unsigned int cpu, tcpu; |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1340 | struct pcpu_alloc_info *ai; |
| 1341 | unsigned int *cpu_map; |
Tejun Heo | 033e48f | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1342 | |
| 1343 | /* |
| 1344 | * Determine min_unit_size, alloc_size and max_upa such that |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1345 | * alloc_size is multiple of atom_size and is the smallest |
Tejun Heo | 033e48f | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1346 | * which can accomodate 4k aligned segments which are equal to |
| 1347 | * or larger than min_unit_size. |
| 1348 | */ |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1349 | size_sum = pcpu_calc_fc_sizes(static_size, reserved_size, &dyn_size); |
Tejun Heo | 033e48f | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1350 | min_unit_size = max_t(size_t, size_sum, PCPU_MIN_UNIT_SIZE); |
| 1351 | |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1352 | alloc_size = roundup(min_unit_size, atom_size); |
Tejun Heo | 033e48f | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1353 | upa = alloc_size / min_unit_size; |
| 1354 | while (alloc_size % upa || ((alloc_size / upa) & ~PAGE_MASK)) |
| 1355 | upa--; |
| 1356 | max_upa = upa; |
| 1357 | |
| 1358 | /* group cpus according to their proximity */ |
| 1359 | for_each_possible_cpu(cpu) { |
| 1360 | group = 0; |
| 1361 | next_group: |
| 1362 | for_each_possible_cpu(tcpu) { |
| 1363 | if (cpu == tcpu) |
| 1364 | break; |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1365 | if (group_map[tcpu] == group && cpu_distance_fn && |
Tejun Heo | 033e48f | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1366 | (cpu_distance_fn(cpu, tcpu) > LOCAL_DISTANCE || |
| 1367 | cpu_distance_fn(tcpu, cpu) > LOCAL_DISTANCE)) { |
| 1368 | group++; |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1369 | nr_groups = max(nr_groups, group + 1); |
Tejun Heo | 033e48f | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1370 | goto next_group; |
| 1371 | } |
| 1372 | } |
| 1373 | group_map[cpu] = group; |
| 1374 | group_cnt[group]++; |
| 1375 | group_cnt_max = max(group_cnt_max, group_cnt[group]); |
| 1376 | } |
| 1377 | |
| 1378 | /* |
| 1379 | * Expand unit size until address space usage goes over 75% |
| 1380 | * and then as much as possible without using more address |
| 1381 | * space. |
| 1382 | */ |
| 1383 | last_allocs = INT_MAX; |
| 1384 | for (upa = max_upa; upa; upa--) { |
| 1385 | int allocs = 0, wasted = 0; |
| 1386 | |
| 1387 | if (alloc_size % upa || ((alloc_size / upa) & ~PAGE_MASK)) |
| 1388 | continue; |
| 1389 | |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1390 | for (group = 0; group < nr_groups; group++) { |
Tejun Heo | 033e48f | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1391 | int this_allocs = DIV_ROUND_UP(group_cnt[group], upa); |
| 1392 | allocs += this_allocs; |
| 1393 | wasted += this_allocs * upa - group_cnt[group]; |
| 1394 | } |
| 1395 | |
| 1396 | /* |
| 1397 | * Don't accept if wastage is over 25%. The |
| 1398 | * greater-than comparison ensures upa==1 always |
| 1399 | * passes the following check. |
| 1400 | */ |
| 1401 | if (wasted > num_possible_cpus() / 3) |
| 1402 | continue; |
| 1403 | |
| 1404 | /* and then don't consume more memory */ |
| 1405 | if (allocs > last_allocs) |
| 1406 | break; |
| 1407 | last_allocs = allocs; |
| 1408 | best_upa = upa; |
| 1409 | } |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1410 | upa = best_upa; |
Tejun Heo | 033e48f | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1411 | |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1412 | /* allocate and fill alloc_info */ |
| 1413 | for (group = 0; group < nr_groups; group++) |
| 1414 | nr_units += roundup(group_cnt[group], upa); |
| 1415 | |
| 1416 | ai = pcpu_alloc_alloc_info(nr_groups, nr_units); |
| 1417 | if (!ai) |
| 1418 | return ERR_PTR(-ENOMEM); |
| 1419 | cpu_map = ai->groups[0].cpu_map; |
| 1420 | |
| 1421 | for (group = 0; group < nr_groups; group++) { |
| 1422 | ai->groups[group].cpu_map = cpu_map; |
| 1423 | cpu_map += roundup(group_cnt[group], upa); |
Tejun Heo | 033e48f | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1424 | } |
| 1425 | |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1426 | ai->static_size = static_size; |
| 1427 | ai->reserved_size = reserved_size; |
| 1428 | ai->dyn_size = dyn_size; |
| 1429 | ai->unit_size = alloc_size / upa; |
| 1430 | ai->atom_size = atom_size; |
| 1431 | ai->alloc_size = alloc_size; |
| 1432 | |
| 1433 | for (group = 0, unit = 0; group_cnt[group]; group++) { |
| 1434 | struct pcpu_group_info *gi = &ai->groups[group]; |
| 1435 | |
| 1436 | /* |
| 1437 | * Initialize base_offset as if all groups are located |
| 1438 | * back-to-back. The caller should update this to |
| 1439 | * reflect actual allocation. |
| 1440 | */ |
| 1441 | gi->base_offset = unit * ai->unit_size; |
| 1442 | |
| 1443 | for_each_possible_cpu(cpu) |
| 1444 | if (group_map[cpu] == group) |
| 1445 | gi->cpu_map[gi->nr_units++] = cpu; |
| 1446 | gi->nr_units = roundup(gi->nr_units, upa); |
| 1447 | unit += gi->nr_units; |
| 1448 | } |
| 1449 | BUG_ON(unit != nr_units); |
| 1450 | |
| 1451 | return ai; |
Tejun Heo | 033e48f | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1452 | } |
| 1453 | |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1454 | /** |
| 1455 | * pcpu_dump_alloc_info - print out information about pcpu_alloc_info |
| 1456 | * @lvl: loglevel |
| 1457 | * @ai: allocation info to dump |
| 1458 | * |
| 1459 | * Print out information about @ai using loglevel @lvl. |
| 1460 | */ |
| 1461 | static void pcpu_dump_alloc_info(const char *lvl, |
| 1462 | const struct pcpu_alloc_info *ai) |
Tejun Heo | 033e48f | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1463 | { |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1464 | int group_width = 1, cpu_width = 1, width; |
Tejun Heo | 033e48f | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1465 | char empty_str[] = "--------"; |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1466 | int alloc = 0, alloc_end = 0; |
| 1467 | int group, v; |
| 1468 | int upa, apl; /* units per alloc, allocs per line */ |
Tejun Heo | 033e48f | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1469 | |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1470 | v = ai->nr_groups; |
Tejun Heo | 033e48f | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1471 | while (v /= 10) |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1472 | group_width++; |
Tejun Heo | 033e48f | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1473 | |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1474 | v = num_possible_cpus(); |
| 1475 | while (v /= 10) |
| 1476 | cpu_width++; |
| 1477 | empty_str[min_t(int, cpu_width, sizeof(empty_str) - 1)] = '\0'; |
Tejun Heo | 033e48f | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1478 | |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1479 | upa = ai->alloc_size / ai->unit_size; |
| 1480 | width = upa * (cpu_width + 1) + group_width + 3; |
| 1481 | apl = rounddown_pow_of_two(max(60 / width, 1)); |
Tejun Heo | 033e48f | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1482 | |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1483 | printk("%spcpu-alloc: s%zu r%zu d%zu u%zu alloc=%zu*%zu", |
| 1484 | lvl, ai->static_size, ai->reserved_size, ai->dyn_size, |
| 1485 | ai->unit_size, ai->alloc_size / ai->atom_size, ai->atom_size); |
| 1486 | |
| 1487 | for (group = 0; group < ai->nr_groups; group++) { |
| 1488 | const struct pcpu_group_info *gi = &ai->groups[group]; |
| 1489 | int unit = 0, unit_end = 0; |
| 1490 | |
| 1491 | BUG_ON(gi->nr_units % upa); |
| 1492 | for (alloc_end += gi->nr_units / upa; |
| 1493 | alloc < alloc_end; alloc++) { |
| 1494 | if (!(alloc % apl)) { |
Tejun Heo | 033e48f | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1495 | printk("\n"); |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1496 | printk("%spcpu-alloc: ", lvl); |
| 1497 | } |
| 1498 | printk("[%0*d] ", group_width, group); |
| 1499 | |
| 1500 | for (unit_end += upa; unit < unit_end; unit++) |
| 1501 | if (gi->cpu_map[unit] != NR_CPUS) |
| 1502 | printk("%0*d ", cpu_width, |
| 1503 | gi->cpu_map[unit]); |
| 1504 | else |
| 1505 | printk("%s ", empty_str); |
Tejun Heo | 033e48f | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1506 | } |
Tejun Heo | 033e48f | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1507 | } |
| 1508 | printk("\n"); |
| 1509 | } |
Tejun Heo | 033e48f | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1510 | |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 1511 | /** |
Tejun Heo | 8d408b4 | 2009-02-24 11:57:21 +0900 | [diff] [blame] | 1512 | * pcpu_setup_first_chunk - initialize the first percpu chunk |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1513 | * @ai: pcpu_alloc_info describing how to percpu area is shaped |
Tejun Heo | 38a6be5 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 1514 | * @base_addr: mapped address |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 1515 | * |
Tejun Heo | 8d408b4 | 2009-02-24 11:57:21 +0900 | [diff] [blame] | 1516 | * Initialize the first percpu chunk which contains the kernel static |
| 1517 | * perpcu area. This function is to be called from arch percpu area |
Tejun Heo | 38a6be5 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 1518 | * setup path. |
Tejun Heo | 8d408b4 | 2009-02-24 11:57:21 +0900 | [diff] [blame] | 1519 | * |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1520 | * @ai contains all information necessary to initialize the first |
| 1521 | * chunk and prime the dynamic percpu allocator. |
| 1522 | * |
| 1523 | * @ai->static_size is the size of static percpu area. |
| 1524 | * |
| 1525 | * @ai->reserved_size, if non-zero, specifies the amount of bytes to |
Tejun Heo | edcb463 | 2009-03-06 14:33:59 +0900 | [diff] [blame] | 1526 | * reserve after the static area in the first chunk. This reserves |
| 1527 | * the first chunk such that it's available only through reserved |
| 1528 | * percpu allocation. This is primarily used to serve module percpu |
| 1529 | * static areas on architectures where the addressing model has |
| 1530 | * limited offset range for symbol relocations to guarantee module |
| 1531 | * percpu symbols fall inside the relocatable range. |
| 1532 | * |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1533 | * @ai->dyn_size determines the number of bytes available for dynamic |
| 1534 | * allocation in the first chunk. The area between @ai->static_size + |
| 1535 | * @ai->reserved_size + @ai->dyn_size and @ai->unit_size is unused. |
Tejun Heo | 6074d5b | 2009-03-10 16:27:48 +0900 | [diff] [blame] | 1536 | * |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1537 | * @ai->unit_size specifies unit size and must be aligned to PAGE_SIZE |
| 1538 | * and equal to or larger than @ai->static_size + @ai->reserved_size + |
| 1539 | * @ai->dyn_size. |
| 1540 | * |
| 1541 | * @ai->atom_size is the allocation atom size and used as alignment |
| 1542 | * for vm areas. |
| 1543 | * |
| 1544 | * @ai->alloc_size is the allocation size and always multiple of |
| 1545 | * @ai->atom_size. This is larger than @ai->atom_size if |
| 1546 | * @ai->unit_size is larger than @ai->atom_size. |
| 1547 | * |
| 1548 | * @ai->nr_groups and @ai->groups describe virtual memory layout of |
| 1549 | * percpu areas. Units which should be colocated are put into the |
| 1550 | * same group. Dynamic VM areas will be allocated according to these |
| 1551 | * groupings. If @ai->nr_groups is zero, a single group containing |
| 1552 | * all units is assumed. |
Tejun Heo | 8d408b4 | 2009-02-24 11:57:21 +0900 | [diff] [blame] | 1553 | * |
Tejun Heo | 38a6be5 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 1554 | * The caller should have mapped the first chunk at @base_addr and |
| 1555 | * copied static data to each unit. |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 1556 | * |
Tejun Heo | edcb463 | 2009-03-06 14:33:59 +0900 | [diff] [blame] | 1557 | * If the first chunk ends up with both reserved and dynamic areas, it |
| 1558 | * is served by two chunks - one to serve the core static and reserved |
| 1559 | * areas and the other for the dynamic area. They share the same vm |
| 1560 | * and page map but uses different area allocation map to stay away |
| 1561 | * from each other. The latter chunk is circulated in the chunk slots |
| 1562 | * and available for dynamic allocation like any other chunks. |
| 1563 | * |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 1564 | * RETURNS: |
Tejun Heo | fb435d5 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1565 | * 0 on success, -errno on failure. |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 1566 | */ |
Tejun Heo | fb435d5 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1567 | int __init pcpu_setup_first_chunk(const struct pcpu_alloc_info *ai, |
| 1568 | void *base_addr) |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 1569 | { |
Tejun Heo | edcb463 | 2009-03-06 14:33:59 +0900 | [diff] [blame] | 1570 | static int smap[2], dmap[2]; |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1571 | size_t dyn_size = ai->dyn_size; |
| 1572 | size_t size_sum = ai->static_size + ai->reserved_size + dyn_size; |
Tejun Heo | edcb463 | 2009-03-06 14:33:59 +0900 | [diff] [blame] | 1573 | struct pcpu_chunk *schunk, *dchunk = NULL; |
Tejun Heo | fb435d5 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1574 | unsigned long *unit_off; |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1575 | unsigned int cpu; |
| 1576 | int *unit_map; |
| 1577 | int group, unit, i; |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 1578 | |
Tejun Heo | 2f39e63 | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 1579 | /* sanity checks */ |
Tejun Heo | edcb463 | 2009-03-06 14:33:59 +0900 | [diff] [blame] | 1580 | BUILD_BUG_ON(ARRAY_SIZE(smap) >= PCPU_DFL_MAP_ALLOC || |
| 1581 | ARRAY_SIZE(dmap) >= PCPU_DFL_MAP_ALLOC); |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1582 | BUG_ON(ai->nr_groups <= 0); |
| 1583 | BUG_ON(!ai->static_size); |
Tejun Heo | 38a6be5 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 1584 | BUG_ON(!base_addr); |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1585 | BUG_ON(ai->unit_size < size_sum); |
| 1586 | BUG_ON(ai->unit_size & ~PAGE_MASK); |
| 1587 | BUG_ON(ai->unit_size < PCPU_MIN_UNIT_SIZE); |
| 1588 | |
| 1589 | pcpu_dump_alloc_info(KERN_DEBUG, ai); |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 1590 | |
Tejun Heo | fb435d5 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1591 | /* determine number of units and initialize unit_map and base */ |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1592 | unit_map = alloc_bootmem(nr_cpu_ids * sizeof(unit_map[0])); |
Tejun Heo | fb435d5 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1593 | unit_off = alloc_bootmem(nr_cpu_ids * sizeof(unit_off[0])); |
Tejun Heo | 2f39e63 | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 1594 | |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1595 | for (cpu = 0; cpu < nr_cpu_ids; cpu++) |
| 1596 | unit_map[cpu] = NR_CPUS; |
| 1597 | pcpu_first_unit_cpu = NR_CPUS; |
Tejun Heo | 2f39e63 | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 1598 | |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1599 | for (group = 0, unit = 0; group < ai->nr_groups; group++, unit += i) { |
| 1600 | const struct pcpu_group_info *gi = &ai->groups[group]; |
Tejun Heo | 2f39e63 | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 1601 | |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1602 | for (i = 0; i < gi->nr_units; i++) { |
| 1603 | cpu = gi->cpu_map[i]; |
| 1604 | if (cpu == NR_CPUS) |
| 1605 | continue; |
| 1606 | |
| 1607 | BUG_ON(cpu > nr_cpu_ids || !cpu_possible(cpu)); |
| 1608 | BUG_ON(unit_map[cpu] != NR_CPUS); |
| 1609 | |
| 1610 | unit_map[cpu] = unit + i; |
Tejun Heo | fb435d5 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1611 | unit_off[cpu] = gi->base_offset + i * ai->unit_size; |
| 1612 | |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1613 | if (pcpu_first_unit_cpu == NR_CPUS) |
Tejun Heo | 2f39e63 | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 1614 | pcpu_first_unit_cpu = cpu; |
Tejun Heo | 2f39e63 | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 1615 | } |
Tejun Heo | 2f39e63 | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 1616 | } |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1617 | pcpu_last_unit_cpu = cpu; |
| 1618 | pcpu_nr_units = unit; |
| 1619 | |
| 1620 | for_each_possible_cpu(cpu) |
| 1621 | BUG_ON(unit_map[cpu] == NR_CPUS); |
| 1622 | |
| 1623 | pcpu_unit_map = unit_map; |
Tejun Heo | fb435d5 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1624 | pcpu_unit_offsets = unit_off; |
Tejun Heo | 2f39e63 | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 1625 | |
| 1626 | /* determine basic parameters */ |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1627 | pcpu_unit_pages = ai->unit_size >> PAGE_SHIFT; |
Tejun Heo | d9b55ee | 2009-02-24 11:57:21 +0900 | [diff] [blame] | 1628 | pcpu_unit_size = pcpu_unit_pages << PAGE_SHIFT; |
Tejun Heo | 2f39e63 | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 1629 | pcpu_chunk_size = pcpu_nr_units * pcpu_unit_size; |
Tejun Heo | ce3141a | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 1630 | pcpu_chunk_struct_size = sizeof(struct pcpu_chunk) + |
| 1631 | BITS_TO_LONGS(pcpu_unit_pages) * sizeof(unsigned long); |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 1632 | |
Tejun Heo | d9b55ee | 2009-02-24 11:57:21 +0900 | [diff] [blame] | 1633 | /* |
| 1634 | * Allocate chunk slots. The additional last slot is for |
| 1635 | * empty chunks. |
| 1636 | */ |
| 1637 | pcpu_nr_slots = __pcpu_size_to_slot(pcpu_unit_size) + 2; |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 1638 | pcpu_slot = alloc_bootmem(pcpu_nr_slots * sizeof(pcpu_slot[0])); |
| 1639 | for (i = 0; i < pcpu_nr_slots; i++) |
| 1640 | INIT_LIST_HEAD(&pcpu_slot[i]); |
| 1641 | |
Tejun Heo | edcb463 | 2009-03-06 14:33:59 +0900 | [diff] [blame] | 1642 | /* |
| 1643 | * Initialize static chunk. If reserved_size is zero, the |
| 1644 | * static chunk covers static area + dynamic allocation area |
| 1645 | * in the first chunk. If reserved_size is not zero, it |
| 1646 | * covers static area + reserved area (mostly used for module |
| 1647 | * static percpu allocation). |
| 1648 | */ |
Tejun Heo | 2441d15 | 2009-03-06 14:33:59 +0900 | [diff] [blame] | 1649 | schunk = alloc_bootmem(pcpu_chunk_struct_size); |
| 1650 | INIT_LIST_HEAD(&schunk->list); |
Tejun Heo | bba174f | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1651 | schunk->base_addr = base_addr; |
Tejun Heo | 61ace7f | 2009-03-06 14:33:59 +0900 | [diff] [blame] | 1652 | schunk->map = smap; |
| 1653 | schunk->map_alloc = ARRAY_SIZE(smap); |
Tejun Heo | 38a6be5 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 1654 | schunk->immutable = true; |
Tejun Heo | ce3141a | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 1655 | bitmap_fill(schunk->populated, pcpu_unit_pages); |
Tejun Heo | edcb463 | 2009-03-06 14:33:59 +0900 | [diff] [blame] | 1656 | |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1657 | if (ai->reserved_size) { |
| 1658 | schunk->free_size = ai->reserved_size; |
Tejun Heo | ae9e6bc | 2009-04-02 13:19:54 +0900 | [diff] [blame] | 1659 | pcpu_reserved_chunk = schunk; |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1660 | pcpu_reserved_chunk_limit = ai->static_size + ai->reserved_size; |
Tejun Heo | edcb463 | 2009-03-06 14:33:59 +0900 | [diff] [blame] | 1661 | } else { |
| 1662 | schunk->free_size = dyn_size; |
| 1663 | dyn_size = 0; /* dynamic area covered */ |
| 1664 | } |
Tejun Heo | 2441d15 | 2009-03-06 14:33:59 +0900 | [diff] [blame] | 1665 | schunk->contig_hint = schunk->free_size; |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 1666 | |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1667 | schunk->map[schunk->map_used++] = -ai->static_size; |
Tejun Heo | 61ace7f | 2009-03-06 14:33:59 +0900 | [diff] [blame] | 1668 | if (schunk->free_size) |
| 1669 | schunk->map[schunk->map_used++] = schunk->free_size; |
| 1670 | |
Tejun Heo | edcb463 | 2009-03-06 14:33:59 +0900 | [diff] [blame] | 1671 | /* init dynamic chunk if necessary */ |
| 1672 | if (dyn_size) { |
Tejun Heo | ce3141a | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 1673 | dchunk = alloc_bootmem(pcpu_chunk_struct_size); |
Tejun Heo | edcb463 | 2009-03-06 14:33:59 +0900 | [diff] [blame] | 1674 | INIT_LIST_HEAD(&dchunk->list); |
Tejun Heo | bba174f | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1675 | dchunk->base_addr = base_addr; |
Tejun Heo | edcb463 | 2009-03-06 14:33:59 +0900 | [diff] [blame] | 1676 | dchunk->map = dmap; |
| 1677 | dchunk->map_alloc = ARRAY_SIZE(dmap); |
Tejun Heo | 38a6be5 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 1678 | dchunk->immutable = true; |
Tejun Heo | ce3141a | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 1679 | bitmap_fill(dchunk->populated, pcpu_unit_pages); |
Tejun Heo | edcb463 | 2009-03-06 14:33:59 +0900 | [diff] [blame] | 1680 | |
| 1681 | dchunk->contig_hint = dchunk->free_size = dyn_size; |
| 1682 | dchunk->map[dchunk->map_used++] = -pcpu_reserved_chunk_limit; |
| 1683 | dchunk->map[dchunk->map_used++] = dchunk->free_size; |
| 1684 | } |
| 1685 | |
Tejun Heo | 2441d15 | 2009-03-06 14:33:59 +0900 | [diff] [blame] | 1686 | /* link the first chunk in */ |
Tejun Heo | ae9e6bc | 2009-04-02 13:19:54 +0900 | [diff] [blame] | 1687 | pcpu_first_chunk = dchunk ?: schunk; |
| 1688 | pcpu_chunk_relocate(pcpu_first_chunk, -1); |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 1689 | |
| 1690 | /* we're done */ |
Tejun Heo | bba174f | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1691 | pcpu_base_addr = base_addr; |
Tejun Heo | fb435d5 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1692 | return 0; |
Tejun Heo | fbf59bc | 2009-02-20 16:29:08 +0900 | [diff] [blame] | 1693 | } |
Tejun Heo | 66c3a75 | 2009-03-10 16:27:48 +0900 | [diff] [blame] | 1694 | |
Tejun Heo | f58dc01 | 2009-08-14 15:00:50 +0900 | [diff] [blame] | 1695 | const char *pcpu_fc_names[PCPU_FC_NR] __initdata = { |
| 1696 | [PCPU_FC_AUTO] = "auto", |
| 1697 | [PCPU_FC_EMBED] = "embed", |
| 1698 | [PCPU_FC_PAGE] = "page", |
| 1699 | [PCPU_FC_LPAGE] = "lpage", |
| 1700 | }; |
| 1701 | |
| 1702 | enum pcpu_fc pcpu_chosen_fc __initdata = PCPU_FC_AUTO; |
| 1703 | |
| 1704 | static int __init percpu_alloc_setup(char *str) |
| 1705 | { |
| 1706 | if (0) |
| 1707 | /* nada */; |
| 1708 | #ifdef CONFIG_NEED_PER_CPU_EMBED_FIRST_CHUNK |
| 1709 | else if (!strcmp(str, "embed")) |
| 1710 | pcpu_chosen_fc = PCPU_FC_EMBED; |
| 1711 | #endif |
| 1712 | #ifdef CONFIG_NEED_PER_CPU_PAGE_FIRST_CHUNK |
| 1713 | else if (!strcmp(str, "page")) |
| 1714 | pcpu_chosen_fc = PCPU_FC_PAGE; |
| 1715 | #endif |
| 1716 | #ifdef CONFIG_NEED_PER_CPU_LPAGE_FIRST_CHUNK |
| 1717 | else if (!strcmp(str, "lpage")) |
| 1718 | pcpu_chosen_fc = PCPU_FC_LPAGE; |
| 1719 | #endif |
| 1720 | else |
| 1721 | pr_warning("PERCPU: unknown allocator %s specified\n", str); |
| 1722 | |
| 1723 | return 0; |
| 1724 | } |
| 1725 | early_param("percpu_alloc", percpu_alloc_setup); |
| 1726 | |
Tejun Heo | 08fc458 | 2009-08-14 15:00:49 +0900 | [diff] [blame] | 1727 | #if defined(CONFIG_NEED_PER_CPU_EMBED_FIRST_CHUNK) || \ |
| 1728 | !defined(CONFIG_HAVE_SETUP_PER_CPU_AREA) |
Tejun Heo | 66c3a75 | 2009-03-10 16:27:48 +0900 | [diff] [blame] | 1729 | /** |
| 1730 | * pcpu_embed_first_chunk - embed the first percpu chunk into bootmem |
Tejun Heo | 66c3a75 | 2009-03-10 16:27:48 +0900 | [diff] [blame] | 1731 | * @reserved_size: the size of reserved percpu area in bytes |
| 1732 | * @dyn_size: free size for dynamic allocation in bytes, -1 for auto |
Tejun Heo | 66c3a75 | 2009-03-10 16:27:48 +0900 | [diff] [blame] | 1733 | * |
| 1734 | * This is a helper to ease setting up embedded first percpu chunk and |
| 1735 | * can be called where pcpu_setup_first_chunk() is expected. |
| 1736 | * |
| 1737 | * If this function is used to setup the first chunk, it is allocated |
| 1738 | * as a contiguous area using bootmem allocator and used as-is without |
| 1739 | * being mapped into vmalloc area. This enables the first chunk to |
| 1740 | * piggy back on the linear physical mapping which often uses larger |
| 1741 | * page size. |
| 1742 | * |
| 1743 | * When @dyn_size is positive, dynamic area might be larger than |
Tejun Heo | 788e5ab | 2009-07-04 08:10:58 +0900 | [diff] [blame] | 1744 | * specified to fill page alignment. When @dyn_size is auto, |
| 1745 | * @dyn_size is just big enough to fill page alignment after static |
| 1746 | * and reserved areas. |
Tejun Heo | 66c3a75 | 2009-03-10 16:27:48 +0900 | [diff] [blame] | 1747 | * |
| 1748 | * If the needed size is smaller than the minimum or specified unit |
| 1749 | * size, the leftover is returned to the bootmem allocator. |
| 1750 | * |
| 1751 | * RETURNS: |
Tejun Heo | fb435d5 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1752 | * 0 on success, -errno on failure. |
Tejun Heo | 66c3a75 | 2009-03-10 16:27:48 +0900 | [diff] [blame] | 1753 | */ |
Tejun Heo | fb435d5 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1754 | int __init pcpu_embed_first_chunk(size_t reserved_size, ssize_t dyn_size) |
Tejun Heo | 66c3a75 | 2009-03-10 16:27:48 +0900 | [diff] [blame] | 1755 | { |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1756 | struct pcpu_alloc_info *ai; |
| 1757 | size_t size_sum, chunk_size; |
Tejun Heo | ce3141a | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 1758 | void *base; |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1759 | int unit; |
Tejun Heo | fb435d5 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1760 | int rc; |
Tejun Heo | 66c3a75 | 2009-03-10 16:27:48 +0900 | [diff] [blame] | 1761 | |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1762 | ai = pcpu_build_alloc_info(reserved_size, dyn_size, PAGE_SIZE, NULL); |
| 1763 | if (IS_ERR(ai)) |
| 1764 | return PTR_ERR(ai); |
| 1765 | BUG_ON(ai->nr_groups != 1); |
| 1766 | BUG_ON(ai->groups[0].nr_units != num_possible_cpus()); |
Tejun Heo | 66c3a75 | 2009-03-10 16:27:48 +0900 | [diff] [blame] | 1767 | |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1768 | size_sum = ai->static_size + ai->reserved_size + ai->dyn_size; |
| 1769 | chunk_size = ai->unit_size * num_possible_cpus(); |
Tejun Heo | fa8a709 | 2009-06-22 11:56:24 +0900 | [diff] [blame] | 1770 | |
Tejun Heo | ce3141a | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 1771 | base = __alloc_bootmem_nopanic(chunk_size, PAGE_SIZE, |
| 1772 | __pa(MAX_DMA_ADDRESS)); |
| 1773 | if (!base) { |
Tejun Heo | fa8a709 | 2009-06-22 11:56:24 +0900 | [diff] [blame] | 1774 | pr_warning("PERCPU: failed to allocate %zu bytes for " |
| 1775 | "embedding\n", chunk_size); |
Tejun Heo | fb435d5 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1776 | rc = -ENOMEM; |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1777 | goto out_free_ai; |
Tejun Heo | fa8a709 | 2009-06-22 11:56:24 +0900 | [diff] [blame] | 1778 | } |
Tejun Heo | 66c3a75 | 2009-03-10 16:27:48 +0900 | [diff] [blame] | 1779 | |
| 1780 | /* return the leftover and copy */ |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1781 | for (unit = 0; unit < num_possible_cpus(); unit++) { |
| 1782 | void *ptr = base + unit * ai->unit_size; |
Tejun Heo | 66c3a75 | 2009-03-10 16:27:48 +0900 | [diff] [blame] | 1783 | |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1784 | free_bootmem(__pa(ptr + size_sum), ai->unit_size - size_sum); |
| 1785 | memcpy(ptr, __per_cpu_load, ai->static_size); |
Tejun Heo | 66c3a75 | 2009-03-10 16:27:48 +0900 | [diff] [blame] | 1786 | } |
| 1787 | |
| 1788 | /* we're ready, commit */ |
Tejun Heo | 004018e | 2009-08-14 15:00:49 +0900 | [diff] [blame] | 1789 | pr_info("PERCPU: Embedded %zu pages/cpu @%p s%zu r%zu d%zu u%zu\n", |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1790 | PFN_DOWN(size_sum), base, ai->static_size, ai->reserved_size, |
| 1791 | ai->dyn_size, ai->unit_size); |
Tejun Heo | 66c3a75 | 2009-03-10 16:27:48 +0900 | [diff] [blame] | 1792 | |
Tejun Heo | fb435d5 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1793 | rc = pcpu_setup_first_chunk(ai, base); |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1794 | out_free_ai: |
| 1795 | pcpu_free_alloc_info(ai); |
Tejun Heo | fb435d5 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1796 | return rc; |
Tejun Heo | d4b95f8 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 1797 | } |
Tejun Heo | 08fc458 | 2009-08-14 15:00:49 +0900 | [diff] [blame] | 1798 | #endif /* CONFIG_NEED_PER_CPU_EMBED_FIRST_CHUNK || |
| 1799 | !CONFIG_HAVE_SETUP_PER_CPU_AREA */ |
Tejun Heo | d4b95f8 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 1800 | |
Tejun Heo | 08fc458 | 2009-08-14 15:00:49 +0900 | [diff] [blame] | 1801 | #ifdef CONFIG_NEED_PER_CPU_PAGE_FIRST_CHUNK |
Tejun Heo | d4b95f8 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 1802 | /** |
Tejun Heo | 00ae406 | 2009-08-14 15:00:49 +0900 | [diff] [blame] | 1803 | * pcpu_page_first_chunk - map the first chunk using PAGE_SIZE pages |
Tejun Heo | d4b95f8 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 1804 | * @reserved_size: the size of reserved percpu area in bytes |
| 1805 | * @alloc_fn: function to allocate percpu page, always called with PAGE_SIZE |
| 1806 | * @free_fn: funtion to free percpu page, always called with PAGE_SIZE |
| 1807 | * @populate_pte_fn: function to populate pte |
| 1808 | * |
Tejun Heo | 00ae406 | 2009-08-14 15:00:49 +0900 | [diff] [blame] | 1809 | * This is a helper to ease setting up page-remapped first percpu |
| 1810 | * chunk and can be called where pcpu_setup_first_chunk() is expected. |
Tejun Heo | d4b95f8 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 1811 | * |
| 1812 | * This is the basic allocator. Static percpu area is allocated |
| 1813 | * page-by-page into vmalloc area. |
| 1814 | * |
| 1815 | * RETURNS: |
Tejun Heo | fb435d5 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1816 | * 0 on success, -errno on failure. |
Tejun Heo | d4b95f8 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 1817 | */ |
Tejun Heo | fb435d5 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1818 | int __init pcpu_page_first_chunk(size_t reserved_size, |
| 1819 | pcpu_fc_alloc_fn_t alloc_fn, |
| 1820 | pcpu_fc_free_fn_t free_fn, |
| 1821 | pcpu_fc_populate_pte_fn_t populate_pte_fn) |
Tejun Heo | d4b95f8 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 1822 | { |
Tejun Heo | 8f05a6a | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 1823 | static struct vm_struct vm; |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1824 | struct pcpu_alloc_info *ai; |
Tejun Heo | 00ae406 | 2009-08-14 15:00:49 +0900 | [diff] [blame] | 1825 | char psize_str[16]; |
Tejun Heo | ce3141a | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 1826 | int unit_pages; |
Tejun Heo | d4b95f8 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 1827 | size_t pages_size; |
Tejun Heo | ce3141a | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 1828 | struct page **pages; |
Tejun Heo | fb435d5 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1829 | int unit, i, j, rc; |
Tejun Heo | d4b95f8 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 1830 | |
Tejun Heo | 00ae406 | 2009-08-14 15:00:49 +0900 | [diff] [blame] | 1831 | snprintf(psize_str, sizeof(psize_str), "%luK", PAGE_SIZE >> 10); |
| 1832 | |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1833 | ai = pcpu_build_alloc_info(reserved_size, -1, PAGE_SIZE, NULL); |
| 1834 | if (IS_ERR(ai)) |
| 1835 | return PTR_ERR(ai); |
| 1836 | BUG_ON(ai->nr_groups != 1); |
| 1837 | BUG_ON(ai->groups[0].nr_units != num_possible_cpus()); |
| 1838 | |
| 1839 | unit_pages = ai->unit_size >> PAGE_SHIFT; |
Tejun Heo | d4b95f8 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 1840 | |
| 1841 | /* unaligned allocations can't be freed, round up to page size */ |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1842 | pages_size = PFN_ALIGN(unit_pages * num_possible_cpus() * |
| 1843 | sizeof(pages[0])); |
Tejun Heo | ce3141a | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 1844 | pages = alloc_bootmem(pages_size); |
Tejun Heo | d4b95f8 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 1845 | |
Tejun Heo | 8f05a6a | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 1846 | /* allocate pages */ |
Tejun Heo | d4b95f8 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 1847 | j = 0; |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1848 | for (unit = 0; unit < num_possible_cpus(); unit++) |
Tejun Heo | ce3141a | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 1849 | for (i = 0; i < unit_pages; i++) { |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1850 | unsigned int cpu = ai->groups[0].cpu_map[unit]; |
Tejun Heo | d4b95f8 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 1851 | void *ptr; |
| 1852 | |
Tejun Heo | 3cbc856 | 2009-08-14 15:00:50 +0900 | [diff] [blame] | 1853 | ptr = alloc_fn(cpu, PAGE_SIZE, PAGE_SIZE); |
Tejun Heo | d4b95f8 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 1854 | if (!ptr) { |
Tejun Heo | 00ae406 | 2009-08-14 15:00:49 +0900 | [diff] [blame] | 1855 | pr_warning("PERCPU: failed to allocate %s page " |
| 1856 | "for cpu%u\n", psize_str, cpu); |
Tejun Heo | d4b95f8 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 1857 | goto enomem; |
| 1858 | } |
Tejun Heo | ce3141a | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 1859 | pages[j++] = virt_to_page(ptr); |
Tejun Heo | d4b95f8 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 1860 | } |
| 1861 | |
Tejun Heo | 8f05a6a | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 1862 | /* allocate vm area, map the pages and copy static data */ |
| 1863 | vm.flags = VM_ALLOC; |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1864 | vm.size = num_possible_cpus() * ai->unit_size; |
Tejun Heo | 8f05a6a | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 1865 | vm_area_register_early(&vm, PAGE_SIZE); |
| 1866 | |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1867 | for (unit = 0; unit < num_possible_cpus(); unit++) { |
Tejun Heo | 1d9d325 | 2009-08-14 15:00:50 +0900 | [diff] [blame] | 1868 | unsigned long unit_addr = |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1869 | (unsigned long)vm.addr + unit * ai->unit_size; |
Tejun Heo | 8f05a6a | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 1870 | |
Tejun Heo | ce3141a | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 1871 | for (i = 0; i < unit_pages; i++) |
Tejun Heo | 8f05a6a | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 1872 | populate_pte_fn(unit_addr + (i << PAGE_SHIFT)); |
| 1873 | |
| 1874 | /* pte already populated, the following shouldn't fail */ |
Tejun Heo | fb435d5 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1875 | rc = __pcpu_map_pages(unit_addr, &pages[unit * unit_pages], |
| 1876 | unit_pages); |
| 1877 | if (rc < 0) |
| 1878 | panic("failed to map percpu area, err=%d\n", rc); |
Tejun Heo | 8f05a6a | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 1879 | |
| 1880 | /* |
| 1881 | * FIXME: Archs with virtual cache should flush local |
| 1882 | * cache for the linear mapping here - something |
| 1883 | * equivalent to flush_cache_vmap() on the local cpu. |
| 1884 | * flush_cache_vmap() can't be used as most supporting |
| 1885 | * data structures are not set up yet. |
| 1886 | */ |
| 1887 | |
| 1888 | /* copy static data */ |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1889 | memcpy((void *)unit_addr, __per_cpu_load, ai->static_size); |
Tejun Heo | 8f05a6a | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 1890 | } |
| 1891 | |
Tejun Heo | d4b95f8 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 1892 | /* we're ready, commit */ |
Tejun Heo | 1d9d325 | 2009-08-14 15:00:50 +0900 | [diff] [blame] | 1893 | pr_info("PERCPU: %d %s pages/cpu @%p s%zu r%zu d%zu\n", |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1894 | unit_pages, psize_str, vm.addr, ai->static_size, |
| 1895 | ai->reserved_size, ai->dyn_size); |
Tejun Heo | d4b95f8 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 1896 | |
Tejun Heo | fb435d5 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1897 | rc = pcpu_setup_first_chunk(ai, vm.addr); |
Tejun Heo | d4b95f8 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 1898 | goto out_free_ar; |
| 1899 | |
| 1900 | enomem: |
| 1901 | while (--j >= 0) |
Tejun Heo | ce3141a | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 1902 | free_fn(page_address(pages[j]), PAGE_SIZE); |
Tejun Heo | fb435d5 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1903 | rc = -ENOMEM; |
Tejun Heo | d4b95f8 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 1904 | out_free_ar: |
Tejun Heo | ce3141a | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 1905 | free_bootmem(__pa(pages), pages_size); |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1906 | pcpu_free_alloc_info(ai); |
Tejun Heo | fb435d5 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1907 | return rc; |
Tejun Heo | d4b95f8 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 1908 | } |
Tejun Heo | 08fc458 | 2009-08-14 15:00:49 +0900 | [diff] [blame] | 1909 | #endif /* CONFIG_NEED_PER_CPU_PAGE_FIRST_CHUNK */ |
Tejun Heo | d4b95f8 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 1910 | |
Tejun Heo | 08fc458 | 2009-08-14 15:00:49 +0900 | [diff] [blame] | 1911 | #ifdef CONFIG_NEED_PER_CPU_LPAGE_FIRST_CHUNK |
Tejun Heo | 8c4bfc6 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 1912 | struct pcpul_ent { |
Tejun Heo | 8c4bfc6 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 1913 | void *ptr; |
Tejun Heo | a530b79 | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 1914 | void *map_addr; |
Tejun Heo | 8c4bfc6 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 1915 | }; |
| 1916 | |
| 1917 | static size_t pcpul_size; |
Tejun Heo | a530b79 | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 1918 | static size_t pcpul_lpage_size; |
| 1919 | static int pcpul_nr_lpages; |
Tejun Heo | 8c4bfc6 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 1920 | static struct pcpul_ent *pcpul_map; |
Tejun Heo | a530b79 | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 1921 | |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1922 | static bool __init pcpul_unit_to_cpu(int unit, const struct pcpu_alloc_info *ai, |
Tejun Heo | a530b79 | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 1923 | unsigned int *cpup) |
| 1924 | { |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1925 | int group, cunit; |
Tejun Heo | a530b79 | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 1926 | |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1927 | for (group = 0, cunit = 0; group < ai->nr_groups; group++) { |
| 1928 | const struct pcpu_group_info *gi = &ai->groups[group]; |
| 1929 | |
| 1930 | if (unit < cunit + gi->nr_units) { |
Tejun Heo | a530b79 | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 1931 | if (cpup) |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1932 | *cpup = gi->cpu_map[unit - cunit]; |
Tejun Heo | a530b79 | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 1933 | return true; |
| 1934 | } |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1935 | cunit += gi->nr_units; |
| 1936 | } |
Tejun Heo | a530b79 | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 1937 | |
| 1938 | return false; |
| 1939 | } |
| 1940 | |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1941 | static int __init pcpul_cpu_to_unit(int cpu, const struct pcpu_alloc_info *ai) |
| 1942 | { |
| 1943 | int group, unit, i; |
| 1944 | |
| 1945 | for (group = 0, unit = 0; group < ai->nr_groups; group++, unit += i) { |
| 1946 | const struct pcpu_group_info *gi = &ai->groups[group]; |
| 1947 | |
| 1948 | for (i = 0; i < gi->nr_units; i++) |
| 1949 | if (gi->cpu_map[i] == cpu) |
| 1950 | return unit + i; |
| 1951 | } |
| 1952 | BUG(); |
| 1953 | } |
| 1954 | |
Tejun Heo | 8c4bfc6 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 1955 | /** |
| 1956 | * pcpu_lpage_first_chunk - remap the first percpu chunk using large page |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1957 | * @ai: pcpu_alloc_info |
Tejun Heo | 8c4bfc6 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 1958 | * @alloc_fn: function to allocate percpu lpage, always called with lpage_size |
| 1959 | * @free_fn: function to free percpu memory, @size <= lpage_size |
| 1960 | * @map_fn: function to map percpu lpage, always called with lpage_size |
| 1961 | * |
Tejun Heo | a530b79 | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 1962 | * This allocator uses large page to build and map the first chunk. |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1963 | * Unlike other helpers, the caller should provide fully initialized |
| 1964 | * @ai. This can be done using pcpu_build_alloc_info(). This two |
| 1965 | * stage initialization is to allow arch code to evaluate the |
Tejun Heo | a530b79 | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 1966 | * parameters before committing to it. |
Tejun Heo | 8c4bfc6 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 1967 | * |
Tejun Heo | a530b79 | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 1968 | * Large pages are allocated as directed by @unit_map and other |
| 1969 | * parameters and mapped to vmalloc space. Unused holes are returned |
| 1970 | * to the page allocator. Note that these holes end up being actively |
| 1971 | * mapped twice - once to the physical mapping and to the vmalloc area |
| 1972 | * for the first percpu chunk. Depending on architecture, this might |
| 1973 | * cause problem when changing page attributes of the returned area. |
| 1974 | * These double mapped areas can be detected using |
| 1975 | * pcpu_lpage_remapped(). |
Tejun Heo | 8c4bfc6 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 1976 | * |
| 1977 | * RETURNS: |
Tejun Heo | fb435d5 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1978 | * 0 on success, -errno on failure. |
Tejun Heo | 8c4bfc6 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 1979 | */ |
Tejun Heo | fb435d5 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1980 | int __init pcpu_lpage_first_chunk(const struct pcpu_alloc_info *ai, |
| 1981 | pcpu_fc_alloc_fn_t alloc_fn, |
| 1982 | pcpu_fc_free_fn_t free_fn, |
| 1983 | pcpu_fc_map_fn_t map_fn) |
Tejun Heo | 8c4bfc6 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 1984 | { |
Tejun Heo | a530b79 | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 1985 | static struct vm_struct vm; |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1986 | const size_t lpage_size = ai->atom_size; |
| 1987 | size_t chunk_size, map_size; |
Tejun Heo | 8c4bfc6 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 1988 | unsigned int cpu; |
Tejun Heo | fb435d5 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1989 | int i, j, unit, nr_units, rc; |
Tejun Heo | 8c4bfc6 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 1990 | |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1991 | nr_units = 0; |
| 1992 | for (i = 0; i < ai->nr_groups; i++) |
| 1993 | nr_units += ai->groups[i].nr_units; |
Tejun Heo | 8c4bfc6 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 1994 | |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1995 | chunk_size = ai->unit_size * nr_units; |
Tejun Heo | a530b79 | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 1996 | BUG_ON(chunk_size % lpage_size); |
| 1997 | |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 1998 | pcpul_size = ai->static_size + ai->reserved_size + ai->dyn_size; |
Tejun Heo | a530b79 | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 1999 | pcpul_lpage_size = lpage_size; |
| 2000 | pcpul_nr_lpages = chunk_size / lpage_size; |
Tejun Heo | 8c4bfc6 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 2001 | |
| 2002 | /* allocate pointer array and alloc large pages */ |
Tejun Heo | a530b79 | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 2003 | map_size = pcpul_nr_lpages * sizeof(pcpul_map[0]); |
Tejun Heo | 8c4bfc6 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 2004 | pcpul_map = alloc_bootmem(map_size); |
| 2005 | |
Tejun Heo | a530b79 | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 2006 | /* allocate all pages */ |
| 2007 | for (i = 0; i < pcpul_nr_lpages; i++) { |
| 2008 | size_t offset = i * lpage_size; |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 2009 | int first_unit = offset / ai->unit_size; |
| 2010 | int last_unit = (offset + lpage_size - 1) / ai->unit_size; |
Tejun Heo | 8c4bfc6 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 2011 | void *ptr; |
| 2012 | |
Tejun Heo | a530b79 | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 2013 | /* find out which cpu is mapped to this unit */ |
| 2014 | for (unit = first_unit; unit <= last_unit; unit++) |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 2015 | if (pcpul_unit_to_cpu(unit, ai, &cpu)) |
Tejun Heo | a530b79 | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 2016 | goto found; |
| 2017 | continue; |
| 2018 | found: |
Tejun Heo | 3cbc856 | 2009-08-14 15:00:50 +0900 | [diff] [blame] | 2019 | ptr = alloc_fn(cpu, lpage_size, lpage_size); |
Tejun Heo | 8c4bfc6 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 2020 | if (!ptr) { |
| 2021 | pr_warning("PERCPU: failed to allocate large page " |
| 2022 | "for cpu%u\n", cpu); |
| 2023 | goto enomem; |
| 2024 | } |
| 2025 | |
Tejun Heo | a530b79 | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 2026 | pcpul_map[i].ptr = ptr; |
Tejun Heo | 8c4bfc6 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 2027 | } |
| 2028 | |
Tejun Heo | a530b79 | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 2029 | /* return unused holes */ |
| 2030 | for (unit = 0; unit < nr_units; unit++) { |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 2031 | size_t start = unit * ai->unit_size; |
| 2032 | size_t end = start + ai->unit_size; |
Tejun Heo | a530b79 | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 2033 | size_t off, next; |
| 2034 | |
| 2035 | /* don't free used part of occupied unit */ |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 2036 | if (pcpul_unit_to_cpu(unit, ai, NULL)) |
Tejun Heo | a530b79 | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 2037 | start += pcpul_size; |
| 2038 | |
| 2039 | /* unit can span more than one page, punch the holes */ |
| 2040 | for (off = start; off < end; off = next) { |
| 2041 | void *ptr = pcpul_map[off / lpage_size].ptr; |
| 2042 | next = min(roundup(off + 1, lpage_size), end); |
| 2043 | if (ptr) |
| 2044 | free_fn(ptr + off % lpage_size, next - off); |
| 2045 | } |
| 2046 | } |
| 2047 | |
| 2048 | /* allocate address, map and copy */ |
| 2049 | vm.flags = VM_ALLOC; |
| 2050 | vm.size = chunk_size; |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 2051 | vm_area_register_early(&vm, ai->unit_size); |
Tejun Heo | a530b79 | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 2052 | |
| 2053 | for (i = 0; i < pcpul_nr_lpages; i++) { |
| 2054 | if (!pcpul_map[i].ptr) |
| 2055 | continue; |
| 2056 | pcpul_map[i].map_addr = vm.addr + i * lpage_size; |
| 2057 | map_fn(pcpul_map[i].ptr, lpage_size, pcpul_map[i].map_addr); |
| 2058 | } |
Tejun Heo | 8c4bfc6 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 2059 | |
| 2060 | for_each_possible_cpu(cpu) |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 2061 | memcpy(vm.addr + pcpul_cpu_to_unit(cpu, ai) * ai->unit_size, |
| 2062 | __per_cpu_load, ai->static_size); |
Tejun Heo | 8c4bfc6 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 2063 | |
| 2064 | /* we're ready, commit */ |
Tejun Heo | 004018e | 2009-08-14 15:00:49 +0900 | [diff] [blame] | 2065 | pr_info("PERCPU: large pages @%p s%zu r%zu d%zu u%zu\n", |
Tejun Heo | fd1e8a1 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 2066 | vm.addr, ai->static_size, ai->reserved_size, ai->dyn_size, |
| 2067 | ai->unit_size); |
Tejun Heo | 8c4bfc6 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 2068 | |
Tejun Heo | fb435d5 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 2069 | rc = pcpu_setup_first_chunk(ai, vm.addr); |
Tejun Heo | 8c4bfc6 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 2070 | |
Tejun Heo | a530b79 | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 2071 | /* |
| 2072 | * Sort pcpul_map array for pcpu_lpage_remapped(). Unmapped |
| 2073 | * lpages are pushed to the end and trimmed. |
| 2074 | */ |
| 2075 | for (i = 0; i < pcpul_nr_lpages - 1; i++) |
| 2076 | for (j = i + 1; j < pcpul_nr_lpages; j++) { |
| 2077 | struct pcpul_ent tmp; |
| 2078 | |
| 2079 | if (!pcpul_map[j].ptr) |
| 2080 | continue; |
| 2081 | if (pcpul_map[i].ptr && |
| 2082 | pcpul_map[i].ptr < pcpul_map[j].ptr) |
| 2083 | continue; |
| 2084 | |
| 2085 | tmp = pcpul_map[i]; |
| 2086 | pcpul_map[i] = pcpul_map[j]; |
| 2087 | pcpul_map[j] = tmp; |
| 2088 | } |
| 2089 | |
| 2090 | while (pcpul_nr_lpages && !pcpul_map[pcpul_nr_lpages - 1].ptr) |
| 2091 | pcpul_nr_lpages--; |
Tejun Heo | 8c4bfc6 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 2092 | |
Tejun Heo | fb435d5 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 2093 | return rc; |
Tejun Heo | 8c4bfc6 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 2094 | |
| 2095 | enomem: |
Tejun Heo | a530b79 | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 2096 | for (i = 0; i < pcpul_nr_lpages; i++) |
| 2097 | if (pcpul_map[i].ptr) |
| 2098 | free_fn(pcpul_map[i].ptr, lpage_size); |
Tejun Heo | 8c4bfc6 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 2099 | free_bootmem(__pa(pcpul_map), map_size); |
| 2100 | return -ENOMEM; |
| 2101 | } |
| 2102 | |
| 2103 | /** |
| 2104 | * pcpu_lpage_remapped - determine whether a kaddr is in pcpul recycled area |
| 2105 | * @kaddr: the kernel address in question |
| 2106 | * |
| 2107 | * Determine whether @kaddr falls in the pcpul recycled area. This is |
| 2108 | * used by pageattr to detect VM aliases and break up the pcpu large |
| 2109 | * page mapping such that the same physical page is not mapped under |
| 2110 | * different attributes. |
| 2111 | * |
| 2112 | * The recycled area is always at the tail of a partially used large |
| 2113 | * page. |
| 2114 | * |
| 2115 | * RETURNS: |
| 2116 | * Address of corresponding remapped pcpu address if match is found; |
| 2117 | * otherwise, NULL. |
| 2118 | */ |
| 2119 | void *pcpu_lpage_remapped(void *kaddr) |
| 2120 | { |
Tejun Heo | a530b79 | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 2121 | unsigned long lpage_mask = pcpul_lpage_size - 1; |
| 2122 | void *lpage_addr = (void *)((unsigned long)kaddr & ~lpage_mask); |
| 2123 | unsigned long offset = (unsigned long)kaddr & lpage_mask; |
| 2124 | int left = 0, right = pcpul_nr_lpages - 1; |
Tejun Heo | 8c4bfc6 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 2125 | int pos; |
| 2126 | |
| 2127 | /* pcpul in use at all? */ |
| 2128 | if (!pcpul_map) |
| 2129 | return NULL; |
| 2130 | |
| 2131 | /* okay, perform binary search */ |
| 2132 | while (left <= right) { |
| 2133 | pos = (left + right) / 2; |
| 2134 | |
| 2135 | if (pcpul_map[pos].ptr < lpage_addr) |
| 2136 | left = pos + 1; |
| 2137 | else if (pcpul_map[pos].ptr > lpage_addr) |
| 2138 | right = pos - 1; |
Tejun Heo | a530b79 | 2009-07-04 08:11:00 +0900 | [diff] [blame] | 2139 | else |
| 2140 | return pcpul_map[pos].map_addr + offset; |
Tejun Heo | 8c4bfc6 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 2141 | } |
| 2142 | |
| 2143 | return NULL; |
| 2144 | } |
Tejun Heo | 08fc458 | 2009-08-14 15:00:49 +0900 | [diff] [blame] | 2145 | #endif /* CONFIG_NEED_PER_CPU_LPAGE_FIRST_CHUNK */ |
Tejun Heo | 8c4bfc6 | 2009-07-04 08:10:59 +0900 | [diff] [blame] | 2146 | |
| 2147 | /* |
Tejun Heo | e74e396 | 2009-03-30 19:07:44 +0900 | [diff] [blame] | 2148 | * Generic percpu area setup. |
| 2149 | * |
| 2150 | * The embedding helper is used because its behavior closely resembles |
| 2151 | * the original non-dynamic generic percpu area setup. This is |
| 2152 | * important because many archs have addressing restrictions and might |
| 2153 | * fail if the percpu area is located far away from the previous |
| 2154 | * location. As an added bonus, in non-NUMA cases, embedding is |
| 2155 | * generally a good idea TLB-wise because percpu area can piggy back |
| 2156 | * on the physical linear memory mapping which uses large page |
| 2157 | * mappings on applicable archs. |
| 2158 | */ |
| 2159 | #ifndef CONFIG_HAVE_SETUP_PER_CPU_AREA |
| 2160 | unsigned long __per_cpu_offset[NR_CPUS] __read_mostly; |
| 2161 | EXPORT_SYMBOL(__per_cpu_offset); |
| 2162 | |
| 2163 | void __init setup_per_cpu_areas(void) |
| 2164 | { |
Tejun Heo | e74e396 | 2009-03-30 19:07:44 +0900 | [diff] [blame] | 2165 | unsigned long delta; |
| 2166 | unsigned int cpu; |
Tejun Heo | fb435d5 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 2167 | int rc; |
Tejun Heo | e74e396 | 2009-03-30 19:07:44 +0900 | [diff] [blame] | 2168 | |
| 2169 | /* |
| 2170 | * Always reserve area for module percpu variables. That's |
| 2171 | * what the legacy allocator did. |
| 2172 | */ |
Tejun Heo | fb435d5 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 2173 | rc = pcpu_embed_first_chunk(PERCPU_MODULE_RESERVE, |
| 2174 | PERCPU_DYNAMIC_RESERVE); |
| 2175 | if (rc < 0) |
Tejun Heo | e74e396 | 2009-03-30 19:07:44 +0900 | [diff] [blame] | 2176 | panic("Failed to initialized percpu areas."); |
| 2177 | |
| 2178 | delta = (unsigned long)pcpu_base_addr - (unsigned long)__per_cpu_start; |
| 2179 | for_each_possible_cpu(cpu) |
Tejun Heo | fb435d5 | 2009-08-14 15:00:51 +0900 | [diff] [blame] | 2180 | __per_cpu_offset[cpu] = delta + pcpu_unit_offsets[cpu]; |
Tejun Heo | e74e396 | 2009-03-30 19:07:44 +0900 | [diff] [blame] | 2181 | } |
| 2182 | #endif /* CONFIG_HAVE_SETUP_PER_CPU_AREA */ |