Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1 | /* |
| 2 | * zcache.c |
| 3 | * |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 4 | * Copyright (c) 2010-2012, Dan Magenheimer, Oracle Corp. |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 5 | * Copyright (c) 2010,2011, Nitin Gupta |
| 6 | * |
| 7 | * Zcache provides an in-kernel "host implementation" for transcendent memory |
| 8 | * and, thus indirectly, for cleancache and frontswap. Zcache includes two |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 9 | * page-accessible memory [1] interfaces, both utilizing lzo1x compression: |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 10 | * 1) "compression buddies" ("zbud") is used for ephemeral pages |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 11 | * 2) xvmalloc is used for persistent pages. |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 12 | * Xvmalloc (based on the TLSF allocator) has very low fragmentation |
| 13 | * so maximizes space efficiency, while zbud allows pairs (and potentially, |
| 14 | * in the future, more than a pair of) compressed pages to be closely linked |
| 15 | * so that reclaiming can be done via the kernel's physical-page-oriented |
| 16 | * "shrinker" interface. |
| 17 | * |
| 18 | * [1] For a definition of page-accessible memory (aka PAM), see: |
| 19 | * http://marc.info/?l=linux-mm&m=127811271605009 |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 20 | * RAMSTER TODO: |
| 21 | * - handle remotifying of buddied pages (see zbud_remotify_zbpg) |
| 22 | * - kernel boot params: nocleancache/nofrontswap don't always work?!? |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 23 | */ |
| 24 | |
| 25 | #include <linux/module.h> |
| 26 | #include <linux/cpu.h> |
| 27 | #include <linux/highmem.h> |
| 28 | #include <linux/list.h> |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 29 | #include <linux/lzo.h> |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 30 | #include <linux/slab.h> |
| 31 | #include <linux/spinlock.h> |
| 32 | #include <linux/types.h> |
| 33 | #include <linux/atomic.h> |
| 34 | #include <linux/math64.h> |
| 35 | #include "tmem.h" |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 36 | #include "zcache.h" |
| 37 | #include "ramster.h" |
| 38 | #include "cluster/tcp.h" |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 39 | |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 40 | #include "xvmalloc.h" /* temporary until change to zsmalloc */ |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 41 | |
| 42 | #define RAMSTER_TESTING |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 43 | |
| 44 | #if (!defined(CONFIG_CLEANCACHE) && !defined(CONFIG_FRONTSWAP)) |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 45 | #error "ramster is useless without CONFIG_CLEANCACHE or CONFIG_FRONTSWAP" |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 46 | #endif |
| 47 | #ifdef CONFIG_CLEANCACHE |
| 48 | #include <linux/cleancache.h> |
| 49 | #endif |
| 50 | #ifdef CONFIG_FRONTSWAP |
| 51 | #include <linux/frontswap.h> |
| 52 | #endif |
| 53 | |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 54 | enum ramster_remotify_op { |
| 55 | RAMSTER_REMOTIFY_EPH_PUT, |
| 56 | RAMSTER_REMOTIFY_PERS_PUT, |
| 57 | RAMSTER_REMOTIFY_FLUSH_PAGE, |
| 58 | RAMSTER_REMOTIFY_FLUSH_OBJ, |
| 59 | RAMSTER_INTRANSIT_PERS |
| 60 | }; |
| 61 | |
| 62 | struct ramster_remotify_hdr { |
| 63 | enum ramster_remotify_op op; |
| 64 | struct list_head list; |
| 65 | }; |
| 66 | |
| 67 | #define ZBH_SENTINEL 0x43214321 |
| 68 | #define ZBPG_SENTINEL 0xdeadbeef |
| 69 | |
| 70 | #define ZBUD_MAX_BUDS 2 |
| 71 | |
| 72 | struct zbud_hdr { |
| 73 | struct ramster_remotify_hdr rem_op; |
| 74 | uint16_t client_id; |
| 75 | uint16_t pool_id; |
| 76 | struct tmem_oid oid; |
| 77 | uint32_t index; |
| 78 | uint16_t size; /* compressed size in bytes, zero means unused */ |
| 79 | DECL_SENTINEL |
| 80 | }; |
| 81 | |
| 82 | #define ZVH_SENTINEL 0x43214321 |
| 83 | static const int zv_max_page_size = (PAGE_SIZE / 8) * 7; |
| 84 | |
| 85 | struct zv_hdr { |
| 86 | struct ramster_remotify_hdr rem_op; |
| 87 | uint16_t client_id; |
| 88 | uint16_t pool_id; |
| 89 | struct tmem_oid oid; |
| 90 | uint32_t index; |
| 91 | DECL_SENTINEL |
| 92 | }; |
| 93 | |
| 94 | struct flushlist_node { |
| 95 | struct ramster_remotify_hdr rem_op; |
| 96 | struct tmem_xhandle xh; |
| 97 | }; |
| 98 | |
| 99 | union { |
| 100 | struct ramster_remotify_hdr rem_op; |
| 101 | struct zv_hdr zv; |
| 102 | struct zbud_hdr zbud; |
| 103 | struct flushlist_node flist; |
| 104 | } remotify_list_node; |
| 105 | |
| 106 | static LIST_HEAD(zcache_rem_op_list); |
| 107 | static DEFINE_SPINLOCK(zcache_rem_op_list_lock); |
| 108 | |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 109 | #if 0 |
| 110 | /* this is more aggressive but may cause other problems? */ |
| 111 | #define ZCACHE_GFP_MASK (GFP_ATOMIC | __GFP_NORETRY | __GFP_NOWARN) |
| 112 | #else |
| 113 | #define ZCACHE_GFP_MASK \ |
| 114 | (__GFP_FS | __GFP_NORETRY | __GFP_NOWARN | __GFP_NOMEMALLOC) |
| 115 | #endif |
| 116 | |
| 117 | #define MAX_POOLS_PER_CLIENT 16 |
| 118 | |
| 119 | #define MAX_CLIENTS 16 |
| 120 | #define LOCAL_CLIENT ((uint16_t)-1) |
| 121 | |
| 122 | MODULE_LICENSE("GPL"); |
| 123 | |
| 124 | struct zcache_client { |
| 125 | struct tmem_pool *tmem_pools[MAX_POOLS_PER_CLIENT]; |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 126 | struct xv_pool *xvpool; |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 127 | bool allocated; |
| 128 | atomic_t refcount; |
| 129 | }; |
| 130 | |
| 131 | static struct zcache_client zcache_host; |
| 132 | static struct zcache_client zcache_clients[MAX_CLIENTS]; |
| 133 | |
| 134 | static inline uint16_t get_client_id_from_client(struct zcache_client *cli) |
| 135 | { |
| 136 | BUG_ON(cli == NULL); |
| 137 | if (cli == &zcache_host) |
| 138 | return LOCAL_CLIENT; |
| 139 | return cli - &zcache_clients[0]; |
| 140 | } |
| 141 | |
| 142 | static inline bool is_local_client(struct zcache_client *cli) |
| 143 | { |
| 144 | return cli == &zcache_host; |
| 145 | } |
| 146 | |
| 147 | /********** |
| 148 | * Compression buddies ("zbud") provides for packing two (or, possibly |
| 149 | * in the future, more) compressed ephemeral pages into a single "raw" |
| 150 | * (physical) page and tracking them with data structures so that |
| 151 | * the raw pages can be easily reclaimed. |
| 152 | * |
| 153 | * A zbud page ("zbpg") is an aligned page containing a list_head, |
| 154 | * a lock, and two "zbud headers". The remainder of the physical |
| 155 | * page is divided up into aligned 64-byte "chunks" which contain |
| 156 | * the compressed data for zero, one, or two zbuds. Each zbpg |
| 157 | * resides on: (1) an "unused list" if it has no zbuds; (2) a |
| 158 | * "buddied" list if it is fully populated with two zbuds; or |
| 159 | * (3) one of PAGE_SIZE/64 "unbuddied" lists indexed by how many chunks |
| 160 | * the one unbuddied zbud uses. The data inside a zbpg cannot be |
| 161 | * read or written unless the zbpg's lock is held. |
| 162 | */ |
| 163 | |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 164 | struct zbud_page { |
| 165 | struct list_head bud_list; |
| 166 | spinlock_t lock; |
| 167 | struct zbud_hdr buddy[ZBUD_MAX_BUDS]; |
| 168 | DECL_SENTINEL |
| 169 | /* followed by NUM_CHUNK aligned CHUNK_SIZE-byte chunks */ |
| 170 | }; |
| 171 | |
| 172 | #define CHUNK_SHIFT 6 |
| 173 | #define CHUNK_SIZE (1 << CHUNK_SHIFT) |
| 174 | #define CHUNK_MASK (~(CHUNK_SIZE-1)) |
| 175 | #define NCHUNKS (((PAGE_SIZE - sizeof(struct zbud_page)) & \ |
| 176 | CHUNK_MASK) >> CHUNK_SHIFT) |
| 177 | #define MAX_CHUNK (NCHUNKS-1) |
| 178 | |
| 179 | static struct { |
| 180 | struct list_head list; |
| 181 | unsigned count; |
| 182 | } zbud_unbuddied[NCHUNKS]; |
| 183 | /* list N contains pages with N chunks USED and NCHUNKS-N unused */ |
| 184 | /* element 0 is never used but optimizing that isn't worth it */ |
| 185 | static unsigned long zbud_cumul_chunk_counts[NCHUNKS]; |
| 186 | |
| 187 | struct list_head zbud_buddied_list; |
| 188 | static unsigned long zcache_zbud_buddied_count; |
| 189 | |
| 190 | /* protects the buddied list and all unbuddied lists */ |
| 191 | static DEFINE_SPINLOCK(zbud_budlists_spinlock); |
| 192 | |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 193 | static atomic_t zcache_zbud_curr_raw_pages; |
| 194 | static atomic_t zcache_zbud_curr_zpages; |
| 195 | static unsigned long zcache_zbud_curr_zbytes; |
| 196 | static unsigned long zcache_zbud_cumul_zpages; |
| 197 | static unsigned long zcache_zbud_cumul_zbytes; |
| 198 | static unsigned long zcache_compress_poor; |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 199 | static unsigned long zcache_policy_percent_exceeded; |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 200 | static unsigned long zcache_mean_compress_poor; |
| 201 | |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 202 | /* |
| 203 | * RAMster counters |
| 204 | * - Remote pages are pages with a local pampd but the data is remote |
| 205 | * - Foreign pages are pages stored locally but belonging to another node |
| 206 | */ |
| 207 | static atomic_t ramster_remote_pers_pages = ATOMIC_INIT(0); |
| 208 | static unsigned long ramster_pers_remotify_enable; |
| 209 | static unsigned long ramster_eph_remotify_enable; |
| 210 | static unsigned long ramster_eph_pages_remoted; |
| 211 | static unsigned long ramster_eph_pages_remote_failed; |
| 212 | static unsigned long ramster_pers_pages_remoted; |
| 213 | static unsigned long ramster_pers_pages_remote_failed; |
| 214 | static unsigned long ramster_pers_pages_remote_nomem; |
| 215 | static unsigned long ramster_remote_objects_flushed; |
| 216 | static unsigned long ramster_remote_object_flushes_failed; |
| 217 | static unsigned long ramster_remote_pages_flushed; |
| 218 | static unsigned long ramster_remote_page_flushes_failed; |
| 219 | static unsigned long ramster_remote_eph_pages_succ_get; |
| 220 | static unsigned long ramster_remote_pers_pages_succ_get; |
| 221 | static unsigned long ramster_remote_eph_pages_unsucc_get; |
| 222 | static unsigned long ramster_remote_pers_pages_unsucc_get; |
| 223 | static atomic_t ramster_curr_flnode_count = ATOMIC_INIT(0); |
| 224 | static unsigned long ramster_curr_flnode_count_max; |
| 225 | static atomic_t ramster_foreign_eph_pampd_count = ATOMIC_INIT(0); |
| 226 | static unsigned long ramster_foreign_eph_pampd_count_max; |
| 227 | static atomic_t ramster_foreign_pers_pampd_count = ATOMIC_INIT(0); |
| 228 | static unsigned long ramster_foreign_pers_pampd_count_max; |
| 229 | |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 230 | /* forward references */ |
| 231 | static void *zcache_get_free_page(void); |
| 232 | static void zcache_free_page(void *p); |
| 233 | |
| 234 | /* |
| 235 | * zbud helper functions |
| 236 | */ |
| 237 | |
| 238 | static inline unsigned zbud_max_buddy_size(void) |
| 239 | { |
| 240 | return MAX_CHUNK << CHUNK_SHIFT; |
| 241 | } |
| 242 | |
| 243 | static inline unsigned zbud_size_to_chunks(unsigned size) |
| 244 | { |
| 245 | BUG_ON(size == 0 || size > zbud_max_buddy_size()); |
| 246 | return (size + CHUNK_SIZE - 1) >> CHUNK_SHIFT; |
| 247 | } |
| 248 | |
| 249 | static inline int zbud_budnum(struct zbud_hdr *zh) |
| 250 | { |
| 251 | unsigned offset = (unsigned long)zh & (PAGE_SIZE - 1); |
| 252 | struct zbud_page *zbpg = NULL; |
| 253 | unsigned budnum = -1U; |
| 254 | int i; |
| 255 | |
| 256 | for (i = 0; i < ZBUD_MAX_BUDS; i++) |
| 257 | if (offset == offsetof(typeof(*zbpg), buddy[i])) { |
| 258 | budnum = i; |
| 259 | break; |
| 260 | } |
| 261 | BUG_ON(budnum == -1U); |
| 262 | return budnum; |
| 263 | } |
| 264 | |
| 265 | static char *zbud_data(struct zbud_hdr *zh, unsigned size) |
| 266 | { |
| 267 | struct zbud_page *zbpg; |
| 268 | char *p; |
| 269 | unsigned budnum; |
| 270 | |
| 271 | ASSERT_SENTINEL(zh, ZBH); |
| 272 | budnum = zbud_budnum(zh); |
| 273 | BUG_ON(size == 0 || size > zbud_max_buddy_size()); |
| 274 | zbpg = container_of(zh, struct zbud_page, buddy[budnum]); |
| 275 | ASSERT_SPINLOCK(&zbpg->lock); |
| 276 | p = (char *)zbpg; |
| 277 | if (budnum == 0) |
| 278 | p += ((sizeof(struct zbud_page) + CHUNK_SIZE - 1) & |
| 279 | CHUNK_MASK); |
| 280 | else if (budnum == 1) |
| 281 | p += PAGE_SIZE - ((size + CHUNK_SIZE - 1) & CHUNK_MASK); |
| 282 | return p; |
| 283 | } |
| 284 | |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 285 | static void zbud_copy_from_pampd(char *data, size_t *size, struct zbud_hdr *zh) |
| 286 | { |
| 287 | struct zbud_page *zbpg; |
| 288 | char *p; |
| 289 | unsigned budnum; |
| 290 | |
| 291 | ASSERT_SENTINEL(zh, ZBH); |
| 292 | budnum = zbud_budnum(zh); |
| 293 | zbpg = container_of(zh, struct zbud_page, buddy[budnum]); |
| 294 | spin_lock(&zbpg->lock); |
| 295 | BUG_ON(zh->size > *size); |
| 296 | p = (char *)zbpg; |
| 297 | if (budnum == 0) |
| 298 | p += ((sizeof(struct zbud_page) + CHUNK_SIZE - 1) & |
| 299 | CHUNK_MASK); |
| 300 | else if (budnum == 1) |
| 301 | p += PAGE_SIZE - ((zh->size + CHUNK_SIZE - 1) & CHUNK_MASK); |
| 302 | /* client should be filled in by caller */ |
| 303 | memcpy(data, p, zh->size); |
| 304 | *size = zh->size; |
| 305 | spin_unlock(&zbpg->lock); |
| 306 | } |
| 307 | |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 308 | /* |
| 309 | * zbud raw page management |
| 310 | */ |
| 311 | |
| 312 | static struct zbud_page *zbud_alloc_raw_page(void) |
| 313 | { |
| 314 | struct zbud_page *zbpg = NULL; |
| 315 | struct zbud_hdr *zh0, *zh1; |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 316 | zbpg = zcache_get_free_page(); |
| 317 | if (likely(zbpg != NULL)) { |
| 318 | INIT_LIST_HEAD(&zbpg->bud_list); |
| 319 | zh0 = &zbpg->buddy[0]; zh1 = &zbpg->buddy[1]; |
| 320 | spin_lock_init(&zbpg->lock); |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 321 | atomic_inc(&zcache_zbud_curr_raw_pages); |
| 322 | INIT_LIST_HEAD(&zbpg->bud_list); |
| 323 | SET_SENTINEL(zbpg, ZBPG); |
| 324 | zh0->size = 0; zh1->size = 0; |
| 325 | tmem_oid_set_invalid(&zh0->oid); |
| 326 | tmem_oid_set_invalid(&zh1->oid); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 327 | } |
| 328 | return zbpg; |
| 329 | } |
| 330 | |
| 331 | static void zbud_free_raw_page(struct zbud_page *zbpg) |
| 332 | { |
| 333 | struct zbud_hdr *zh0 = &zbpg->buddy[0], *zh1 = &zbpg->buddy[1]; |
| 334 | |
| 335 | ASSERT_SENTINEL(zbpg, ZBPG); |
| 336 | BUG_ON(!list_empty(&zbpg->bud_list)); |
| 337 | ASSERT_SPINLOCK(&zbpg->lock); |
| 338 | BUG_ON(zh0->size != 0 || tmem_oid_valid(&zh0->oid)); |
| 339 | BUG_ON(zh1->size != 0 || tmem_oid_valid(&zh1->oid)); |
| 340 | INVERT_SENTINEL(zbpg, ZBPG); |
| 341 | spin_unlock(&zbpg->lock); |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 342 | atomic_dec(&zcache_zbud_curr_raw_pages); |
| 343 | zcache_free_page(zbpg); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 344 | } |
| 345 | |
| 346 | /* |
| 347 | * core zbud handling routines |
| 348 | */ |
| 349 | |
| 350 | static unsigned zbud_free(struct zbud_hdr *zh) |
| 351 | { |
| 352 | unsigned size; |
| 353 | |
| 354 | ASSERT_SENTINEL(zh, ZBH); |
| 355 | BUG_ON(!tmem_oid_valid(&zh->oid)); |
| 356 | size = zh->size; |
| 357 | BUG_ON(zh->size == 0 || zh->size > zbud_max_buddy_size()); |
| 358 | zh->size = 0; |
| 359 | tmem_oid_set_invalid(&zh->oid); |
| 360 | INVERT_SENTINEL(zh, ZBH); |
| 361 | zcache_zbud_curr_zbytes -= size; |
| 362 | atomic_dec(&zcache_zbud_curr_zpages); |
| 363 | return size; |
| 364 | } |
| 365 | |
| 366 | static void zbud_free_and_delist(struct zbud_hdr *zh) |
| 367 | { |
| 368 | unsigned chunks; |
| 369 | struct zbud_hdr *zh_other; |
| 370 | unsigned budnum = zbud_budnum(zh), size; |
| 371 | struct zbud_page *zbpg = |
| 372 | container_of(zh, struct zbud_page, buddy[budnum]); |
| 373 | |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 374 | /* FIXME, should be BUG_ON, pool destruction path doesn't disable |
| 375 | * interrupts tmem_destroy_pool()->tmem_pampd_destroy_all_in_obj()-> |
| 376 | * tmem_objnode_node_destroy()-> zcache_pampd_free() */ |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 377 | WARN_ON(!irqs_disabled()); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 378 | spin_lock(&zbpg->lock); |
| 379 | if (list_empty(&zbpg->bud_list)) { |
| 380 | /* ignore zombie page... see zbud_evict_pages() */ |
| 381 | spin_unlock(&zbpg->lock); |
| 382 | return; |
| 383 | } |
| 384 | size = zbud_free(zh); |
| 385 | ASSERT_SPINLOCK(&zbpg->lock); |
| 386 | zh_other = &zbpg->buddy[(budnum == 0) ? 1 : 0]; |
| 387 | if (zh_other->size == 0) { /* was unbuddied: unlist and free */ |
| 388 | chunks = zbud_size_to_chunks(size) ; |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 389 | spin_lock(&zbud_budlists_spinlock); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 390 | BUG_ON(list_empty(&zbud_unbuddied[chunks].list)); |
| 391 | list_del_init(&zbpg->bud_list); |
| 392 | zbud_unbuddied[chunks].count--; |
| 393 | spin_unlock(&zbud_budlists_spinlock); |
| 394 | zbud_free_raw_page(zbpg); |
| 395 | } else { /* was buddied: move remaining buddy to unbuddied list */ |
| 396 | chunks = zbud_size_to_chunks(zh_other->size) ; |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 397 | spin_lock(&zbud_budlists_spinlock); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 398 | list_del_init(&zbpg->bud_list); |
| 399 | zcache_zbud_buddied_count--; |
| 400 | list_add_tail(&zbpg->bud_list, &zbud_unbuddied[chunks].list); |
| 401 | zbud_unbuddied[chunks].count++; |
Dan Magenheimer | 49b81a3 | 2012-05-10 12:06:21 -0700 | [diff] [blame] | 402 | spin_unlock(&zbud_budlists_spinlock); |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 403 | spin_unlock(&zbpg->lock); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 404 | } |
| 405 | } |
| 406 | |
| 407 | static struct zbud_hdr *zbud_create(uint16_t client_id, uint16_t pool_id, |
| 408 | struct tmem_oid *oid, |
| 409 | uint32_t index, struct page *page, |
| 410 | void *cdata, unsigned size) |
| 411 | { |
| 412 | struct zbud_hdr *zh0, *zh1, *zh = NULL; |
| 413 | struct zbud_page *zbpg = NULL, *ztmp; |
| 414 | unsigned nchunks; |
| 415 | char *to; |
| 416 | int i, found_good_buddy = 0; |
| 417 | |
| 418 | nchunks = zbud_size_to_chunks(size) ; |
| 419 | for (i = MAX_CHUNK - nchunks + 1; i > 0; i--) { |
| 420 | spin_lock(&zbud_budlists_spinlock); |
| 421 | if (!list_empty(&zbud_unbuddied[i].list)) { |
| 422 | list_for_each_entry_safe(zbpg, ztmp, |
| 423 | &zbud_unbuddied[i].list, bud_list) { |
| 424 | if (spin_trylock(&zbpg->lock)) { |
| 425 | found_good_buddy = i; |
| 426 | goto found_unbuddied; |
| 427 | } |
| 428 | } |
| 429 | } |
| 430 | spin_unlock(&zbud_budlists_spinlock); |
| 431 | } |
| 432 | /* didn't find a good buddy, try allocating a new page */ |
| 433 | zbpg = zbud_alloc_raw_page(); |
| 434 | if (unlikely(zbpg == NULL)) |
| 435 | goto out; |
| 436 | /* ok, have a page, now compress the data before taking locks */ |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 437 | spin_lock(&zbud_budlists_spinlock); |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 438 | spin_lock(&zbpg->lock); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 439 | list_add_tail(&zbpg->bud_list, &zbud_unbuddied[nchunks].list); |
| 440 | zbud_unbuddied[nchunks].count++; |
| 441 | zh = &zbpg->buddy[0]; |
| 442 | goto init_zh; |
| 443 | |
| 444 | found_unbuddied: |
| 445 | ASSERT_SPINLOCK(&zbpg->lock); |
| 446 | zh0 = &zbpg->buddy[0]; zh1 = &zbpg->buddy[1]; |
| 447 | BUG_ON(!((zh0->size == 0) ^ (zh1->size == 0))); |
| 448 | if (zh0->size != 0) { /* buddy0 in use, buddy1 is vacant */ |
| 449 | ASSERT_SENTINEL(zh0, ZBH); |
| 450 | zh = zh1; |
| 451 | } else if (zh1->size != 0) { /* buddy1 in use, buddy0 is vacant */ |
| 452 | ASSERT_SENTINEL(zh1, ZBH); |
| 453 | zh = zh0; |
| 454 | } else |
| 455 | BUG(); |
| 456 | list_del_init(&zbpg->bud_list); |
| 457 | zbud_unbuddied[found_good_buddy].count--; |
| 458 | list_add_tail(&zbpg->bud_list, &zbud_buddied_list); |
| 459 | zcache_zbud_buddied_count++; |
| 460 | |
| 461 | init_zh: |
| 462 | SET_SENTINEL(zh, ZBH); |
| 463 | zh->size = size; |
| 464 | zh->index = index; |
| 465 | zh->oid = *oid; |
| 466 | zh->pool_id = pool_id; |
| 467 | zh->client_id = client_id; |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 468 | to = zbud_data(zh, size); |
| 469 | memcpy(to, cdata, size); |
| 470 | spin_unlock(&zbpg->lock); |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 471 | spin_unlock(&zbud_budlists_spinlock); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 472 | zbud_cumul_chunk_counts[nchunks]++; |
| 473 | atomic_inc(&zcache_zbud_curr_zpages); |
| 474 | zcache_zbud_cumul_zpages++; |
| 475 | zcache_zbud_curr_zbytes += size; |
| 476 | zcache_zbud_cumul_zbytes += size; |
| 477 | out: |
| 478 | return zh; |
| 479 | } |
| 480 | |
| 481 | static int zbud_decompress(struct page *page, struct zbud_hdr *zh) |
| 482 | { |
| 483 | struct zbud_page *zbpg; |
| 484 | unsigned budnum = zbud_budnum(zh); |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 485 | size_t out_len = PAGE_SIZE; |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 486 | char *to_va, *from_va; |
| 487 | unsigned size; |
| 488 | int ret = 0; |
| 489 | |
| 490 | zbpg = container_of(zh, struct zbud_page, buddy[budnum]); |
| 491 | spin_lock(&zbpg->lock); |
| 492 | if (list_empty(&zbpg->bud_list)) { |
| 493 | /* ignore zombie page... see zbud_evict_pages() */ |
| 494 | ret = -EINVAL; |
| 495 | goto out; |
| 496 | } |
| 497 | ASSERT_SENTINEL(zh, ZBH); |
| 498 | BUG_ON(zh->size == 0 || zh->size > zbud_max_buddy_size()); |
Linus Torvalds | 9f39383 | 2012-03-21 09:40:26 -0700 | [diff] [blame] | 499 | to_va = kmap_atomic(page); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 500 | size = zh->size; |
| 501 | from_va = zbud_data(zh, size); |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 502 | ret = lzo1x_decompress_safe(from_va, size, to_va, &out_len); |
| 503 | BUG_ON(ret != LZO_E_OK); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 504 | BUG_ON(out_len != PAGE_SIZE); |
Linus Torvalds | 9f39383 | 2012-03-21 09:40:26 -0700 | [diff] [blame] | 505 | kunmap_atomic(to_va); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 506 | out: |
| 507 | spin_unlock(&zbpg->lock); |
| 508 | return ret; |
| 509 | } |
| 510 | |
| 511 | /* |
| 512 | * The following routines handle shrinking of ephemeral pages by evicting |
| 513 | * pages "least valuable" first. |
| 514 | */ |
| 515 | |
| 516 | static unsigned long zcache_evicted_raw_pages; |
| 517 | static unsigned long zcache_evicted_buddied_pages; |
| 518 | static unsigned long zcache_evicted_unbuddied_pages; |
| 519 | |
| 520 | static struct tmem_pool *zcache_get_pool_by_id(uint16_t cli_id, |
| 521 | uint16_t poolid); |
| 522 | static void zcache_put_pool(struct tmem_pool *pool); |
| 523 | |
| 524 | /* |
| 525 | * Flush and free all zbuds in a zbpg, then free the pageframe |
| 526 | */ |
| 527 | static void zbud_evict_zbpg(struct zbud_page *zbpg) |
| 528 | { |
| 529 | struct zbud_hdr *zh; |
| 530 | int i, j; |
| 531 | uint32_t pool_id[ZBUD_MAX_BUDS], client_id[ZBUD_MAX_BUDS]; |
| 532 | uint32_t index[ZBUD_MAX_BUDS]; |
| 533 | struct tmem_oid oid[ZBUD_MAX_BUDS]; |
| 534 | struct tmem_pool *pool; |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 535 | unsigned long flags; |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 536 | |
| 537 | ASSERT_SPINLOCK(&zbpg->lock); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 538 | for (i = 0, j = 0; i < ZBUD_MAX_BUDS; i++) { |
| 539 | zh = &zbpg->buddy[i]; |
| 540 | if (zh->size) { |
| 541 | client_id[j] = zh->client_id; |
| 542 | pool_id[j] = zh->pool_id; |
| 543 | oid[j] = zh->oid; |
| 544 | index[j] = zh->index; |
| 545 | j++; |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 546 | } |
| 547 | } |
| 548 | spin_unlock(&zbpg->lock); |
| 549 | for (i = 0; i < j; i++) { |
| 550 | pool = zcache_get_pool_by_id(client_id[i], pool_id[i]); |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 551 | BUG_ON(pool == NULL); |
| 552 | local_irq_save(flags); |
| 553 | /* these flushes should dispose of any local storage */ |
| 554 | tmem_flush_page(pool, &oid[i], index[i]); |
| 555 | local_irq_restore(flags); |
| 556 | zcache_put_pool(pool); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 557 | } |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 558 | } |
| 559 | |
| 560 | /* |
| 561 | * Free nr pages. This code is funky because we want to hold the locks |
| 562 | * protecting various lists for as short a time as possible, and in some |
| 563 | * circumstances the list may change asynchronously when the list lock is |
| 564 | * not held. In some cases we also trylock not only to avoid waiting on a |
| 565 | * page in use by another cpu, but also to avoid potential deadlock due to |
| 566 | * lock inversion. |
| 567 | */ |
| 568 | static void zbud_evict_pages(int nr) |
| 569 | { |
| 570 | struct zbud_page *zbpg; |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 571 | int i, newly_unused_pages = 0; |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 572 | |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 573 | |
| 574 | /* now try freeing unbuddied pages, starting with least space avail */ |
| 575 | for (i = 0; i < MAX_CHUNK; i++) { |
| 576 | retry_unbud_list_i: |
| 577 | spin_lock_bh(&zbud_budlists_spinlock); |
| 578 | if (list_empty(&zbud_unbuddied[i].list)) { |
| 579 | spin_unlock_bh(&zbud_budlists_spinlock); |
| 580 | continue; |
| 581 | } |
| 582 | list_for_each_entry(zbpg, &zbud_unbuddied[i].list, bud_list) { |
| 583 | if (unlikely(!spin_trylock(&zbpg->lock))) |
| 584 | continue; |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 585 | zbud_unbuddied[i].count--; |
| 586 | spin_unlock(&zbud_budlists_spinlock); |
| 587 | zcache_evicted_unbuddied_pages++; |
| 588 | /* want budlists unlocked when doing zbpg eviction */ |
| 589 | zbud_evict_zbpg(zbpg); |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 590 | newly_unused_pages++; |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 591 | local_bh_enable(); |
| 592 | if (--nr <= 0) |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 593 | goto evict_unused; |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 594 | goto retry_unbud_list_i; |
| 595 | } |
| 596 | spin_unlock_bh(&zbud_budlists_spinlock); |
| 597 | } |
| 598 | |
| 599 | /* as a last resort, free buddied pages */ |
| 600 | retry_bud_list: |
| 601 | spin_lock_bh(&zbud_budlists_spinlock); |
| 602 | if (list_empty(&zbud_buddied_list)) { |
| 603 | spin_unlock_bh(&zbud_budlists_spinlock); |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 604 | goto evict_unused; |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 605 | } |
| 606 | list_for_each_entry(zbpg, &zbud_buddied_list, bud_list) { |
| 607 | if (unlikely(!spin_trylock(&zbpg->lock))) |
| 608 | continue; |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 609 | zcache_zbud_buddied_count--; |
| 610 | spin_unlock(&zbud_budlists_spinlock); |
| 611 | zcache_evicted_buddied_pages++; |
| 612 | /* want budlists unlocked when doing zbpg eviction */ |
| 613 | zbud_evict_zbpg(zbpg); |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 614 | newly_unused_pages++; |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 615 | local_bh_enable(); |
| 616 | if (--nr <= 0) |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 617 | goto evict_unused; |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 618 | goto retry_bud_list; |
| 619 | } |
| 620 | spin_unlock_bh(&zbud_budlists_spinlock); |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 621 | |
| 622 | evict_unused: |
| 623 | return; |
| 624 | } |
| 625 | |
| 626 | static DEFINE_PER_CPU(unsigned char *, zcache_remoteputmem); |
| 627 | |
| 628 | static int zbud_remotify_zbud(struct tmem_xhandle *xh, char *data, |
| 629 | size_t size) |
| 630 | { |
| 631 | struct tmem_pool *pool; |
| 632 | int i, remotenode, ret = -1; |
| 633 | unsigned char cksum, *p; |
| 634 | unsigned long flags; |
| 635 | |
| 636 | for (p = data, cksum = 0, i = 0; i < size; i++) |
| 637 | cksum += *p; |
| 638 | ret = ramster_remote_put(xh, data, size, true, &remotenode); |
| 639 | if (ret == 0) { |
| 640 | /* data was successfully remoted so change the local version |
| 641 | * to point to the remote node where it landed */ |
| 642 | pool = zcache_get_pool_by_id(LOCAL_CLIENT, xh->pool_id); |
| 643 | BUG_ON(pool == NULL); |
| 644 | local_irq_save(flags); |
| 645 | /* tmem_replace will also free up any local space */ |
| 646 | (void)tmem_replace(pool, &xh->oid, xh->index, |
| 647 | pampd_make_remote(remotenode, size, cksum)); |
| 648 | local_irq_restore(flags); |
| 649 | zcache_put_pool(pool); |
| 650 | ramster_eph_pages_remoted++; |
| 651 | ret = 0; |
| 652 | } else |
| 653 | ramster_eph_pages_remote_failed++; |
| 654 | return ret; |
| 655 | } |
| 656 | |
| 657 | static int zbud_remotify_zbpg(struct zbud_page *zbpg) |
| 658 | { |
| 659 | struct zbud_hdr *zh1, *zh2 = NULL; |
| 660 | struct tmem_xhandle xh1, xh2 = { 0 }; |
| 661 | char *data1 = NULL, *data2 = NULL; |
| 662 | size_t size1 = 0, size2 = 0; |
| 663 | int ret = 0; |
| 664 | unsigned char *tmpmem = __get_cpu_var(zcache_remoteputmem); |
| 665 | |
| 666 | ASSERT_SPINLOCK(&zbpg->lock); |
| 667 | if (zbpg->buddy[0].size == 0) |
| 668 | zh1 = &zbpg->buddy[1]; |
| 669 | else if (zbpg->buddy[1].size == 0) |
| 670 | zh1 = &zbpg->buddy[0]; |
| 671 | else { |
| 672 | zh1 = &zbpg->buddy[0]; |
| 673 | zh2 = &zbpg->buddy[1]; |
| 674 | } |
| 675 | /* don't remotify pages that are already remotified */ |
| 676 | if (zh1->client_id != LOCAL_CLIENT) |
| 677 | zh1 = NULL; |
| 678 | if ((zh2 != NULL) && (zh2->client_id != LOCAL_CLIENT)) |
| 679 | zh2 = NULL; |
| 680 | |
| 681 | /* copy the data and metadata so can release lock */ |
| 682 | if (zh1 != NULL) { |
| 683 | xh1.client_id = zh1->client_id; |
| 684 | xh1.pool_id = zh1->pool_id; |
| 685 | xh1.oid = zh1->oid; |
| 686 | xh1.index = zh1->index; |
| 687 | size1 = zh1->size; |
| 688 | data1 = zbud_data(zh1, size1); |
| 689 | memcpy(tmpmem, zbud_data(zh1, size1), size1); |
| 690 | data1 = tmpmem; |
| 691 | tmpmem += size1; |
| 692 | } |
| 693 | if (zh2 != NULL) { |
| 694 | xh2.client_id = zh2->client_id; |
| 695 | xh2.pool_id = zh2->pool_id; |
| 696 | xh2.oid = zh2->oid; |
| 697 | xh2.index = zh2->index; |
| 698 | size2 = zh2->size; |
| 699 | memcpy(tmpmem, zbud_data(zh2, size2), size2); |
| 700 | data2 = tmpmem; |
| 701 | } |
| 702 | spin_unlock(&zbpg->lock); |
| 703 | preempt_enable(); |
| 704 | |
| 705 | /* OK, no locks held anymore, remotify one or both zbuds */ |
| 706 | if (zh1 != NULL) |
| 707 | ret = zbud_remotify_zbud(&xh1, data1, size1); |
| 708 | if (zh2 != NULL) |
| 709 | ret |= zbud_remotify_zbud(&xh2, data2, size2); |
| 710 | return ret; |
| 711 | } |
| 712 | |
| 713 | void zbud_remotify_pages(int nr) |
| 714 | { |
| 715 | struct zbud_page *zbpg; |
| 716 | int i, ret; |
| 717 | |
| 718 | /* |
| 719 | * for now just try remotifying unbuddied pages, starting with |
| 720 | * least space avail |
| 721 | */ |
| 722 | for (i = 0; i < MAX_CHUNK; i++) { |
| 723 | retry_unbud_list_i: |
| 724 | preempt_disable(); /* enable in zbud_remotify_zbpg */ |
| 725 | spin_lock_bh(&zbud_budlists_spinlock); |
| 726 | if (list_empty(&zbud_unbuddied[i].list)) { |
| 727 | spin_unlock_bh(&zbud_budlists_spinlock); |
| 728 | preempt_enable(); |
| 729 | continue; /* next i in for loop */ |
| 730 | } |
| 731 | list_for_each_entry(zbpg, &zbud_unbuddied[i].list, bud_list) { |
| 732 | if (unlikely(!spin_trylock(&zbpg->lock))) |
| 733 | continue; /* next list_for_each_entry */ |
| 734 | zbud_unbuddied[i].count--; |
| 735 | /* want budlists unlocked when doing zbpg remotify */ |
| 736 | spin_unlock_bh(&zbud_budlists_spinlock); |
| 737 | ret = zbud_remotify_zbpg(zbpg); |
| 738 | /* preemption is re-enabled in zbud_remotify_zbpg */ |
| 739 | if (ret == 0) { |
| 740 | if (--nr <= 0) |
| 741 | goto out; |
| 742 | goto retry_unbud_list_i; |
| 743 | } |
| 744 | /* if fail to remotify any page, quit */ |
| 745 | pr_err("TESTING zbud_remotify_pages failed on page," |
| 746 | " trying to re-add\n"); |
| 747 | spin_lock_bh(&zbud_budlists_spinlock); |
| 748 | spin_lock(&zbpg->lock); |
| 749 | list_add_tail(&zbpg->bud_list, &zbud_unbuddied[i].list); |
| 750 | zbud_unbuddied[i].count++; |
| 751 | spin_unlock(&zbpg->lock); |
| 752 | spin_unlock_bh(&zbud_budlists_spinlock); |
| 753 | pr_err("TESTING zbud_remotify_pages failed on page," |
| 754 | " finished re-add\n"); |
| 755 | goto out; |
| 756 | } |
| 757 | spin_unlock_bh(&zbud_budlists_spinlock); |
| 758 | preempt_enable(); |
| 759 | } |
| 760 | |
| 761 | next_buddied_zbpg: |
| 762 | preempt_disable(); /* enable in zbud_remotify_zbpg */ |
| 763 | spin_lock_bh(&zbud_budlists_spinlock); |
| 764 | if (list_empty(&zbud_buddied_list)) |
| 765 | goto unlock_out; |
| 766 | list_for_each_entry(zbpg, &zbud_buddied_list, bud_list) { |
| 767 | if (unlikely(!spin_trylock(&zbpg->lock))) |
| 768 | continue; /* next list_for_each_entry */ |
| 769 | zcache_zbud_buddied_count--; |
| 770 | /* want budlists unlocked when doing zbpg remotify */ |
| 771 | spin_unlock_bh(&zbud_budlists_spinlock); |
| 772 | ret = zbud_remotify_zbpg(zbpg); |
| 773 | /* preemption is re-enabled in zbud_remotify_zbpg */ |
| 774 | if (ret == 0) { |
| 775 | if (--nr <= 0) |
| 776 | goto out; |
| 777 | goto next_buddied_zbpg; |
| 778 | } |
| 779 | /* if fail to remotify any page, quit */ |
| 780 | pr_err("TESTING zbud_remotify_pages failed on BUDDIED page," |
| 781 | " trying to re-add\n"); |
| 782 | spin_lock_bh(&zbud_budlists_spinlock); |
| 783 | spin_lock(&zbpg->lock); |
| 784 | list_add_tail(&zbpg->bud_list, &zbud_buddied_list); |
| 785 | zcache_zbud_buddied_count++; |
| 786 | spin_unlock(&zbpg->lock); |
| 787 | spin_unlock_bh(&zbud_budlists_spinlock); |
| 788 | pr_err("TESTING zbud_remotify_pages failed on BUDDIED page," |
| 789 | " finished re-add\n"); |
| 790 | goto out; |
| 791 | } |
| 792 | unlock_out: |
| 793 | spin_unlock_bh(&zbud_budlists_spinlock); |
| 794 | preempt_enable(); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 795 | out: |
| 796 | return; |
| 797 | } |
| 798 | |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 799 | /* the "flush list" asynchronously collects pages to remotely flush */ |
| 800 | #define FLUSH_ENTIRE_OBJECT ((uint32_t)-1) |
| 801 | static void ramster_flnode_free(struct flushlist_node *, |
| 802 | struct tmem_pool *); |
| 803 | |
| 804 | static void zcache_remote_flush_page(struct flushlist_node *flnode) |
| 805 | { |
| 806 | struct tmem_xhandle *xh; |
| 807 | int remotenode, ret; |
| 808 | |
| 809 | preempt_disable(); |
| 810 | xh = &flnode->xh; |
| 811 | remotenode = flnode->xh.client_id; |
| 812 | ret = ramster_remote_flush(xh, remotenode); |
| 813 | if (ret >= 0) |
| 814 | ramster_remote_pages_flushed++; |
| 815 | else |
| 816 | ramster_remote_page_flushes_failed++; |
| 817 | preempt_enable_no_resched(); |
| 818 | ramster_flnode_free(flnode, NULL); |
| 819 | } |
| 820 | |
| 821 | static void zcache_remote_flush_object(struct flushlist_node *flnode) |
| 822 | { |
| 823 | struct tmem_xhandle *xh; |
| 824 | int remotenode, ret; |
| 825 | |
| 826 | preempt_disable(); |
| 827 | xh = &flnode->xh; |
| 828 | remotenode = flnode->xh.client_id; |
| 829 | ret = ramster_remote_flush_object(xh, remotenode); |
| 830 | if (ret >= 0) |
| 831 | ramster_remote_objects_flushed++; |
| 832 | else |
| 833 | ramster_remote_object_flushes_failed++; |
| 834 | preempt_enable_no_resched(); |
| 835 | ramster_flnode_free(flnode, NULL); |
| 836 | } |
| 837 | |
| 838 | static void zcache_remote_eph_put(struct zbud_hdr *zbud) |
| 839 | { |
| 840 | /* FIXME */ |
| 841 | } |
| 842 | |
| 843 | static void zcache_remote_pers_put(struct zv_hdr *zv) |
| 844 | { |
| 845 | struct tmem_xhandle xh; |
| 846 | uint16_t size; |
| 847 | bool ephemeral; |
| 848 | int remotenode, ret = -1; |
| 849 | char *data; |
| 850 | struct tmem_pool *pool; |
| 851 | unsigned long flags; |
| 852 | unsigned char cksum; |
| 853 | char *p; |
| 854 | int i; |
| 855 | unsigned char *tmpmem = __get_cpu_var(zcache_remoteputmem); |
| 856 | |
| 857 | ASSERT_SENTINEL(zv, ZVH); |
| 858 | BUG_ON(zv->client_id != LOCAL_CLIENT); |
| 859 | local_bh_disable(); |
| 860 | xh.client_id = zv->client_id; |
| 861 | xh.pool_id = zv->pool_id; |
| 862 | xh.oid = zv->oid; |
| 863 | xh.index = zv->index; |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 864 | size = xv_get_object_size(zv) - sizeof(*zv); |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 865 | BUG_ON(size == 0 || size > zv_max_page_size); |
| 866 | data = (char *)zv + sizeof(*zv); |
| 867 | for (p = data, cksum = 0, i = 0; i < size; i++) |
| 868 | cksum += *p; |
| 869 | memcpy(tmpmem, data, size); |
| 870 | data = tmpmem; |
| 871 | pool = zcache_get_pool_by_id(zv->client_id, zv->pool_id); |
| 872 | ephemeral = is_ephemeral(pool); |
| 873 | zcache_put_pool(pool); |
| 874 | /* now OK to release lock set in caller */ |
| 875 | spin_unlock(&zcache_rem_op_list_lock); |
| 876 | local_bh_enable(); |
| 877 | preempt_disable(); |
| 878 | ret = ramster_remote_put(&xh, data, size, ephemeral, &remotenode); |
| 879 | preempt_enable_no_resched(); |
| 880 | if (ret != 0) { |
| 881 | /* |
| 882 | * This is some form of a memory leak... if the remote put |
| 883 | * fails, there will never be another attempt to remotify |
| 884 | * this page. But since we've dropped the zv pointer, |
| 885 | * the page may have been freed or the data replaced |
| 886 | * so we can't just "put it back" in the remote op list. |
| 887 | * Even if we could, not sure where to put it in the list |
| 888 | * because there may be flushes that must be strictly |
| 889 | * ordered vs the put. So leave this as a FIXME for now. |
| 890 | * But count them so we know if it becomes a problem. |
| 891 | */ |
| 892 | ramster_pers_pages_remote_failed++; |
| 893 | goto out; |
| 894 | } else |
| 895 | atomic_inc(&ramster_remote_pers_pages); |
| 896 | ramster_pers_pages_remoted++; |
| 897 | /* |
| 898 | * data was successfully remoted so change the local version to |
| 899 | * point to the remote node where it landed |
| 900 | */ |
| 901 | local_bh_disable(); |
| 902 | pool = zcache_get_pool_by_id(LOCAL_CLIENT, xh.pool_id); |
| 903 | local_irq_save(flags); |
| 904 | (void)tmem_replace(pool, &xh.oid, xh.index, |
| 905 | pampd_make_remote(remotenode, size, cksum)); |
| 906 | local_irq_restore(flags); |
| 907 | zcache_put_pool(pool); |
| 908 | local_bh_enable(); |
| 909 | out: |
| 910 | return; |
| 911 | } |
| 912 | |
| 913 | static void zcache_do_remotify_ops(int nr) |
| 914 | { |
| 915 | struct ramster_remotify_hdr *rem_op; |
| 916 | union remotify_list_node *u; |
| 917 | |
| 918 | while (1) { |
| 919 | if (!nr) |
| 920 | goto out; |
| 921 | spin_lock(&zcache_rem_op_list_lock); |
| 922 | if (list_empty(&zcache_rem_op_list)) { |
| 923 | spin_unlock(&zcache_rem_op_list_lock); |
| 924 | goto out; |
| 925 | } |
| 926 | rem_op = list_first_entry(&zcache_rem_op_list, |
| 927 | struct ramster_remotify_hdr, list); |
| 928 | list_del_init(&rem_op->list); |
| 929 | if (rem_op->op != RAMSTER_REMOTIFY_PERS_PUT) |
| 930 | spin_unlock(&zcache_rem_op_list_lock); |
| 931 | u = (union remotify_list_node *)rem_op; |
| 932 | switch (rem_op->op) { |
| 933 | case RAMSTER_REMOTIFY_EPH_PUT: |
| 934 | BUG(); |
| 935 | zcache_remote_eph_put((struct zbud_hdr *)rem_op); |
| 936 | break; |
| 937 | case RAMSTER_REMOTIFY_PERS_PUT: |
| 938 | zcache_remote_pers_put((struct zv_hdr *)rem_op); |
| 939 | break; |
| 940 | case RAMSTER_REMOTIFY_FLUSH_PAGE: |
| 941 | zcache_remote_flush_page((struct flushlist_node *)u); |
| 942 | break; |
| 943 | case RAMSTER_REMOTIFY_FLUSH_OBJ: |
| 944 | zcache_remote_flush_object((struct flushlist_node *)u); |
| 945 | break; |
| 946 | default: |
| 947 | BUG(); |
| 948 | } |
| 949 | } |
| 950 | out: |
| 951 | return; |
| 952 | } |
| 953 | |
| 954 | /* |
| 955 | * Communicate interface revision with userspace |
| 956 | */ |
| 957 | #include "cluster/ramster_nodemanager.h" |
| 958 | static unsigned long ramster_interface_revision = R2NM_API_VERSION; |
| 959 | |
| 960 | /* |
| 961 | * For now, just push over a few pages every few seconds to |
| 962 | * ensure that it basically works |
| 963 | */ |
| 964 | static struct workqueue_struct *ramster_remotify_workqueue; |
| 965 | static void ramster_remotify_process(struct work_struct *work); |
| 966 | static DECLARE_DELAYED_WORK(ramster_remotify_worker, |
| 967 | ramster_remotify_process); |
| 968 | |
| 969 | static void ramster_remotify_queue_delayed_work(unsigned long delay) |
| 970 | { |
| 971 | if (!queue_delayed_work(ramster_remotify_workqueue, |
| 972 | &ramster_remotify_worker, delay)) |
| 973 | pr_err("ramster_remotify: bad workqueue\n"); |
| 974 | } |
| 975 | |
| 976 | |
| 977 | static int use_frontswap; |
| 978 | static int use_cleancache; |
| 979 | static int ramster_remote_target_nodenum = -1; |
| 980 | static void ramster_remotify_process(struct work_struct *work) |
| 981 | { |
| 982 | static bool remotify_in_progress; |
| 983 | |
| 984 | BUG_ON(irqs_disabled()); |
| 985 | if (remotify_in_progress) |
| 986 | ramster_remotify_queue_delayed_work(HZ); |
| 987 | else if (ramster_remote_target_nodenum != -1) { |
| 988 | remotify_in_progress = true; |
| 989 | #ifdef CONFIG_CLEANCACHE |
| 990 | if (use_cleancache && ramster_eph_remotify_enable) |
| 991 | zbud_remotify_pages(5000); /* FIXME is this a good number? */ |
| 992 | #endif |
| 993 | #ifdef CONFIG_FRONTSWAP |
| 994 | if (use_frontswap && ramster_pers_remotify_enable) |
| 995 | zcache_do_remotify_ops(500); /* FIXME is this a good number? */ |
| 996 | #endif |
| 997 | remotify_in_progress = false; |
| 998 | ramster_remotify_queue_delayed_work(HZ); |
| 999 | } |
| 1000 | } |
| 1001 | |
| 1002 | static void ramster_remotify_init(void) |
| 1003 | { |
| 1004 | unsigned long n = 60UL; |
| 1005 | ramster_remotify_workqueue = |
| 1006 | create_singlethread_workqueue("ramster_remotify"); |
| 1007 | ramster_remotify_queue_delayed_work(n * HZ); |
| 1008 | } |
| 1009 | |
| 1010 | |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1011 | static void zbud_init(void) |
| 1012 | { |
| 1013 | int i; |
| 1014 | |
| 1015 | INIT_LIST_HEAD(&zbud_buddied_list); |
| 1016 | zcache_zbud_buddied_count = 0; |
| 1017 | for (i = 0; i < NCHUNKS; i++) { |
| 1018 | INIT_LIST_HEAD(&zbud_unbuddied[i].list); |
| 1019 | zbud_unbuddied[i].count = 0; |
| 1020 | } |
| 1021 | } |
| 1022 | |
| 1023 | #ifdef CONFIG_SYSFS |
| 1024 | /* |
| 1025 | * These sysfs routines show a nice distribution of how many zbpg's are |
| 1026 | * currently (and have ever been placed) in each unbuddied list. It's fun |
| 1027 | * to watch but can probably go away before final merge. |
| 1028 | */ |
| 1029 | static int zbud_show_unbuddied_list_counts(char *buf) |
| 1030 | { |
| 1031 | int i; |
| 1032 | char *p = buf; |
| 1033 | |
| 1034 | for (i = 0; i < NCHUNKS; i++) |
| 1035 | p += sprintf(p, "%u ", zbud_unbuddied[i].count); |
| 1036 | return p - buf; |
| 1037 | } |
| 1038 | |
| 1039 | static int zbud_show_cumul_chunk_counts(char *buf) |
| 1040 | { |
| 1041 | unsigned long i, chunks = 0, total_chunks = 0, sum_total_chunks = 0; |
| 1042 | unsigned long total_chunks_lte_21 = 0, total_chunks_lte_32 = 0; |
| 1043 | unsigned long total_chunks_lte_42 = 0; |
| 1044 | char *p = buf; |
| 1045 | |
| 1046 | for (i = 0; i < NCHUNKS; i++) { |
| 1047 | p += sprintf(p, "%lu ", zbud_cumul_chunk_counts[i]); |
| 1048 | chunks += zbud_cumul_chunk_counts[i]; |
| 1049 | total_chunks += zbud_cumul_chunk_counts[i]; |
| 1050 | sum_total_chunks += i * zbud_cumul_chunk_counts[i]; |
| 1051 | if (i == 21) |
| 1052 | total_chunks_lte_21 = total_chunks; |
| 1053 | if (i == 32) |
| 1054 | total_chunks_lte_32 = total_chunks; |
| 1055 | if (i == 42) |
| 1056 | total_chunks_lte_42 = total_chunks; |
| 1057 | } |
| 1058 | p += sprintf(p, "<=21:%lu <=32:%lu <=42:%lu, mean:%lu\n", |
| 1059 | total_chunks_lte_21, total_chunks_lte_32, total_chunks_lte_42, |
| 1060 | chunks == 0 ? 0 : sum_total_chunks / chunks); |
| 1061 | return p - buf; |
| 1062 | } |
| 1063 | #endif |
| 1064 | |
| 1065 | /********** |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 1066 | * This "zv" PAM implementation combines the TLSF-based xvMalloc |
| 1067 | * with lzo1x compression to maximize the amount of data that can |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1068 | * be packed into a physical page. |
| 1069 | * |
| 1070 | * Zv represents a PAM page with the index and object (plus a "size" value |
| 1071 | * necessary for decompression) immediately preceding the compressed data. |
| 1072 | */ |
| 1073 | |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1074 | /* rudimentary policy limits */ |
| 1075 | /* total number of persistent pages may not exceed this percentage */ |
| 1076 | static unsigned int zv_page_count_policy_percent = 75; |
| 1077 | /* |
| 1078 | * byte count defining poor compression; pages with greater zsize will be |
| 1079 | * rejected |
| 1080 | */ |
| 1081 | static unsigned int zv_max_zsize = (PAGE_SIZE / 8) * 7; |
| 1082 | /* |
| 1083 | * byte count defining poor *mean* compression; pages with greater zsize |
| 1084 | * will be rejected until sufficient better-compressed pages are accepted |
| 1085 | * driving the mean below this threshold |
| 1086 | */ |
| 1087 | static unsigned int zv_max_mean_zsize = (PAGE_SIZE / 8) * 5; |
| 1088 | |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1089 | static atomic_t zv_curr_dist_counts[NCHUNKS]; |
| 1090 | static atomic_t zv_cumul_dist_counts[NCHUNKS]; |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1091 | |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1092 | |
| 1093 | static struct zv_hdr *zv_create(struct zcache_client *cli, uint32_t pool_id, |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1094 | struct tmem_oid *oid, uint32_t index, |
| 1095 | void *cdata, unsigned clen) |
| 1096 | { |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 1097 | struct page *page; |
| 1098 | struct zv_hdr *zv = NULL; |
| 1099 | uint32_t offset; |
| 1100 | int alloc_size = clen + sizeof(struct zv_hdr); |
| 1101 | int chunks = (alloc_size + (CHUNK_SIZE - 1)) >> CHUNK_SHIFT; |
| 1102 | int ret; |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1103 | |
| 1104 | BUG_ON(!irqs_disabled()); |
| 1105 | BUG_ON(chunks >= NCHUNKS); |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 1106 | ret = xv_malloc(cli->xvpool, clen + sizeof(struct zv_hdr), |
| 1107 | &page, &offset, ZCACHE_GFP_MASK); |
| 1108 | if (unlikely(ret)) |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1109 | goto out; |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1110 | atomic_inc(&zv_curr_dist_counts[chunks]); |
| 1111 | atomic_inc(&zv_cumul_dist_counts[chunks]); |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 1112 | zv = kmap_atomic(page) + offset; |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1113 | zv->index = index; |
| 1114 | zv->oid = *oid; |
| 1115 | zv->pool_id = pool_id; |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 1116 | SET_SENTINEL(zv, ZVH); |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1117 | INIT_LIST_HEAD(&zv->rem_op.list); |
| 1118 | zv->client_id = get_client_id_from_client(cli); |
| 1119 | zv->rem_op.op = RAMSTER_REMOTIFY_PERS_PUT; |
| 1120 | if (zv->client_id == LOCAL_CLIENT) { |
| 1121 | spin_lock(&zcache_rem_op_list_lock); |
| 1122 | list_add_tail(&zv->rem_op.list, &zcache_rem_op_list); |
| 1123 | spin_unlock(&zcache_rem_op_list_lock); |
| 1124 | } |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1125 | memcpy((char *)zv + sizeof(struct zv_hdr), cdata, clen); |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 1126 | kunmap_atomic(zv); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1127 | out: |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 1128 | return zv; |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1129 | } |
| 1130 | |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1131 | /* similar to zv_create, but just reserve space, no data yet */ |
| 1132 | static struct zv_hdr *zv_alloc(struct tmem_pool *pool, |
| 1133 | struct tmem_oid *oid, uint32_t index, |
| 1134 | unsigned clen) |
| 1135 | { |
| 1136 | struct zcache_client *cli = pool->client; |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 1137 | struct page *page; |
| 1138 | struct zv_hdr *zv = NULL; |
| 1139 | uint32_t offset; |
| 1140 | int ret; |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1141 | |
| 1142 | BUG_ON(!irqs_disabled()); |
| 1143 | BUG_ON(!is_local_client(pool->client)); |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 1144 | ret = xv_malloc(cli->xvpool, clen + sizeof(struct zv_hdr), |
| 1145 | &page, &offset, ZCACHE_GFP_MASK); |
| 1146 | if (unlikely(ret)) |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1147 | goto out; |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 1148 | zv = kmap_atomic(page) + offset; |
| 1149 | SET_SENTINEL(zv, ZVH); |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1150 | INIT_LIST_HEAD(&zv->rem_op.list); |
| 1151 | zv->client_id = LOCAL_CLIENT; |
| 1152 | zv->rem_op.op = RAMSTER_INTRANSIT_PERS; |
| 1153 | zv->index = index; |
| 1154 | zv->oid = *oid; |
| 1155 | zv->pool_id = pool->pool_id; |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 1156 | kunmap_atomic(zv); |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1157 | out: |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 1158 | return zv; |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1159 | } |
| 1160 | |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 1161 | static void zv_free(struct xv_pool *xvpool, struct zv_hdr *zv) |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1162 | { |
| 1163 | unsigned long flags; |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 1164 | struct page *page; |
| 1165 | uint32_t offset; |
| 1166 | uint16_t size = xv_get_object_size(zv); |
| 1167 | int chunks = (size + (CHUNK_SIZE - 1)) >> CHUNK_SHIFT; |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1168 | |
| 1169 | ASSERT_SENTINEL(zv, ZVH); |
| 1170 | BUG_ON(chunks >= NCHUNKS); |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1171 | atomic_dec(&zv_curr_dist_counts[chunks]); |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 1172 | size -= sizeof(*zv); |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1173 | spin_lock(&zcache_rem_op_list_lock); |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 1174 | size = xv_get_object_size(zv) - sizeof(*zv); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1175 | BUG_ON(size == 0); |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 1176 | INVERT_SENTINEL(zv, ZVH); |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1177 | if (!list_empty(&zv->rem_op.list)) |
| 1178 | list_del_init(&zv->rem_op.list); |
| 1179 | spin_unlock(&zcache_rem_op_list_lock); |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 1180 | page = virt_to_page(zv); |
| 1181 | offset = (unsigned long)zv & ~PAGE_MASK; |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1182 | local_irq_save(flags); |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 1183 | xv_free(xvpool, page, offset); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1184 | local_irq_restore(flags); |
| 1185 | } |
| 1186 | |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 1187 | static void zv_decompress(struct page *page, struct zv_hdr *zv) |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1188 | { |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 1189 | size_t clen = PAGE_SIZE; |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1190 | char *to_va; |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 1191 | unsigned size; |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1192 | int ret; |
| 1193 | |
| 1194 | ASSERT_SENTINEL(zv, ZVH); |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 1195 | size = xv_get_object_size(zv) - sizeof(*zv); |
| 1196 | BUG_ON(size == 0); |
Linus Torvalds | 9f39383 | 2012-03-21 09:40:26 -0700 | [diff] [blame] | 1197 | to_va = kmap_atomic(page); |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 1198 | ret = lzo1x_decompress_safe((char *)zv + sizeof(*zv), |
| 1199 | size, to_va, &clen); |
Linus Torvalds | 9f39383 | 2012-03-21 09:40:26 -0700 | [diff] [blame] | 1200 | kunmap_atomic(to_va); |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 1201 | BUG_ON(ret != LZO_E_OK); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1202 | BUG_ON(clen != PAGE_SIZE); |
| 1203 | } |
| 1204 | |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1205 | static void zv_copy_from_pampd(char *data, size_t *bufsize, struct zv_hdr *zv) |
| 1206 | { |
| 1207 | unsigned size; |
| 1208 | |
| 1209 | ASSERT_SENTINEL(zv, ZVH); |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 1210 | size = xv_get_object_size(zv) - sizeof(*zv); |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1211 | BUG_ON(size == 0 || size > zv_max_page_size); |
| 1212 | BUG_ON(size > *bufsize); |
| 1213 | memcpy(data, (char *)zv + sizeof(*zv), size); |
| 1214 | *bufsize = size; |
| 1215 | } |
| 1216 | |
| 1217 | static void zv_copy_to_pampd(struct zv_hdr *zv, char *data, size_t size) |
| 1218 | { |
| 1219 | unsigned zv_size; |
| 1220 | |
| 1221 | ASSERT_SENTINEL(zv, ZVH); |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 1222 | zv_size = xv_get_object_size(zv) - sizeof(*zv); |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1223 | BUG_ON(zv_size != size); |
| 1224 | BUG_ON(zv_size == 0 || zv_size > zv_max_page_size); |
| 1225 | memcpy((char *)zv + sizeof(*zv), data, size); |
| 1226 | } |
| 1227 | |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1228 | #ifdef CONFIG_SYSFS |
| 1229 | /* |
| 1230 | * show a distribution of compression stats for zv pages. |
| 1231 | */ |
| 1232 | |
| 1233 | static int zv_curr_dist_counts_show(char *buf) |
| 1234 | { |
| 1235 | unsigned long i, n, chunks = 0, sum_total_chunks = 0; |
| 1236 | char *p = buf; |
| 1237 | |
| 1238 | for (i = 0; i < NCHUNKS; i++) { |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1239 | n = atomic_read(&zv_curr_dist_counts[i]); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1240 | p += sprintf(p, "%lu ", n); |
| 1241 | chunks += n; |
| 1242 | sum_total_chunks += i * n; |
| 1243 | } |
| 1244 | p += sprintf(p, "mean:%lu\n", |
| 1245 | chunks == 0 ? 0 : sum_total_chunks / chunks); |
| 1246 | return p - buf; |
| 1247 | } |
| 1248 | |
| 1249 | static int zv_cumul_dist_counts_show(char *buf) |
| 1250 | { |
| 1251 | unsigned long i, n, chunks = 0, sum_total_chunks = 0; |
| 1252 | char *p = buf; |
| 1253 | |
| 1254 | for (i = 0; i < NCHUNKS; i++) { |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1255 | n = atomic_read(&zv_cumul_dist_counts[i]); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1256 | p += sprintf(p, "%lu ", n); |
| 1257 | chunks += n; |
| 1258 | sum_total_chunks += i * n; |
| 1259 | } |
| 1260 | p += sprintf(p, "mean:%lu\n", |
| 1261 | chunks == 0 ? 0 : sum_total_chunks / chunks); |
| 1262 | return p - buf; |
| 1263 | } |
| 1264 | |
| 1265 | /* |
| 1266 | * setting zv_max_zsize via sysfs causes all persistent (e.g. swap) |
| 1267 | * pages that don't compress to less than this value (including metadata |
| 1268 | * overhead) to be rejected. We don't allow the value to get too close |
| 1269 | * to PAGE_SIZE. |
| 1270 | */ |
| 1271 | static ssize_t zv_max_zsize_show(struct kobject *kobj, |
| 1272 | struct kobj_attribute *attr, |
| 1273 | char *buf) |
| 1274 | { |
| 1275 | return sprintf(buf, "%u\n", zv_max_zsize); |
| 1276 | } |
| 1277 | |
| 1278 | static ssize_t zv_max_zsize_store(struct kobject *kobj, |
| 1279 | struct kobj_attribute *attr, |
| 1280 | const char *buf, size_t count) |
| 1281 | { |
| 1282 | unsigned long val; |
| 1283 | int err; |
| 1284 | |
| 1285 | if (!capable(CAP_SYS_ADMIN)) |
| 1286 | return -EPERM; |
| 1287 | |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1288 | err = kstrtoul(buf, 10, &val); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1289 | if (err || (val == 0) || (val > (PAGE_SIZE / 8) * 7)) |
| 1290 | return -EINVAL; |
| 1291 | zv_max_zsize = val; |
| 1292 | return count; |
| 1293 | } |
| 1294 | |
| 1295 | /* |
| 1296 | * setting zv_max_mean_zsize via sysfs causes all persistent (e.g. swap) |
| 1297 | * pages that don't compress to less than this value (including metadata |
| 1298 | * overhead) to be rejected UNLESS the mean compression is also smaller |
| 1299 | * than this value. In other words, we are load-balancing-by-zsize the |
| 1300 | * accepted pages. Again, we don't allow the value to get too close |
| 1301 | * to PAGE_SIZE. |
| 1302 | */ |
| 1303 | static ssize_t zv_max_mean_zsize_show(struct kobject *kobj, |
| 1304 | struct kobj_attribute *attr, |
| 1305 | char *buf) |
| 1306 | { |
| 1307 | return sprintf(buf, "%u\n", zv_max_mean_zsize); |
| 1308 | } |
| 1309 | |
| 1310 | static ssize_t zv_max_mean_zsize_store(struct kobject *kobj, |
| 1311 | struct kobj_attribute *attr, |
| 1312 | const char *buf, size_t count) |
| 1313 | { |
| 1314 | unsigned long val; |
| 1315 | int err; |
| 1316 | |
| 1317 | if (!capable(CAP_SYS_ADMIN)) |
| 1318 | return -EPERM; |
| 1319 | |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1320 | err = kstrtoul(buf, 10, &val); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1321 | if (err || (val == 0) || (val > (PAGE_SIZE / 8) * 7)) |
| 1322 | return -EINVAL; |
| 1323 | zv_max_mean_zsize = val; |
| 1324 | return count; |
| 1325 | } |
| 1326 | |
| 1327 | /* |
| 1328 | * setting zv_page_count_policy_percent via sysfs sets an upper bound of |
| 1329 | * persistent (e.g. swap) pages that will be retained according to: |
| 1330 | * (zv_page_count_policy_percent * totalram_pages) / 100) |
| 1331 | * when that limit is reached, further puts will be rejected (until |
| 1332 | * some pages have been flushed). Note that, due to compression, |
| 1333 | * this number may exceed 100; it defaults to 75 and we set an |
Masanari Iida | 01fdf90 | 2012-05-08 00:26:07 +0900 | [diff] [blame] | 1334 | * arbitrary limit of 150. A poor choice will almost certainly result |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1335 | * in OOM's, so this value should only be changed prudently. |
| 1336 | */ |
| 1337 | static ssize_t zv_page_count_policy_percent_show(struct kobject *kobj, |
| 1338 | struct kobj_attribute *attr, |
| 1339 | char *buf) |
| 1340 | { |
| 1341 | return sprintf(buf, "%u\n", zv_page_count_policy_percent); |
| 1342 | } |
| 1343 | |
| 1344 | static ssize_t zv_page_count_policy_percent_store(struct kobject *kobj, |
| 1345 | struct kobj_attribute *attr, |
| 1346 | const char *buf, size_t count) |
| 1347 | { |
| 1348 | unsigned long val; |
| 1349 | int err; |
| 1350 | |
| 1351 | if (!capable(CAP_SYS_ADMIN)) |
| 1352 | return -EPERM; |
| 1353 | |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1354 | err = kstrtoul(buf, 10, &val); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1355 | if (err || (val == 0) || (val > 150)) |
| 1356 | return -EINVAL; |
| 1357 | zv_page_count_policy_percent = val; |
| 1358 | return count; |
| 1359 | } |
| 1360 | |
| 1361 | static struct kobj_attribute zcache_zv_max_zsize_attr = { |
| 1362 | .attr = { .name = "zv_max_zsize", .mode = 0644 }, |
| 1363 | .show = zv_max_zsize_show, |
| 1364 | .store = zv_max_zsize_store, |
| 1365 | }; |
| 1366 | |
| 1367 | static struct kobj_attribute zcache_zv_max_mean_zsize_attr = { |
| 1368 | .attr = { .name = "zv_max_mean_zsize", .mode = 0644 }, |
| 1369 | .show = zv_max_mean_zsize_show, |
| 1370 | .store = zv_max_mean_zsize_store, |
| 1371 | }; |
| 1372 | |
| 1373 | static struct kobj_attribute zcache_zv_page_count_policy_percent_attr = { |
| 1374 | .attr = { .name = "zv_page_count_policy_percent", |
| 1375 | .mode = 0644 }, |
| 1376 | .show = zv_page_count_policy_percent_show, |
| 1377 | .store = zv_page_count_policy_percent_store, |
| 1378 | }; |
| 1379 | #endif |
| 1380 | |
| 1381 | /* |
| 1382 | * zcache core code starts here |
| 1383 | */ |
| 1384 | |
| 1385 | /* useful stats not collected by cleancache or frontswap */ |
| 1386 | static unsigned long zcache_flush_total; |
| 1387 | static unsigned long zcache_flush_found; |
| 1388 | static unsigned long zcache_flobj_total; |
| 1389 | static unsigned long zcache_flobj_found; |
| 1390 | static unsigned long zcache_failed_eph_puts; |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1391 | static unsigned long zcache_nonactive_puts; |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1392 | static unsigned long zcache_failed_pers_puts; |
| 1393 | |
| 1394 | /* |
| 1395 | * Tmem operations assume the poolid implies the invoking client. |
| 1396 | * Zcache only has one client (the kernel itself): LOCAL_CLIENT. |
| 1397 | * RAMster has each client numbered by cluster node, and a KVM version |
| 1398 | * of zcache would have one client per guest and each client might |
| 1399 | * have a poolid==N. |
| 1400 | */ |
| 1401 | static struct tmem_pool *zcache_get_pool_by_id(uint16_t cli_id, uint16_t poolid) |
| 1402 | { |
| 1403 | struct tmem_pool *pool = NULL; |
| 1404 | struct zcache_client *cli = NULL; |
| 1405 | |
| 1406 | if (cli_id == LOCAL_CLIENT) |
| 1407 | cli = &zcache_host; |
| 1408 | else { |
| 1409 | if (cli_id >= MAX_CLIENTS) |
| 1410 | goto out; |
| 1411 | cli = &zcache_clients[cli_id]; |
| 1412 | if (cli == NULL) |
| 1413 | goto out; |
| 1414 | atomic_inc(&cli->refcount); |
| 1415 | } |
| 1416 | if (poolid < MAX_POOLS_PER_CLIENT) { |
| 1417 | pool = cli->tmem_pools[poolid]; |
| 1418 | if (pool != NULL) |
| 1419 | atomic_inc(&pool->refcount); |
| 1420 | } |
| 1421 | out: |
| 1422 | return pool; |
| 1423 | } |
| 1424 | |
| 1425 | static void zcache_put_pool(struct tmem_pool *pool) |
| 1426 | { |
| 1427 | struct zcache_client *cli = NULL; |
| 1428 | |
| 1429 | if (pool == NULL) |
| 1430 | BUG(); |
| 1431 | cli = pool->client; |
| 1432 | atomic_dec(&pool->refcount); |
| 1433 | atomic_dec(&cli->refcount); |
| 1434 | } |
| 1435 | |
| 1436 | int zcache_new_client(uint16_t cli_id) |
| 1437 | { |
| 1438 | struct zcache_client *cli = NULL; |
| 1439 | int ret = -1; |
| 1440 | |
| 1441 | if (cli_id == LOCAL_CLIENT) |
| 1442 | cli = &zcache_host; |
| 1443 | else if ((unsigned int)cli_id < MAX_CLIENTS) |
| 1444 | cli = &zcache_clients[cli_id]; |
| 1445 | if (cli == NULL) |
| 1446 | goto out; |
| 1447 | if (cli->allocated) |
| 1448 | goto out; |
| 1449 | cli->allocated = 1; |
| 1450 | #ifdef CONFIG_FRONTSWAP |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 1451 | cli->xvpool = xv_create_pool(); |
| 1452 | if (cli->xvpool == NULL) |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1453 | goto out; |
| 1454 | #endif |
| 1455 | ret = 0; |
| 1456 | out: |
| 1457 | return ret; |
| 1458 | } |
| 1459 | |
| 1460 | /* counters for debugging */ |
| 1461 | static unsigned long zcache_failed_get_free_pages; |
| 1462 | static unsigned long zcache_failed_alloc; |
| 1463 | static unsigned long zcache_put_to_flush; |
| 1464 | |
| 1465 | /* |
| 1466 | * for now, used named slabs so can easily track usage; later can |
| 1467 | * either just use kmalloc, or perhaps add a slab-like allocator |
| 1468 | * to more carefully manage total memory utilization |
| 1469 | */ |
| 1470 | static struct kmem_cache *zcache_objnode_cache; |
| 1471 | static struct kmem_cache *zcache_obj_cache; |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1472 | static struct kmem_cache *ramster_flnode_cache; |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1473 | static atomic_t zcache_curr_obj_count = ATOMIC_INIT(0); |
| 1474 | static unsigned long zcache_curr_obj_count_max; |
| 1475 | static atomic_t zcache_curr_objnode_count = ATOMIC_INIT(0); |
| 1476 | static unsigned long zcache_curr_objnode_count_max; |
| 1477 | |
| 1478 | /* |
| 1479 | * to avoid memory allocation recursion (e.g. due to direct reclaim), we |
| 1480 | * preload all necessary data structures so the hostops callbacks never |
| 1481 | * actually do a malloc |
| 1482 | */ |
| 1483 | struct zcache_preload { |
| 1484 | void *page; |
| 1485 | struct tmem_obj *obj; |
| 1486 | int nr; |
| 1487 | struct tmem_objnode *objnodes[OBJNODE_TREE_MAX_PATH]; |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1488 | struct flushlist_node *flnode; |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1489 | }; |
| 1490 | static DEFINE_PER_CPU(struct zcache_preload, zcache_preloads) = { 0, }; |
| 1491 | |
| 1492 | static int zcache_do_preload(struct tmem_pool *pool) |
| 1493 | { |
| 1494 | struct zcache_preload *kp; |
| 1495 | struct tmem_objnode *objnode; |
| 1496 | struct tmem_obj *obj; |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1497 | struct flushlist_node *flnode; |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1498 | void *page; |
| 1499 | int ret = -ENOMEM; |
| 1500 | |
| 1501 | if (unlikely(zcache_objnode_cache == NULL)) |
| 1502 | goto out; |
| 1503 | if (unlikely(zcache_obj_cache == NULL)) |
| 1504 | goto out; |
| 1505 | preempt_disable(); |
| 1506 | kp = &__get_cpu_var(zcache_preloads); |
| 1507 | while (kp->nr < ARRAY_SIZE(kp->objnodes)) { |
| 1508 | preempt_enable_no_resched(); |
| 1509 | objnode = kmem_cache_alloc(zcache_objnode_cache, |
| 1510 | ZCACHE_GFP_MASK); |
| 1511 | if (unlikely(objnode == NULL)) { |
| 1512 | zcache_failed_alloc++; |
| 1513 | goto out; |
| 1514 | } |
| 1515 | preempt_disable(); |
| 1516 | kp = &__get_cpu_var(zcache_preloads); |
| 1517 | if (kp->nr < ARRAY_SIZE(kp->objnodes)) |
| 1518 | kp->objnodes[kp->nr++] = objnode; |
| 1519 | else |
| 1520 | kmem_cache_free(zcache_objnode_cache, objnode); |
| 1521 | } |
| 1522 | preempt_enable_no_resched(); |
| 1523 | obj = kmem_cache_alloc(zcache_obj_cache, ZCACHE_GFP_MASK); |
| 1524 | if (unlikely(obj == NULL)) { |
| 1525 | zcache_failed_alloc++; |
| 1526 | goto out; |
| 1527 | } |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1528 | flnode = kmem_cache_alloc(ramster_flnode_cache, ZCACHE_GFP_MASK); |
| 1529 | if (unlikely(flnode == NULL)) { |
| 1530 | zcache_failed_alloc++; |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1531 | goto out; |
| 1532 | } |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1533 | if (is_ephemeral(pool)) { |
| 1534 | page = (void *)__get_free_page(ZCACHE_GFP_MASK); |
| 1535 | if (unlikely(page == NULL)) { |
| 1536 | zcache_failed_get_free_pages++; |
| 1537 | kmem_cache_free(zcache_obj_cache, obj); |
| 1538 | kmem_cache_free(ramster_flnode_cache, flnode); |
| 1539 | goto out; |
| 1540 | } |
| 1541 | } |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1542 | preempt_disable(); |
| 1543 | kp = &__get_cpu_var(zcache_preloads); |
| 1544 | if (kp->obj == NULL) |
| 1545 | kp->obj = obj; |
| 1546 | else |
| 1547 | kmem_cache_free(zcache_obj_cache, obj); |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1548 | if (kp->flnode == NULL) |
| 1549 | kp->flnode = flnode; |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1550 | else |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1551 | kmem_cache_free(ramster_flnode_cache, flnode); |
| 1552 | if (is_ephemeral(pool)) { |
| 1553 | if (kp->page == NULL) |
| 1554 | kp->page = page; |
| 1555 | else |
| 1556 | free_page((unsigned long)page); |
| 1557 | } |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1558 | ret = 0; |
| 1559 | out: |
| 1560 | return ret; |
| 1561 | } |
| 1562 | |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1563 | static int ramster_do_preload_flnode_only(struct tmem_pool *pool) |
| 1564 | { |
| 1565 | struct zcache_preload *kp; |
| 1566 | struct flushlist_node *flnode; |
| 1567 | int ret = -ENOMEM; |
| 1568 | |
| 1569 | BUG_ON(!irqs_disabled()); |
| 1570 | if (unlikely(ramster_flnode_cache == NULL)) |
| 1571 | BUG(); |
| 1572 | kp = &__get_cpu_var(zcache_preloads); |
| 1573 | flnode = kmem_cache_alloc(ramster_flnode_cache, GFP_ATOMIC); |
| 1574 | if (unlikely(flnode == NULL) && kp->flnode == NULL) |
| 1575 | BUG(); /* FIXME handle more gracefully, but how??? */ |
| 1576 | else if (kp->flnode == NULL) |
| 1577 | kp->flnode = flnode; |
| 1578 | else |
| 1579 | kmem_cache_free(ramster_flnode_cache, flnode); |
| 1580 | return ret; |
| 1581 | } |
| 1582 | |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1583 | static void *zcache_get_free_page(void) |
| 1584 | { |
| 1585 | struct zcache_preload *kp; |
| 1586 | void *page; |
| 1587 | |
| 1588 | kp = &__get_cpu_var(zcache_preloads); |
| 1589 | page = kp->page; |
| 1590 | BUG_ON(page == NULL); |
| 1591 | kp->page = NULL; |
| 1592 | return page; |
| 1593 | } |
| 1594 | |
| 1595 | static void zcache_free_page(void *p) |
| 1596 | { |
| 1597 | free_page((unsigned long)p); |
| 1598 | } |
| 1599 | |
| 1600 | /* |
| 1601 | * zcache implementation for tmem host ops |
| 1602 | */ |
| 1603 | |
| 1604 | static struct tmem_objnode *zcache_objnode_alloc(struct tmem_pool *pool) |
| 1605 | { |
| 1606 | struct tmem_objnode *objnode = NULL; |
| 1607 | unsigned long count; |
| 1608 | struct zcache_preload *kp; |
| 1609 | |
| 1610 | kp = &__get_cpu_var(zcache_preloads); |
| 1611 | if (kp->nr <= 0) |
| 1612 | goto out; |
| 1613 | objnode = kp->objnodes[kp->nr - 1]; |
| 1614 | BUG_ON(objnode == NULL); |
| 1615 | kp->objnodes[kp->nr - 1] = NULL; |
| 1616 | kp->nr--; |
| 1617 | count = atomic_inc_return(&zcache_curr_objnode_count); |
| 1618 | if (count > zcache_curr_objnode_count_max) |
| 1619 | zcache_curr_objnode_count_max = count; |
| 1620 | out: |
| 1621 | return objnode; |
| 1622 | } |
| 1623 | |
| 1624 | static void zcache_objnode_free(struct tmem_objnode *objnode, |
| 1625 | struct tmem_pool *pool) |
| 1626 | { |
| 1627 | atomic_dec(&zcache_curr_objnode_count); |
| 1628 | BUG_ON(atomic_read(&zcache_curr_objnode_count) < 0); |
| 1629 | kmem_cache_free(zcache_objnode_cache, objnode); |
| 1630 | } |
| 1631 | |
| 1632 | static struct tmem_obj *zcache_obj_alloc(struct tmem_pool *pool) |
| 1633 | { |
| 1634 | struct tmem_obj *obj = NULL; |
| 1635 | unsigned long count; |
| 1636 | struct zcache_preload *kp; |
| 1637 | |
| 1638 | kp = &__get_cpu_var(zcache_preloads); |
| 1639 | obj = kp->obj; |
| 1640 | BUG_ON(obj == NULL); |
| 1641 | kp->obj = NULL; |
| 1642 | count = atomic_inc_return(&zcache_curr_obj_count); |
| 1643 | if (count > zcache_curr_obj_count_max) |
| 1644 | zcache_curr_obj_count_max = count; |
| 1645 | return obj; |
| 1646 | } |
| 1647 | |
| 1648 | static void zcache_obj_free(struct tmem_obj *obj, struct tmem_pool *pool) |
| 1649 | { |
| 1650 | atomic_dec(&zcache_curr_obj_count); |
| 1651 | BUG_ON(atomic_read(&zcache_curr_obj_count) < 0); |
| 1652 | kmem_cache_free(zcache_obj_cache, obj); |
| 1653 | } |
| 1654 | |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1655 | static struct flushlist_node *ramster_flnode_alloc(struct tmem_pool *pool) |
| 1656 | { |
| 1657 | struct flushlist_node *flnode = NULL; |
| 1658 | struct zcache_preload *kp; |
| 1659 | int count; |
| 1660 | |
| 1661 | kp = &__get_cpu_var(zcache_preloads); |
| 1662 | flnode = kp->flnode; |
| 1663 | BUG_ON(flnode == NULL); |
| 1664 | kp->flnode = NULL; |
| 1665 | count = atomic_inc_return(&ramster_curr_flnode_count); |
| 1666 | if (count > ramster_curr_flnode_count_max) |
| 1667 | ramster_curr_flnode_count_max = count; |
| 1668 | return flnode; |
| 1669 | } |
| 1670 | |
| 1671 | static void ramster_flnode_free(struct flushlist_node *flnode, |
| 1672 | struct tmem_pool *pool) |
| 1673 | { |
| 1674 | atomic_dec(&ramster_curr_flnode_count); |
| 1675 | BUG_ON(atomic_read(&ramster_curr_flnode_count) < 0); |
| 1676 | kmem_cache_free(ramster_flnode_cache, flnode); |
| 1677 | } |
| 1678 | |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1679 | static struct tmem_hostops zcache_hostops = { |
| 1680 | .obj_alloc = zcache_obj_alloc, |
| 1681 | .obj_free = zcache_obj_free, |
| 1682 | .objnode_alloc = zcache_objnode_alloc, |
| 1683 | .objnode_free = zcache_objnode_free, |
| 1684 | }; |
| 1685 | |
| 1686 | /* |
| 1687 | * zcache implementations for PAM page descriptor ops |
| 1688 | */ |
| 1689 | |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1690 | |
| 1691 | static inline void dec_and_check(atomic_t *pvar) |
| 1692 | { |
| 1693 | atomic_dec(pvar); |
| 1694 | /* later when all accounting is fixed, make this a BUG */ |
| 1695 | WARN_ON_ONCE(atomic_read(pvar) < 0); |
| 1696 | } |
| 1697 | |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1698 | static atomic_t zcache_curr_eph_pampd_count = ATOMIC_INIT(0); |
| 1699 | static unsigned long zcache_curr_eph_pampd_count_max; |
| 1700 | static atomic_t zcache_curr_pers_pampd_count = ATOMIC_INIT(0); |
| 1701 | static unsigned long zcache_curr_pers_pampd_count_max; |
| 1702 | |
| 1703 | /* forward reference */ |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 1704 | static int zcache_compress(struct page *from, void **out_va, size_t *out_len); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1705 | |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1706 | static int zcache_pampd_eph_create(char *data, size_t size, bool raw, |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1707 | struct tmem_pool *pool, struct tmem_oid *oid, |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1708 | uint32_t index, void **pampd) |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1709 | { |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1710 | int ret = -1; |
| 1711 | void *cdata = data; |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 1712 | size_t clen = size; |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1713 | struct zcache_client *cli = pool->client; |
| 1714 | uint16_t client_id = get_client_id_from_client(cli); |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1715 | struct page *page = NULL; |
| 1716 | unsigned long count; |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1717 | |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1718 | if (!raw) { |
| 1719 | page = virt_to_page(data); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1720 | ret = zcache_compress(page, &cdata, &clen); |
| 1721 | if (ret == 0) |
| 1722 | goto out; |
| 1723 | if (clen == 0 || clen > zbud_max_buddy_size()) { |
| 1724 | zcache_compress_poor++; |
| 1725 | goto out; |
| 1726 | } |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1727 | } |
| 1728 | *pampd = (void *)zbud_create(client_id, pool->pool_id, oid, |
| 1729 | index, page, cdata, clen); |
| 1730 | if (*pampd == NULL) { |
| 1731 | ret = -ENOMEM; |
| 1732 | goto out; |
| 1733 | } |
| 1734 | ret = 0; |
| 1735 | count = atomic_inc_return(&zcache_curr_eph_pampd_count); |
| 1736 | if (count > zcache_curr_eph_pampd_count_max) |
| 1737 | zcache_curr_eph_pampd_count_max = count; |
| 1738 | if (client_id != LOCAL_CLIENT) { |
| 1739 | count = atomic_inc_return(&ramster_foreign_eph_pampd_count); |
| 1740 | if (count > ramster_foreign_eph_pampd_count_max) |
| 1741 | ramster_foreign_eph_pampd_count_max = count; |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1742 | } |
| 1743 | out: |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1744 | return ret; |
| 1745 | } |
| 1746 | |
| 1747 | static int zcache_pampd_pers_create(char *data, size_t size, bool raw, |
| 1748 | struct tmem_pool *pool, struct tmem_oid *oid, |
| 1749 | uint32_t index, void **pampd) |
| 1750 | { |
| 1751 | int ret = -1; |
| 1752 | void *cdata = data; |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 1753 | size_t clen = size; |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1754 | struct zcache_client *cli = pool->client; |
| 1755 | struct page *page; |
| 1756 | unsigned long count; |
| 1757 | unsigned long zv_mean_zsize; |
| 1758 | struct zv_hdr *zv; |
| 1759 | long curr_pers_pampd_count; |
| 1760 | u64 total_zsize; |
| 1761 | #ifdef RAMSTER_TESTING |
| 1762 | static bool pampd_neg_warned; |
| 1763 | #endif |
| 1764 | |
| 1765 | curr_pers_pampd_count = atomic_read(&zcache_curr_pers_pampd_count) - |
| 1766 | atomic_read(&ramster_remote_pers_pages); |
| 1767 | #ifdef RAMSTER_TESTING |
| 1768 | /* should always be positive, but warn if accounting is off */ |
| 1769 | if (!pampd_neg_warned) { |
| 1770 | pr_warn("ramster: bad accounting for curr_pers_pampd_count\n"); |
| 1771 | pampd_neg_warned = true; |
| 1772 | } |
| 1773 | #endif |
| 1774 | if (curr_pers_pampd_count > |
| 1775 | (zv_page_count_policy_percent * totalram_pages) / 100) { |
| 1776 | zcache_policy_percent_exceeded++; |
| 1777 | goto out; |
| 1778 | } |
| 1779 | if (raw) |
| 1780 | goto ok_to_create; |
| 1781 | page = virt_to_page(data); |
| 1782 | if (zcache_compress(page, &cdata, &clen) == 0) |
| 1783 | goto out; |
| 1784 | /* reject if compression is too poor */ |
| 1785 | if (clen > zv_max_zsize) { |
| 1786 | zcache_compress_poor++; |
| 1787 | goto out; |
| 1788 | } |
| 1789 | /* reject if mean compression is too poor */ |
| 1790 | if ((clen > zv_max_mean_zsize) && (curr_pers_pampd_count > 0)) { |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 1791 | total_zsize = xv_get_total_size_bytes(cli->xvpool); |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1792 | zv_mean_zsize = div_u64(total_zsize, curr_pers_pampd_count); |
| 1793 | if (zv_mean_zsize > zv_max_mean_zsize) { |
| 1794 | zcache_mean_compress_poor++; |
| 1795 | goto out; |
| 1796 | } |
| 1797 | } |
| 1798 | ok_to_create: |
| 1799 | *pampd = (void *)zv_create(cli, pool->pool_id, oid, index, cdata, clen); |
| 1800 | if (*pampd == NULL) { |
| 1801 | ret = -ENOMEM; |
| 1802 | goto out; |
| 1803 | } |
| 1804 | ret = 0; |
| 1805 | count = atomic_inc_return(&zcache_curr_pers_pampd_count); |
| 1806 | if (count > zcache_curr_pers_pampd_count_max) |
| 1807 | zcache_curr_pers_pampd_count_max = count; |
| 1808 | if (is_local_client(cli)) |
| 1809 | goto out; |
| 1810 | zv = *(struct zv_hdr **)pampd; |
| 1811 | count = atomic_inc_return(&ramster_foreign_pers_pampd_count); |
| 1812 | if (count > ramster_foreign_pers_pampd_count_max) |
| 1813 | ramster_foreign_pers_pampd_count_max = count; |
| 1814 | out: |
| 1815 | return ret; |
| 1816 | } |
| 1817 | |
| 1818 | static void *zcache_pampd_create(char *data, size_t size, bool raw, int eph, |
| 1819 | struct tmem_pool *pool, struct tmem_oid *oid, |
| 1820 | uint32_t index) |
| 1821 | { |
| 1822 | void *pampd = NULL; |
| 1823 | int ret; |
| 1824 | bool ephemeral; |
| 1825 | |
| 1826 | BUG_ON(preemptible()); |
| 1827 | ephemeral = (eph == 1) || ((eph == 0) && is_ephemeral(pool)); |
| 1828 | if (ephemeral) |
| 1829 | ret = zcache_pampd_eph_create(data, size, raw, pool, |
| 1830 | oid, index, &pampd); |
| 1831 | else |
| 1832 | ret = zcache_pampd_pers_create(data, size, raw, pool, |
| 1833 | oid, index, &pampd); |
| 1834 | /* FIXME add some counters here for failed creates? */ |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1835 | return pampd; |
| 1836 | } |
| 1837 | |
| 1838 | /* |
| 1839 | * fill the pageframe corresponding to the struct page with the data |
| 1840 | * from the passed pampd |
| 1841 | */ |
| 1842 | static int zcache_pampd_get_data(char *data, size_t *bufsize, bool raw, |
| 1843 | void *pampd, struct tmem_pool *pool, |
| 1844 | struct tmem_oid *oid, uint32_t index) |
| 1845 | { |
| 1846 | int ret = 0; |
| 1847 | |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1848 | BUG_ON(preemptible()); |
| 1849 | BUG_ON(is_ephemeral(pool)); /* Fix later for shared pools? */ |
| 1850 | BUG_ON(pampd_is_remote(pampd)); |
| 1851 | if (raw) |
| 1852 | zv_copy_from_pampd(data, bufsize, pampd); |
| 1853 | else |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 1854 | zv_decompress(virt_to_page(data), pampd); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1855 | return ret; |
| 1856 | } |
| 1857 | |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1858 | static int zcache_pampd_get_data_and_free(char *data, size_t *bufsize, bool raw, |
| 1859 | void *pampd, struct tmem_pool *pool, |
| 1860 | struct tmem_oid *oid, uint32_t index) |
| 1861 | { |
| 1862 | int ret = 0; |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1863 | unsigned long flags; |
| 1864 | struct zcache_client *cli = pool->client; |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1865 | |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1866 | BUG_ON(preemptible()); |
| 1867 | BUG_ON(pampd_is_remote(pampd)); |
| 1868 | if (is_ephemeral(pool)) { |
| 1869 | local_irq_save(flags); |
| 1870 | if (raw) |
| 1871 | zbud_copy_from_pampd(data, bufsize, pampd); |
| 1872 | else |
| 1873 | ret = zbud_decompress(virt_to_page(data), pampd); |
| 1874 | zbud_free_and_delist((struct zbud_hdr *)pampd); |
| 1875 | local_irq_restore(flags); |
| 1876 | if (!is_local_client(cli)) |
| 1877 | dec_and_check(&ramster_foreign_eph_pampd_count); |
| 1878 | dec_and_check(&zcache_curr_eph_pampd_count); |
| 1879 | } else { |
| 1880 | if (is_local_client(cli)) |
| 1881 | BUG(); |
| 1882 | if (raw) |
| 1883 | zv_copy_from_pampd(data, bufsize, pampd); |
| 1884 | else |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 1885 | zv_decompress(virt_to_page(data), pampd); |
| 1886 | zv_free(cli->xvpool, pampd); |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1887 | if (!is_local_client(cli)) |
| 1888 | dec_and_check(&ramster_foreign_pers_pampd_count); |
| 1889 | dec_and_check(&zcache_curr_pers_pampd_count); |
| 1890 | ret = 0; |
| 1891 | } |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1892 | return ret; |
| 1893 | } |
| 1894 | |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1895 | static bool zcache_pampd_is_remote(void *pampd) |
| 1896 | { |
| 1897 | return pampd_is_remote(pampd); |
| 1898 | } |
| 1899 | |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1900 | /* |
| 1901 | * free the pampd and remove it from any zcache lists |
| 1902 | * pampd must no longer be pointed to from any tmem data structures! |
| 1903 | */ |
| 1904 | static void zcache_pampd_free(void *pampd, struct tmem_pool *pool, |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1905 | struct tmem_oid *oid, uint32_t index, bool acct) |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1906 | { |
| 1907 | struct zcache_client *cli = pool->client; |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1908 | bool eph = is_ephemeral(pool); |
| 1909 | struct zv_hdr *zv; |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1910 | |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1911 | BUG_ON(preemptible()); |
| 1912 | if (pampd_is_remote(pampd)) { |
| 1913 | WARN_ON(acct == false); |
| 1914 | if (oid == NULL) { |
| 1915 | /* |
| 1916 | * a NULL oid means to ignore this pampd free |
| 1917 | * as the remote freeing will be handled elsewhere |
| 1918 | */ |
| 1919 | } else if (eph) { |
| 1920 | /* FIXME remote flush optional but probably good idea */ |
| 1921 | /* FIXME get these working properly again */ |
| 1922 | dec_and_check(&zcache_curr_eph_pampd_count); |
| 1923 | } else if (pampd_is_intransit(pampd)) { |
| 1924 | /* did a pers remote get_and_free, so just free local */ |
| 1925 | pampd = pampd_mask_intransit_and_remote(pampd); |
| 1926 | goto local_pers; |
| 1927 | } else { |
| 1928 | struct flushlist_node *flnode = |
| 1929 | ramster_flnode_alloc(pool); |
| 1930 | |
| 1931 | flnode->xh.client_id = pampd_remote_node(pampd); |
| 1932 | flnode->xh.pool_id = pool->pool_id; |
| 1933 | flnode->xh.oid = *oid; |
| 1934 | flnode->xh.index = index; |
| 1935 | flnode->rem_op.op = RAMSTER_REMOTIFY_FLUSH_PAGE; |
| 1936 | spin_lock(&zcache_rem_op_list_lock); |
| 1937 | list_add(&flnode->rem_op.list, &zcache_rem_op_list); |
| 1938 | spin_unlock(&zcache_rem_op_list_lock); |
| 1939 | dec_and_check(&zcache_curr_pers_pampd_count); |
| 1940 | dec_and_check(&ramster_remote_pers_pages); |
| 1941 | } |
| 1942 | } else if (eph) { |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1943 | zbud_free_and_delist((struct zbud_hdr *)pampd); |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1944 | if (!is_local_client(pool->client)) |
| 1945 | dec_and_check(&ramster_foreign_eph_pampd_count); |
| 1946 | if (acct) |
| 1947 | /* FIXME get these working properly again */ |
| 1948 | dec_and_check(&zcache_curr_eph_pampd_count); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1949 | } else { |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1950 | local_pers: |
| 1951 | zv = (struct zv_hdr *)pampd; |
| 1952 | if (!is_local_client(pool->client)) |
| 1953 | dec_and_check(&ramster_foreign_pers_pampd_count); |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 1954 | zv_free(cli->xvpool, zv); |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1955 | if (acct) |
| 1956 | /* FIXME get these working properly again */ |
| 1957 | dec_and_check(&zcache_curr_pers_pampd_count); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1958 | } |
| 1959 | } |
| 1960 | |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1961 | static void zcache_pampd_free_obj(struct tmem_pool *pool, |
| 1962 | struct tmem_obj *obj) |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1963 | { |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1964 | struct flushlist_node *flnode; |
| 1965 | |
| 1966 | BUG_ON(preemptible()); |
| 1967 | if (obj->extra == NULL) |
| 1968 | return; |
| 1969 | BUG_ON(!pampd_is_remote(obj->extra)); |
| 1970 | flnode = ramster_flnode_alloc(pool); |
| 1971 | flnode->xh.client_id = pampd_remote_node(obj->extra); |
| 1972 | flnode->xh.pool_id = pool->pool_id; |
| 1973 | flnode->xh.oid = obj->oid; |
| 1974 | flnode->xh.index = FLUSH_ENTIRE_OBJECT; |
| 1975 | flnode->rem_op.op = RAMSTER_REMOTIFY_FLUSH_OBJ; |
| 1976 | spin_lock(&zcache_rem_op_list_lock); |
| 1977 | list_add(&flnode->rem_op.list, &zcache_rem_op_list); |
| 1978 | spin_unlock(&zcache_rem_op_list_lock); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1979 | } |
| 1980 | |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1981 | void zcache_pampd_new_obj(struct tmem_obj *obj) |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1982 | { |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1983 | obj->extra = NULL; |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1984 | } |
| 1985 | |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1986 | int zcache_pampd_replace_in_obj(void *new_pampd, struct tmem_obj *obj) |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 1987 | { |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 1988 | int ret = -1; |
| 1989 | |
| 1990 | if (new_pampd != NULL) { |
| 1991 | if (obj->extra == NULL) |
| 1992 | obj->extra = new_pampd; |
| 1993 | /* enforce that all remote pages in an object reside |
| 1994 | * in the same node! */ |
| 1995 | else if (pampd_remote_node(new_pampd) != |
| 1996 | pampd_remote_node((void *)(obj->extra))) |
| 1997 | BUG(); |
| 1998 | ret = 0; |
| 1999 | } |
| 2000 | return ret; |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 2001 | } |
| 2002 | |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 2003 | /* |
| 2004 | * Called by the message handler after a (still compressed) page has been |
| 2005 | * fetched from the remote machine in response to an "is_remote" tmem_get |
| 2006 | * or persistent tmem_localify. For a tmem_get, "extra" is the address of |
Masanari Iida | 01fdf90 | 2012-05-08 00:26:07 +0900 | [diff] [blame] | 2007 | * the page that is to be filled to successfully resolve the tmem_get; for |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 2008 | * a (persistent) tmem_localify, "extra" is NULL (as the data is placed only |
| 2009 | * in the local zcache). "data" points to "size" bytes of (compressed) data |
| 2010 | * passed in the message. In the case of a persistent remote get, if |
| 2011 | * pre-allocation was successful (see zcache_repatriate_preload), the page |
| 2012 | * is placed into both local zcache and at "extra". |
| 2013 | */ |
| 2014 | int zcache_localify(int pool_id, struct tmem_oid *oidp, |
| 2015 | uint32_t index, char *data, size_t size, |
| 2016 | void *extra) |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 2017 | { |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 2018 | int ret = -ENOENT; |
| 2019 | unsigned long flags; |
| 2020 | struct tmem_pool *pool; |
| 2021 | bool ephemeral, delete = false; |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 2022 | size_t clen = PAGE_SIZE; |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 2023 | void *pampd, *saved_hb; |
| 2024 | struct tmem_obj *obj; |
| 2025 | |
| 2026 | pool = zcache_get_pool_by_id(LOCAL_CLIENT, pool_id); |
| 2027 | if (unlikely(pool == NULL)) |
| 2028 | /* pool doesn't exist anymore */ |
| 2029 | goto out; |
| 2030 | ephemeral = is_ephemeral(pool); |
| 2031 | local_irq_save(flags); /* FIXME: maybe only disable softirqs? */ |
| 2032 | pampd = tmem_localify_get_pampd(pool, oidp, index, &obj, &saved_hb); |
| 2033 | if (pampd == NULL) { |
| 2034 | /* hmmm... must have been a flush while waiting */ |
| 2035 | #ifdef RAMSTER_TESTING |
| 2036 | pr_err("UNTESTED pampd==NULL in zcache_localify\n"); |
| 2037 | #endif |
| 2038 | if (ephemeral) |
| 2039 | ramster_remote_eph_pages_unsucc_get++; |
| 2040 | else |
| 2041 | ramster_remote_pers_pages_unsucc_get++; |
| 2042 | obj = NULL; |
| 2043 | goto finish; |
| 2044 | } else if (unlikely(!pampd_is_remote(pampd))) { |
| 2045 | /* hmmm... must have been a dup put while waiting */ |
| 2046 | #ifdef RAMSTER_TESTING |
| 2047 | pr_err("UNTESTED dup while waiting in zcache_localify\n"); |
| 2048 | #endif |
| 2049 | if (ephemeral) |
| 2050 | ramster_remote_eph_pages_unsucc_get++; |
| 2051 | else |
| 2052 | ramster_remote_pers_pages_unsucc_get++; |
| 2053 | obj = NULL; |
| 2054 | pampd = NULL; |
| 2055 | ret = -EEXIST; |
| 2056 | goto finish; |
| 2057 | } else if (size == 0) { |
| 2058 | /* no remote data, delete the local is_remote pampd */ |
| 2059 | pampd = NULL; |
| 2060 | if (ephemeral) |
| 2061 | ramster_remote_eph_pages_unsucc_get++; |
| 2062 | else |
| 2063 | BUG(); |
| 2064 | delete = true; |
| 2065 | goto finish; |
| 2066 | } |
| 2067 | if (!ephemeral && pampd_is_intransit(pampd)) { |
| 2068 | /* localify to zcache */ |
| 2069 | pampd = pampd_mask_intransit_and_remote(pampd); |
| 2070 | zv_copy_to_pampd(pampd, data, size); |
| 2071 | } else { |
| 2072 | pampd = NULL; |
| 2073 | obj = NULL; |
| 2074 | } |
| 2075 | if (extra != NULL) { |
| 2076 | /* decompress direct-to-memory to complete remotify */ |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 2077 | ret = lzo1x_decompress_safe((char *)data, size, |
| 2078 | (char *)extra, &clen); |
| 2079 | BUG_ON(ret != LZO_E_OK); |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 2080 | BUG_ON(clen != PAGE_SIZE); |
| 2081 | } |
| 2082 | if (ephemeral) |
| 2083 | ramster_remote_eph_pages_succ_get++; |
| 2084 | else |
| 2085 | ramster_remote_pers_pages_succ_get++; |
| 2086 | ret = 0; |
| 2087 | finish: |
| 2088 | tmem_localify_finish(obj, index, pampd, saved_hb, delete); |
| 2089 | zcache_put_pool(pool); |
| 2090 | local_irq_restore(flags); |
| 2091 | out: |
| 2092 | return ret; |
| 2093 | } |
| 2094 | |
| 2095 | /* |
| 2096 | * Called on a remote persistent tmem_get to attempt to preallocate |
| 2097 | * local storage for the data contained in the remote persistent page. |
Justin P. Mattock | d740e88 | 2012-04-09 07:48:57 -0700 | [diff] [blame] | 2098 | * If successfully preallocated, returns the pampd, marked as remote and |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 2099 | * in_transit. Else returns NULL. Note that the appropriate tmem data |
| 2100 | * structure must be locked. |
| 2101 | */ |
| 2102 | static void *zcache_pampd_repatriate_preload(void *pampd, |
| 2103 | struct tmem_pool *pool, |
| 2104 | struct tmem_oid *oid, |
| 2105 | uint32_t index, |
| 2106 | bool *intransit) |
| 2107 | { |
| 2108 | int clen = pampd_remote_size(pampd); |
| 2109 | void *ret_pampd = NULL; |
| 2110 | unsigned long flags; |
| 2111 | |
| 2112 | if (!pampd_is_remote(pampd)) |
| 2113 | BUG(); |
| 2114 | if (is_ephemeral(pool)) |
| 2115 | BUG(); |
| 2116 | if (pampd_is_intransit(pampd)) { |
| 2117 | /* |
| 2118 | * to avoid multiple allocations (and maybe a memory leak) |
| 2119 | * don't preallocate if already in the process of being |
| 2120 | * repatriated |
| 2121 | */ |
| 2122 | *intransit = true; |
| 2123 | goto out; |
| 2124 | } |
| 2125 | *intransit = false; |
| 2126 | local_irq_save(flags); |
| 2127 | ret_pampd = (void *)zv_alloc(pool, oid, index, clen); |
| 2128 | if (ret_pampd != NULL) { |
| 2129 | /* |
| 2130 | * a pampd is marked intransit if it is remote and space has |
| 2131 | * been allocated for it locally (note, only happens for |
| 2132 | * persistent pages, in which case the remote copy is freed) |
| 2133 | */ |
| 2134 | ret_pampd = pampd_mark_intransit(ret_pampd); |
| 2135 | dec_and_check(&ramster_remote_pers_pages); |
| 2136 | } else |
| 2137 | ramster_pers_pages_remote_nomem++; |
| 2138 | local_irq_restore(flags); |
| 2139 | out: |
| 2140 | return ret_pampd; |
| 2141 | } |
| 2142 | |
| 2143 | /* |
| 2144 | * Called on a remote tmem_get to invoke a message to fetch the page. |
| 2145 | * Might sleep so no tmem locks can be held. "extra" is passed |
| 2146 | * all the way through the round-trip messaging to zcache_localify. |
| 2147 | */ |
| 2148 | static int zcache_pampd_repatriate(void *fake_pampd, void *real_pampd, |
| 2149 | struct tmem_pool *pool, |
| 2150 | struct tmem_oid *oid, uint32_t index, |
| 2151 | bool free, void *extra) |
| 2152 | { |
| 2153 | struct tmem_xhandle xh; |
| 2154 | int ret; |
| 2155 | |
| 2156 | if (pampd_is_intransit(real_pampd)) |
| 2157 | /* have local space pre-reserved, so free remote copy */ |
| 2158 | free = true; |
| 2159 | xh = tmem_xhandle_fill(LOCAL_CLIENT, pool, oid, index); |
| 2160 | /* unreliable request/response for now */ |
| 2161 | ret = ramster_remote_async_get(&xh, free, |
| 2162 | pampd_remote_node(fake_pampd), |
| 2163 | pampd_remote_size(fake_pampd), |
| 2164 | pampd_remote_cksum(fake_pampd), |
| 2165 | extra); |
| 2166 | #ifdef RAMSTER_TESTING |
| 2167 | if (ret != 0 && ret != -ENOENT) |
| 2168 | pr_err("TESTING zcache_pampd_repatriate returns, ret=%d\n", |
| 2169 | ret); |
| 2170 | #endif |
| 2171 | return ret; |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 2172 | } |
| 2173 | |
| 2174 | static struct tmem_pamops zcache_pamops = { |
| 2175 | .create = zcache_pampd_create, |
| 2176 | .get_data = zcache_pampd_get_data, |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 2177 | .free = zcache_pampd_free, |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 2178 | .get_data_and_free = zcache_pampd_get_data_and_free, |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 2179 | .free_obj = zcache_pampd_free_obj, |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 2180 | .is_remote = zcache_pampd_is_remote, |
| 2181 | .repatriate_preload = zcache_pampd_repatriate_preload, |
| 2182 | .repatriate = zcache_pampd_repatriate, |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 2183 | .new_obj = zcache_pampd_new_obj, |
| 2184 | .replace_in_obj = zcache_pampd_replace_in_obj, |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 2185 | }; |
| 2186 | |
| 2187 | /* |
| 2188 | * zcache compression/decompression and related per-cpu stuff |
| 2189 | */ |
| 2190 | |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 2191 | #define LZO_WORKMEM_BYTES LZO1X_1_MEM_COMPRESS |
| 2192 | #define LZO_DSTMEM_PAGE_ORDER 1 |
| 2193 | static DEFINE_PER_CPU(unsigned char *, zcache_workmem); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 2194 | static DEFINE_PER_CPU(unsigned char *, zcache_dstmem); |
| 2195 | |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 2196 | static int zcache_compress(struct page *from, void **out_va, size_t *out_len) |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 2197 | { |
| 2198 | int ret = 0; |
| 2199 | unsigned char *dmem = __get_cpu_var(zcache_dstmem); |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 2200 | unsigned char *wmem = __get_cpu_var(zcache_workmem); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 2201 | char *from_va; |
| 2202 | |
| 2203 | BUG_ON(!irqs_disabled()); |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 2204 | if (unlikely(dmem == NULL || wmem == NULL)) |
| 2205 | goto out; /* no buffer, so can't compress */ |
Linus Torvalds | 9f39383 | 2012-03-21 09:40:26 -0700 | [diff] [blame] | 2206 | from_va = kmap_atomic(from); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 2207 | mb(); |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 2208 | ret = lzo1x_1_compress(from_va, PAGE_SIZE, dmem, out_len, wmem); |
| 2209 | BUG_ON(ret != LZO_E_OK); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 2210 | *out_va = dmem; |
Linus Torvalds | 9f39383 | 2012-03-21 09:40:26 -0700 | [diff] [blame] | 2211 | kunmap_atomic(from_va); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 2212 | ret = 1; |
| 2213 | out: |
| 2214 | return ret; |
| 2215 | } |
| 2216 | |
| 2217 | |
| 2218 | static int zcache_cpu_notifier(struct notifier_block *nb, |
| 2219 | unsigned long action, void *pcpu) |
| 2220 | { |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 2221 | int cpu = (long)pcpu; |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 2222 | struct zcache_preload *kp; |
| 2223 | |
| 2224 | switch (action) { |
| 2225 | case CPU_UP_PREPARE: |
| 2226 | per_cpu(zcache_dstmem, cpu) = (void *)__get_free_pages( |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 2227 | GFP_KERNEL | __GFP_REPEAT, |
| 2228 | LZO_DSTMEM_PAGE_ORDER), |
| 2229 | per_cpu(zcache_workmem, cpu) = |
| 2230 | kzalloc(LZO1X_MEM_COMPRESS, |
| 2231 | GFP_KERNEL | __GFP_REPEAT); |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 2232 | per_cpu(zcache_remoteputmem, cpu) = |
| 2233 | kzalloc(PAGE_SIZE, GFP_KERNEL | __GFP_REPEAT); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 2234 | break; |
| 2235 | case CPU_DEAD: |
| 2236 | case CPU_UP_CANCELED: |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 2237 | kfree(per_cpu(zcache_remoteputmem, cpu)); |
| 2238 | per_cpu(zcache_remoteputmem, cpu) = NULL; |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 2239 | free_pages((unsigned long)per_cpu(zcache_dstmem, cpu), |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 2240 | LZO_DSTMEM_PAGE_ORDER); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 2241 | per_cpu(zcache_dstmem, cpu) = NULL; |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 2242 | kfree(per_cpu(zcache_workmem, cpu)); |
| 2243 | per_cpu(zcache_workmem, cpu) = NULL; |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 2244 | kp = &per_cpu(zcache_preloads, cpu); |
| 2245 | while (kp->nr) { |
| 2246 | kmem_cache_free(zcache_objnode_cache, |
| 2247 | kp->objnodes[kp->nr - 1]); |
| 2248 | kp->objnodes[kp->nr - 1] = NULL; |
| 2249 | kp->nr--; |
| 2250 | } |
| 2251 | if (kp->obj) { |
| 2252 | kmem_cache_free(zcache_obj_cache, kp->obj); |
| 2253 | kp->obj = NULL; |
| 2254 | } |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 2255 | if (kp->flnode) { |
| 2256 | kmem_cache_free(ramster_flnode_cache, kp->flnode); |
| 2257 | kp->flnode = NULL; |
| 2258 | } |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 2259 | if (kp->page) { |
| 2260 | free_page((unsigned long)kp->page); |
| 2261 | kp->page = NULL; |
| 2262 | } |
| 2263 | break; |
| 2264 | default: |
| 2265 | break; |
| 2266 | } |
| 2267 | return NOTIFY_OK; |
| 2268 | } |
| 2269 | |
| 2270 | static struct notifier_block zcache_cpu_notifier_block = { |
| 2271 | .notifier_call = zcache_cpu_notifier |
| 2272 | }; |
| 2273 | |
| 2274 | #ifdef CONFIG_SYSFS |
| 2275 | #define ZCACHE_SYSFS_RO(_name) \ |
| 2276 | static ssize_t zcache_##_name##_show(struct kobject *kobj, \ |
| 2277 | struct kobj_attribute *attr, char *buf) \ |
| 2278 | { \ |
| 2279 | return sprintf(buf, "%lu\n", zcache_##_name); \ |
| 2280 | } \ |
| 2281 | static struct kobj_attribute zcache_##_name##_attr = { \ |
| 2282 | .attr = { .name = __stringify(_name), .mode = 0444 }, \ |
| 2283 | .show = zcache_##_name##_show, \ |
| 2284 | } |
| 2285 | |
| 2286 | #define ZCACHE_SYSFS_RO_ATOMIC(_name) \ |
| 2287 | static ssize_t zcache_##_name##_show(struct kobject *kobj, \ |
| 2288 | struct kobj_attribute *attr, char *buf) \ |
| 2289 | { \ |
| 2290 | return sprintf(buf, "%d\n", atomic_read(&zcache_##_name)); \ |
| 2291 | } \ |
| 2292 | static struct kobj_attribute zcache_##_name##_attr = { \ |
| 2293 | .attr = { .name = __stringify(_name), .mode = 0444 }, \ |
| 2294 | .show = zcache_##_name##_show, \ |
| 2295 | } |
| 2296 | |
| 2297 | #define ZCACHE_SYSFS_RO_CUSTOM(_name, _func) \ |
| 2298 | static ssize_t zcache_##_name##_show(struct kobject *kobj, \ |
| 2299 | struct kobj_attribute *attr, char *buf) \ |
| 2300 | { \ |
| 2301 | return _func(buf); \ |
| 2302 | } \ |
| 2303 | static struct kobj_attribute zcache_##_name##_attr = { \ |
| 2304 | .attr = { .name = __stringify(_name), .mode = 0444 }, \ |
| 2305 | .show = zcache_##_name##_show, \ |
| 2306 | } |
| 2307 | |
| 2308 | ZCACHE_SYSFS_RO(curr_obj_count_max); |
| 2309 | ZCACHE_SYSFS_RO(curr_objnode_count_max); |
| 2310 | ZCACHE_SYSFS_RO(flush_total); |
| 2311 | ZCACHE_SYSFS_RO(flush_found); |
| 2312 | ZCACHE_SYSFS_RO(flobj_total); |
| 2313 | ZCACHE_SYSFS_RO(flobj_found); |
| 2314 | ZCACHE_SYSFS_RO(failed_eph_puts); |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 2315 | ZCACHE_SYSFS_RO(nonactive_puts); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 2316 | ZCACHE_SYSFS_RO(failed_pers_puts); |
| 2317 | ZCACHE_SYSFS_RO(zbud_curr_zbytes); |
| 2318 | ZCACHE_SYSFS_RO(zbud_cumul_zpages); |
| 2319 | ZCACHE_SYSFS_RO(zbud_cumul_zbytes); |
| 2320 | ZCACHE_SYSFS_RO(zbud_buddied_count); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 2321 | ZCACHE_SYSFS_RO(evicted_raw_pages); |
| 2322 | ZCACHE_SYSFS_RO(evicted_unbuddied_pages); |
| 2323 | ZCACHE_SYSFS_RO(evicted_buddied_pages); |
| 2324 | ZCACHE_SYSFS_RO(failed_get_free_pages); |
| 2325 | ZCACHE_SYSFS_RO(failed_alloc); |
| 2326 | ZCACHE_SYSFS_RO(put_to_flush); |
| 2327 | ZCACHE_SYSFS_RO(compress_poor); |
| 2328 | ZCACHE_SYSFS_RO(mean_compress_poor); |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 2329 | ZCACHE_SYSFS_RO(policy_percent_exceeded); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 2330 | ZCACHE_SYSFS_RO_ATOMIC(zbud_curr_raw_pages); |
| 2331 | ZCACHE_SYSFS_RO_ATOMIC(zbud_curr_zpages); |
| 2332 | ZCACHE_SYSFS_RO_ATOMIC(curr_obj_count); |
| 2333 | ZCACHE_SYSFS_RO_ATOMIC(curr_objnode_count); |
| 2334 | ZCACHE_SYSFS_RO_CUSTOM(zbud_unbuddied_list_counts, |
| 2335 | zbud_show_unbuddied_list_counts); |
| 2336 | ZCACHE_SYSFS_RO_CUSTOM(zbud_cumul_chunk_counts, |
| 2337 | zbud_show_cumul_chunk_counts); |
| 2338 | ZCACHE_SYSFS_RO_CUSTOM(zv_curr_dist_counts, |
| 2339 | zv_curr_dist_counts_show); |
| 2340 | ZCACHE_SYSFS_RO_CUSTOM(zv_cumul_dist_counts, |
| 2341 | zv_cumul_dist_counts_show); |
| 2342 | |
| 2343 | static struct attribute *zcache_attrs[] = { |
| 2344 | &zcache_curr_obj_count_attr.attr, |
| 2345 | &zcache_curr_obj_count_max_attr.attr, |
| 2346 | &zcache_curr_objnode_count_attr.attr, |
| 2347 | &zcache_curr_objnode_count_max_attr.attr, |
| 2348 | &zcache_flush_total_attr.attr, |
| 2349 | &zcache_flobj_total_attr.attr, |
| 2350 | &zcache_flush_found_attr.attr, |
| 2351 | &zcache_flobj_found_attr.attr, |
| 2352 | &zcache_failed_eph_puts_attr.attr, |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 2353 | &zcache_nonactive_puts_attr.attr, |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 2354 | &zcache_failed_pers_puts_attr.attr, |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 2355 | &zcache_policy_percent_exceeded_attr.attr, |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 2356 | &zcache_compress_poor_attr.attr, |
| 2357 | &zcache_mean_compress_poor_attr.attr, |
| 2358 | &zcache_zbud_curr_raw_pages_attr.attr, |
| 2359 | &zcache_zbud_curr_zpages_attr.attr, |
| 2360 | &zcache_zbud_curr_zbytes_attr.attr, |
| 2361 | &zcache_zbud_cumul_zpages_attr.attr, |
| 2362 | &zcache_zbud_cumul_zbytes_attr.attr, |
| 2363 | &zcache_zbud_buddied_count_attr.attr, |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 2364 | &zcache_evicted_raw_pages_attr.attr, |
| 2365 | &zcache_evicted_unbuddied_pages_attr.attr, |
| 2366 | &zcache_evicted_buddied_pages_attr.attr, |
| 2367 | &zcache_failed_get_free_pages_attr.attr, |
| 2368 | &zcache_failed_alloc_attr.attr, |
| 2369 | &zcache_put_to_flush_attr.attr, |
| 2370 | &zcache_zbud_unbuddied_list_counts_attr.attr, |
| 2371 | &zcache_zbud_cumul_chunk_counts_attr.attr, |
| 2372 | &zcache_zv_curr_dist_counts_attr.attr, |
| 2373 | &zcache_zv_cumul_dist_counts_attr.attr, |
| 2374 | &zcache_zv_max_zsize_attr.attr, |
| 2375 | &zcache_zv_max_mean_zsize_attr.attr, |
| 2376 | &zcache_zv_page_count_policy_percent_attr.attr, |
| 2377 | NULL, |
| 2378 | }; |
| 2379 | |
| 2380 | static struct attribute_group zcache_attr_group = { |
| 2381 | .attrs = zcache_attrs, |
| 2382 | .name = "zcache", |
| 2383 | }; |
| 2384 | |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 2385 | #define RAMSTER_SYSFS_RO(_name) \ |
| 2386 | static ssize_t ramster_##_name##_show(struct kobject *kobj, \ |
| 2387 | struct kobj_attribute *attr, char *buf) \ |
| 2388 | { \ |
| 2389 | return sprintf(buf, "%lu\n", ramster_##_name); \ |
| 2390 | } \ |
| 2391 | static struct kobj_attribute ramster_##_name##_attr = { \ |
| 2392 | .attr = { .name = __stringify(_name), .mode = 0444 }, \ |
| 2393 | .show = ramster_##_name##_show, \ |
| 2394 | } |
| 2395 | |
| 2396 | #define RAMSTER_SYSFS_RW(_name) \ |
| 2397 | static ssize_t ramster_##_name##_show(struct kobject *kobj, \ |
| 2398 | struct kobj_attribute *attr, char *buf) \ |
| 2399 | { \ |
| 2400 | return sprintf(buf, "%lu\n", ramster_##_name); \ |
| 2401 | } \ |
| 2402 | static ssize_t ramster_##_name##_store(struct kobject *kobj, \ |
| 2403 | struct kobj_attribute *attr, const char *buf, size_t count) \ |
| 2404 | { \ |
| 2405 | int err; \ |
| 2406 | unsigned long enable; \ |
| 2407 | err = kstrtoul(buf, 10, &enable); \ |
| 2408 | if (err) \ |
| 2409 | return -EINVAL; \ |
| 2410 | ramster_##_name = enable; \ |
| 2411 | return count; \ |
| 2412 | } \ |
| 2413 | static struct kobj_attribute ramster_##_name##_attr = { \ |
| 2414 | .attr = { .name = __stringify(_name), .mode = 0644 }, \ |
| 2415 | .show = ramster_##_name##_show, \ |
| 2416 | .store = ramster_##_name##_store, \ |
| 2417 | } |
| 2418 | |
| 2419 | #define RAMSTER_SYSFS_RO_ATOMIC(_name) \ |
| 2420 | static ssize_t ramster_##_name##_show(struct kobject *kobj, \ |
| 2421 | struct kobj_attribute *attr, char *buf) \ |
| 2422 | { \ |
| 2423 | return sprintf(buf, "%d\n", atomic_read(&ramster_##_name)); \ |
| 2424 | } \ |
| 2425 | static struct kobj_attribute ramster_##_name##_attr = { \ |
| 2426 | .attr = { .name = __stringify(_name), .mode = 0444 }, \ |
| 2427 | .show = ramster_##_name##_show, \ |
| 2428 | } |
| 2429 | |
| 2430 | RAMSTER_SYSFS_RO(interface_revision); |
| 2431 | RAMSTER_SYSFS_RO_ATOMIC(remote_pers_pages); |
| 2432 | RAMSTER_SYSFS_RW(pers_remotify_enable); |
| 2433 | RAMSTER_SYSFS_RW(eph_remotify_enable); |
| 2434 | RAMSTER_SYSFS_RO(eph_pages_remoted); |
| 2435 | RAMSTER_SYSFS_RO(eph_pages_remote_failed); |
| 2436 | RAMSTER_SYSFS_RO(pers_pages_remoted); |
| 2437 | RAMSTER_SYSFS_RO(pers_pages_remote_failed); |
| 2438 | RAMSTER_SYSFS_RO(pers_pages_remote_nomem); |
| 2439 | RAMSTER_SYSFS_RO(remote_pages_flushed); |
| 2440 | RAMSTER_SYSFS_RO(remote_page_flushes_failed); |
| 2441 | RAMSTER_SYSFS_RO(remote_objects_flushed); |
| 2442 | RAMSTER_SYSFS_RO(remote_object_flushes_failed); |
| 2443 | RAMSTER_SYSFS_RO(remote_eph_pages_succ_get); |
| 2444 | RAMSTER_SYSFS_RO(remote_eph_pages_unsucc_get); |
| 2445 | RAMSTER_SYSFS_RO(remote_pers_pages_succ_get); |
| 2446 | RAMSTER_SYSFS_RO(remote_pers_pages_unsucc_get); |
| 2447 | RAMSTER_SYSFS_RO_ATOMIC(foreign_eph_pampd_count); |
| 2448 | RAMSTER_SYSFS_RO(foreign_eph_pampd_count_max); |
| 2449 | RAMSTER_SYSFS_RO_ATOMIC(foreign_pers_pampd_count); |
| 2450 | RAMSTER_SYSFS_RO(foreign_pers_pampd_count_max); |
| 2451 | RAMSTER_SYSFS_RO_ATOMIC(curr_flnode_count); |
| 2452 | RAMSTER_SYSFS_RO(curr_flnode_count_max); |
| 2453 | |
| 2454 | #define MANUAL_NODES 8 |
| 2455 | static bool ramster_nodes_manual_up[MANUAL_NODES]; |
| 2456 | static ssize_t ramster_manual_node_up_show(struct kobject *kobj, |
| 2457 | struct kobj_attribute *attr, char *buf) |
| 2458 | { |
| 2459 | int i; |
| 2460 | char *p = buf; |
| 2461 | for (i = 0; i < MANUAL_NODES; i++) |
| 2462 | if (ramster_nodes_manual_up[i]) |
| 2463 | p += sprintf(p, "%d ", i); |
| 2464 | p += sprintf(p, "\n"); |
| 2465 | return p - buf; |
| 2466 | } |
| 2467 | |
| 2468 | static ssize_t ramster_manual_node_up_store(struct kobject *kobj, |
| 2469 | struct kobj_attribute *attr, const char *buf, size_t count) |
| 2470 | { |
| 2471 | int err; |
| 2472 | unsigned long node_num; |
| 2473 | |
| 2474 | err = kstrtoul(buf, 10, &node_num); |
| 2475 | if (err) { |
| 2476 | pr_err("ramster: bad strtoul?\n"); |
| 2477 | return -EINVAL; |
| 2478 | } |
| 2479 | if (node_num >= MANUAL_NODES) { |
| 2480 | pr_err("ramster: bad node_num=%lu?\n", node_num); |
| 2481 | return -EINVAL; |
| 2482 | } |
| 2483 | if (ramster_nodes_manual_up[node_num]) { |
| 2484 | pr_err("ramster: node %d already up, ignoring\n", |
| 2485 | (int)node_num); |
| 2486 | } else { |
| 2487 | ramster_nodes_manual_up[node_num] = true; |
| 2488 | r2net_hb_node_up_manual((int)node_num); |
| 2489 | } |
| 2490 | return count; |
| 2491 | } |
| 2492 | |
| 2493 | static struct kobj_attribute ramster_manual_node_up_attr = { |
| 2494 | .attr = { .name = "manual_node_up", .mode = 0644 }, |
| 2495 | .show = ramster_manual_node_up_show, |
| 2496 | .store = ramster_manual_node_up_store, |
| 2497 | }; |
| 2498 | |
| 2499 | static ssize_t ramster_remote_target_nodenum_show(struct kobject *kobj, |
| 2500 | struct kobj_attribute *attr, char *buf) |
| 2501 | { |
| 2502 | if (ramster_remote_target_nodenum == -1UL) |
| 2503 | return sprintf(buf, "unset\n"); |
| 2504 | else |
| 2505 | return sprintf(buf, "%d\n", ramster_remote_target_nodenum); |
| 2506 | } |
| 2507 | |
| 2508 | static ssize_t ramster_remote_target_nodenum_store(struct kobject *kobj, |
| 2509 | struct kobj_attribute *attr, const char *buf, size_t count) |
| 2510 | { |
| 2511 | int err; |
| 2512 | unsigned long node_num; |
| 2513 | |
| 2514 | err = kstrtoul(buf, 10, &node_num); |
| 2515 | if (err) { |
| 2516 | pr_err("ramster: bad strtoul?\n"); |
| 2517 | return -EINVAL; |
| 2518 | } else if (node_num == -1UL) { |
| 2519 | pr_err("ramster: disabling all remotification, " |
| 2520 | "data may still reside on remote nodes however\n"); |
| 2521 | return -EINVAL; |
| 2522 | } else if (node_num >= MANUAL_NODES) { |
| 2523 | pr_err("ramster: bad node_num=%lu?\n", node_num); |
| 2524 | return -EINVAL; |
| 2525 | } else if (!ramster_nodes_manual_up[node_num]) { |
| 2526 | pr_err("ramster: node %d not up, ignoring setting " |
| 2527 | "of remotification target\n", (int)node_num); |
| 2528 | } else if (r2net_remote_target_node_set((int)node_num) >= 0) { |
| 2529 | pr_info("ramster: node %d set as remotification target\n", |
| 2530 | (int)node_num); |
| 2531 | ramster_remote_target_nodenum = (int)node_num; |
| 2532 | } else { |
| 2533 | pr_err("ramster: bad num to node node_num=%d?\n", |
| 2534 | (int)node_num); |
| 2535 | return -EINVAL; |
| 2536 | } |
| 2537 | return count; |
| 2538 | } |
| 2539 | |
| 2540 | static struct kobj_attribute ramster_remote_target_nodenum_attr = { |
| 2541 | .attr = { .name = "remote_target_nodenum", .mode = 0644 }, |
| 2542 | .show = ramster_remote_target_nodenum_show, |
| 2543 | .store = ramster_remote_target_nodenum_store, |
| 2544 | }; |
| 2545 | |
| 2546 | |
| 2547 | static struct attribute *ramster_attrs[] = { |
| 2548 | &ramster_interface_revision_attr.attr, |
| 2549 | &ramster_pers_remotify_enable_attr.attr, |
| 2550 | &ramster_eph_remotify_enable_attr.attr, |
| 2551 | &ramster_remote_pers_pages_attr.attr, |
| 2552 | &ramster_eph_pages_remoted_attr.attr, |
| 2553 | &ramster_eph_pages_remote_failed_attr.attr, |
| 2554 | &ramster_pers_pages_remoted_attr.attr, |
| 2555 | &ramster_pers_pages_remote_failed_attr.attr, |
| 2556 | &ramster_pers_pages_remote_nomem_attr.attr, |
| 2557 | &ramster_remote_pages_flushed_attr.attr, |
| 2558 | &ramster_remote_page_flushes_failed_attr.attr, |
| 2559 | &ramster_remote_objects_flushed_attr.attr, |
| 2560 | &ramster_remote_object_flushes_failed_attr.attr, |
| 2561 | &ramster_remote_eph_pages_succ_get_attr.attr, |
| 2562 | &ramster_remote_eph_pages_unsucc_get_attr.attr, |
| 2563 | &ramster_remote_pers_pages_succ_get_attr.attr, |
| 2564 | &ramster_remote_pers_pages_unsucc_get_attr.attr, |
| 2565 | &ramster_foreign_eph_pampd_count_attr.attr, |
| 2566 | &ramster_foreign_eph_pampd_count_max_attr.attr, |
| 2567 | &ramster_foreign_pers_pampd_count_attr.attr, |
| 2568 | &ramster_foreign_pers_pampd_count_max_attr.attr, |
| 2569 | &ramster_curr_flnode_count_attr.attr, |
| 2570 | &ramster_curr_flnode_count_max_attr.attr, |
| 2571 | &ramster_manual_node_up_attr.attr, |
| 2572 | &ramster_remote_target_nodenum_attr.attr, |
| 2573 | NULL, |
| 2574 | }; |
| 2575 | |
| 2576 | static struct attribute_group ramster_attr_group = { |
| 2577 | .attrs = ramster_attrs, |
| 2578 | .name = "ramster", |
| 2579 | }; |
| 2580 | |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 2581 | #endif /* CONFIG_SYSFS */ |
| 2582 | /* |
| 2583 | * When zcache is disabled ("frozen"), pools can be created and destroyed, |
| 2584 | * but all puts (and thus all other operations that require memory allocation) |
| 2585 | * must fail. If zcache is unfrozen, accepts puts, then frozen again, |
| 2586 | * data consistency requires all puts while frozen to be converted into |
| 2587 | * flushes. |
| 2588 | */ |
| 2589 | static bool zcache_freeze; |
| 2590 | |
| 2591 | /* |
| 2592 | * zcache shrinker interface (only useful for ephemeral pages, so zbud only) |
| 2593 | */ |
| 2594 | static int shrink_zcache_memory(struct shrinker *shrink, |
| 2595 | struct shrink_control *sc) |
| 2596 | { |
| 2597 | int ret = -1; |
| 2598 | int nr = sc->nr_to_scan; |
| 2599 | gfp_t gfp_mask = sc->gfp_mask; |
| 2600 | |
| 2601 | if (nr >= 0) { |
| 2602 | if (!(gfp_mask & __GFP_FS)) |
| 2603 | /* does this case really need to be skipped? */ |
| 2604 | goto out; |
| 2605 | zbud_evict_pages(nr); |
| 2606 | } |
| 2607 | ret = (int)atomic_read(&zcache_zbud_curr_raw_pages); |
| 2608 | out: |
| 2609 | return ret; |
| 2610 | } |
| 2611 | |
| 2612 | static struct shrinker zcache_shrinker = { |
| 2613 | .shrink = shrink_zcache_memory, |
| 2614 | .seeks = DEFAULT_SEEKS, |
| 2615 | }; |
| 2616 | |
| 2617 | /* |
| 2618 | * zcache shims between cleancache/frontswap ops and tmem |
| 2619 | */ |
| 2620 | |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 2621 | int zcache_put(int cli_id, int pool_id, struct tmem_oid *oidp, |
| 2622 | uint32_t index, char *data, size_t size, |
| 2623 | bool raw, int ephemeral) |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 2624 | { |
| 2625 | struct tmem_pool *pool; |
| 2626 | int ret = -1; |
| 2627 | |
| 2628 | BUG_ON(!irqs_disabled()); |
| 2629 | pool = zcache_get_pool_by_id(cli_id, pool_id); |
| 2630 | if (unlikely(pool == NULL)) |
| 2631 | goto out; |
| 2632 | if (!zcache_freeze && zcache_do_preload(pool) == 0) { |
| 2633 | /* preload does preempt_disable on success */ |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 2634 | ret = tmem_put(pool, oidp, index, data, size, raw, ephemeral); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 2635 | if (ret < 0) { |
| 2636 | if (is_ephemeral(pool)) |
| 2637 | zcache_failed_eph_puts++; |
| 2638 | else |
| 2639 | zcache_failed_pers_puts++; |
| 2640 | } |
| 2641 | zcache_put_pool(pool); |
| 2642 | preempt_enable_no_resched(); |
| 2643 | } else { |
| 2644 | zcache_put_to_flush++; |
| 2645 | if (atomic_read(&pool->obj_count) > 0) |
| 2646 | /* the put fails whether the flush succeeds or not */ |
| 2647 | (void)tmem_flush_page(pool, oidp, index); |
| 2648 | zcache_put_pool(pool); |
| 2649 | } |
| 2650 | out: |
| 2651 | return ret; |
| 2652 | } |
| 2653 | |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 2654 | int zcache_get(int cli_id, int pool_id, struct tmem_oid *oidp, |
| 2655 | uint32_t index, char *data, size_t *sizep, |
| 2656 | bool raw, int get_and_free) |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 2657 | { |
| 2658 | struct tmem_pool *pool; |
| 2659 | int ret = -1; |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 2660 | bool eph; |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 2661 | |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 2662 | if (!raw) { |
| 2663 | BUG_ON(irqs_disabled()); |
| 2664 | BUG_ON(in_softirq()); |
| 2665 | } |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 2666 | pool = zcache_get_pool_by_id(cli_id, pool_id); |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 2667 | eph = is_ephemeral(pool); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 2668 | if (likely(pool != NULL)) { |
| 2669 | if (atomic_read(&pool->obj_count) > 0) |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 2670 | ret = tmem_get(pool, oidp, index, data, sizep, |
| 2671 | raw, get_and_free); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 2672 | zcache_put_pool(pool); |
| 2673 | } |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 2674 | WARN_ONCE((!eph && (ret != 0)), "zcache_get fails on persistent pool, " |
| 2675 | "bad things are very likely to happen soon\n"); |
| 2676 | #ifdef RAMSTER_TESTING |
| 2677 | if (ret != 0 && ret != -1 && !(ret == -EINVAL && is_ephemeral(pool))) |
| 2678 | pr_err("TESTING zcache_get tmem_get returns ret=%d\n", ret); |
| 2679 | #endif |
| 2680 | if (ret == -EAGAIN) |
| 2681 | BUG(); /* FIXME... don't need this anymore??? let's ensure */ |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 2682 | return ret; |
| 2683 | } |
| 2684 | |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 2685 | int zcache_flush(int cli_id, int pool_id, |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 2686 | struct tmem_oid *oidp, uint32_t index) |
| 2687 | { |
| 2688 | struct tmem_pool *pool; |
| 2689 | int ret = -1; |
| 2690 | unsigned long flags; |
| 2691 | |
| 2692 | local_irq_save(flags); |
| 2693 | zcache_flush_total++; |
| 2694 | pool = zcache_get_pool_by_id(cli_id, pool_id); |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 2695 | ramster_do_preload_flnode_only(pool); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 2696 | if (likely(pool != NULL)) { |
| 2697 | if (atomic_read(&pool->obj_count) > 0) |
| 2698 | ret = tmem_flush_page(pool, oidp, index); |
| 2699 | zcache_put_pool(pool); |
| 2700 | } |
| 2701 | if (ret >= 0) |
| 2702 | zcache_flush_found++; |
| 2703 | local_irq_restore(flags); |
| 2704 | return ret; |
| 2705 | } |
| 2706 | |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 2707 | int zcache_flush_object(int cli_id, int pool_id, struct tmem_oid *oidp) |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 2708 | { |
| 2709 | struct tmem_pool *pool; |
| 2710 | int ret = -1; |
| 2711 | unsigned long flags; |
| 2712 | |
| 2713 | local_irq_save(flags); |
| 2714 | zcache_flobj_total++; |
| 2715 | pool = zcache_get_pool_by_id(cli_id, pool_id); |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 2716 | ramster_do_preload_flnode_only(pool); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 2717 | if (likely(pool != NULL)) { |
| 2718 | if (atomic_read(&pool->obj_count) > 0) |
| 2719 | ret = tmem_flush_object(pool, oidp); |
| 2720 | zcache_put_pool(pool); |
| 2721 | } |
| 2722 | if (ret >= 0) |
| 2723 | zcache_flobj_found++; |
| 2724 | local_irq_restore(flags); |
| 2725 | return ret; |
| 2726 | } |
| 2727 | |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 2728 | int zcache_client_destroy_pool(int cli_id, int pool_id) |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 2729 | { |
| 2730 | struct tmem_pool *pool = NULL; |
| 2731 | struct zcache_client *cli = NULL; |
| 2732 | int ret = -1; |
| 2733 | |
| 2734 | if (pool_id < 0) |
| 2735 | goto out; |
| 2736 | if (cli_id == LOCAL_CLIENT) |
| 2737 | cli = &zcache_host; |
| 2738 | else if ((unsigned int)cli_id < MAX_CLIENTS) |
| 2739 | cli = &zcache_clients[cli_id]; |
| 2740 | if (cli == NULL) |
| 2741 | goto out; |
| 2742 | atomic_inc(&cli->refcount); |
| 2743 | pool = cli->tmem_pools[pool_id]; |
| 2744 | if (pool == NULL) |
| 2745 | goto out; |
| 2746 | cli->tmem_pools[pool_id] = NULL; |
| 2747 | /* wait for pool activity on other cpus to quiesce */ |
| 2748 | while (atomic_read(&pool->refcount) != 0) |
| 2749 | ; |
| 2750 | atomic_dec(&cli->refcount); |
| 2751 | local_bh_disable(); |
| 2752 | ret = tmem_destroy_pool(pool); |
| 2753 | local_bh_enable(); |
| 2754 | kfree(pool); |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 2755 | pr_info("ramster: destroyed pool id=%d cli_id=%d\n", pool_id, cli_id); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 2756 | out: |
| 2757 | return ret; |
| 2758 | } |
| 2759 | |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 2760 | static int zcache_destroy_pool(int pool_id) |
| 2761 | { |
| 2762 | return zcache_client_destroy_pool(LOCAL_CLIENT, pool_id); |
| 2763 | } |
| 2764 | |
| 2765 | int zcache_new_pool(uint16_t cli_id, uint32_t flags) |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 2766 | { |
| 2767 | int poolid = -1; |
| 2768 | struct tmem_pool *pool; |
| 2769 | struct zcache_client *cli = NULL; |
| 2770 | |
| 2771 | if (cli_id == LOCAL_CLIENT) |
| 2772 | cli = &zcache_host; |
| 2773 | else if ((unsigned int)cli_id < MAX_CLIENTS) |
| 2774 | cli = &zcache_clients[cli_id]; |
| 2775 | if (cli == NULL) |
| 2776 | goto out; |
| 2777 | atomic_inc(&cli->refcount); |
| 2778 | pool = kmalloc(sizeof(struct tmem_pool), GFP_ATOMIC); |
| 2779 | if (pool == NULL) { |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 2780 | pr_info("ramster: pool creation failed: out of memory\n"); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 2781 | goto out; |
| 2782 | } |
| 2783 | |
| 2784 | for (poolid = 0; poolid < MAX_POOLS_PER_CLIENT; poolid++) |
| 2785 | if (cli->tmem_pools[poolid] == NULL) |
| 2786 | break; |
| 2787 | if (poolid >= MAX_POOLS_PER_CLIENT) { |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 2788 | pr_info("ramster: pool creation failed: max exceeded\n"); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 2789 | kfree(pool); |
| 2790 | poolid = -1; |
| 2791 | goto out; |
| 2792 | } |
| 2793 | atomic_set(&pool->refcount, 0); |
| 2794 | pool->client = cli; |
| 2795 | pool->pool_id = poolid; |
| 2796 | tmem_new_pool(pool, flags); |
| 2797 | cli->tmem_pools[poolid] = pool; |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 2798 | if (cli_id == LOCAL_CLIENT) |
| 2799 | pr_info("ramster: created %s tmem pool, id=%d, local client\n", |
| 2800 | flags & TMEM_POOL_PERSIST ? "persistent" : "ephemeral", |
| 2801 | poolid); |
| 2802 | else |
| 2803 | pr_info("ramster: created %s tmem pool, id=%d, client=%d\n", |
| 2804 | flags & TMEM_POOL_PERSIST ? "persistent" : "ephemeral", |
| 2805 | poolid, cli_id); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 2806 | out: |
| 2807 | if (cli != NULL) |
| 2808 | atomic_dec(&cli->refcount); |
| 2809 | return poolid; |
| 2810 | } |
| 2811 | |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 2812 | static int zcache_local_new_pool(uint32_t flags) |
| 2813 | { |
| 2814 | return zcache_new_pool(LOCAL_CLIENT, flags); |
| 2815 | } |
| 2816 | |
| 2817 | int zcache_autocreate_pool(int cli_id, int pool_id, bool ephemeral) |
| 2818 | { |
| 2819 | struct tmem_pool *pool; |
| 2820 | struct zcache_client *cli = NULL; |
| 2821 | uint32_t flags = ephemeral ? 0 : TMEM_POOL_PERSIST; |
| 2822 | int ret = -1; |
| 2823 | |
| 2824 | if (cli_id == LOCAL_CLIENT) |
| 2825 | goto out; |
| 2826 | if (pool_id >= MAX_POOLS_PER_CLIENT) |
| 2827 | goto out; |
| 2828 | else if ((unsigned int)cli_id < MAX_CLIENTS) |
| 2829 | cli = &zcache_clients[cli_id]; |
| 2830 | if ((ephemeral && !use_cleancache) || (!ephemeral && !use_frontswap)) |
| 2831 | BUG(); /* FIXME, handle more gracefully later */ |
| 2832 | if (!cli->allocated) { |
| 2833 | if (zcache_new_client(cli_id)) |
| 2834 | BUG(); /* FIXME, handle more gracefully later */ |
| 2835 | cli = &zcache_clients[cli_id]; |
| 2836 | } |
| 2837 | atomic_inc(&cli->refcount); |
| 2838 | pool = cli->tmem_pools[pool_id]; |
| 2839 | if (pool != NULL) { |
| 2840 | if (pool->persistent && ephemeral) { |
| 2841 | pr_err("zcache_autocreate_pool: type mismatch\n"); |
| 2842 | goto out; |
| 2843 | } |
| 2844 | ret = 0; |
| 2845 | goto out; |
| 2846 | } |
| 2847 | pool = kmalloc(sizeof(struct tmem_pool), GFP_KERNEL); |
| 2848 | if (pool == NULL) { |
| 2849 | pr_info("ramster: pool creation failed: out of memory\n"); |
| 2850 | goto out; |
| 2851 | } |
| 2852 | atomic_set(&pool->refcount, 0); |
| 2853 | pool->client = cli; |
| 2854 | pool->pool_id = pool_id; |
| 2855 | tmem_new_pool(pool, flags); |
| 2856 | cli->tmem_pools[pool_id] = pool; |
| 2857 | pr_info("ramster: AUTOcreated %s tmem poolid=%d, for remote client=%d\n", |
| 2858 | flags & TMEM_POOL_PERSIST ? "persistent" : "ephemeral", |
| 2859 | pool_id, cli_id); |
| 2860 | ret = 0; |
| 2861 | out: |
| 2862 | if (cli == NULL) |
| 2863 | BUG(); /* FIXME, handle more gracefully later */ |
| 2864 | /* pr_err("zcache_autocreate_pool: failed\n"); */ |
| 2865 | if (cli != NULL) |
| 2866 | atomic_dec(&cli->refcount); |
| 2867 | return ret; |
| 2868 | } |
| 2869 | |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 2870 | /********** |
| 2871 | * Two kernel functionalities currently can be layered on top of tmem. |
| 2872 | * These are "cleancache" which is used as a second-chance cache for clean |
| 2873 | * page cache pages; and "frontswap" which is used for swap pages |
| 2874 | * to avoid writes to disk. A generic "shim" is provided here for each |
| 2875 | * to translate in-kernel semantics to zcache semantics. |
| 2876 | */ |
| 2877 | |
| 2878 | #ifdef CONFIG_CLEANCACHE |
| 2879 | static void zcache_cleancache_put_page(int pool_id, |
| 2880 | struct cleancache_filekey key, |
| 2881 | pgoff_t index, struct page *page) |
| 2882 | { |
| 2883 | u32 ind = (u32) index; |
| 2884 | struct tmem_oid oid = *(struct tmem_oid *)&key; |
| 2885 | |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 2886 | #ifdef __PG_WAS_ACTIVE |
| 2887 | if (!PageWasActive(page)) { |
| 2888 | zcache_nonactive_puts++; |
| 2889 | return; |
| 2890 | } |
| 2891 | #endif |
| 2892 | if (likely(ind == index)) { |
| 2893 | char *kva = page_address(page); |
| 2894 | |
| 2895 | (void)zcache_put(LOCAL_CLIENT, pool_id, &oid, index, |
| 2896 | kva, PAGE_SIZE, 0, 1); |
| 2897 | } |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 2898 | } |
| 2899 | |
| 2900 | static int zcache_cleancache_get_page(int pool_id, |
| 2901 | struct cleancache_filekey key, |
| 2902 | pgoff_t index, struct page *page) |
| 2903 | { |
| 2904 | u32 ind = (u32) index; |
| 2905 | struct tmem_oid oid = *(struct tmem_oid *)&key; |
| 2906 | int ret = -1; |
| 2907 | |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 2908 | preempt_disable(); |
| 2909 | if (likely(ind == index)) { |
| 2910 | char *kva = page_address(page); |
| 2911 | size_t size = PAGE_SIZE; |
| 2912 | |
| 2913 | ret = zcache_get(LOCAL_CLIENT, pool_id, &oid, index, |
| 2914 | kva, &size, 0, 0); |
| 2915 | #ifdef __PG_WAS_ACTIVE |
| 2916 | if (ret == 0) |
| 2917 | SetPageWasActive(page); |
| 2918 | #endif |
| 2919 | } |
| 2920 | preempt_enable(); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 2921 | return ret; |
| 2922 | } |
| 2923 | |
| 2924 | static void zcache_cleancache_flush_page(int pool_id, |
| 2925 | struct cleancache_filekey key, |
| 2926 | pgoff_t index) |
| 2927 | { |
| 2928 | u32 ind = (u32) index; |
| 2929 | struct tmem_oid oid = *(struct tmem_oid *)&key; |
| 2930 | |
| 2931 | if (likely(ind == index)) |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 2932 | (void)zcache_flush(LOCAL_CLIENT, pool_id, &oid, ind); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 2933 | } |
| 2934 | |
| 2935 | static void zcache_cleancache_flush_inode(int pool_id, |
| 2936 | struct cleancache_filekey key) |
| 2937 | { |
| 2938 | struct tmem_oid oid = *(struct tmem_oid *)&key; |
| 2939 | |
| 2940 | (void)zcache_flush_object(LOCAL_CLIENT, pool_id, &oid); |
| 2941 | } |
| 2942 | |
| 2943 | static void zcache_cleancache_flush_fs(int pool_id) |
| 2944 | { |
| 2945 | if (pool_id >= 0) |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 2946 | (void)zcache_destroy_pool(pool_id); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 2947 | } |
| 2948 | |
| 2949 | static int zcache_cleancache_init_fs(size_t pagesize) |
| 2950 | { |
| 2951 | BUG_ON(sizeof(struct cleancache_filekey) != |
| 2952 | sizeof(struct tmem_oid)); |
| 2953 | BUG_ON(pagesize != PAGE_SIZE); |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 2954 | return zcache_local_new_pool(0); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 2955 | } |
| 2956 | |
| 2957 | static int zcache_cleancache_init_shared_fs(char *uuid, size_t pagesize) |
| 2958 | { |
| 2959 | /* shared pools are unsupported and map to private */ |
| 2960 | BUG_ON(sizeof(struct cleancache_filekey) != |
| 2961 | sizeof(struct tmem_oid)); |
| 2962 | BUG_ON(pagesize != PAGE_SIZE); |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 2963 | return zcache_local_new_pool(0); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 2964 | } |
| 2965 | |
| 2966 | static struct cleancache_ops zcache_cleancache_ops = { |
| 2967 | .put_page = zcache_cleancache_put_page, |
| 2968 | .get_page = zcache_cleancache_get_page, |
| 2969 | .invalidate_page = zcache_cleancache_flush_page, |
| 2970 | .invalidate_inode = zcache_cleancache_flush_inode, |
| 2971 | .invalidate_fs = zcache_cleancache_flush_fs, |
| 2972 | .init_shared_fs = zcache_cleancache_init_shared_fs, |
| 2973 | .init_fs = zcache_cleancache_init_fs |
| 2974 | }; |
| 2975 | |
| 2976 | struct cleancache_ops zcache_cleancache_register_ops(void) |
| 2977 | { |
| 2978 | struct cleancache_ops old_ops = |
| 2979 | cleancache_register_ops(&zcache_cleancache_ops); |
| 2980 | |
| 2981 | return old_ops; |
| 2982 | } |
| 2983 | #endif |
| 2984 | |
| 2985 | #ifdef CONFIG_FRONTSWAP |
| 2986 | /* a single tmem poolid is used for all frontswap "types" (swapfiles) */ |
| 2987 | static int zcache_frontswap_poolid = -1; |
| 2988 | |
| 2989 | /* |
| 2990 | * Swizzling increases objects per swaptype, increasing tmem concurrency |
| 2991 | * for heavy swaploads. Later, larger nr_cpus -> larger SWIZ_BITS |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 2992 | */ |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 2993 | #define SWIZ_BITS 8 |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 2994 | #define SWIZ_MASK ((1 << SWIZ_BITS) - 1) |
| 2995 | #define _oswiz(_type, _ind) ((_type << SWIZ_BITS) | (_ind & SWIZ_MASK)) |
| 2996 | #define iswiz(_ind) (_ind >> SWIZ_BITS) |
| 2997 | |
| 2998 | static inline struct tmem_oid oswiz(unsigned type, u32 ind) |
| 2999 | { |
| 3000 | struct tmem_oid oid = { .oid = { 0 } }; |
| 3001 | oid.oid[0] = _oswiz(type, ind); |
| 3002 | return oid; |
| 3003 | } |
| 3004 | |
Konrad Rzeszutek Wilk | 165c8ae | 2012-05-15 11:32:15 -0400 | [diff] [blame] | 3005 | static int zcache_frontswap_store(unsigned type, pgoff_t offset, |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 3006 | struct page *page) |
| 3007 | { |
| 3008 | u64 ind64 = (u64)offset; |
| 3009 | u32 ind = (u32)offset; |
| 3010 | struct tmem_oid oid = oswiz(type, ind); |
| 3011 | int ret = -1; |
| 3012 | unsigned long flags; |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 3013 | char *kva; |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 3014 | |
| 3015 | BUG_ON(!PageLocked(page)); |
| 3016 | if (likely(ind64 == ind)) { |
| 3017 | local_irq_save(flags); |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 3018 | kva = page_address(page); |
| 3019 | ret = zcache_put(LOCAL_CLIENT, zcache_frontswap_poolid, |
| 3020 | &oid, iswiz(ind), kva, PAGE_SIZE, 0, 0); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 3021 | local_irq_restore(flags); |
| 3022 | } |
| 3023 | return ret; |
| 3024 | } |
| 3025 | |
| 3026 | /* returns 0 if the page was successfully gotten from frontswap, -1 if |
| 3027 | * was not present (should never happen!) */ |
Konrad Rzeszutek Wilk | 165c8ae | 2012-05-15 11:32:15 -0400 | [diff] [blame] | 3028 | static int zcache_frontswap_load(unsigned type, pgoff_t offset, |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 3029 | struct page *page) |
| 3030 | { |
| 3031 | u64 ind64 = (u64)offset; |
| 3032 | u32 ind = (u32)offset; |
| 3033 | struct tmem_oid oid = oswiz(type, ind); |
| 3034 | int ret = -1; |
| 3035 | |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 3036 | preempt_disable(); /* FIXME, remove this? */ |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 3037 | BUG_ON(!PageLocked(page)); |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 3038 | if (likely(ind64 == ind)) { |
| 3039 | char *kva = page_address(page); |
| 3040 | size_t size = PAGE_SIZE; |
| 3041 | |
| 3042 | ret = zcache_get(LOCAL_CLIENT, zcache_frontswap_poolid, |
| 3043 | &oid, iswiz(ind), kva, &size, 0, -1); |
| 3044 | } |
| 3045 | preempt_enable(); /* FIXME, remove this? */ |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 3046 | return ret; |
| 3047 | } |
| 3048 | |
| 3049 | /* flush a single page from frontswap */ |
| 3050 | static void zcache_frontswap_flush_page(unsigned type, pgoff_t offset) |
| 3051 | { |
| 3052 | u64 ind64 = (u64)offset; |
| 3053 | u32 ind = (u32)offset; |
| 3054 | struct tmem_oid oid = oswiz(type, ind); |
| 3055 | |
| 3056 | if (likely(ind64 == ind)) |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 3057 | (void)zcache_flush(LOCAL_CLIENT, zcache_frontswap_poolid, |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 3058 | &oid, iswiz(ind)); |
| 3059 | } |
| 3060 | |
| 3061 | /* flush all pages from the passed swaptype */ |
| 3062 | static void zcache_frontswap_flush_area(unsigned type) |
| 3063 | { |
| 3064 | struct tmem_oid oid; |
| 3065 | int ind; |
| 3066 | |
| 3067 | for (ind = SWIZ_MASK; ind >= 0; ind--) { |
| 3068 | oid = oswiz(type, ind); |
| 3069 | (void)zcache_flush_object(LOCAL_CLIENT, |
| 3070 | zcache_frontswap_poolid, &oid); |
| 3071 | } |
| 3072 | } |
| 3073 | |
| 3074 | static void zcache_frontswap_init(unsigned ignored) |
| 3075 | { |
| 3076 | /* a single tmem poolid is used for all frontswap "types" (swapfiles) */ |
| 3077 | if (zcache_frontswap_poolid < 0) |
| 3078 | zcache_frontswap_poolid = |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 3079 | zcache_local_new_pool(TMEM_POOL_PERSIST); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 3080 | } |
| 3081 | |
| 3082 | static struct frontswap_ops zcache_frontswap_ops = { |
Konrad Rzeszutek Wilk | 165c8ae | 2012-05-15 11:32:15 -0400 | [diff] [blame] | 3083 | .store = zcache_frontswap_store, |
| 3084 | .load = zcache_frontswap_load, |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 3085 | .invalidate_page = zcache_frontswap_flush_page, |
| 3086 | .invalidate_area = zcache_frontswap_flush_area, |
| 3087 | .init = zcache_frontswap_init |
| 3088 | }; |
| 3089 | |
| 3090 | struct frontswap_ops zcache_frontswap_register_ops(void) |
| 3091 | { |
| 3092 | struct frontswap_ops old_ops = |
| 3093 | frontswap_register_ops(&zcache_frontswap_ops); |
| 3094 | |
| 3095 | return old_ops; |
| 3096 | } |
| 3097 | #endif |
| 3098 | |
| 3099 | /* |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 3100 | * frontswap selfshrinking |
| 3101 | */ |
| 3102 | |
| 3103 | #ifdef CONFIG_FRONTSWAP |
| 3104 | /* In HZ, controls frequency of worker invocation. */ |
| 3105 | static unsigned int selfshrink_interval __read_mostly = 5; |
| 3106 | |
| 3107 | static void selfshrink_process(struct work_struct *work); |
| 3108 | static DECLARE_DELAYED_WORK(selfshrink_worker, selfshrink_process); |
| 3109 | |
| 3110 | /* Enable/disable with sysfs. */ |
| 3111 | static bool frontswap_selfshrinking __read_mostly; |
| 3112 | |
| 3113 | /* Enable/disable with kernel boot option. */ |
| 3114 | static bool use_frontswap_selfshrink __initdata = true; |
| 3115 | |
| 3116 | /* |
| 3117 | * The default values for the following parameters were deemed reasonable |
| 3118 | * by experimentation, may be workload-dependent, and can all be |
| 3119 | * adjusted via sysfs. |
| 3120 | */ |
| 3121 | |
| 3122 | /* Control rate for frontswap shrinking. Higher hysteresis is slower. */ |
| 3123 | static unsigned int frontswap_hysteresis __read_mostly = 20; |
| 3124 | |
| 3125 | /* |
| 3126 | * Number of selfshrink worker invocations to wait before observing that |
| 3127 | * frontswap selfshrinking should commence. Note that selfshrinking does |
| 3128 | * not use a separate worker thread. |
| 3129 | */ |
| 3130 | static unsigned int frontswap_inertia __read_mostly = 3; |
| 3131 | |
| 3132 | /* Countdown to next invocation of frontswap_shrink() */ |
| 3133 | static unsigned long frontswap_inertia_counter; |
| 3134 | |
| 3135 | /* |
| 3136 | * Invoked by the selfshrink worker thread, uses current number of pages |
| 3137 | * in frontswap (frontswap_curr_pages()), previous status, and control |
| 3138 | * values (hysteresis and inertia) to determine if frontswap should be |
| 3139 | * shrunk and what the new frontswap size should be. Note that |
| 3140 | * frontswap_shrink is essentially a partial swapoff that immediately |
| 3141 | * transfers pages from the "swap device" (frontswap) back into kernel |
| 3142 | * RAM; despite the name, frontswap "shrinking" is very different from |
| 3143 | * the "shrinker" interface used by the kernel MM subsystem to reclaim |
| 3144 | * memory. |
| 3145 | */ |
| 3146 | static void frontswap_selfshrink(void) |
| 3147 | { |
| 3148 | static unsigned long cur_frontswap_pages; |
| 3149 | static unsigned long last_frontswap_pages; |
| 3150 | static unsigned long tgt_frontswap_pages; |
| 3151 | |
| 3152 | last_frontswap_pages = cur_frontswap_pages; |
| 3153 | cur_frontswap_pages = frontswap_curr_pages(); |
| 3154 | if (!cur_frontswap_pages || |
| 3155 | (cur_frontswap_pages > last_frontswap_pages)) { |
| 3156 | frontswap_inertia_counter = frontswap_inertia; |
| 3157 | return; |
| 3158 | } |
| 3159 | if (frontswap_inertia_counter && --frontswap_inertia_counter) |
| 3160 | return; |
| 3161 | if (cur_frontswap_pages <= frontswap_hysteresis) |
| 3162 | tgt_frontswap_pages = 0; |
| 3163 | else |
| 3164 | tgt_frontswap_pages = cur_frontswap_pages - |
| 3165 | (cur_frontswap_pages / frontswap_hysteresis); |
| 3166 | frontswap_shrink(tgt_frontswap_pages); |
| 3167 | } |
| 3168 | |
| 3169 | static int __init ramster_nofrontswap_selfshrink_setup(char *s) |
| 3170 | { |
| 3171 | use_frontswap_selfshrink = false; |
| 3172 | return 1; |
| 3173 | } |
| 3174 | |
| 3175 | __setup("noselfshrink", ramster_nofrontswap_selfshrink_setup); |
| 3176 | |
| 3177 | static void selfshrink_process(struct work_struct *work) |
| 3178 | { |
| 3179 | if (frontswap_selfshrinking && frontswap_enabled) { |
| 3180 | frontswap_selfshrink(); |
| 3181 | schedule_delayed_work(&selfshrink_worker, |
| 3182 | selfshrink_interval * HZ); |
| 3183 | } |
| 3184 | } |
| 3185 | |
| 3186 | static int ramster_enabled; |
| 3187 | |
| 3188 | static int __init ramster_selfshrink_init(void) |
| 3189 | { |
| 3190 | frontswap_selfshrinking = ramster_enabled && use_frontswap_selfshrink; |
| 3191 | if (frontswap_selfshrinking) |
| 3192 | pr_info("ramster: Initializing frontswap " |
| 3193 | "selfshrinking driver.\n"); |
| 3194 | else |
| 3195 | return -ENODEV; |
| 3196 | |
| 3197 | schedule_delayed_work(&selfshrink_worker, selfshrink_interval * HZ); |
| 3198 | |
| 3199 | return 0; |
| 3200 | } |
| 3201 | |
| 3202 | subsys_initcall(ramster_selfshrink_init); |
| 3203 | #endif |
| 3204 | |
| 3205 | /* |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 3206 | * zcache initialization |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 3207 | * NOTE FOR NOW ramster MUST BE PROVIDED AS A KERNEL BOOT PARAMETER OR |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 3208 | * NOTHING HAPPENS! |
| 3209 | */ |
| 3210 | |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 3211 | static int ramster_enabled; |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 3212 | |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 3213 | static int __init enable_ramster(char *s) |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 3214 | { |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 3215 | ramster_enabled = 1; |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 3216 | return 1; |
| 3217 | } |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 3218 | __setup("ramster", enable_ramster); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 3219 | |
| 3220 | /* allow independent dynamic disabling of cleancache and frontswap */ |
| 3221 | |
| 3222 | static int use_cleancache = 1; |
| 3223 | |
| 3224 | static int __init no_cleancache(char *s) |
| 3225 | { |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 3226 | pr_info("INIT no_cleancache called\n"); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 3227 | use_cleancache = 0; |
| 3228 | return 1; |
| 3229 | } |
| 3230 | |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 3231 | /* |
| 3232 | * FIXME: need to guarantee this gets checked before zcache_init is called |
| 3233 | * What is the correct way to achieve this? |
| 3234 | */ |
| 3235 | early_param("nocleancache", no_cleancache); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 3236 | |
| 3237 | static int use_frontswap = 1; |
| 3238 | |
| 3239 | static int __init no_frontswap(char *s) |
| 3240 | { |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 3241 | pr_info("INIT no_frontswap called\n"); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 3242 | use_frontswap = 0; |
| 3243 | return 1; |
| 3244 | } |
| 3245 | |
| 3246 | __setup("nofrontswap", no_frontswap); |
| 3247 | |
| 3248 | static int __init zcache_init(void) |
| 3249 | { |
| 3250 | int ret = 0; |
| 3251 | |
| 3252 | #ifdef CONFIG_SYSFS |
| 3253 | ret = sysfs_create_group(mm_kobj, &zcache_attr_group); |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 3254 | ret = sysfs_create_group(mm_kobj, &ramster_attr_group); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 3255 | if (ret) { |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 3256 | pr_err("ramster: can't create sysfs\n"); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 3257 | goto out; |
| 3258 | } |
| 3259 | #endif /* CONFIG_SYSFS */ |
| 3260 | #if defined(CONFIG_CLEANCACHE) || defined(CONFIG_FRONTSWAP) |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 3261 | if (ramster_enabled) { |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 3262 | unsigned int cpu; |
| 3263 | |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 3264 | (void)r2net_register_handlers(); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 3265 | tmem_register_hostops(&zcache_hostops); |
| 3266 | tmem_register_pamops(&zcache_pamops); |
| 3267 | ret = register_cpu_notifier(&zcache_cpu_notifier_block); |
| 3268 | if (ret) { |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 3269 | pr_err("ramster: can't register cpu notifier\n"); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 3270 | goto out; |
| 3271 | } |
| 3272 | for_each_online_cpu(cpu) { |
| 3273 | void *pcpu = (void *)(long)cpu; |
| 3274 | zcache_cpu_notifier(&zcache_cpu_notifier_block, |
| 3275 | CPU_UP_PREPARE, pcpu); |
| 3276 | } |
| 3277 | } |
| 3278 | zcache_objnode_cache = kmem_cache_create("zcache_objnode", |
| 3279 | sizeof(struct tmem_objnode), 0, 0, NULL); |
| 3280 | zcache_obj_cache = kmem_cache_create("zcache_obj", |
| 3281 | sizeof(struct tmem_obj), 0, 0, NULL); |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 3282 | ramster_flnode_cache = kmem_cache_create("ramster_flnode", |
| 3283 | sizeof(struct flushlist_node), 0, 0, NULL); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 3284 | #endif |
| 3285 | #ifdef CONFIG_CLEANCACHE |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 3286 | pr_info("INIT ramster_enabled=%d use_cleancache=%d\n", |
| 3287 | ramster_enabled, use_cleancache); |
| 3288 | if (ramster_enabled && use_cleancache) { |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 3289 | struct cleancache_ops old_ops; |
| 3290 | |
| 3291 | zbud_init(); |
| 3292 | register_shrinker(&zcache_shrinker); |
| 3293 | old_ops = zcache_cleancache_register_ops(); |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 3294 | pr_info("ramster: cleancache enabled using kernel " |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 3295 | "transcendent memory and compression buddies\n"); |
| 3296 | if (old_ops.init_fs != NULL) |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 3297 | pr_warning("ramster: cleancache_ops overridden"); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 3298 | } |
| 3299 | #endif |
| 3300 | #ifdef CONFIG_FRONTSWAP |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 3301 | pr_info("INIT ramster_enabled=%d use_frontswap=%d\n", |
| 3302 | ramster_enabled, use_frontswap); |
| 3303 | if (ramster_enabled && use_frontswap) { |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 3304 | struct frontswap_ops old_ops; |
| 3305 | |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 3306 | zcache_new_client(LOCAL_CLIENT); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 3307 | old_ops = zcache_frontswap_register_ops(); |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 3308 | pr_info("ramster: frontswap enabled using kernel " |
Greg Kroah-Hartman | 00bf19f | 2012-05-16 08:09:35 -0700 | [diff] [blame] | 3309 | "transcendent memory and xvmalloc\n"); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 3310 | if (old_ops.init != NULL) |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 3311 | pr_warning("ramster: frontswap_ops overridden"); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 3312 | } |
Dan Magenheimer | c89126e | 2012-02-15 07:54:18 -0800 | [diff] [blame] | 3313 | if (ramster_enabled && (use_frontswap || use_cleancache)) |
| 3314 | ramster_remotify_init(); |
Dan Magenheimer | 19ee3ef | 2012-02-15 07:54:16 -0800 | [diff] [blame] | 3315 | #endif |
| 3316 | out: |
| 3317 | return ret; |
| 3318 | } |
| 3319 | |
| 3320 | module_init(zcache_init) |