1 /*
2 * Copyright © 2008 Intel Corporation
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice (including the next
12 * paragraph) shall be included in all copies or substantial portions of the
13 * Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
21 * IN THE SOFTWARE.
22 *
23 * Authors:
24 * Eric Anholt <eric@anholt.net>
25 *
26 */
27
28 /**
29 * \file
30 * \brief Support for GL_ARB_sync and EGL_KHR_fence_sync.
31 *
32 * GL_ARB_sync is implemented by flushing the current batchbuffer and keeping a
33 * reference on it. We can then check for completion or wait for completion
34 * using the normal buffer object mechanisms. This does mean that if an
35 * application is using many sync objects, it will emit small batchbuffers
36 * which may end up being a significant overhead. In other tests of removing
37 * gratuitous batchbuffer syncs in Mesa, it hasn't appeared to be a significant
38 * performance bottleneck, though.
39 */
40
41 #include <libsync.h> /* Requires Android or libdrm-2.4.72 */
42
43 #include "main/imports.h"
44
45 #include "brw_context.h"
46 #include "intel_batchbuffer.h"
47
48 struct brw_fence {
49 struct brw_context *brw;
50
51 enum brw_fence_type {
52 /** The fence waits for completion of brw_fence::batch_bo. */
53 BRW_FENCE_TYPE_BO_WAIT,
54
55 /** The fence waits for brw_fence::sync_fd to signal. */
56 BRW_FENCE_TYPE_SYNC_FD,
57 } type;
58
59 union {
60 struct brw_bo *batch_bo;
61
62 /* This struct owns the fd. */
63 int sync_fd;
64 };
65
66 mtx_t mutex;
67 bool signalled;
68 };
69
70 struct brw_gl_sync {
71 struct gl_sync_object gl;
72 struct brw_fence fence;
73 };
74
75 static void
brw_fence_init(struct brw_context * brw,struct brw_fence * fence,enum brw_fence_type type)76 brw_fence_init(struct brw_context *brw, struct brw_fence *fence,
77 enum brw_fence_type type)
78 {
79 fence->brw = brw;
80 fence->type = type;
81 mtx_init(&fence->mutex, mtx_plain);
82
83 switch (type) {
84 case BRW_FENCE_TYPE_BO_WAIT:
85 fence->batch_bo = NULL;
86 break;
87 case BRW_FENCE_TYPE_SYNC_FD:
88 fence->sync_fd = -1;
89 break;
90 }
91 }
92
93 static void
brw_fence_finish(struct brw_fence * fence)94 brw_fence_finish(struct brw_fence *fence)
95 {
96 switch (fence->type) {
97 case BRW_FENCE_TYPE_BO_WAIT:
98 if (fence->batch_bo)
99 brw_bo_unreference(fence->batch_bo);
100 break;
101 case BRW_FENCE_TYPE_SYNC_FD:
102 if (fence->sync_fd != -1)
103 close(fence->sync_fd);
104 break;
105 }
106
107 mtx_destroy(&fence->mutex);
108 }
109
110 static bool MUST_CHECK
brw_fence_insert_locked(struct brw_context * brw,struct brw_fence * fence)111 brw_fence_insert_locked(struct brw_context *brw, struct brw_fence *fence)
112 {
113 __DRIcontext *driContext = brw->driContext;
114 __DRIdrawable *driDrawable = driContext->driDrawablePriv;
115
116 /*
117 * From KHR_fence_sync:
118 *
119 * When the condition of the sync object is satisfied by the fence
120 * command, the sync is signaled by the associated client API context,
121 * causing any eglClientWaitSyncKHR commands (see below) blocking on
122 * <sync> to unblock. The only condition currently supported is
123 * EGL_SYNC_PRIOR_COMMANDS_COMPLETE_KHR, which is satisfied by
124 * completion of the fence command corresponding to the sync object,
125 * and all preceding commands in the associated client API context's
126 * command stream. The sync object will not be signaled until all
127 * effects from these commands on the client API's internal and
128 * framebuffer state are fully realized. No other state is affected by
129 * execution of the fence command.
130 *
131 * Note the emphasis there on ensuring that the framebuffer is fully
132 * realised before the fence is signaled. We cannot just flush the batch,
133 * but must also resolve the drawable first. The importance of this is,
134 * for example, in creating a fence for a frame to be passed to a
135 * remote compositor. Without us flushing the drawable explicitly, the
136 * resolve will be in a following batch (when the client finally calls
137 * SwapBuffers, or triggers a resolve via some other path) and so the
138 * compositor may read the incomplete framebuffer instead.
139 */
140 if (driDrawable)
141 intel_resolve_for_dri2_flush(brw, driDrawable);
142 brw_emit_mi_flush(brw);
143
144 switch (fence->type) {
145 case BRW_FENCE_TYPE_BO_WAIT:
146 assert(!fence->batch_bo);
147 assert(!fence->signalled);
148
149 fence->batch_bo = brw->batch.batch.bo;
150 brw_bo_reference(fence->batch_bo);
151
152 if (intel_batchbuffer_flush(brw) < 0) {
153 brw_bo_unreference(fence->batch_bo);
154 fence->batch_bo = NULL;
155 return false;
156 }
157 break;
158 case BRW_FENCE_TYPE_SYNC_FD:
159 assert(!fence->signalled);
160
161 if (fence->sync_fd == -1) {
162 /* Create an out-fence that signals after all pending commands
163 * complete.
164 */
165 if (intel_batchbuffer_flush_fence(brw, -1, &fence->sync_fd) < 0)
166 return false;
167 assert(fence->sync_fd != -1);
168 } else {
169 /* Wait on the in-fence before executing any subsequently submitted
170 * commands.
171 */
172 if (intel_batchbuffer_flush(brw) < 0)
173 return false;
174
175 /* Emit a dummy batch just for the fence. */
176 brw_emit_mi_flush(brw);
177 if (intel_batchbuffer_flush_fence(brw, fence->sync_fd, NULL) < 0)
178 return false;
179 }
180 break;
181 }
182
183 return true;
184 }
185
186 static bool MUST_CHECK
brw_fence_insert(struct brw_context * brw,struct brw_fence * fence)187 brw_fence_insert(struct brw_context *brw, struct brw_fence *fence)
188 {
189 bool ret;
190
191 mtx_lock(&fence->mutex);
192 ret = brw_fence_insert_locked(brw, fence);
193 mtx_unlock(&fence->mutex);
194
195 return ret;
196 }
197
198 static bool
brw_fence_has_completed_locked(struct brw_fence * fence)199 brw_fence_has_completed_locked(struct brw_fence *fence)
200 {
201 if (fence->signalled)
202 return true;
203
204 switch (fence->type) {
205 case BRW_FENCE_TYPE_BO_WAIT:
206 if (!fence->batch_bo) {
207 /* There may be no batch if intel_batchbuffer_flush() failed. */
208 return false;
209 }
210
211 if (brw_bo_busy(fence->batch_bo))
212 return false;
213
214 brw_bo_unreference(fence->batch_bo);
215 fence->batch_bo = NULL;
216 fence->signalled = true;
217
218 return true;
219
220 case BRW_FENCE_TYPE_SYNC_FD:
221 assert(fence->sync_fd != -1);
222
223 if (sync_wait(fence->sync_fd, 0) == -1)
224 return false;
225
226 fence->signalled = true;
227
228 return true;
229 }
230
231 return false;
232 }
233
234 static bool
brw_fence_has_completed(struct brw_fence * fence)235 brw_fence_has_completed(struct brw_fence *fence)
236 {
237 bool ret;
238
239 mtx_lock(&fence->mutex);
240 ret = brw_fence_has_completed_locked(fence);
241 mtx_unlock(&fence->mutex);
242
243 return ret;
244 }
245
246 static bool
brw_fence_client_wait_locked(struct brw_context * brw,struct brw_fence * fence,uint64_t timeout)247 brw_fence_client_wait_locked(struct brw_context *brw, struct brw_fence *fence,
248 uint64_t timeout)
249 {
250 int32_t timeout_i32;
251
252 if (fence->signalled)
253 return true;
254
255 switch (fence->type) {
256 case BRW_FENCE_TYPE_BO_WAIT:
257 if (!fence->batch_bo) {
258 /* There may be no batch if intel_batchbuffer_flush() failed. */
259 return false;
260 }
261
262 /* DRM_IOCTL_I915_GEM_WAIT uses a signed 64 bit timeout and returns
263 * immediately for timeouts <= 0. The best we can do is to clamp the
264 * timeout to INT64_MAX. This limits the maximum timeout from 584 years to
265 * 292 years - likely not a big deal.
266 */
267 if (timeout > INT64_MAX)
268 timeout = INT64_MAX;
269
270 if (brw_bo_wait(fence->batch_bo, timeout) != 0)
271 return false;
272
273 fence->signalled = true;
274 brw_bo_unreference(fence->batch_bo);
275 fence->batch_bo = NULL;
276
277 return true;
278 case BRW_FENCE_TYPE_SYNC_FD:
279 if (fence->sync_fd == -1)
280 return false;
281
282 if (timeout > INT32_MAX)
283 timeout_i32 = -1;
284 else
285 timeout_i32 = timeout;
286
287 if (sync_wait(fence->sync_fd, timeout_i32) == -1)
288 return false;
289
290 fence->signalled = true;
291 return true;
292 }
293
294 assert(!"bad enum brw_fence_type");
295 return false;
296 }
297
298 /**
299 * Return true if the function successfully signals or has already signalled.
300 * (This matches the behavior expected from __DRI2fence::client_wait_sync).
301 */
302 static bool
brw_fence_client_wait(struct brw_context * brw,struct brw_fence * fence,uint64_t timeout)303 brw_fence_client_wait(struct brw_context *brw, struct brw_fence *fence,
304 uint64_t timeout)
305 {
306 bool ret;
307
308 mtx_lock(&fence->mutex);
309 ret = brw_fence_client_wait_locked(brw, fence, timeout);
310 mtx_unlock(&fence->mutex);
311
312 return ret;
313 }
314
315 static void
brw_fence_server_wait(struct brw_context * brw,struct brw_fence * fence)316 brw_fence_server_wait(struct brw_context *brw, struct brw_fence *fence)
317 {
318 switch (fence->type) {
319 case BRW_FENCE_TYPE_BO_WAIT:
320 /* We have nothing to do for WaitSync. Our GL command stream is sequential,
321 * so given that the sync object has already flushed the batchbuffer, any
322 * batchbuffers coming after this waitsync will naturally not occur until
323 * the previous one is done.
324 */
325 break;
326 case BRW_FENCE_TYPE_SYNC_FD:
327 assert(fence->sync_fd != -1);
328
329 /* The user wants explicit synchronization, so give them what they want. */
330 if (!brw_fence_insert(brw, fence)) {
331 /* FIXME: There exists no way yet to report an error here. If an error
332 * occurs, continue silently and hope for the best.
333 */
334 }
335 break;
336 }
337 }
338
339 static struct gl_sync_object *
brw_gl_new_sync(struct gl_context * ctx)340 brw_gl_new_sync(struct gl_context *ctx)
341 {
342 struct brw_gl_sync *sync;
343
344 sync = calloc(1, sizeof(*sync));
345 if (!sync)
346 return NULL;
347
348 return &sync->gl;
349 }
350
351 static void
brw_gl_delete_sync(struct gl_context * ctx,struct gl_sync_object * _sync)352 brw_gl_delete_sync(struct gl_context *ctx, struct gl_sync_object *_sync)
353 {
354 struct brw_gl_sync *sync = (struct brw_gl_sync *) _sync;
355
356 brw_fence_finish(&sync->fence);
357 free(sync);
358 }
359
360 static void
brw_gl_fence_sync(struct gl_context * ctx,struct gl_sync_object * _sync,GLenum condition,GLbitfield flags)361 brw_gl_fence_sync(struct gl_context *ctx, struct gl_sync_object *_sync,
362 GLenum condition, GLbitfield flags)
363 {
364 struct brw_context *brw = brw_context(ctx);
365 struct brw_gl_sync *sync = (struct brw_gl_sync *) _sync;
366
367 /* brw_fence_insert_locked() assumes it must do a complete flush */
368 assert(condition == GL_SYNC_GPU_COMMANDS_COMPLETE);
369
370 brw_fence_init(brw, &sync->fence, BRW_FENCE_TYPE_BO_WAIT);
371
372 if (!brw_fence_insert_locked(brw, &sync->fence)) {
373 /* FIXME: There exists no way to report a GL error here. If an error
374 * occurs, continue silently and hope for the best.
375 */
376 }
377 }
378
379 static void
brw_gl_client_wait_sync(struct gl_context * ctx,struct gl_sync_object * _sync,GLbitfield flags,GLuint64 timeout)380 brw_gl_client_wait_sync(struct gl_context *ctx, struct gl_sync_object *_sync,
381 GLbitfield flags, GLuint64 timeout)
382 {
383 struct brw_context *brw = brw_context(ctx);
384 struct brw_gl_sync *sync = (struct brw_gl_sync *) _sync;
385
386 if (brw_fence_client_wait(brw, &sync->fence, timeout))
387 sync->gl.StatusFlag = 1;
388 }
389
390 static void
brw_gl_server_wait_sync(struct gl_context * ctx,struct gl_sync_object * _sync,GLbitfield flags,GLuint64 timeout)391 brw_gl_server_wait_sync(struct gl_context *ctx, struct gl_sync_object *_sync,
392 GLbitfield flags, GLuint64 timeout)
393 {
394 struct brw_context *brw = brw_context(ctx);
395 struct brw_gl_sync *sync = (struct brw_gl_sync *) _sync;
396
397 brw_fence_server_wait(brw, &sync->fence);
398 }
399
400 static void
brw_gl_check_sync(struct gl_context * ctx,struct gl_sync_object * _sync)401 brw_gl_check_sync(struct gl_context *ctx, struct gl_sync_object *_sync)
402 {
403 struct brw_gl_sync *sync = (struct brw_gl_sync *) _sync;
404
405 if (brw_fence_has_completed(&sync->fence))
406 sync->gl.StatusFlag = 1;
407 }
408
409 void
brw_init_syncobj_functions(struct dd_function_table * functions)410 brw_init_syncobj_functions(struct dd_function_table *functions)
411 {
412 functions->NewSyncObject = brw_gl_new_sync;
413 functions->DeleteSyncObject = brw_gl_delete_sync;
414 functions->FenceSync = brw_gl_fence_sync;
415 functions->CheckSync = brw_gl_check_sync;
416 functions->ClientWaitSync = brw_gl_client_wait_sync;
417 functions->ServerWaitSync = brw_gl_server_wait_sync;
418 }
419
420 static void *
brw_dri_create_fence(__DRIcontext * ctx)421 brw_dri_create_fence(__DRIcontext *ctx)
422 {
423 struct brw_context *brw = ctx->driverPrivate;
424 struct brw_fence *fence;
425
426 fence = calloc(1, sizeof(*fence));
427 if (!fence)
428 return NULL;
429
430 brw_fence_init(brw, fence, BRW_FENCE_TYPE_BO_WAIT);
431
432 if (!brw_fence_insert_locked(brw, fence)) {
433 brw_fence_finish(fence);
434 free(fence);
435 return NULL;
436 }
437
438 return fence;
439 }
440
441 static void
brw_dri_destroy_fence(__DRIscreen * dri_screen,void * _fence)442 brw_dri_destroy_fence(__DRIscreen *dri_screen, void *_fence)
443 {
444 struct brw_fence *fence = _fence;
445
446 brw_fence_finish(fence);
447 free(fence);
448 }
449
450 static GLboolean
brw_dri_client_wait_sync(__DRIcontext * ctx,void * _fence,unsigned flags,uint64_t timeout)451 brw_dri_client_wait_sync(__DRIcontext *ctx, void *_fence, unsigned flags,
452 uint64_t timeout)
453 {
454 struct brw_fence *fence = _fence;
455
456 return brw_fence_client_wait(fence->brw, fence, timeout);
457 }
458
459 static void
brw_dri_server_wait_sync(__DRIcontext * ctx,void * _fence,unsigned flags)460 brw_dri_server_wait_sync(__DRIcontext *ctx, void *_fence, unsigned flags)
461 {
462 struct brw_fence *fence = _fence;
463
464 /* We might be called here with a NULL fence as a result of WaitSyncKHR
465 * on a EGL_KHR_reusable_sync fence. Nothing to do here in such case.
466 */
467 if (!fence)
468 return;
469
470 brw_fence_server_wait(fence->brw, fence);
471 }
472
473 static unsigned
brw_dri_get_capabilities(__DRIscreen * dri_screen)474 brw_dri_get_capabilities(__DRIscreen *dri_screen)
475 {
476 struct intel_screen *screen = dri_screen->driverPrivate;
477 unsigned caps = 0;
478
479 if (screen->has_exec_fence)
480 caps |= __DRI_FENCE_CAP_NATIVE_FD;
481
482 return caps;
483 }
484
485 static void *
brw_dri_create_fence_fd(__DRIcontext * dri_ctx,int fd)486 brw_dri_create_fence_fd(__DRIcontext *dri_ctx, int fd)
487 {
488 struct brw_context *brw = dri_ctx->driverPrivate;
489 struct brw_fence *fence;
490
491 assert(brw->screen->has_exec_fence);
492
493 fence = calloc(1, sizeof(*fence));
494 if (!fence)
495 return NULL;
496
497 brw_fence_init(brw, fence, BRW_FENCE_TYPE_SYNC_FD);
498
499 if (fd == -1) {
500 /* Create an out-fence fd */
501 if (!brw_fence_insert_locked(brw, fence))
502 goto fail;
503 } else {
504 /* Import the sync fd as an in-fence. */
505 fence->sync_fd = dup(fd);
506 }
507
508 assert(fence->sync_fd != -1);
509
510 return fence;
511
512 fail:
513 brw_fence_finish(fence);
514 free(fence);
515 return NULL;
516 }
517
518 static int
brw_dri_get_fence_fd_locked(struct brw_fence * fence)519 brw_dri_get_fence_fd_locked(struct brw_fence *fence)
520 {
521 assert(fence->type == BRW_FENCE_TYPE_SYNC_FD);
522 return dup(fence->sync_fd);
523 }
524
525 static int
brw_dri_get_fence_fd(__DRIscreen * dri_screen,void * _fence)526 brw_dri_get_fence_fd(__DRIscreen *dri_screen, void *_fence)
527 {
528 struct brw_fence *fence = _fence;
529 int fd;
530
531 mtx_lock(&fence->mutex);
532 fd = brw_dri_get_fence_fd_locked(fence);
533 mtx_unlock(&fence->mutex);
534
535 return fd;
536 }
537
538 const __DRI2fenceExtension intelFenceExtension = {
539 .base = { __DRI2_FENCE, 2 },
540
541 .create_fence = brw_dri_create_fence,
542 .destroy_fence = brw_dri_destroy_fence,
543 .client_wait_sync = brw_dri_client_wait_sync,
544 .server_wait_sync = brw_dri_server_wait_sync,
545 .get_fence_from_cl_event = NULL,
546 .get_capabilities = brw_dri_get_capabilities,
547 .create_fence_fd = brw_dri_create_fence_fd,
548 .get_fence_fd = brw_dri_get_fence_fd,
549 };
550