1 /*
2 * kmp_lock.h -- lock header file
3 */
4
5 //===----------------------------------------------------------------------===//
6 //
7 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
8 // See https://llvm.org/LICENSE.txt for license information.
9 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
10 //
11 //===----------------------------------------------------------------------===//
12
13 #ifndef KMP_LOCK_H
14 #define KMP_LOCK_H
15
16 #include <limits.h> // CHAR_BIT
17 #include <stddef.h> // offsetof
18
19 #include "kmp_debug.h"
20 #include "kmp_os.h"
21
22 #ifdef __cplusplus
23 #include <atomic>
24
25 extern "C" {
26 #endif // __cplusplus
27
28 // ----------------------------------------------------------------------------
29 // Have to copy these definitions from kmp.h because kmp.h cannot be included
30 // due to circular dependencies. Will undef these at end of file.
31
32 #define KMP_PAD(type, sz) \
33 (sizeof(type) + (sz - ((sizeof(type) - 1) % (sz)) - 1))
34 #define KMP_GTID_DNE (-2)
35
36 // Forward declaration of ident and ident_t
37
38 struct ident;
39 typedef struct ident ident_t;
40
41 // End of copied code.
42 // ----------------------------------------------------------------------------
43
44 // We need to know the size of the area we can assume that the compiler(s)
45 // allocated for objects of type omp_lock_t and omp_nest_lock_t. The Intel
46 // compiler always allocates a pointer-sized area, as does visual studio.
47 //
48 // gcc however, only allocates 4 bytes for regular locks, even on 64-bit
49 // intel archs. It allocates at least 8 bytes for nested lock (more on
50 // recent versions), but we are bounded by the pointer-sized chunks that
51 // the Intel compiler allocates.
52
53 #if (KMP_OS_LINUX || KMP_OS_AIX) && defined(KMP_GOMP_COMPAT)
54 #define OMP_LOCK_T_SIZE sizeof(int)
55 #define OMP_NEST_LOCK_T_SIZE sizeof(void *)
56 #else
57 #define OMP_LOCK_T_SIZE sizeof(void *)
58 #define OMP_NEST_LOCK_T_SIZE sizeof(void *)
59 #endif
60
61 // The Intel compiler allocates a 32-byte chunk for a critical section.
62 // Both gcc and visual studio only allocate enough space for a pointer.
63 // Sometimes we know that the space was allocated by the Intel compiler.
64 #define OMP_CRITICAL_SIZE sizeof(void *)
65 #define INTEL_CRITICAL_SIZE 32
66
67 // lock flags
68 typedef kmp_uint32 kmp_lock_flags_t;
69
70 #define kmp_lf_critical_section 1
71
72 // When a lock table is used, the indices are of kmp_lock_index_t
73 typedef kmp_uint32 kmp_lock_index_t;
74
75 // When memory allocated for locks are on the lock pool (free list),
76 // it is treated as structs of this type.
77 struct kmp_lock_pool {
78 union kmp_user_lock *next;
79 kmp_lock_index_t index;
80 };
81
82 typedef struct kmp_lock_pool kmp_lock_pool_t;
83
84 extern void __kmp_validate_locks(void);
85
86 // ----------------------------------------------------------------------------
87 // There are 5 lock implementations:
88 // 1. Test and set locks.
89 // 2. futex locks (Linux* OS on x86 and
90 // Intel(R) Many Integrated Core Architecture)
91 // 3. Ticket (Lamport bakery) locks.
92 // 4. Queuing locks (with separate spin fields).
93 // 5. DRPA (Dynamically Reconfigurable Distributed Polling Area) locks
94 //
95 // and 3 lock purposes:
96 // 1. Bootstrap locks -- Used for a few locks available at library
97 // startup-shutdown time.
98 // These do not require non-negative global thread ID's.
99 // 2. Internal RTL locks -- Used everywhere else in the RTL
100 // 3. User locks (includes critical sections)
101 // ----------------------------------------------------------------------------
102
103 // ============================================================================
104 // Lock implementations.
105 //
106 // Test and set locks.
107 //
108 // Non-nested test and set locks differ from the other lock kinds (except
109 // futex) in that we use the memory allocated by the compiler for the lock,
110 // rather than a pointer to it.
111 //
112 // On lin32, lin_32e, and win_32, the space allocated may be as small as 4
113 // bytes, so we have to use a lock table for nested locks, and avoid accessing
114 // the depth_locked field for non-nested locks.
115 //
116 // Information normally available to the tools, such as lock location, lock
117 // usage (normal lock vs. critical section), etc. is not available with test and
118 // set locks.
119 // ----------------------------------------------------------------------------
120
121 struct kmp_base_tas_lock {
122 // KMP_LOCK_FREE(tas) => unlocked; locked: (gtid+1) of owning thread
123 #if defined(__BYTE_ORDER__) && (__BYTE_ORDER__ == __ORDER_BIG_ENDIAN__) && \
124 __LP64__
125 // Flip the ordering of the high and low 32-bit member to be consistent
126 // with the memory layout of the address in 64-bit big-endian.
127 kmp_int32 depth_locked; // depth locked, for nested locks only
128 std::atomic<kmp_int32> poll;
129 #else
130 std::atomic<kmp_int32> poll;
131 kmp_int32 depth_locked; // depth locked, for nested locks only
132 #endif
133 };
134
135 typedef struct kmp_base_tas_lock kmp_base_tas_lock_t;
136
137 union kmp_tas_lock {
138 kmp_base_tas_lock_t lk;
139 kmp_lock_pool_t pool; // make certain struct is large enough
140 double lk_align; // use worst case alignment; no cache line padding
141 };
142
143 typedef union kmp_tas_lock kmp_tas_lock_t;
144
145 // Static initializer for test and set lock variables. Usage:
146 // kmp_tas_lock_t xlock = KMP_TAS_LOCK_INITIALIZER( xlock );
147 #define KMP_TAS_LOCK_INITIALIZER(lock) \
148 { \
149 { KMP_LOCK_FREE(tas), 0 } \
150 }
151
152 extern int __kmp_acquire_tas_lock(kmp_tas_lock_t *lck, kmp_int32 gtid);
153 extern int __kmp_test_tas_lock(kmp_tas_lock_t *lck, kmp_int32 gtid);
154 extern int __kmp_release_tas_lock(kmp_tas_lock_t *lck, kmp_int32 gtid);
155 extern void __kmp_init_tas_lock(kmp_tas_lock_t *lck);
156 extern void __kmp_destroy_tas_lock(kmp_tas_lock_t *lck);
157
158 extern int __kmp_acquire_nested_tas_lock(kmp_tas_lock_t *lck, kmp_int32 gtid);
159 extern int __kmp_test_nested_tas_lock(kmp_tas_lock_t *lck, kmp_int32 gtid);
160 extern int __kmp_release_nested_tas_lock(kmp_tas_lock_t *lck, kmp_int32 gtid);
161 extern void __kmp_init_nested_tas_lock(kmp_tas_lock_t *lck);
162 extern void __kmp_destroy_nested_tas_lock(kmp_tas_lock_t *lck);
163
164 #define KMP_LOCK_RELEASED 1
165 #define KMP_LOCK_STILL_HELD 0
166 #define KMP_LOCK_ACQUIRED_FIRST 1
167 #define KMP_LOCK_ACQUIRED_NEXT 0
168 #ifndef KMP_USE_FUTEX
169 #define KMP_USE_FUTEX \
170 (KMP_OS_LINUX && \
171 (KMP_ARCH_X86 || KMP_ARCH_X86_64 || KMP_ARCH_ARM || KMP_ARCH_AARCH64))
172 #endif
173 #if KMP_USE_FUTEX
174
175 // ----------------------------------------------------------------------------
176 // futex locks. futex locks are only available on Linux* OS.
177 //
178 // Like non-nested test and set lock, non-nested futex locks use the memory
179 // allocated by the compiler for the lock, rather than a pointer to it.
180 //
181 // Information normally available to the tools, such as lock location, lock
182 // usage (normal lock vs. critical section), etc. is not available with test and
183 // set locks. With non-nested futex locks, the lock owner is not even available.
184 // ----------------------------------------------------------------------------
185
186 struct kmp_base_futex_lock {
187 volatile kmp_int32 poll; // KMP_LOCK_FREE(futex) => unlocked
188 // 2*(gtid+1) of owning thread, 0 if unlocked
189 // locked: (gtid+1) of owning thread
190 kmp_int32 depth_locked; // depth locked, for nested locks only
191 };
192
193 typedef struct kmp_base_futex_lock kmp_base_futex_lock_t;
194
195 union kmp_futex_lock {
196 kmp_base_futex_lock_t lk;
197 kmp_lock_pool_t pool; // make certain struct is large enough
198 double lk_align; // use worst case alignment
199 // no cache line padding
200 };
201
202 typedef union kmp_futex_lock kmp_futex_lock_t;
203
204 // Static initializer for futex lock variables. Usage:
205 // kmp_futex_lock_t xlock = KMP_FUTEX_LOCK_INITIALIZER( xlock );
206 #define KMP_FUTEX_LOCK_INITIALIZER(lock) \
207 { \
208 { KMP_LOCK_FREE(futex), 0 } \
209 }
210
211 extern int __kmp_acquire_futex_lock(kmp_futex_lock_t *lck, kmp_int32 gtid);
212 extern int __kmp_test_futex_lock(kmp_futex_lock_t *lck, kmp_int32 gtid);
213 extern int __kmp_release_futex_lock(kmp_futex_lock_t *lck, kmp_int32 gtid);
214 extern void __kmp_init_futex_lock(kmp_futex_lock_t *lck);
215 extern void __kmp_destroy_futex_lock(kmp_futex_lock_t *lck);
216
217 extern int __kmp_acquire_nested_futex_lock(kmp_futex_lock_t *lck,
218 kmp_int32 gtid);
219 extern int __kmp_test_nested_futex_lock(kmp_futex_lock_t *lck, kmp_int32 gtid);
220 extern int __kmp_release_nested_futex_lock(kmp_futex_lock_t *lck,
221 kmp_int32 gtid);
222 extern void __kmp_init_nested_futex_lock(kmp_futex_lock_t *lck);
223 extern void __kmp_destroy_nested_futex_lock(kmp_futex_lock_t *lck);
224
225 #endif // KMP_USE_FUTEX
226
227 // ----------------------------------------------------------------------------
228 // Ticket locks.
229
230 #ifdef __cplusplus
231
232 #ifdef _MSC_VER
233 // MSVC won't allow use of std::atomic<> in a union since it has non-trivial
234 // copy constructor.
235
236 struct kmp_base_ticket_lock {
237 // `initialized' must be the first entry in the lock data structure!
238 std::atomic_bool initialized;
239 volatile union kmp_ticket_lock *self; // points to the lock union
240 ident_t const *location; // Source code location of omp_init_lock().
241 std::atomic_uint
242 next_ticket; // ticket number to give to next thread which acquires
243 std::atomic_uint now_serving; // ticket number for thread which holds the lock
244 std::atomic_int owner_id; // (gtid+1) of owning thread, 0 if unlocked
245 std::atomic_int depth_locked; // depth locked, for nested locks only
246 kmp_lock_flags_t flags; // lock specifics, e.g. critical section lock
247 };
248 #else
249 struct kmp_base_ticket_lock {
250 // `initialized' must be the first entry in the lock data structure!
251 std::atomic<bool> initialized;
252 volatile union kmp_ticket_lock *self; // points to the lock union
253 ident_t const *location; // Source code location of omp_init_lock().
254 std::atomic<unsigned>
255 next_ticket; // ticket number to give to next thread which acquires
256 std::atomic<unsigned>
257 now_serving; // ticket number for thread which holds the lock
258 std::atomic<int> owner_id; // (gtid+1) of owning thread, 0 if unlocked
259 std::atomic<int> depth_locked; // depth locked, for nested locks only
260 kmp_lock_flags_t flags; // lock specifics, e.g. critical section lock
261 };
262 #endif
263
264 #else // __cplusplus
265
266 struct kmp_base_ticket_lock;
267
268 #endif // !__cplusplus
269
270 typedef struct kmp_base_ticket_lock kmp_base_ticket_lock_t;
271
272 union KMP_ALIGN_CACHE kmp_ticket_lock {
273 kmp_base_ticket_lock_t
274 lk; // This field must be first to allow static initializing.
275 kmp_lock_pool_t pool;
276 double lk_align; // use worst case alignment
277 char lk_pad[KMP_PAD(kmp_base_ticket_lock_t, CACHE_LINE)];
278 };
279
280 typedef union kmp_ticket_lock kmp_ticket_lock_t;
281
282 // Static initializer for simple ticket lock variables. Usage:
283 // kmp_ticket_lock_t xlock = KMP_TICKET_LOCK_INITIALIZER( xlock );
284 // Note the macro argument. It is important to make var properly initialized.
285 #define KMP_TICKET_LOCK_INITIALIZER(lock) \
286 { \
287 { true, &(lock), NULL, 0U, 0U, 0, -1 } \
288 }
289
290 extern int __kmp_acquire_ticket_lock(kmp_ticket_lock_t *lck, kmp_int32 gtid);
291 extern int __kmp_test_ticket_lock(kmp_ticket_lock_t *lck, kmp_int32 gtid);
292 extern int __kmp_test_ticket_lock_with_cheks(kmp_ticket_lock_t *lck,
293 kmp_int32 gtid);
294 extern int __kmp_release_ticket_lock(kmp_ticket_lock_t *lck, kmp_int32 gtid);
295 extern void __kmp_init_ticket_lock(kmp_ticket_lock_t *lck);
296 extern void __kmp_destroy_ticket_lock(kmp_ticket_lock_t *lck);
297
298 extern int __kmp_acquire_nested_ticket_lock(kmp_ticket_lock_t *lck,
299 kmp_int32 gtid);
300 extern int __kmp_test_nested_ticket_lock(kmp_ticket_lock_t *lck,
301 kmp_int32 gtid);
302 extern int __kmp_release_nested_ticket_lock(kmp_ticket_lock_t *lck,
303 kmp_int32 gtid);
304 extern void __kmp_init_nested_ticket_lock(kmp_ticket_lock_t *lck);
305 extern void __kmp_destroy_nested_ticket_lock(kmp_ticket_lock_t *lck);
306
307 // ----------------------------------------------------------------------------
308 // Queuing locks.
309
310 #if KMP_USE_ADAPTIVE_LOCKS
311
312 struct kmp_adaptive_lock_info;
313
314 typedef struct kmp_adaptive_lock_info kmp_adaptive_lock_info_t;
315
316 #if KMP_DEBUG_ADAPTIVE_LOCKS
317
318 struct kmp_adaptive_lock_statistics {
319 /* So we can get stats from locks that haven't been destroyed. */
320 kmp_adaptive_lock_info_t *next;
321 kmp_adaptive_lock_info_t *prev;
322
323 /* Other statistics */
324 kmp_uint32 successfulSpeculations;
325 kmp_uint32 hardFailedSpeculations;
326 kmp_uint32 softFailedSpeculations;
327 kmp_uint32 nonSpeculativeAcquires;
328 kmp_uint32 nonSpeculativeAcquireAttempts;
329 kmp_uint32 lemmingYields;
330 };
331
332 typedef struct kmp_adaptive_lock_statistics kmp_adaptive_lock_statistics_t;
333
334 extern void __kmp_print_speculative_stats();
335 extern void __kmp_init_speculative_stats();
336
337 #endif // KMP_DEBUG_ADAPTIVE_LOCKS
338
339 struct kmp_adaptive_lock_info {
340 /* Values used for adaptivity.
341 Although these are accessed from multiple threads we don't access them
342 atomically, because if we miss updates it probably doesn't matter much. (It
343 just affects our decision about whether to try speculation on the lock). */
344 kmp_uint32 volatile badness;
345 kmp_uint32 volatile acquire_attempts;
346 /* Parameters of the lock. */
347 kmp_uint32 max_badness;
348 kmp_uint32 max_soft_retries;
349
350 #if KMP_DEBUG_ADAPTIVE_LOCKS
351 kmp_adaptive_lock_statistics_t volatile stats;
352 #endif
353 };
354
355 #endif // KMP_USE_ADAPTIVE_LOCKS
356
357 struct kmp_base_queuing_lock {
358
359 // `initialized' must be the first entry in the lock data structure!
360 volatile union kmp_queuing_lock
361 *initialized; // Points to the lock union if in initialized state.
362
363 ident_t const *location; // Source code location of omp_init_lock().
364
365 KMP_ALIGN(8) // tail_id must be 8-byte aligned!
366
367 volatile kmp_int32
368 tail_id; // (gtid+1) of thread at tail of wait queue, 0 if empty
369 // Must be no padding here since head/tail used in 8-byte CAS
370 volatile kmp_int32
371 head_id; // (gtid+1) of thread at head of wait queue, 0 if empty
372 // Decl order assumes little endian
373 // bakery-style lock
374 volatile kmp_uint32
375 next_ticket; // ticket number to give to next thread which acquires
376 volatile kmp_uint32
377 now_serving; // ticket number for thread which holds the lock
378 volatile kmp_int32 owner_id; // (gtid+1) of owning thread, 0 if unlocked
379 kmp_int32 depth_locked; // depth locked, for nested locks only
380
381 kmp_lock_flags_t flags; // lock specifics, e.g. critical section lock
382 };
383
384 typedef struct kmp_base_queuing_lock kmp_base_queuing_lock_t;
385
386 KMP_BUILD_ASSERT(offsetof(kmp_base_queuing_lock_t, tail_id) % 8 == 0);
387
388 union KMP_ALIGN_CACHE kmp_queuing_lock {
389 kmp_base_queuing_lock_t
390 lk; // This field must be first to allow static initializing.
391 kmp_lock_pool_t pool;
392 double lk_align; // use worst case alignment
393 char lk_pad[KMP_PAD(kmp_base_queuing_lock_t, CACHE_LINE)];
394 };
395
396 typedef union kmp_queuing_lock kmp_queuing_lock_t;
397
398 extern int __kmp_acquire_queuing_lock(kmp_queuing_lock_t *lck, kmp_int32 gtid);
399 extern int __kmp_test_queuing_lock(kmp_queuing_lock_t *lck, kmp_int32 gtid);
400 extern int __kmp_release_queuing_lock(kmp_queuing_lock_t *lck, kmp_int32 gtid);
401 extern void __kmp_init_queuing_lock(kmp_queuing_lock_t *lck);
402 extern void __kmp_destroy_queuing_lock(kmp_queuing_lock_t *lck);
403
404 extern int __kmp_acquire_nested_queuing_lock(kmp_queuing_lock_t *lck,
405 kmp_int32 gtid);
406 extern int __kmp_test_nested_queuing_lock(kmp_queuing_lock_t *lck,
407 kmp_int32 gtid);
408 extern int __kmp_release_nested_queuing_lock(kmp_queuing_lock_t *lck,
409 kmp_int32 gtid);
410 extern void __kmp_init_nested_queuing_lock(kmp_queuing_lock_t *lck);
411 extern void __kmp_destroy_nested_queuing_lock(kmp_queuing_lock_t *lck);
412
413 #if KMP_USE_ADAPTIVE_LOCKS
414
415 // ----------------------------------------------------------------------------
416 // Adaptive locks.
417 struct kmp_base_adaptive_lock {
418 kmp_base_queuing_lock qlk;
419 KMP_ALIGN(CACHE_LINE)
420 kmp_adaptive_lock_info_t
421 adaptive; // Information for the speculative adaptive lock
422 };
423
424 typedef struct kmp_base_adaptive_lock kmp_base_adaptive_lock_t;
425
426 union KMP_ALIGN_CACHE kmp_adaptive_lock {
427 kmp_base_adaptive_lock_t lk;
428 kmp_lock_pool_t pool;
429 double lk_align;
430 char lk_pad[KMP_PAD(kmp_base_adaptive_lock_t, CACHE_LINE)];
431 };
432 typedef union kmp_adaptive_lock kmp_adaptive_lock_t;
433
434 #define GET_QLK_PTR(l) ((kmp_queuing_lock_t *)&(l)->lk.qlk)
435
436 #endif // KMP_USE_ADAPTIVE_LOCKS
437
438 // ----------------------------------------------------------------------------
439 // DRDPA ticket locks.
440 struct kmp_base_drdpa_lock {
441 // All of the fields on the first cache line are only written when
442 // initializing or reconfiguring the lock. These are relatively rare
443 // operations, so data from the first cache line will usually stay resident in
444 // the cache of each thread trying to acquire the lock.
445 //
446 // initialized must be the first entry in the lock data structure!
447 KMP_ALIGN_CACHE
448
449 volatile union kmp_drdpa_lock
450 *initialized; // points to the lock union if in initialized state
451 ident_t const *location; // Source code location of omp_init_lock().
452 std::atomic<std::atomic<kmp_uint64> *> polls;
453 std::atomic<kmp_uint64> mask; // is 2**num_polls-1 for mod op
454 kmp_uint64 cleanup_ticket; // thread with cleanup ticket
455 std::atomic<kmp_uint64> *old_polls; // will deallocate old_polls
456 kmp_uint32 num_polls; // must be power of 2
457
458 // next_ticket it needs to exist in a separate cache line, as it is
459 // invalidated every time a thread takes a new ticket.
460 KMP_ALIGN_CACHE
461
462 std::atomic<kmp_uint64> next_ticket;
463
464 // now_serving is used to store our ticket value while we hold the lock. It
465 // has a slightly different meaning in the DRDPA ticket locks (where it is
466 // written by the acquiring thread) than it does in the simple ticket locks
467 // (where it is written by the releasing thread).
468 //
469 // Since now_serving is only read and written in the critical section,
470 // it is non-volatile, but it needs to exist on a separate cache line,
471 // as it is invalidated at every lock acquire.
472 //
473 // Likewise, the vars used for nested locks (owner_id and depth_locked) are
474 // only written by the thread owning the lock, so they are put in this cache
475 // line. owner_id is read by other threads, so it must be declared volatile.
476 KMP_ALIGN_CACHE
477 kmp_uint64 now_serving; // doesn't have to be volatile
478 volatile kmp_uint32 owner_id; // (gtid+1) of owning thread, 0 if unlocked
479 kmp_int32 depth_locked; // depth locked
480 kmp_lock_flags_t flags; // lock specifics, e.g. critical section lock
481 };
482
483 typedef struct kmp_base_drdpa_lock kmp_base_drdpa_lock_t;
484
485 union KMP_ALIGN_CACHE kmp_drdpa_lock {
486 kmp_base_drdpa_lock_t
487 lk; // This field must be first to allow static initializing. */
488 kmp_lock_pool_t pool;
489 double lk_align; // use worst case alignment
490 char lk_pad[KMP_PAD(kmp_base_drdpa_lock_t, CACHE_LINE)];
491 };
492
493 typedef union kmp_drdpa_lock kmp_drdpa_lock_t;
494
495 extern int __kmp_acquire_drdpa_lock(kmp_drdpa_lock_t *lck, kmp_int32 gtid);
496 extern int __kmp_test_drdpa_lock(kmp_drdpa_lock_t *lck, kmp_int32 gtid);
497 extern int __kmp_release_drdpa_lock(kmp_drdpa_lock_t *lck, kmp_int32 gtid);
498 extern void __kmp_init_drdpa_lock(kmp_drdpa_lock_t *lck);
499 extern void __kmp_destroy_drdpa_lock(kmp_drdpa_lock_t *lck);
500
501 extern int __kmp_acquire_nested_drdpa_lock(kmp_drdpa_lock_t *lck,
502 kmp_int32 gtid);
503 extern int __kmp_test_nested_drdpa_lock(kmp_drdpa_lock_t *lck, kmp_int32 gtid);
504 extern int __kmp_release_nested_drdpa_lock(kmp_drdpa_lock_t *lck,
505 kmp_int32 gtid);
506 extern void __kmp_init_nested_drdpa_lock(kmp_drdpa_lock_t *lck);
507 extern void __kmp_destroy_nested_drdpa_lock(kmp_drdpa_lock_t *lck);
508
509 // ============================================================================
510 // Lock purposes.
511 // ============================================================================
512
513 // Bootstrap locks.
514 //
515 // Bootstrap locks -- very few locks used at library initialization time.
516 // Bootstrap locks are currently implemented as ticket locks.
517 // They could also be implemented as test and set lock, but cannot be
518 // implemented with other lock kinds as they require gtids which are not
519 // available at initialization time.
520
521 typedef kmp_ticket_lock_t kmp_bootstrap_lock_t;
522
523 #define KMP_BOOTSTRAP_LOCK_INITIALIZER(lock) KMP_TICKET_LOCK_INITIALIZER((lock))
524 #define KMP_BOOTSTRAP_LOCK_INIT(lock) \
525 kmp_bootstrap_lock_t lock = KMP_TICKET_LOCK_INITIALIZER(lock)
526
__kmp_acquire_bootstrap_lock(kmp_bootstrap_lock_t * lck)527 static inline int __kmp_acquire_bootstrap_lock(kmp_bootstrap_lock_t *lck) {
528 return __kmp_acquire_ticket_lock(lck, KMP_GTID_DNE);
529 }
530
__kmp_test_bootstrap_lock(kmp_bootstrap_lock_t * lck)531 static inline int __kmp_test_bootstrap_lock(kmp_bootstrap_lock_t *lck) {
532 return __kmp_test_ticket_lock(lck, KMP_GTID_DNE);
533 }
534
__kmp_release_bootstrap_lock(kmp_bootstrap_lock_t * lck)535 static inline void __kmp_release_bootstrap_lock(kmp_bootstrap_lock_t *lck) {
536 __kmp_release_ticket_lock(lck, KMP_GTID_DNE);
537 }
538
__kmp_init_bootstrap_lock(kmp_bootstrap_lock_t * lck)539 static inline void __kmp_init_bootstrap_lock(kmp_bootstrap_lock_t *lck) {
540 __kmp_init_ticket_lock(lck);
541 }
542
__kmp_destroy_bootstrap_lock(kmp_bootstrap_lock_t * lck)543 static inline void __kmp_destroy_bootstrap_lock(kmp_bootstrap_lock_t *lck) {
544 __kmp_destroy_ticket_lock(lck);
545 }
546
547 // Internal RTL locks.
548 //
549 // Internal RTL locks are also implemented as ticket locks, for now.
550 //
551 // FIXME - We should go through and figure out which lock kind works best for
552 // each internal lock, and use the type declaration and function calls for
553 // that explicit lock kind (and get rid of this section).
554
555 typedef kmp_ticket_lock_t kmp_lock_t;
556
557 #define KMP_LOCK_INIT(lock) kmp_lock_t lock = KMP_TICKET_LOCK_INITIALIZER(lock)
558
__kmp_acquire_lock(kmp_lock_t * lck,kmp_int32 gtid)559 static inline int __kmp_acquire_lock(kmp_lock_t *lck, kmp_int32 gtid) {
560 return __kmp_acquire_ticket_lock(lck, gtid);
561 }
562
__kmp_test_lock(kmp_lock_t * lck,kmp_int32 gtid)563 static inline int __kmp_test_lock(kmp_lock_t *lck, kmp_int32 gtid) {
564 return __kmp_test_ticket_lock(lck, gtid);
565 }
566
__kmp_release_lock(kmp_lock_t * lck,kmp_int32 gtid)567 static inline void __kmp_release_lock(kmp_lock_t *lck, kmp_int32 gtid) {
568 __kmp_release_ticket_lock(lck, gtid);
569 }
570
__kmp_init_lock(kmp_lock_t * lck)571 static inline void __kmp_init_lock(kmp_lock_t *lck) {
572 __kmp_init_ticket_lock(lck);
573 }
574
__kmp_destroy_lock(kmp_lock_t * lck)575 static inline void __kmp_destroy_lock(kmp_lock_t *lck) {
576 __kmp_destroy_ticket_lock(lck);
577 }
578
579 // User locks.
580 //
581 // Do not allocate objects of type union kmp_user_lock!!! This will waste space
582 // unless __kmp_user_lock_kind == lk_drdpa. Instead, check the value of
583 // __kmp_user_lock_kind and allocate objects of the type of the appropriate
584 // union member, and cast their addresses to kmp_user_lock_p.
585
586 enum kmp_lock_kind {
587 lk_default = 0,
588 lk_tas,
589 #if KMP_USE_FUTEX
590 lk_futex,
591 #endif
592 #if KMP_USE_DYNAMIC_LOCK && KMP_USE_TSX
593 lk_hle,
594 lk_rtm_queuing,
595 lk_rtm_spin,
596 #endif
597 lk_ticket,
598 lk_queuing,
599 lk_drdpa,
600 #if KMP_USE_ADAPTIVE_LOCKS
601 lk_adaptive
602 #endif // KMP_USE_ADAPTIVE_LOCKS
603 };
604
605 typedef enum kmp_lock_kind kmp_lock_kind_t;
606
607 extern kmp_lock_kind_t __kmp_user_lock_kind;
608
609 union kmp_user_lock {
610 kmp_tas_lock_t tas;
611 #if KMP_USE_FUTEX
612 kmp_futex_lock_t futex;
613 #endif
614 kmp_ticket_lock_t ticket;
615 kmp_queuing_lock_t queuing;
616 kmp_drdpa_lock_t drdpa;
617 #if KMP_USE_ADAPTIVE_LOCKS
618 kmp_adaptive_lock_t adaptive;
619 #endif // KMP_USE_ADAPTIVE_LOCKS
620 kmp_lock_pool_t pool;
621 };
622
623 typedef union kmp_user_lock *kmp_user_lock_p;
624
625 #if !KMP_USE_DYNAMIC_LOCK
626
627 extern size_t __kmp_base_user_lock_size;
628 extern size_t __kmp_user_lock_size;
629
630 extern kmp_int32 (*__kmp_get_user_lock_owner_)(kmp_user_lock_p lck);
631
__kmp_get_user_lock_owner(kmp_user_lock_p lck)632 static inline kmp_int32 __kmp_get_user_lock_owner(kmp_user_lock_p lck) {
633 KMP_DEBUG_ASSERT(__kmp_get_user_lock_owner_ != NULL);
634 return (*__kmp_get_user_lock_owner_)(lck);
635 }
636
637 extern int (*__kmp_acquire_user_lock_with_checks_)(kmp_user_lock_p lck,
638 kmp_int32 gtid);
639
640 #if KMP_OS_LINUX && \
641 (KMP_ARCH_X86 || KMP_ARCH_X86_64 || KMP_ARCH_ARM || KMP_ARCH_AARCH64)
642
643 #define __kmp_acquire_user_lock_with_checks(lck, gtid) \
644 if (__kmp_user_lock_kind == lk_tas) { \
645 if (__kmp_env_consistency_check) { \
646 char const *const func = "omp_set_lock"; \
647 if ((sizeof(kmp_tas_lock_t) <= OMP_LOCK_T_SIZE) && \
648 lck->tas.lk.depth_locked != -1) { \
649 KMP_FATAL(LockNestableUsedAsSimple, func); \
650 } \
651 if ((gtid >= 0) && (lck->tas.lk.poll - 1 == gtid)) { \
652 KMP_FATAL(LockIsAlreadyOwned, func); \
653 } \
654 } \
655 if (lck->tas.lk.poll != 0 || \
656 !__kmp_atomic_compare_store_acq(&lck->tas.lk.poll, 0, gtid + 1)) { \
657 kmp_uint32 spins; \
658 kmp_uint64 time; \
659 KMP_FSYNC_PREPARE(lck); \
660 KMP_INIT_YIELD(spins); \
661 KMP_INIT_BACKOFF(time); \
662 do { \
663 KMP_YIELD_OVERSUB_ELSE_SPIN(spins, time); \
664 } while ( \
665 lck->tas.lk.poll != 0 || \
666 !__kmp_atomic_compare_store_acq(&lck->tas.lk.poll, 0, gtid + 1)); \
667 } \
668 KMP_FSYNC_ACQUIRED(lck); \
669 } else { \
670 KMP_DEBUG_ASSERT(__kmp_acquire_user_lock_with_checks_ != NULL); \
671 (*__kmp_acquire_user_lock_with_checks_)(lck, gtid); \
672 }
673
674 #else
__kmp_acquire_user_lock_with_checks(kmp_user_lock_p lck,kmp_int32 gtid)675 static inline int __kmp_acquire_user_lock_with_checks(kmp_user_lock_p lck,
676 kmp_int32 gtid) {
677 KMP_DEBUG_ASSERT(__kmp_acquire_user_lock_with_checks_ != NULL);
678 return (*__kmp_acquire_user_lock_with_checks_)(lck, gtid);
679 }
680 #endif
681
682 extern int (*__kmp_test_user_lock_with_checks_)(kmp_user_lock_p lck,
683 kmp_int32 gtid);
684
685 #if KMP_OS_LINUX && \
686 (KMP_ARCH_X86 || KMP_ARCH_X86_64 || KMP_ARCH_ARM || KMP_ARCH_AARCH64)
687
688 #include "kmp_i18n.h" /* AC: KMP_FATAL definition */
689 extern int __kmp_env_consistency_check; /* AC: copy from kmp.h here */
__kmp_test_user_lock_with_checks(kmp_user_lock_p lck,kmp_int32 gtid)690 static inline int __kmp_test_user_lock_with_checks(kmp_user_lock_p lck,
691 kmp_int32 gtid) {
692 if (__kmp_user_lock_kind == lk_tas) {
693 if (__kmp_env_consistency_check) {
694 char const *const func = "omp_test_lock";
695 if ((sizeof(kmp_tas_lock_t) <= OMP_LOCK_T_SIZE) &&
696 lck->tas.lk.depth_locked != -1) {
697 KMP_FATAL(LockNestableUsedAsSimple, func);
698 }
699 }
700 return ((lck->tas.lk.poll == 0) &&
701 __kmp_atomic_compare_store_acq(&lck->tas.lk.poll, 0, gtid + 1));
702 } else {
703 KMP_DEBUG_ASSERT(__kmp_test_user_lock_with_checks_ != NULL);
704 return (*__kmp_test_user_lock_with_checks_)(lck, gtid);
705 }
706 }
707 #else
__kmp_test_user_lock_with_checks(kmp_user_lock_p lck,kmp_int32 gtid)708 static inline int __kmp_test_user_lock_with_checks(kmp_user_lock_p lck,
709 kmp_int32 gtid) {
710 KMP_DEBUG_ASSERT(__kmp_test_user_lock_with_checks_ != NULL);
711 return (*__kmp_test_user_lock_with_checks_)(lck, gtid);
712 }
713 #endif
714
715 extern int (*__kmp_release_user_lock_with_checks_)(kmp_user_lock_p lck,
716 kmp_int32 gtid);
717
__kmp_release_user_lock_with_checks(kmp_user_lock_p lck,kmp_int32 gtid)718 static inline void __kmp_release_user_lock_with_checks(kmp_user_lock_p lck,
719 kmp_int32 gtid) {
720 KMP_DEBUG_ASSERT(__kmp_release_user_lock_with_checks_ != NULL);
721 (*__kmp_release_user_lock_with_checks_)(lck, gtid);
722 }
723
724 extern void (*__kmp_init_user_lock_with_checks_)(kmp_user_lock_p lck);
725
__kmp_init_user_lock_with_checks(kmp_user_lock_p lck)726 static inline void __kmp_init_user_lock_with_checks(kmp_user_lock_p lck) {
727 KMP_DEBUG_ASSERT(__kmp_init_user_lock_with_checks_ != NULL);
728 (*__kmp_init_user_lock_with_checks_)(lck);
729 }
730
731 // We need a non-checking version of destroy lock for when the RTL is
732 // doing the cleanup as it can't always tell if the lock is nested or not.
733 extern void (*__kmp_destroy_user_lock_)(kmp_user_lock_p lck);
734
__kmp_destroy_user_lock(kmp_user_lock_p lck)735 static inline void __kmp_destroy_user_lock(kmp_user_lock_p lck) {
736 KMP_DEBUG_ASSERT(__kmp_destroy_user_lock_ != NULL);
737 (*__kmp_destroy_user_lock_)(lck);
738 }
739
740 extern void (*__kmp_destroy_user_lock_with_checks_)(kmp_user_lock_p lck);
741
__kmp_destroy_user_lock_with_checks(kmp_user_lock_p lck)742 static inline void __kmp_destroy_user_lock_with_checks(kmp_user_lock_p lck) {
743 KMP_DEBUG_ASSERT(__kmp_destroy_user_lock_with_checks_ != NULL);
744 (*__kmp_destroy_user_lock_with_checks_)(lck);
745 }
746
747 extern int (*__kmp_acquire_nested_user_lock_with_checks_)(kmp_user_lock_p lck,
748 kmp_int32 gtid);
749
750 #if KMP_OS_LINUX && (KMP_ARCH_X86 || KMP_ARCH_X86_64)
751
752 #define __kmp_acquire_nested_user_lock_with_checks(lck, gtid, depth) \
753 if (__kmp_user_lock_kind == lk_tas) { \
754 if (__kmp_env_consistency_check) { \
755 char const *const func = "omp_set_nest_lock"; \
756 if ((sizeof(kmp_tas_lock_t) <= OMP_NEST_LOCK_T_SIZE) && \
757 lck->tas.lk.depth_locked == -1) { \
758 KMP_FATAL(LockSimpleUsedAsNestable, func); \
759 } \
760 } \
761 if (lck->tas.lk.poll - 1 == gtid) { \
762 lck->tas.lk.depth_locked += 1; \
763 *depth = KMP_LOCK_ACQUIRED_NEXT; \
764 } else { \
765 if ((lck->tas.lk.poll != 0) || \
766 !__kmp_atomic_compare_store_acq(&lck->tas.lk.poll, 0, gtid + 1)) { \
767 kmp_uint32 spins; \
768 kmp_uint64 time; \
769 KMP_FSYNC_PREPARE(lck); \
770 KMP_INIT_YIELD(spins); \
771 KMP_INIT_BACKOFF(time); \
772 do { \
773 KMP_YIELD_OVERSUB_ELSE_SPIN(spins, time); \
774 } while ( \
775 (lck->tas.lk.poll != 0) || \
776 !__kmp_atomic_compare_store_acq(&lck->tas.lk.poll, 0, gtid + 1)); \
777 } \
778 lck->tas.lk.depth_locked = 1; \
779 *depth = KMP_LOCK_ACQUIRED_FIRST; \
780 } \
781 KMP_FSYNC_ACQUIRED(lck); \
782 } else { \
783 KMP_DEBUG_ASSERT(__kmp_acquire_nested_user_lock_with_checks_ != NULL); \
784 *depth = (*__kmp_acquire_nested_user_lock_with_checks_)(lck, gtid); \
785 }
786
787 #else
788 static inline void
__kmp_acquire_nested_user_lock_with_checks(kmp_user_lock_p lck,kmp_int32 gtid,int * depth)789 __kmp_acquire_nested_user_lock_with_checks(kmp_user_lock_p lck, kmp_int32 gtid,
790 int *depth) {
791 KMP_DEBUG_ASSERT(__kmp_acquire_nested_user_lock_with_checks_ != NULL);
792 *depth = (*__kmp_acquire_nested_user_lock_with_checks_)(lck, gtid);
793 }
794 #endif
795
796 extern int (*__kmp_test_nested_user_lock_with_checks_)(kmp_user_lock_p lck,
797 kmp_int32 gtid);
798
799 #if KMP_OS_LINUX && (KMP_ARCH_X86 || KMP_ARCH_X86_64)
__kmp_test_nested_user_lock_with_checks(kmp_user_lock_p lck,kmp_int32 gtid)800 static inline int __kmp_test_nested_user_lock_with_checks(kmp_user_lock_p lck,
801 kmp_int32 gtid) {
802 if (__kmp_user_lock_kind == lk_tas) {
803 int retval;
804 if (__kmp_env_consistency_check) {
805 char const *const func = "omp_test_nest_lock";
806 if ((sizeof(kmp_tas_lock_t) <= OMP_NEST_LOCK_T_SIZE) &&
807 lck->tas.lk.depth_locked == -1) {
808 KMP_FATAL(LockSimpleUsedAsNestable, func);
809 }
810 }
811 KMP_DEBUG_ASSERT(gtid >= 0);
812 if (lck->tas.lk.poll - 1 ==
813 gtid) { /* __kmp_get_tas_lock_owner( lck ) == gtid */
814 return ++lck->tas.lk.depth_locked; /* same owner, depth increased */
815 }
816 retval = ((lck->tas.lk.poll == 0) &&
817 __kmp_atomic_compare_store_acq(&lck->tas.lk.poll, 0, gtid + 1));
818 if (retval) {
819 KMP_MB();
820 lck->tas.lk.depth_locked = 1;
821 }
822 return retval;
823 } else {
824 KMP_DEBUG_ASSERT(__kmp_test_nested_user_lock_with_checks_ != NULL);
825 return (*__kmp_test_nested_user_lock_with_checks_)(lck, gtid);
826 }
827 }
828 #else
__kmp_test_nested_user_lock_with_checks(kmp_user_lock_p lck,kmp_int32 gtid)829 static inline int __kmp_test_nested_user_lock_with_checks(kmp_user_lock_p lck,
830 kmp_int32 gtid) {
831 KMP_DEBUG_ASSERT(__kmp_test_nested_user_lock_with_checks_ != NULL);
832 return (*__kmp_test_nested_user_lock_with_checks_)(lck, gtid);
833 }
834 #endif
835
836 extern int (*__kmp_release_nested_user_lock_with_checks_)(kmp_user_lock_p lck,
837 kmp_int32 gtid);
838
839 static inline int
__kmp_release_nested_user_lock_with_checks(kmp_user_lock_p lck,kmp_int32 gtid)840 __kmp_release_nested_user_lock_with_checks(kmp_user_lock_p lck,
841 kmp_int32 gtid) {
842 KMP_DEBUG_ASSERT(__kmp_release_nested_user_lock_with_checks_ != NULL);
843 return (*__kmp_release_nested_user_lock_with_checks_)(lck, gtid);
844 }
845
846 extern void (*__kmp_init_nested_user_lock_with_checks_)(kmp_user_lock_p lck);
847
848 static inline void
__kmp_init_nested_user_lock_with_checks(kmp_user_lock_p lck)849 __kmp_init_nested_user_lock_with_checks(kmp_user_lock_p lck) {
850 KMP_DEBUG_ASSERT(__kmp_init_nested_user_lock_with_checks_ != NULL);
851 (*__kmp_init_nested_user_lock_with_checks_)(lck);
852 }
853
854 extern void (*__kmp_destroy_nested_user_lock_with_checks_)(kmp_user_lock_p lck);
855
856 static inline void
__kmp_destroy_nested_user_lock_with_checks(kmp_user_lock_p lck)857 __kmp_destroy_nested_user_lock_with_checks(kmp_user_lock_p lck) {
858 KMP_DEBUG_ASSERT(__kmp_destroy_nested_user_lock_with_checks_ != NULL);
859 (*__kmp_destroy_nested_user_lock_with_checks_)(lck);
860 }
861
862 // user lock functions which do not necessarily exist for all lock kinds.
863 //
864 // The "set" functions usually have wrapper routines that check for a NULL set
865 // function pointer and call it if non-NULL.
866 //
867 // In some cases, it makes sense to have a "get" wrapper function check for a
868 // NULL get function pointer and return NULL / invalid value / error code if
869 // the function pointer is NULL.
870 //
871 // In other cases, the calling code really should differentiate between an
872 // unimplemented function and one that is implemented but returning NULL /
873 // invalid value. If this is the case, no get function wrapper exists.
874
875 extern int (*__kmp_is_user_lock_initialized_)(kmp_user_lock_p lck);
876
877 // no set function; fields set during local allocation
878
879 extern const ident_t *(*__kmp_get_user_lock_location_)(kmp_user_lock_p lck);
880
__kmp_get_user_lock_location(kmp_user_lock_p lck)881 static inline const ident_t *__kmp_get_user_lock_location(kmp_user_lock_p lck) {
882 if (__kmp_get_user_lock_location_ != NULL) {
883 return (*__kmp_get_user_lock_location_)(lck);
884 } else {
885 return NULL;
886 }
887 }
888
889 extern void (*__kmp_set_user_lock_location_)(kmp_user_lock_p lck,
890 const ident_t *loc);
891
__kmp_set_user_lock_location(kmp_user_lock_p lck,const ident_t * loc)892 static inline void __kmp_set_user_lock_location(kmp_user_lock_p lck,
893 const ident_t *loc) {
894 if (__kmp_set_user_lock_location_ != NULL) {
895 (*__kmp_set_user_lock_location_)(lck, loc);
896 }
897 }
898
899 extern kmp_lock_flags_t (*__kmp_get_user_lock_flags_)(kmp_user_lock_p lck);
900
901 extern void (*__kmp_set_user_lock_flags_)(kmp_user_lock_p lck,
902 kmp_lock_flags_t flags);
903
__kmp_set_user_lock_flags(kmp_user_lock_p lck,kmp_lock_flags_t flags)904 static inline void __kmp_set_user_lock_flags(kmp_user_lock_p lck,
905 kmp_lock_flags_t flags) {
906 if (__kmp_set_user_lock_flags_ != NULL) {
907 (*__kmp_set_user_lock_flags_)(lck, flags);
908 }
909 }
910
911 // The function which sets up all of the vtbl pointers for kmp_user_lock_t.
912 extern void __kmp_set_user_lock_vptrs(kmp_lock_kind_t user_lock_kind);
913
914 // Macros for binding user lock functions.
915 #define KMP_BIND_USER_LOCK_TEMPLATE(nest, kind, suffix) \
916 { \
917 __kmp_acquire##nest##user_lock_with_checks_ = (int (*)( \
918 kmp_user_lock_p, kmp_int32))__kmp_acquire##nest##kind##_##suffix; \
919 __kmp_release##nest##user_lock_with_checks_ = (int (*)( \
920 kmp_user_lock_p, kmp_int32))__kmp_release##nest##kind##_##suffix; \
921 __kmp_test##nest##user_lock_with_checks_ = (int (*)( \
922 kmp_user_lock_p, kmp_int32))__kmp_test##nest##kind##_##suffix; \
923 __kmp_init##nest##user_lock_with_checks_ = \
924 (void (*)(kmp_user_lock_p))__kmp_init##nest##kind##_##suffix; \
925 __kmp_destroy##nest##user_lock_with_checks_ = \
926 (void (*)(kmp_user_lock_p))__kmp_destroy##nest##kind##_##suffix; \
927 }
928
929 #define KMP_BIND_USER_LOCK(kind) KMP_BIND_USER_LOCK_TEMPLATE(_, kind, lock)
930 #define KMP_BIND_USER_LOCK_WITH_CHECKS(kind) \
931 KMP_BIND_USER_LOCK_TEMPLATE(_, kind, lock_with_checks)
932 #define KMP_BIND_NESTED_USER_LOCK(kind) \
933 KMP_BIND_USER_LOCK_TEMPLATE(_nested_, kind, lock)
934 #define KMP_BIND_NESTED_USER_LOCK_WITH_CHECKS(kind) \
935 KMP_BIND_USER_LOCK_TEMPLATE(_nested_, kind, lock_with_checks)
936
937 // User lock table & lock allocation
938 /* On 64-bit Linux* OS (and OS X*) GNU compiler allocates only 4 bytems memory
939 for lock variable, which is not enough to store a pointer, so we have to use
940 lock indexes instead of pointers and maintain lock table to map indexes to
941 pointers.
942
943
944 Note: The first element of the table is not a pointer to lock! It is a
945 pointer to previously allocated table (or NULL if it is the first table).
946
947 Usage:
948
949 if ( OMP_LOCK_T_SIZE < sizeof( <lock> ) ) { // or OMP_NEST_LOCK_T_SIZE
950 Lock table is fully utilized. User locks are indexes, so table is used on
951 user lock operation.
952 Note: it may be the case (lin_32) that we don't need to use a lock
953 table for regular locks, but do need the table for nested locks.
954 }
955 else {
956 Lock table initialized but not actually used.
957 }
958 */
959
960 struct kmp_lock_table {
961 kmp_lock_index_t used; // Number of used elements
962 kmp_lock_index_t allocated; // Number of allocated elements
963 kmp_user_lock_p *table; // Lock table.
964 };
965
966 typedef struct kmp_lock_table kmp_lock_table_t;
967
968 extern kmp_lock_table_t __kmp_user_lock_table;
969 extern kmp_user_lock_p __kmp_lock_pool;
970
971 struct kmp_block_of_locks {
972 struct kmp_block_of_locks *next_block;
973 void *locks;
974 };
975
976 typedef struct kmp_block_of_locks kmp_block_of_locks_t;
977
978 extern kmp_block_of_locks_t *__kmp_lock_blocks;
979 extern int __kmp_num_locks_in_block;
980
981 extern kmp_user_lock_p __kmp_user_lock_allocate(void **user_lock,
982 kmp_int32 gtid,
983 kmp_lock_flags_t flags);
984 extern void __kmp_user_lock_free(void **user_lock, kmp_int32 gtid,
985 kmp_user_lock_p lck);
986 extern kmp_user_lock_p __kmp_lookup_user_lock(void **user_lock,
987 char const *func);
988 extern void __kmp_cleanup_user_locks();
989
990 #define KMP_CHECK_USER_LOCK_INIT() \
991 { \
992 if (!TCR_4(__kmp_init_user_locks)) { \
993 __kmp_acquire_bootstrap_lock(&__kmp_initz_lock); \
994 if (!TCR_4(__kmp_init_user_locks)) { \
995 TCW_4(__kmp_init_user_locks, TRUE); \
996 } \
997 __kmp_release_bootstrap_lock(&__kmp_initz_lock); \
998 } \
999 }
1000
1001 #endif // KMP_USE_DYNAMIC_LOCK
1002
1003 #undef KMP_PAD
1004 #undef KMP_GTID_DNE
1005
1006 #if KMP_USE_DYNAMIC_LOCK
1007 // KMP_USE_DYNAMIC_LOCK enables dynamic dispatch of lock functions without
1008 // breaking the current compatibility. Essential functionality of this new code
1009 // is dynamic dispatch, but it also implements (or enables implementation of)
1010 // hinted user lock and critical section which will be part of OMP 4.5 soon.
1011 //
1012 // Lock type can be decided at creation time (i.e., lock initialization), and
1013 // subsequent lock function call on the created lock object requires type
1014 // extraction and call through jump table using the extracted type. This type
1015 // information is stored in two different ways depending on the size of the lock
1016 // object, and we differentiate lock types by this size requirement - direct and
1017 // indirect locks.
1018 //
1019 // Direct locks:
1020 // A direct lock object fits into the space created by the compiler for an
1021 // omp_lock_t object, and TAS/Futex lock falls into this category. We use low
1022 // one byte of the lock object as the storage for the lock type, and appropriate
1023 // bit operation is required to access the data meaningful to the lock
1024 // algorithms. Also, to differentiate direct lock from indirect lock, 1 is
1025 // written to LSB of the lock object. The newly introduced "hle" lock is also a
1026 // direct lock.
1027 //
1028 // Indirect locks:
1029 // An indirect lock object requires more space than the compiler-generated
1030 // space, and it should be allocated from heap. Depending on the size of the
1031 // compiler-generated space for the lock (i.e., size of omp_lock_t), this
1032 // omp_lock_t object stores either the address of the heap-allocated indirect
1033 // lock (void * fits in the object) or an index to the indirect lock table entry
1034 // that holds the address. Ticket/Queuing/DRDPA/Adaptive lock falls into this
1035 // category, and the newly introduced "rtm" lock is also an indirect lock which
1036 // was implemented on top of the Queuing lock. When the omp_lock_t object holds
1037 // an index (not lock address), 0 is written to LSB to differentiate the lock
1038 // from a direct lock, and the remaining part is the actual index to the
1039 // indirect lock table.
1040
1041 #include <stdint.h> // for uintptr_t
1042
1043 // Shortcuts
1044 #define KMP_USE_INLINED_TAS \
1045 (KMP_OS_LINUX && (KMP_ARCH_X86 || KMP_ARCH_X86_64 || KMP_ARCH_ARM)) && 1
1046 #define KMP_USE_INLINED_FUTEX KMP_USE_FUTEX && 0
1047
1048 // List of lock definitions; all nested locks are indirect locks.
1049 // hle lock is xchg lock prefixed with XACQUIRE/XRELEASE.
1050 // All nested locks are indirect lock types.
1051 #if KMP_USE_TSX
1052 #if KMP_USE_FUTEX
1053 #define KMP_FOREACH_D_LOCK(m, a) m(tas, a) m(futex, a) m(hle, a) m(rtm_spin, a)
1054 #define KMP_FOREACH_I_LOCK(m, a) \
1055 m(ticket, a) m(queuing, a) m(adaptive, a) m(drdpa, a) m(rtm_queuing, a) \
1056 m(nested_tas, a) m(nested_futex, a) m(nested_ticket, a) \
1057 m(nested_queuing, a) m(nested_drdpa, a)
1058 #else
1059 #define KMP_FOREACH_D_LOCK(m, a) m(tas, a) m(hle, a) m(rtm_spin, a)
1060 #define KMP_FOREACH_I_LOCK(m, a) \
1061 m(ticket, a) m(queuing, a) m(adaptive, a) m(drdpa, a) m(rtm_queuing, a) \
1062 m(nested_tas, a) m(nested_ticket, a) m(nested_queuing, a) \
1063 m(nested_drdpa, a)
1064 #endif // KMP_USE_FUTEX
1065 #define KMP_LAST_D_LOCK lockseq_rtm_spin
1066 #else
1067 #if KMP_USE_FUTEX
1068 #define KMP_FOREACH_D_LOCK(m, a) m(tas, a) m(futex, a)
1069 #define KMP_FOREACH_I_LOCK(m, a) \
1070 m(ticket, a) m(queuing, a) m(drdpa, a) m(nested_tas, a) m(nested_futex, a) \
1071 m(nested_ticket, a) m(nested_queuing, a) m(nested_drdpa, a)
1072 #define KMP_LAST_D_LOCK lockseq_futex
1073 #else
1074 #define KMP_FOREACH_D_LOCK(m, a) m(tas, a)
1075 #define KMP_FOREACH_I_LOCK(m, a) \
1076 m(ticket, a) m(queuing, a) m(drdpa, a) m(nested_tas, a) m(nested_ticket, a) \
1077 m(nested_queuing, a) m(nested_drdpa, a)
1078 #define KMP_LAST_D_LOCK lockseq_tas
1079 #endif // KMP_USE_FUTEX
1080 #endif // KMP_USE_TSX
1081
1082 // Information used in dynamic dispatch
1083 #define KMP_LOCK_SHIFT \
1084 8 // number of low bits to be used as tag for direct locks
1085 #define KMP_FIRST_D_LOCK lockseq_tas
1086 #define KMP_FIRST_I_LOCK lockseq_ticket
1087 #define KMP_LAST_I_LOCK lockseq_nested_drdpa
1088 #define KMP_NUM_I_LOCKS \
1089 (locktag_nested_drdpa + 1) // number of indirect lock types
1090
1091 // Base type for dynamic locks.
1092 typedef kmp_uint32 kmp_dyna_lock_t;
1093
1094 // Lock sequence that enumerates all lock kinds. Always make this enumeration
1095 // consistent with kmp_lockseq_t in the include directory.
1096 typedef enum {
1097 lockseq_indirect = 0,
1098 #define expand_seq(l, a) lockseq_##l,
1099 KMP_FOREACH_D_LOCK(expand_seq, 0) KMP_FOREACH_I_LOCK(expand_seq, 0)
1100 #undef expand_seq
1101 } kmp_dyna_lockseq_t;
1102
1103 // Enumerates indirect lock tags.
1104 typedef enum {
1105 #define expand_tag(l, a) locktag_##l,
1106 KMP_FOREACH_I_LOCK(expand_tag, 0)
1107 #undef expand_tag
1108 } kmp_indirect_locktag_t;
1109
1110 // Utility macros that extract information from lock sequences.
1111 #define KMP_IS_D_LOCK(seq) \
1112 ((seq) >= KMP_FIRST_D_LOCK && (seq) <= KMP_LAST_D_LOCK)
1113 #define KMP_IS_I_LOCK(seq) \
1114 ((seq) >= KMP_FIRST_I_LOCK && (seq) <= KMP_LAST_I_LOCK)
1115 #define KMP_GET_I_TAG(seq) (kmp_indirect_locktag_t)((seq)-KMP_FIRST_I_LOCK)
1116 #define KMP_GET_D_TAG(seq) ((seq) << 1 | 1)
1117
1118 // Enumerates direct lock tags starting from indirect tag.
1119 typedef enum {
1120 #define expand_tag(l, a) locktag_##l = KMP_GET_D_TAG(lockseq_##l),
1121 KMP_FOREACH_D_LOCK(expand_tag, 0)
1122 #undef expand_tag
1123 } kmp_direct_locktag_t;
1124
1125 // Indirect lock type
1126 typedef struct {
1127 kmp_user_lock_p lock;
1128 kmp_indirect_locktag_t type;
1129 } kmp_indirect_lock_t;
1130
1131 // Function tables for direct locks. Set/unset/test differentiate functions
1132 // with/without consistency checking.
1133 extern void (*__kmp_direct_init[])(kmp_dyna_lock_t *, kmp_dyna_lockseq_t);
1134 extern void (**__kmp_direct_destroy)(kmp_dyna_lock_t *);
1135 extern int (**__kmp_direct_set)(kmp_dyna_lock_t *, kmp_int32);
1136 extern int (**__kmp_direct_unset)(kmp_dyna_lock_t *, kmp_int32);
1137 extern int (**__kmp_direct_test)(kmp_dyna_lock_t *, kmp_int32);
1138
1139 // Function tables for indirect locks. Set/unset/test differentiate functions
1140 // with/without consistency checking.
1141 extern void (*__kmp_indirect_init[])(kmp_user_lock_p);
1142 extern void (**__kmp_indirect_destroy)(kmp_user_lock_p);
1143 extern int (**__kmp_indirect_set)(kmp_user_lock_p, kmp_int32);
1144 extern int (**__kmp_indirect_unset)(kmp_user_lock_p, kmp_int32);
1145 extern int (**__kmp_indirect_test)(kmp_user_lock_p, kmp_int32);
1146
1147 // Extracts direct lock tag from a user lock pointer
1148 #define KMP_EXTRACT_D_TAG(l) \
1149 ((kmp_dyna_lock_t)((kmp_base_tas_lock_t *)(l))->poll & \
1150 ((1 << KMP_LOCK_SHIFT) - 1) & \
1151 -((kmp_dyna_lock_t)((kmp_tas_lock_t *)(l))->lk.poll & 1))
1152
1153 // Extracts indirect lock index from a user lock pointer
1154 #define KMP_EXTRACT_I_INDEX(l) \
1155 ((kmp_lock_index_t)((kmp_base_tas_lock_t *)(l))->poll >> 1)
1156
1157 // Returns function pointer to the direct lock function with l (kmp_dyna_lock_t
1158 // *) and op (operation type).
1159 #define KMP_D_LOCK_FUNC(l, op) __kmp_direct_##op[KMP_EXTRACT_D_TAG(l)]
1160
1161 // Returns function pointer to the indirect lock function with l
1162 // (kmp_indirect_lock_t *) and op (operation type).
1163 #define KMP_I_LOCK_FUNC(l, op) \
1164 __kmp_indirect_##op[((kmp_indirect_lock_t *)(l))->type]
1165
1166 // Initializes a direct lock with the given lock pointer and lock sequence.
1167 #define KMP_INIT_D_LOCK(l, seq) \
1168 __kmp_direct_init[KMP_GET_D_TAG(seq)]((kmp_dyna_lock_t *)l, seq)
1169
1170 // Initializes an indirect lock with the given lock pointer and lock sequence.
1171 #define KMP_INIT_I_LOCK(l, seq) \
1172 __kmp_direct_init[0]((kmp_dyna_lock_t *)(l), seq)
1173
1174 // Returns "free" lock value for the given lock type.
1175 #define KMP_LOCK_FREE(type) (locktag_##type)
1176
1177 // Returns "busy" lock value for the given lock teyp.
1178 #define KMP_LOCK_BUSY(v, type) ((v) << KMP_LOCK_SHIFT | locktag_##type)
1179
1180 // Returns lock value after removing (shifting) lock tag.
1181 #define KMP_LOCK_STRIP(v) ((v) >> KMP_LOCK_SHIFT)
1182
1183 // Initializes global states and data structures for managing dynamic user
1184 // locks.
1185 extern void __kmp_init_dynamic_user_locks();
1186
1187 // Allocates and returns an indirect lock with the given indirect lock tag.
1188 extern kmp_indirect_lock_t *
1189 __kmp_allocate_indirect_lock(void **, kmp_int32, kmp_indirect_locktag_t);
1190
1191 // Cleans up global states and data structures for managing dynamic user locks.
1192 extern void __kmp_cleanup_indirect_user_locks();
1193
1194 // Default user lock sequence when not using hinted locks.
1195 extern kmp_dyna_lockseq_t __kmp_user_lock_seq;
1196
1197 // Jump table for "set lock location", available only for indirect locks.
1198 extern void (*__kmp_indirect_set_location[KMP_NUM_I_LOCKS])(kmp_user_lock_p,
1199 const ident_t *);
1200 #define KMP_SET_I_LOCK_LOCATION(lck, loc) \
1201 { \
1202 if (__kmp_indirect_set_location[(lck)->type] != NULL) \
1203 __kmp_indirect_set_location[(lck)->type]((lck)->lock, loc); \
1204 }
1205
1206 // Jump table for "set lock flags", available only for indirect locks.
1207 extern void (*__kmp_indirect_set_flags[KMP_NUM_I_LOCKS])(kmp_user_lock_p,
1208 kmp_lock_flags_t);
1209 #define KMP_SET_I_LOCK_FLAGS(lck, flag) \
1210 { \
1211 if (__kmp_indirect_set_flags[(lck)->type] != NULL) \
1212 __kmp_indirect_set_flags[(lck)->type]((lck)->lock, flag); \
1213 }
1214
1215 // Jump table for "get lock location", available only for indirect locks.
1216 extern const ident_t *(*__kmp_indirect_get_location[KMP_NUM_I_LOCKS])(
1217 kmp_user_lock_p);
1218 #define KMP_GET_I_LOCK_LOCATION(lck) \
1219 (__kmp_indirect_get_location[(lck)->type] != NULL \
1220 ? __kmp_indirect_get_location[(lck)->type]((lck)->lock) \
1221 : NULL)
1222
1223 // Jump table for "get lock flags", available only for indirect locks.
1224 extern kmp_lock_flags_t (*__kmp_indirect_get_flags[KMP_NUM_I_LOCKS])(
1225 kmp_user_lock_p);
1226 #define KMP_GET_I_LOCK_FLAGS(lck) \
1227 (__kmp_indirect_get_flags[(lck)->type] != NULL \
1228 ? __kmp_indirect_get_flags[(lck)->type]((lck)->lock) \
1229 : NULL)
1230
1231 // number of kmp_indirect_lock_t objects to be allocated together
1232 #define KMP_I_LOCK_CHUNK 1024
1233 // Keep at a power of 2 since it is used in multiplication & division
1234 KMP_BUILD_ASSERT(KMP_I_LOCK_CHUNK % 2 == 0);
1235 // number of row entries in the initial lock table
1236 #define KMP_I_LOCK_TABLE_INIT_NROW_PTRS 8
1237
1238 // Lock table for indirect locks.
1239 typedef struct kmp_indirect_lock_table {
1240 kmp_indirect_lock_t **table; // blocks of indirect locks allocated
1241 kmp_uint32 nrow_ptrs; // number *table pointer entries in table
1242 kmp_lock_index_t next; // index to the next lock to be allocated
1243 struct kmp_indirect_lock_table *next_table;
1244 } kmp_indirect_lock_table_t;
1245
1246 extern kmp_indirect_lock_table_t __kmp_i_lock_table;
1247
1248 // Returns the indirect lock associated with the given index.
1249 // Returns nullptr if no lock at given index
__kmp_get_i_lock(kmp_lock_index_t idx)1250 static inline kmp_indirect_lock_t *__kmp_get_i_lock(kmp_lock_index_t idx) {
1251 kmp_indirect_lock_table_t *lock_table = &__kmp_i_lock_table;
1252 while (lock_table) {
1253 kmp_lock_index_t max_locks = lock_table->nrow_ptrs * KMP_I_LOCK_CHUNK;
1254 if (idx < max_locks) {
1255 kmp_lock_index_t row = idx / KMP_I_LOCK_CHUNK;
1256 kmp_lock_index_t col = idx % KMP_I_LOCK_CHUNK;
1257 if (!lock_table->table[row] || idx >= lock_table->next)
1258 break;
1259 return &lock_table->table[row][col];
1260 }
1261 idx -= max_locks;
1262 lock_table = lock_table->next_table;
1263 }
1264 return nullptr;
1265 }
1266
1267 // Number of locks in a lock block, which is fixed to "1" now.
1268 // TODO: No lock block implementation now. If we do support, we need to manage
1269 // lock block data structure for each indirect lock type.
1270 extern int __kmp_num_locks_in_block;
1271
1272 // Fast lock table lookup without consistency checking
1273 #define KMP_LOOKUP_I_LOCK(l) \
1274 ((OMP_LOCK_T_SIZE < sizeof(void *)) \
1275 ? __kmp_get_i_lock(KMP_EXTRACT_I_INDEX(l)) \
1276 : *((kmp_indirect_lock_t **)(l)))
1277
1278 // Used once in kmp_error.cpp
1279 extern kmp_int32 __kmp_get_user_lock_owner(kmp_user_lock_p, kmp_uint32);
1280
1281 #else // KMP_USE_DYNAMIC_LOCK
1282
1283 #define KMP_LOCK_BUSY(v, type) (v)
1284 #define KMP_LOCK_FREE(type) 0
1285 #define KMP_LOCK_STRIP(v) (v)
1286
1287 #endif // KMP_USE_DYNAMIC_LOCK
1288
1289 // data structure for using backoff within spin locks.
1290 typedef struct {
1291 kmp_uint32 step; // current step
1292 kmp_uint32 max_backoff; // upper bound of outer delay loop
1293 kmp_uint32 min_tick; // size of inner delay loop in ticks (machine-dependent)
1294 } kmp_backoff_t;
1295
1296 // Runtime's default backoff parameters
1297 extern kmp_backoff_t __kmp_spin_backoff_params;
1298
1299 // Backoff function
1300 extern void __kmp_spin_backoff(kmp_backoff_t *);
1301
1302 #ifdef __cplusplus
1303 } // extern "C"
1304 #endif // __cplusplus
1305
1306 #endif /* KMP_LOCK_H */
1307