xref: /third_party/mesa3d/src/util/u_thread.h (revision bf215546)
1/**************************************************************************
2 *
3 * Copyright 1999-2006 Brian Paul
4 * Copyright 2008 VMware, Inc.
5 * All Rights Reserved.
6 *
7 * Permission is hereby granted, free of charge, to any person obtaining a
8 * copy of this software and associated documentation files (the "Software"),
9 * to deal in the Software without restriction, including without limitation
10 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
11 * and/or sell copies of the Software, and to permit persons to whom the
12 * Software is furnished to do so, subject to the following conditions:
13 *
14 * The above copyright notice and this permission notice shall be included
15 * in all copies or substantial portions of the Software.
16 *
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
18 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
20 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
21 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
22 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
23 * OTHER DEALINGS IN THE SOFTWARE.
24 *
25 **************************************************************************/
26
27#ifndef U_THREAD_H_
28#define U_THREAD_H_
29
30#include <errno.h>
31#include <stdint.h>
32#include <stdbool.h>
33#include <string.h>
34
35#include "c11/threads.h"
36#include "detect_os.h"
37#include "macros.h"
38
39#ifdef HAVE_PTHREAD
40#include <signal.h>
41#ifdef HAVE_PTHREAD_NP_H
42#include <pthread_np.h>
43#endif
44#endif
45
46#ifdef __HAIKU__
47#include <OS.h>
48#endif
49
50#if DETECT_OS_LINUX && !defined(ANDROID)
51#include <sched.h>
52#elif defined(_WIN32) && !defined(__CYGWIN__) && _WIN32_WINNT >= 0x0600
53#ifndef WIN32_LEAN_AND_MEAN
54#define WIN32_LEAN_AND_MEAN 1
55#endif
56#include <windows.h>
57#endif
58
59#ifdef __FreeBSD__
60/* pthread_np.h -> sys/param.h -> machine/param.h
61 * - defines ALIGN which clashes with our ALIGN
62 */
63#undef ALIGN
64#define cpu_set_t cpuset_t
65#endif
66
67/* For util_set_thread_affinity to size the mask. */
68#define UTIL_MAX_CPUS               1024  /* this should be enough */
69#define UTIL_MAX_L3_CACHES          UTIL_MAX_CPUS
70
71/* Some highly performance-sensitive thread-local variables like the current GL
72 * context are declared with the initial-exec model on Linux.  glibc allocates a
73 * fixed number of extra slots for initial-exec TLS variables at startup, and
74 * Mesa relies on (even if it's dlopen()ed after init) being able to fit into
75 * those.  This model saves the call to look up the address of the TLS variable.
76 *
77 * However, if we don't have this TLS model available on the platform, then we
78 * still want to use normal TLS (which involves a function call, but not the
79 * expensive pthread_getspecific() or its equivalent).
80 */
81#if DETECT_OS_APPLE
82/* Apple Clang emits wrappers when using thread_local that break module linkage,
83 * but not with __thread
84 */
85#define __THREAD_INITIAL_EXEC __thread
86#elif defined(__GLIBC__)
87#define __THREAD_INITIAL_EXEC thread_local __attribute__((tls_model("initial-exec")))
88#define REALLY_INITIAL_EXEC
89#else
90#define __THREAD_INITIAL_EXEC thread_local
91#endif
92
93static inline int
94util_get_current_cpu(void)
95{
96#if DETECT_OS_LINUX && !defined(ANDROID)
97   return sched_getcpu();
98
99#elif defined(_WIN32) && !defined(__CYGWIN__) && _WIN32_WINNT >= 0x0600
100   return GetCurrentProcessorNumber();
101
102#else
103   return -1;
104#endif
105}
106
107static inline int u_thread_create(thrd_t *thrd, int (*routine)(void *), void *param)
108{
109   int ret = thrd_error;
110#ifdef HAVE_PTHREAD
111   sigset_t saved_set, new_set;
112
113   sigfillset(&new_set);
114   sigdelset(&new_set, SIGSYS);
115
116   /* SIGSEGV is commonly used by Vulkan API tracing layers in order to track
117    * accesses in device memory mapped to user space. Blocking the signal hinders
118    * that tracking mechanism.
119    */
120   sigdelset(&new_set, SIGSEGV);
121   pthread_sigmask(SIG_BLOCK, &new_set, &saved_set);
122   ret = thrd_create(thrd, routine, param);
123   pthread_sigmask(SIG_SETMASK, &saved_set, NULL);
124#else
125   ret = thrd_create(thrd, routine, param);
126#endif
127
128   return ret;
129}
130
131static inline void u_thread_setname( const char *name )
132{
133#if defined(HAVE_PTHREAD)
134#if DETECT_OS_LINUX || DETECT_OS_CYGWIN || DETECT_OS_SOLARIS
135   int ret = pthread_setname_np(pthread_self(), name);
136   if (ret == ERANGE) {
137      char buf[16];
138      const size_t len = MIN2(strlen(name), ARRAY_SIZE(buf) - 1);
139      memcpy(buf, name, len);
140      buf[len] = '\0';
141      pthread_setname_np(pthread_self(), buf);
142   }
143#elif DETECT_OS_FREEBSD || DETECT_OS_OPENBSD
144   pthread_set_name_np(pthread_self(), name);
145#elif DETECT_OS_NETBSD
146   pthread_setname_np(pthread_self(), "%s", (void *)name);
147#elif DETECT_OS_APPLE
148   pthread_setname_np(name);
149#elif DETECT_OS_HAIKU
150   rename_thread(find_thread(NULL), name);
151#else
152#warning Not sure how to call pthread_setname_np
153#endif
154#endif
155   (void)name;
156}
157
158/**
159 * Set thread affinity.
160 *
161 * \param thread         Thread
162 * \param mask           Set this affinity mask
163 * \param old_mask       Previous affinity mask returned if not NULL
164 * \param num_mask_bits  Number of bits in both masks
165 * \return  true on success
166 */
167static inline bool
168util_set_thread_affinity(thrd_t thread,
169                         const uint32_t *mask,
170                         uint32_t *old_mask,
171                         unsigned num_mask_bits)
172{
173#if defined(HAVE_PTHREAD_SETAFFINITY)
174   cpu_set_t cpuset;
175
176   if (old_mask) {
177      if (pthread_getaffinity_np(thread, sizeof(cpuset), &cpuset) != 0)
178         return false;
179
180      memset(old_mask, 0, num_mask_bits / 8);
181      for (unsigned i = 0; i < num_mask_bits && i < CPU_SETSIZE; i++) {
182         if (CPU_ISSET(i, &cpuset))
183            old_mask[i / 32] |= 1u << (i % 32);
184      }
185   }
186
187   CPU_ZERO(&cpuset);
188   for (unsigned i = 0; i < num_mask_bits && i < CPU_SETSIZE; i++) {
189      if (mask[i / 32] & (1u << (i % 32)))
190         CPU_SET(i, &cpuset);
191   }
192   return pthread_setaffinity_np(thread, sizeof(cpuset), &cpuset) == 0;
193
194#elif defined(_WIN32) && !defined(__CYGWIN__)
195   DWORD_PTR m = mask[0];
196
197   if (sizeof(m) > 4 && num_mask_bits > 32)
198      m |= (uint64_t)mask[1] << 32;
199
200   m = SetThreadAffinityMask(thread, m);
201   if (!m)
202      return false;
203
204   if (old_mask) {
205      memset(old_mask, 0, num_mask_bits / 8);
206
207      old_mask[0] = m;
208#ifdef _WIN64
209      old_mask[1] = m >> 32;
210#endif
211   }
212
213   return true;
214#else
215   return false;
216#endif
217}
218
219static inline bool
220util_set_current_thread_affinity(const uint32_t *mask,
221                                 uint32_t *old_mask,
222                                 unsigned num_mask_bits)
223{
224#if defined(HAVE_PTHREAD_SETAFFINITY)
225   return util_set_thread_affinity(pthread_self(), mask, old_mask,
226                                   num_mask_bits);
227
228#elif defined(_WIN32) && !defined(__CYGWIN__)
229   /* The GetCurrentThreadId() handle is only valid within the current thread. */
230   return util_set_thread_affinity(GetCurrentThread(), mask, old_mask,
231                                   num_mask_bits);
232
233#else
234   return false;
235#endif
236}
237
238
239/*
240 * Thread statistics.
241 */
242
243/* Return the time of a thread's CPU time clock. */
244static inline int64_t
245util_thread_get_time_nano(thrd_t thread)
246{
247#if defined(HAVE_PTHREAD) && !defined(__APPLE__) && !defined(__HAIKU__)
248   struct timespec ts;
249   clockid_t cid;
250
251   pthread_getcpuclockid(thread, &cid);
252   clock_gettime(cid, &ts);
253   return (int64_t)ts.tv_sec * 1000000000 + ts.tv_nsec;
254#else
255   (void)thread;
256   return 0;
257#endif
258}
259
260/* Return the time of the current thread's CPU time clock. */
261static inline int64_t
262util_current_thread_get_time_nano(void)
263{
264#if defined(HAVE_PTHREAD)
265   return util_thread_get_time_nano(pthread_self());
266
267#elif defined(_WIN32) && !defined(__CYGWIN__)
268   /* The GetCurrentThreadId() handle is only valid within the current thread. */
269   return util_thread_get_time_nano(GetCurrentThread());
270
271#else
272   return 0;
273#endif
274}
275
276static inline bool u_thread_is_self(thrd_t thread)
277{
278#if defined(HAVE_PTHREAD)
279   return pthread_equal(pthread_self(), thread);
280#endif
281   return false;
282}
283
284/*
285 * util_barrier
286 */
287
288#if defined(HAVE_PTHREAD) && !defined(__APPLE__) && !defined(__HAIKU__)
289
290typedef pthread_barrier_t util_barrier;
291
292static inline void util_barrier_init(util_barrier *barrier, unsigned count)
293{
294   pthread_barrier_init(barrier, NULL, count);
295}
296
297static inline void util_barrier_destroy(util_barrier *barrier)
298{
299   pthread_barrier_destroy(barrier);
300}
301
302static inline bool util_barrier_wait(util_barrier *barrier)
303{
304   return pthread_barrier_wait(barrier) == PTHREAD_BARRIER_SERIAL_THREAD;
305}
306
307
308#else /* If the OS doesn't have its own, implement barriers using a mutex and a condvar */
309
310typedef struct {
311   unsigned count;
312   unsigned waiters;
313   uint64_t sequence;
314   mtx_t mutex;
315   cnd_t condvar;
316} util_barrier;
317
318static inline void util_barrier_init(util_barrier *barrier, unsigned count)
319{
320   barrier->count = count;
321   barrier->waiters = 0;
322   barrier->sequence = 0;
323   (void) mtx_init(&barrier->mutex, mtx_plain);
324   cnd_init(&barrier->condvar);
325}
326
327static inline void util_barrier_destroy(util_barrier *barrier)
328{
329   assert(barrier->waiters == 0);
330   mtx_destroy(&barrier->mutex);
331   cnd_destroy(&barrier->condvar);
332}
333
334static inline bool util_barrier_wait(util_barrier *barrier)
335{
336   mtx_lock(&barrier->mutex);
337
338   assert(barrier->waiters < barrier->count);
339   barrier->waiters++;
340
341   if (barrier->waiters < barrier->count) {
342      uint64_t sequence = barrier->sequence;
343
344      do {
345         cnd_wait(&barrier->condvar, &barrier->mutex);
346      } while (sequence == barrier->sequence);
347   } else {
348      barrier->waiters = 0;
349      barrier->sequence++;
350      cnd_broadcast(&barrier->condvar);
351   }
352
353   mtx_unlock(&barrier->mutex);
354
355   return true;
356}
357
358#endif
359
360/*
361 * Thread-id's.
362 *
363 * thrd_current() is not portable to windows (or at least not in a desirable
364 * way), so thread_id's provide an alternative mechanism
365 */
366
367#ifdef _WIN32
368typedef DWORD thread_id;
369#else
370typedef thrd_t thread_id;
371#endif
372
373static inline thread_id
374util_get_thread_id(void)
375{
376   /*
377    * XXX: Callers of of this function assume it is a lightweight function.
378    * But unfortunately C11's thrd_current() gives no such guarantees.  In
379    * fact, it's pretty hard to have a compliant implementation of
380    * thrd_current() on Windows with such characteristics.  So for now, we
381    * side-step this mess and use Windows thread primitives directly here.
382    */
383#ifdef _WIN32
384   return GetCurrentThreadId();
385#else
386   return thrd_current();
387#endif
388}
389
390
391static inline int
392util_thread_id_equal(thread_id t1, thread_id t2)
393{
394#ifdef _WIN32
395   return t1 == t2;
396#else
397   return thrd_equal(t1, t2);
398#endif
399}
400
401#endif /* U_THREAD_H_ */
402