drivers/staging/lustre/include/linux/libcfs/libcfs_private.h

   1 /*
   2  * GPL HEADER START
   3  *
   4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 only,
   8  * as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * General Public License version 2 for more details (a copy is included
  14  * in the LICENSE file that accompanied this code).
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * version 2 along with this program; If not, see
  18  * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
  19  *
  20  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  21  * CA 95054 USA or visit www.sun.com if you need additional information or
  22  * have any questions.
  23  *
  24  * GPL HEADER END
  25  */
  26 /*
  27  * Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
  28  * Use is subject to license terms.
  29  *
  30  * Copyright (c) 2011, 2012, Intel Corporation.
  31  */
  32 /*
  33  * This file is part of Lustre, http://www.lustre.org/
  34  * Lustre is a trademark of Sun Microsystems, Inc.
  35  *
  36  * libcfs/include/libcfs/libcfs_private.h
  37  *
  38  * Various defines for libcfs.
  39  *
  40  */
  41
  42 #ifndef __LIBCFS_PRIVATE_H__
  43 #define __LIBCFS_PRIVATE_H__
  44
  45 #ifndef DEBUG_SUBSYSTEM
  46 # define DEBUG_SUBSYSTEM S_UNDEFINED
  47 #endif
  48
  49 /*
  50  * When this is on, LASSERT macro includes check for assignment used instead
  51  * of equality check, but doesn't have unlikely(). Turn this on from time to
  52  * time to make test-builds. This shouldn't be on for production release.
  53  */
  54 #define LASSERT_CHECKED (0)
  55
  56 #define LASSERTF(cond, fmt, ...)                                        \
  57 do {                                                                    \
  58         if (unlikely(!(cond))) {                                        \
  59                 LIBCFS_DEBUG_MSG_DATA_DECL(__msg_data, D_EMERG, NULL);  \
  60                 libcfs_debug_msg(&__msg_data,                           \
  61                                  "ASSERTION( %s ) failed: " fmt, #cond, \
  62                                  ## __VA_ARGS__);                       \
  63                 lbug_with_loc(&__msg_data);                             \
  64         }                                                               \
  65 } while (0)
  66
  67 #define LASSERT(cond) LASSERTF(cond, "\n")
  68
  69 #ifdef CONFIG_LUSTRE_DEBUG_EXPENSIVE_CHECK
  70 /**
  71  * This is for more expensive checks that one doesn't want to be enabled all
  72  * the time. LINVRNT() has to be explicitly enabled by
  73  * CONFIG_LUSTRE_DEBUG_EXPENSIVE_CHECK option.
  74  */
  75 # define LINVRNT(exp) LASSERT(exp)
  76 #else
  77 # define LINVRNT(exp) ((void)sizeof !!(exp))
  78 #endif
  79
  80 #define KLASSERT(e) LASSERT(e)
  81
  82 void __noreturn lbug_with_loc(struct libcfs_debug_msg_data *);
  83
  84 #define LBUG()                                                    \
  85 do {                                                                \
  86         LIBCFS_DEBUG_MSG_DATA_DECL(msgdata, D_EMERG, NULL);          \
  87         lbug_with_loc(&msgdata);                                        \
  88 } while (0)
  89
  90 #ifndef LIBCFS_VMALLOC_SIZE
  91 #define LIBCFS_VMALLOC_SIZE     (2 << PAGE_CACHE_SHIFT) /* 2 pages */
  92 #endif
  93
  94 #define LIBCFS_ALLOC_PRE(size, mask)                                        \
  95 do {                                                                        \
  96         LASSERT(!in_interrupt() ||                                          \
  97                 ((size) <= LIBCFS_VMALLOC_SIZE &&                           \
  98                  !gfpflags_allow_blocking(mask)));                          \
  99 } while (0)
 100
 101 #define LIBCFS_ALLOC_POST(ptr, size)                                        \
 102 do {                                                                        \
 103         if (unlikely((ptr) == NULL)) {                                      \
 104                 CERROR("LNET: out of memory at %s:%d (tried to alloc '"     \
 105                        #ptr "' = %d)\n", __FILE__, __LINE__, (int)(size));  \
 106         } else {                                                            \
 107                 memset((ptr), 0, (size));                                   \
 108         }                                                                   \
 109 } while (0)
 110
 111 /**
 112  * allocate memory with GFP flags @mask
 113  */
 114 #define LIBCFS_ALLOC_GFP(ptr, size, mask)                                   \
 115 do {                                                                        \
 116         LIBCFS_ALLOC_PRE((size), (mask));                                   \
 117         (ptr) = (size) <= LIBCFS_VMALLOC_SIZE ?                             \
 118                 kmalloc((size), (mask)) : vmalloc(size);            \
 119         LIBCFS_ALLOC_POST((ptr), (size));                                   \
 120 } while (0)
 121
 122 /**
 123  * default allocator
 124  */
 125 #define LIBCFS_ALLOC(ptr, size) \
 126         LIBCFS_ALLOC_GFP(ptr, size, GFP_NOFS)
 127
 128 /**
 129  * non-sleeping allocator
 130  */
 131 #define LIBCFS_ALLOC_ATOMIC(ptr, size) \
 132         LIBCFS_ALLOC_GFP(ptr, size, GFP_ATOMIC)
 133
 134 /**
 135  * allocate memory for specified CPU partition
 136  *   \a cptab != NULL, \a cpt is CPU partition id of \a cptab
 137  *   \a cptab == NULL, \a cpt is HW NUMA node id
 138  */
 139 #define LIBCFS_CPT_ALLOC_GFP(ptr, cptab, cpt, size, mask)                   \
 140 do {                                                                        \
 141         LIBCFS_ALLOC_PRE((size), (mask));                                   \
 142         (ptr) = (size) <= LIBCFS_VMALLOC_SIZE ?                             \
 143                 kmalloc_node((size), (mask), cfs_cpt_spread_node(cptab, cpt)) :\
 144                 vmalloc_node(size, cfs_cpt_spread_node(cptab, cpt));        \
 145         LIBCFS_ALLOC_POST((ptr), (size));                                   \
 146 } while (0)
 147
 148 /** default numa allocator */
 149 #define LIBCFS_CPT_ALLOC(ptr, cptab, cpt, size)                             \
 150         LIBCFS_CPT_ALLOC_GFP(ptr, cptab, cpt, size, GFP_NOFS)
 151
 152 #define LIBCFS_FREE(ptr, size)                                    \
 153 do {                                                                \
 154         int s = (size);                                          \
 155         if (unlikely((ptr) == NULL)) {                            \
 156                 CERROR("LIBCFS: free NULL '" #ptr "' (%d bytes) at "    \
 157                        "%s:%d\n", s, __FILE__, __LINE__);              \
 158                 break;                                            \
 159         }                                                              \
 160         if (unlikely(s > LIBCFS_VMALLOC_SIZE))                    \
 161                 vfree(ptr);                                 \
 162         else                                                        \
 163                 kfree(ptr);                                       \
 164 } while (0)
 165
 166 /******************************************************************************/
 167
 168 /* htonl hack - either this, or compile with -O2. Stupid byteorder/generic.h */
 169 #if defined(__GNUC__) && (__GNUC__ >= 2) && !defined(__OPTIMIZE__)
 170 #define ___htonl(x) __cpu_to_be32(x)
 171 #define ___htons(x) __cpu_to_be16(x)
 172 #define ___ntohl(x) __be32_to_cpu(x)
 173 #define ___ntohs(x) __be16_to_cpu(x)
 174 #define htonl(x) ___htonl(x)
 175 #define ntohl(x) ___ntohl(x)
 176 #define htons(x) ___htons(x)
 177 #define ntohs(x) ___ntohs(x)
 178 #endif
 179
 180 void libcfs_run_upcall(char **argv);
 181 void libcfs_run_lbug_upcall(struct libcfs_debug_msg_data *);
 182 void libcfs_debug_dumplog(void);
 183 int libcfs_debug_init(unsigned long bufsize);
 184 int libcfs_debug_cleanup(void);
 185 int libcfs_debug_clear_buffer(void);
 186 int libcfs_debug_mark_buffer(const char *text);
 187
 188 /*
 189  * allocate per-cpu-partition data, returned value is an array of pointers,
 190  * variable can be indexed by CPU ID.
 191  *      cptable != NULL: size of array is number of CPU partitions
 192  *      cptable == NULL: size of array is number of HW cores
 193  */
 194 void *cfs_percpt_alloc(struct cfs_cpt_table *cptab, unsigned int size);
 195 /*
 196  * destroy per-cpu-partition variable
 197  */
 198 void  cfs_percpt_free(void *vars);
 199 int   cfs_percpt_number(void *vars);
 200 void *cfs_percpt_current(void *vars);
 201 void *cfs_percpt_index(void *vars, int idx);
 202
 203 #define cfs_percpt_for_each(var, i, vars)               \
 204         for (i = 0; i < cfs_percpt_number(vars) &&      \
 205                     ((var) = (vars)[i]) != NULL; i++)
 206
 207 /*
 208  * allocate a variable array, returned value is an array of pointers.
 209  * Caller can specify length of array by count.
 210  */
 211 void *cfs_array_alloc(int count, unsigned int size);
 212 void  cfs_array_free(void *vars);
 213
 214 #define LASSERT_ATOMIC_ENABLED    (1)
 215
 216 #if LASSERT_ATOMIC_ENABLED
 217
 218 /** assert value of @a is equal to @v */
 219 #define LASSERT_ATOMIC_EQ(a, v)                          \
 220 do {                                                        \
 221         LASSERTF(atomic_read(a) == v,                  \
 222                  "value: %d\n", atomic_read((a)));        \
 223 } while (0)
 224
 225 /** assert value of @a is unequal to @v */
 226 #define LASSERT_ATOMIC_NE(a, v)                          \
 227 do {                                                        \
 228         LASSERTF(atomic_read(a) != v,                  \
 229                  "value: %d\n", atomic_read((a)));        \
 230 } while (0)
 231
 232 /** assert value of @a is little than @v */
 233 #define LASSERT_ATOMIC_LT(a, v)                          \
 234 do {                                                        \
 235         LASSERTF(atomic_read(a) < v,                    \
 236                  "value: %d\n", atomic_read((a)));        \
 237 } while (0)
 238
 239 /** assert value of @a is little/equal to @v */
 240 #define LASSERT_ATOMIC_LE(a, v)                          \
 241 do {                                                        \
 242         LASSERTF(atomic_read(a) <= v,                  \
 243                  "value: %d\n", atomic_read((a)));        \
 244 } while (0)
 245
 246 /** assert value of @a is great than @v */
 247 #define LASSERT_ATOMIC_GT(a, v)                          \
 248 do {                                                        \
 249         LASSERTF(atomic_read(a) > v,                    \
 250                  "value: %d\n", atomic_read((a)));        \
 251 } while (0)
 252
 253 /** assert value of @a is great/equal to @v */
 254 #define LASSERT_ATOMIC_GE(a, v)                          \
 255 do {                                                        \
 256         LASSERTF(atomic_read(a) >= v,                  \
 257                  "value: %d\n", atomic_read((a)));        \
 258 } while (0)
 259
 260 /** assert value of @a is great than @v1 and little than @v2 */
 261 #define LASSERT_ATOMIC_GT_LT(a, v1, v2)                  \
 262 do {                                                        \
 263         int __v = atomic_read(a);                          \
 264         LASSERTF(__v > v1 && __v < v2, "value: %d\n", __v);     \
 265 } while (0)
 266
 267 /** assert value of @a is great than @v1 and little/equal to @v2 */
 268 #define LASSERT_ATOMIC_GT_LE(a, v1, v2)                  \
 269 do {                                                        \
 270         int __v = atomic_read(a);                          \
 271         LASSERTF(__v > v1 && __v <= v2, "value: %d\n", __v);    \
 272 } while (0)
 273
 274 /** assert value of @a is great/equal to @v1 and little than @v2 */
 275 #define LASSERT_ATOMIC_GE_LT(a, v1, v2)                  \
 276 do {                                                        \
 277         int __v = atomic_read(a);                          \
 278         LASSERTF(__v >= v1 && __v < v2, "value: %d\n", __v);    \
 279 } while (0)
 280
 281 /** assert value of @a is great/equal to @v1 and little/equal to @v2 */
 282 #define LASSERT_ATOMIC_GE_LE(a, v1, v2)                  \
 283 do {                                                        \
 284         int __v = atomic_read(a);                          \
 285         LASSERTF(__v >= v1 && __v <= v2, "value: %d\n", __v);   \
 286 } while (0)
 287
 288 #else /* !LASSERT_ATOMIC_ENABLED */
 289
 290 #define LASSERT_ATOMIC_EQ(a, v)          do {} while (0)
 291 #define LASSERT_ATOMIC_NE(a, v)          do {} while (0)
 292 #define LASSERT_ATOMIC_LT(a, v)          do {} while (0)
 293 #define LASSERT_ATOMIC_LE(a, v)          do {} while (0)
 294 #define LASSERT_ATOMIC_GT(a, v)          do {} while (0)
 295 #define LASSERT_ATOMIC_GE(a, v)          do {} while (0)
 296 #define LASSERT_ATOMIC_GT_LT(a, v1, v2)  do {} while (0)
 297 #define LASSERT_ATOMIC_GT_LE(a, v1, v2)  do {} while (0)
 298 #define LASSERT_ATOMIC_GE_LT(a, v1, v2)  do {} while (0)
 299 #define LASSERT_ATOMIC_GE_LE(a, v1, v2)  do {} while (0)
 300
 301 #endif /* LASSERT_ATOMIC_ENABLED */
 302
 303 #define LASSERT_ATOMIC_ZERO(a)            LASSERT_ATOMIC_EQ(a, 0)
 304 #define LASSERT_ATOMIC_POS(a)              LASSERT_ATOMIC_GT(a, 0)
 305
 306 #define CFS_ALLOC_PTR(ptr)      LIBCFS_ALLOC(ptr, sizeof(*(ptr)))
 307 #define CFS_FREE_PTR(ptr)       LIBCFS_FREE(ptr, sizeof(*(ptr)))
 308
 309 /*
 310  * percpu partition lock
 311  *
 312  * There are some use-cases like this in Lustre:
 313  * . each CPU partition has it's own private data which is frequently changed,
 314  *   and mostly by the local CPU partition.
 315  * . all CPU partitions share some global data, these data are rarely changed.
 316  *
 317  * LNet is typical example.
 318  * CPU partition lock is designed for this kind of use-cases:
 319  * . each CPU partition has it's own private lock
 320  * . change on private data just needs to take the private lock
 321  * . read on shared data just needs to take _any_ of private locks
 322  * . change on shared data needs to take _all_ private locks,
 323  *   which is slow and should be really rare.
 324  */
 325
 326 enum {
 327         CFS_PERCPT_LOCK_EX      = -1, /* negative */
 328 };
 329
 330 struct cfs_percpt_lock {
 331         /* cpu-partition-table for this lock */
 332         struct cfs_cpt_table    *pcl_cptab;
 333         /* exclusively locked */
 334         unsigned int            pcl_locked;
 335         /* private lock table */
 336         spinlock_t              **pcl_locks;
 337 };
 338
 339 /* return number of private locks */
 340 static inline int
 341 cfs_percpt_lock_num(struct cfs_percpt_lock *pcl)
 342 {
 343         return cfs_cpt_number(pcl->pcl_cptab);
 344 }
 345
 346 /*
 347  * create a cpu-partition lock based on CPU partition table \a cptab,
 348  * each private lock has extra \a psize bytes padding data
 349  */
 350 struct cfs_percpt_lock *cfs_percpt_lock_alloc(struct cfs_cpt_table *cptab);
 351 /* destroy a cpu-partition lock */
 352 void cfs_percpt_lock_free(struct cfs_percpt_lock *pcl);
 353
 354 /* lock private lock \a index of \a pcl */
 355 void cfs_percpt_lock(struct cfs_percpt_lock *pcl, int index);
 356 /* unlock private lock \a index of \a pcl */
 357 void cfs_percpt_unlock(struct cfs_percpt_lock *pcl, int index);
 358 /* create percpt (atomic) refcount based on @cptab */
 359 atomic_t **cfs_percpt_atomic_alloc(struct cfs_cpt_table *cptab, int val);
 360 /* destroy percpt refcount */
 361 void cfs_percpt_atomic_free(atomic_t **refs);
 362 /* return sum of all percpu refs */
 363 int cfs_percpt_atomic_summary(atomic_t **refs);
 364
 365 /** Compile-time assertion.
 366
 367  * Check an invariant described by a constant expression at compile time by
 368  * forcing a compiler error if it does not hold.  \a cond must be a constant
 369  * expression as defined by the ISO C Standard:
 370  *
 371  *       6.8.4.2  The switch statement
 372  *       ....
 373  *       [#3] The expression of each case label shall be  an  integer
 374  *       constant   expression  and  no  two  of  the  case  constant
 375  *       expressions in the same switch statement shall have the same
 376  *       value  after  conversion...
 377  *
 378  */
 379 #define CLASSERT(cond) do {switch (42) {case (cond): case 0: break; } } while (0)
 380
 381 /* max value for numeric network address */
 382 #define MAX_NUMERIC_VALUE 0xffffffff
 383
 384 /* implication */
 385 #define ergo(a, b) (!(a) || (b))
 386 /* logical equivalence */
 387 #define equi(a, b) (!!(a) == !!(b))
 388
 389 /* --------------------------------------------------------------------
 390  * Light-weight trace
 391  * Support for temporary event tracing with minimal Heisenberg effect.
 392  * -------------------------------------------------------------------- */
 393
 394 struct libcfs_device_userstate {
 395         int        ldu_memhog_pages;
 396         struct page   *ldu_memhog_root_page;
 397 };
 398
 399 #define MKSTR(ptr) ((ptr)) ? (ptr) : ""
 400
 401 static inline int cfs_size_round4(int val)
 402 {
 403         return (val + 3) & (~0x3);
 404 }
 405
 406 #ifndef HAVE_CFS_SIZE_ROUND
 407 static inline int cfs_size_round(int val)
 408 {
 409         return (val + 7) & (~0x7);
 410 }
 411
 412 #define HAVE_CFS_SIZE_ROUND
 413 #endif
 414
 415 static inline int cfs_size_round16(int val)
 416 {
 417         return (val + 0xf) & (~0xf);
 418 }
 419
 420 static inline int cfs_size_round32(int val)
 421 {
 422         return (val + 0x1f) & (~0x1f);
 423 }
 424
 425 static inline int cfs_size_round0(int val)
 426 {
 427         if (!val)
 428                 return 0;
 429         return (val + 1 + 7) & (~0x7);
 430 }
 431
 432 static inline size_t cfs_round_strlen(char *fset)
 433 {
 434         return (size_t)cfs_size_round((int)strlen(fset) + 1);
 435 }
 436
 437 #define LOGL(var, len, ptr)                                    \
 438 do {                                                        \
 439         if (var)                                                \
 440                 memcpy((char *)ptr, (const char *)var, len);    \
 441         ptr += cfs_size_round(len);                          \
 442 } while (0)
 443
 444 #define LOGU(var, len, ptr)                                    \
 445 do {                                                        \
 446         if (var)                                                \
 447                 memcpy((char *)var, (const char *)ptr, len);    \
 448         ptr += cfs_size_round(len);                          \
 449 } while (0)
 450
 451 #define LOGL0(var, len, ptr)                          \
 452 do {                                                \
 453         if (!len)                                      \
 454                 break;                            \
 455         memcpy((char *)ptr, (const char *)var, len);    \
 456         *((char *)(ptr) + len) = 0;                  \
 457         ptr += cfs_size_round(len + 1);          \
 458 } while (0)
 459
 460 #endif