1 /*
2 * Copyright © 2018 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 shall be included
12 * in all copies or substantial portions of the Software.
13 *
14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
15 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
17 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
18 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
19 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
20 * DEALINGS IN THE SOFTWARE.
21 */
22
23 /**
24 * @file crocus_fence.c
25 *
26 * Fences for driver and IPC serialisation, scheduling and synchronisation.
27 */
28
29 #include "util/u_inlines.h"
30 #include "intel/common/intel_gem.h"
31
32 #include "crocus_batch.h"
33 #include "crocus_bufmgr.h"
34 #include "crocus_context.h"
35 #include "crocus_fence.h"
36 #include "crocus_screen.h"
37
38 static uint32_t
gem_syncobj_create(int fd,uint32_t flags)39 gem_syncobj_create(int fd, uint32_t flags)
40 {
41 struct drm_syncobj_create args = {
42 .flags = flags,
43 };
44
45 intel_ioctl(fd, DRM_IOCTL_SYNCOBJ_CREATE, &args);
46
47 return args.handle;
48 }
49
50 static void
gem_syncobj_destroy(int fd,uint32_t handle)51 gem_syncobj_destroy(int fd, uint32_t handle)
52 {
53 struct drm_syncobj_destroy args = {
54 .handle = handle,
55 };
56
57 intel_ioctl(fd, DRM_IOCTL_SYNCOBJ_DESTROY, &args);
58 }
59
60 /**
61 * Make a new sync-point.
62 */
63 struct crocus_syncobj *
crocus_create_syncobj(struct crocus_screen * screen)64 crocus_create_syncobj(struct crocus_screen *screen)
65 {
66 struct crocus_syncobj *syncobj = malloc(sizeof(*syncobj));
67
68 if (!syncobj)
69 return NULL;
70
71 syncobj->handle = gem_syncobj_create(screen->fd, 0);
72 assert(syncobj->handle);
73
74 pipe_reference_init(&syncobj->ref, 1);
75
76 return syncobj;
77 }
78
79 void
crocus_syncobj_destroy(struct crocus_screen * screen,struct crocus_syncobj * syncobj)80 crocus_syncobj_destroy(struct crocus_screen *screen,
81 struct crocus_syncobj *syncobj)
82 {
83 gem_syncobj_destroy(screen->fd, syncobj->handle);
84 free(syncobj);
85 }
86
87 /**
88 * Add a sync-point to the batch, with the given flags.
89 *
90 * \p flags One of I915_EXEC_FENCE_WAIT or I915_EXEC_FENCE_SIGNAL.
91 */
92 void
crocus_batch_add_syncobj(struct crocus_batch * batch,struct crocus_syncobj * syncobj,unsigned flags)93 crocus_batch_add_syncobj(struct crocus_batch *batch,
94 struct crocus_syncobj *syncobj, unsigned flags)
95 {
96 struct drm_i915_gem_exec_fence *fence =
97 util_dynarray_grow(&batch->exec_fences, struct drm_i915_gem_exec_fence, 1);
98
99 *fence = (struct drm_i915_gem_exec_fence){
100 .handle = syncobj->handle,
101 .flags = flags,
102 };
103
104 struct crocus_syncobj **store =
105 util_dynarray_grow(&batch->syncobjs, struct crocus_syncobj *, 1);
106
107 *store = NULL;
108 crocus_syncobj_reference(batch->screen, store, syncobj);
109 }
110
111 /**
112 * Walk through a batch's dependencies (any I915_EXEC_FENCE_WAIT syncobjs)
113 * and unreference any which have already passed.
114 *
115 * Sometimes the compute batch is seldom used, and accumulates references
116 * to stale render batches that are no longer of interest, so we can free
117 * those up.
118 */
119 static void
clear_stale_syncobjs(struct crocus_batch * batch)120 clear_stale_syncobjs(struct crocus_batch *batch)
121 {
122 struct crocus_screen *screen = batch->screen;
123
124 int n = util_dynarray_num_elements(&batch->syncobjs, struct crocus_syncobj *);
125
126 assert(n == util_dynarray_num_elements(&batch->exec_fences,
127 struct drm_i915_gem_exec_fence));
128
129 /* Skip the first syncobj, as it's the signalling one. */
130 for (int i = n - 1; i > 1; i--) {
131 struct crocus_syncobj **syncobj =
132 util_dynarray_element(&batch->syncobjs, struct crocus_syncobj *, i);
133 struct drm_i915_gem_exec_fence *fence =
134 util_dynarray_element(&batch->exec_fences,
135 struct drm_i915_gem_exec_fence, i);
136 assert(fence->flags & I915_EXEC_FENCE_WAIT);
137
138 if (crocus_wait_syncobj(&screen->base, *syncobj, 0))
139 continue;
140
141 /* This sync object has already passed, there's no need to continue
142 * marking it as a dependency; we can stop holding on to the reference.
143 */
144 crocus_syncobj_reference(screen, syncobj, NULL);
145
146 /* Remove it from the lists; move the last element here. */
147 struct crocus_syncobj **nth_syncobj =
148 util_dynarray_pop_ptr(&batch->syncobjs, struct crocus_syncobj *);
149 struct drm_i915_gem_exec_fence *nth_fence =
150 util_dynarray_pop_ptr(&batch->exec_fences,
151 struct drm_i915_gem_exec_fence);
152
153 if (syncobj != nth_syncobj) {
154 *syncobj = *nth_syncobj;
155 memcpy(fence, nth_fence, sizeof(*fence));
156 }
157 }
158 }
159
160 /* ------------------------------------------------------------------- */
161
162 struct pipe_fence_handle {
163 struct pipe_reference ref;
164
165 struct pipe_context *unflushed_ctx;
166
167 struct crocus_fine_fence *fine[CROCUS_BATCH_COUNT];
168 };
169
170 static void
crocus_fence_destroy(struct pipe_screen * p_screen,struct pipe_fence_handle * fence)171 crocus_fence_destroy(struct pipe_screen *p_screen,
172 struct pipe_fence_handle *fence)
173 {
174 struct crocus_screen *screen = (struct crocus_screen *)p_screen;
175
176 for (unsigned i = 0; i < ARRAY_SIZE(fence->fine); i++)
177 crocus_fine_fence_reference(screen, &fence->fine[i], NULL);
178
179 free(fence);
180 }
181
182 static void
crocus_fence_reference(struct pipe_screen * p_screen,struct pipe_fence_handle ** dst,struct pipe_fence_handle * src)183 crocus_fence_reference(struct pipe_screen *p_screen,
184 struct pipe_fence_handle **dst,
185 struct pipe_fence_handle *src)
186 {
187 if (pipe_reference(&(*dst)->ref, &src->ref))
188 crocus_fence_destroy(p_screen, *dst);
189
190 *dst = src;
191 }
192
193 bool
crocus_wait_syncobj(struct pipe_screen * p_screen,struct crocus_syncobj * syncobj,int64_t timeout_nsec)194 crocus_wait_syncobj(struct pipe_screen *p_screen,
195 struct crocus_syncobj *syncobj, int64_t timeout_nsec)
196 {
197 if (!syncobj)
198 return false;
199
200 struct crocus_screen *screen = (struct crocus_screen *)p_screen;
201 struct drm_syncobj_wait args = {
202 .handles = (uintptr_t)&syncobj->handle,
203 .count_handles = 1,
204 .timeout_nsec = timeout_nsec,
205 };
206 return intel_ioctl(screen->fd, DRM_IOCTL_SYNCOBJ_WAIT, &args);
207 }
208
209 static void
crocus_fence_flush(struct pipe_context * ctx,struct pipe_fence_handle ** out_fence,unsigned flags)210 crocus_fence_flush(struct pipe_context *ctx,
211 struct pipe_fence_handle **out_fence, unsigned flags)
212 {
213 struct crocus_screen *screen = (void *)ctx->screen;
214 struct crocus_context *ice = (struct crocus_context *)ctx;
215
216 const bool deferred = flags & PIPE_FLUSH_DEFERRED;
217
218 if (!deferred) {
219 for (unsigned i = 0; i < ice->batch_count; i++)
220 crocus_batch_flush(&ice->batches[i]);
221 }
222
223 if (!out_fence)
224 return;
225
226 struct pipe_fence_handle *fence = calloc(1, sizeof(*fence));
227 if (!fence)
228 return;
229
230 pipe_reference_init(&fence->ref, 1);
231
232 if (deferred)
233 fence->unflushed_ctx = ctx;
234
235 for (unsigned b = 0; b < ice->batch_count; b++) {
236 struct crocus_batch *batch = &ice->batches[b];
237
238 if (deferred && crocus_batch_bytes_used(batch) > 0) {
239 struct crocus_fine_fence *fine =
240 crocus_fine_fence_new(batch, CROCUS_FENCE_BOTTOM_OF_PIPE);
241 crocus_fine_fence_reference(screen, &fence->fine[b], fine);
242 crocus_fine_fence_reference(screen, &fine, NULL);
243 } else {
244 /* This batch has no commands queued up (perhaps we just flushed,
245 * or all the commands are on the other batch). Wait for the last
246 * syncobj on this engine - unless it's already finished by now.
247 */
248 if (crocus_fine_fence_signaled(batch->last_fence))
249 continue;
250
251 crocus_fine_fence_reference(screen, &fence->fine[b],
252 batch->last_fence);
253 }
254 }
255
256 crocus_fence_reference(ctx->screen, out_fence, NULL);
257 *out_fence = fence;
258 }
259
260 static void
crocus_fence_await(struct pipe_context * ctx,struct pipe_fence_handle * fence)261 crocus_fence_await(struct pipe_context *ctx, struct pipe_fence_handle *fence)
262 {
263 struct crocus_context *ice = (struct crocus_context *)ctx;
264
265 /* Unflushed fences from the same context are no-ops. */
266 if (ctx && ctx == fence->unflushed_ctx)
267 return;
268
269 for (unsigned i = 0; i < ARRAY_SIZE(fence->fine); i++) {
270 struct crocus_fine_fence *fine = fence->fine[i];
271
272 if (crocus_fine_fence_signaled(fine))
273 continue;
274
275 for (unsigned b = 0; b < ice->batch_count; b++) {
276 struct crocus_batch *batch = &ice->batches[b];
277
278 /* We're going to make any future work in this batch wait for our
279 * fence to have gone by. But any currently queued work doesn't
280 * need to wait. Flush the batch now, so it can happen sooner.
281 */
282 crocus_batch_flush(batch);
283
284 /* Before adding a new reference, clean out any stale ones. */
285 clear_stale_syncobjs(batch);
286
287 crocus_batch_add_syncobj(batch, fine->syncobj, I915_EXEC_FENCE_WAIT);
288 }
289 }
290 }
291
292 #define NSEC_PER_SEC (1000 * USEC_PER_SEC)
293 #define USEC_PER_SEC (1000 * MSEC_PER_SEC)
294 #define MSEC_PER_SEC (1000)
295
296 static uint64_t
gettime_ns(void)297 gettime_ns(void)
298 {
299 struct timespec current;
300 clock_gettime(CLOCK_MONOTONIC, ¤t);
301 return (uint64_t)current.tv_sec * NSEC_PER_SEC + current.tv_nsec;
302 }
303
304 static uint64_t
rel2abs(uint64_t timeout)305 rel2abs(uint64_t timeout)
306 {
307 if (timeout == 0)
308 return 0;
309
310 uint64_t current_time = gettime_ns();
311 uint64_t max_timeout = (uint64_t)INT64_MAX - current_time;
312
313 timeout = MIN2(max_timeout, timeout);
314
315 return current_time + timeout;
316 }
317
318 static bool
crocus_fence_finish(struct pipe_screen * p_screen,struct pipe_context * ctx,struct pipe_fence_handle * fence,uint64_t timeout)319 crocus_fence_finish(struct pipe_screen *p_screen, struct pipe_context *ctx,
320 struct pipe_fence_handle *fence, uint64_t timeout)
321 {
322 ctx = threaded_context_unwrap_sync(ctx);
323 struct crocus_context *ice = (struct crocus_context *)ctx;
324 struct crocus_screen *screen = (struct crocus_screen *)p_screen;
325
326 /* If we created the fence with PIPE_FLUSH_DEFERRED, we may not have
327 * flushed yet. Check if our syncobj is the current batch's signalling
328 * syncobj - if so, we haven't flushed and need to now.
329 *
330 * The Gallium docs mention that a flush will occur if \p ctx matches
331 * the context the fence was created with. It may be NULL, so we check
332 * that it matches first.
333 */
334 if (ctx && ctx == fence->unflushed_ctx) {
335 for (unsigned i = 0; i < ice->batch_count; i++) {
336 struct crocus_fine_fence *fine = fence->fine[i];
337
338 if (crocus_fine_fence_signaled(fine))
339 continue;
340
341 if (fine->syncobj == crocus_batch_get_signal_syncobj(&ice->batches[i]))
342 crocus_batch_flush(&ice->batches[i]);
343 }
344
345 /* The fence is no longer deferred. */
346 fence->unflushed_ctx = NULL;
347 }
348
349 unsigned int handle_count = 0;
350 uint32_t handles[ARRAY_SIZE(fence->fine)];
351 for (unsigned i = 0; i < ARRAY_SIZE(fence->fine); i++) {
352 struct crocus_fine_fence *fine = fence->fine[i];
353
354 if (crocus_fine_fence_signaled(fine))
355 continue;
356
357 handles[handle_count++] = fine->syncobj->handle;
358 }
359
360 if (handle_count == 0)
361 return true;
362
363 struct drm_syncobj_wait args = {
364 .handles = (uintptr_t)handles,
365 .count_handles = handle_count,
366 .timeout_nsec = rel2abs(timeout),
367 .flags = DRM_SYNCOBJ_WAIT_FLAGS_WAIT_ALL
368 };
369 if (fence->unflushed_ctx) {
370 /* This fence had a deferred flush from another context. We can't
371 * safely flush it here, because the context might be bound to a
372 * different thread, and poking at its internals wouldn't be safe.
373 *
374 * Instead, use the WAIT_FOR_SUBMIT flag to block and hope that
375 * another thread submits the work.
376 */
377 args.flags |= DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT;
378 }
379 return intel_ioctl(screen->fd, DRM_IOCTL_SYNCOBJ_WAIT, &args) == 0;
380 }
381
382 #ifndef SYNC_IOC_MAGIC
383 /* duplicated from linux/sync_file.h to avoid build-time dependency
384 * on new (v4.7) kernel headers. Once distro's are mostly using
385 * something newer than v4.7 drop this and #include <linux/sync_file.h>
386 * instead.
387 */
388 struct sync_merge_data {
389 char name[32];
390 __s32 fd2;
391 __s32 fence;
392 __u32 flags;
393 __u32 pad;
394 };
395
396 #define SYNC_IOC_MAGIC '>'
397 #define SYNC_IOC_MERGE _IOWR(SYNC_IOC_MAGIC, 3, struct sync_merge_data)
398 #endif
399
400 static int
sync_merge_fd(int sync_fd,int new_fd)401 sync_merge_fd(int sync_fd, int new_fd)
402 {
403 if (sync_fd == -1)
404 return new_fd;
405
406 if (new_fd == -1)
407 return sync_fd;
408
409 struct sync_merge_data args = {
410 .name = "crocus fence",
411 .fd2 = new_fd,
412 .fence = -1,
413 };
414
415 intel_ioctl(sync_fd, SYNC_IOC_MERGE, &args);
416 close(new_fd);
417 close(sync_fd);
418
419 return args.fence;
420 }
421
422 static int
crocus_fence_get_fd(struct pipe_screen * p_screen,struct pipe_fence_handle * fence)423 crocus_fence_get_fd(struct pipe_screen *p_screen,
424 struct pipe_fence_handle *fence)
425 {
426 struct crocus_screen *screen = (struct crocus_screen *)p_screen;
427 int fd = -1;
428
429 /* Deferred fences aren't supported. */
430 if (fence->unflushed_ctx)
431 return -1;
432
433 for (unsigned i = 0; i < ARRAY_SIZE(fence->fine); i++) {
434 struct crocus_fine_fence *fine = fence->fine[i];
435
436 if (crocus_fine_fence_signaled(fine))
437 continue;
438
439 struct drm_syncobj_handle args = {
440 .handle = fine->syncobj->handle,
441 .flags = DRM_SYNCOBJ_HANDLE_TO_FD_FLAGS_EXPORT_SYNC_FILE,
442 .fd = -1,
443 };
444
445 intel_ioctl(screen->fd, DRM_IOCTL_SYNCOBJ_HANDLE_TO_FD, &args);
446 fd = sync_merge_fd(fd, args.fd);
447 }
448
449 if (fd == -1) {
450 /* Our fence has no syncobj's recorded. This means that all of the
451 * batches had already completed, their syncobj's had been signalled,
452 * and so we didn't bother to record them. But we're being asked to
453 * export such a fence. So export a dummy already-signalled syncobj.
454 */
455 struct drm_syncobj_handle args = {
456 .flags = DRM_SYNCOBJ_HANDLE_TO_FD_FLAGS_EXPORT_SYNC_FILE,
457 .fd = -1,
458 };
459
460 args.handle = gem_syncobj_create(screen->fd, DRM_SYNCOBJ_CREATE_SIGNALED);
461 intel_ioctl(screen->fd, DRM_IOCTL_SYNCOBJ_HANDLE_TO_FD, &args);
462 gem_syncobj_destroy(screen->fd, args.handle);
463 return args.fd;
464 }
465
466 return fd;
467 }
468
469 static void
crocus_fence_create_fd(struct pipe_context * ctx,struct pipe_fence_handle ** out,int fd,enum pipe_fd_type type)470 crocus_fence_create_fd(struct pipe_context *ctx, struct pipe_fence_handle **out,
471 int fd, enum pipe_fd_type type)
472 {
473 assert(type == PIPE_FD_TYPE_NATIVE_SYNC || type == PIPE_FD_TYPE_SYNCOBJ);
474
475 struct crocus_screen *screen = (struct crocus_screen *)ctx->screen;
476 struct drm_syncobj_handle args = {
477 .fd = fd,
478 };
479
480 if (type == PIPE_FD_TYPE_NATIVE_SYNC) {
481 args.flags = DRM_SYNCOBJ_FD_TO_HANDLE_FLAGS_IMPORT_SYNC_FILE;
482 args.handle = gem_syncobj_create(screen->fd, DRM_SYNCOBJ_CREATE_SIGNALED);
483 }
484
485 if (intel_ioctl(screen->fd, DRM_IOCTL_SYNCOBJ_FD_TO_HANDLE, &args) == -1) {
486 fprintf(stderr, "DRM_IOCTL_SYNCOBJ_FD_TO_HANDLE failed: %s\n",
487 strerror(errno));
488 if (type == PIPE_FD_TYPE_NATIVE_SYNC)
489 gem_syncobj_destroy(screen->fd, args.handle);
490 *out = NULL;
491 return;
492 }
493
494 struct crocus_syncobj *syncobj = malloc(sizeof(*syncobj));
495 if (!syncobj) {
496 *out = NULL;
497 return;
498 }
499 syncobj->handle = args.handle;
500 pipe_reference_init(&syncobj->ref, 1);
501
502 struct crocus_fine_fence *fine = calloc(1, sizeof(*fine));
503 if (!fine) {
504 free(syncobj);
505 *out = NULL;
506 return;
507 }
508
509 static const uint32_t zero = 0;
510
511 /* Fences work in terms of crocus_fine_fence, but we don't actually have a
512 * seqno for an imported fence. So, create a fake one which always
513 * returns as 'not signaled' so we fall back to using the sync object.
514 */
515 fine->seqno = UINT32_MAX;
516 fine->map = &zero;
517 fine->syncobj = syncobj;
518 fine->flags = CROCUS_FENCE_END;
519 pipe_reference_init(&fine->reference, 1);
520
521 struct pipe_fence_handle *fence = calloc(1, sizeof(*fence));
522 if (!fence) {
523 free(fine);
524 free(syncobj);
525 *out = NULL;
526 return;
527 }
528 pipe_reference_init(&fence->ref, 1);
529 fence->fine[0] = fine;
530
531 *out = fence;
532 }
533
534 static void
crocus_fence_signal(struct pipe_context * ctx,struct pipe_fence_handle * fence)535 crocus_fence_signal(struct pipe_context *ctx, struct pipe_fence_handle *fence)
536 {
537 struct crocus_context *ice = (struct crocus_context *)ctx;
538
539 if (ctx == fence->unflushed_ctx)
540 return;
541
542 for (unsigned b = 0; b < ice->batch_count; b++) {
543 for (unsigned i = 0; i < ARRAY_SIZE(fence->fine); i++) {
544 struct crocus_fine_fence *fine = fence->fine[i];
545
546 /* already signaled fence skipped */
547 if (crocus_fine_fence_signaled(fine))
548 continue;
549
550 ice->batches[b].contains_fence_signal = true;
551 crocus_batch_add_syncobj(&ice->batches[b], fine->syncobj,
552 I915_EXEC_FENCE_SIGNAL);
553 }
554 if (ice->batches[b].contains_fence_signal)
555 crocus_batch_flush(&ice->batches[b]);
556 }
557 }
558
559 void
crocus_init_screen_fence_functions(struct pipe_screen * screen)560 crocus_init_screen_fence_functions(struct pipe_screen *screen)
561 {
562 screen->fence_reference = crocus_fence_reference;
563 screen->fence_finish = crocus_fence_finish;
564 screen->fence_get_fd = crocus_fence_get_fd;
565 }
566
567 void
crocus_init_context_fence_functions(struct pipe_context * ctx)568 crocus_init_context_fence_functions(struct pipe_context *ctx)
569 {
570 ctx->flush = crocus_fence_flush;
571 ctx->create_fence_fd = crocus_fence_create_fd;
572 ctx->fence_server_sync = crocus_fence_await;
573 ctx->fence_server_signal = crocus_fence_signal;
574 }
575