1 /* 2 * Copyright © 2008-2015 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 */ 24 25 #ifndef I915_GEM_REQUEST_H 26 #define I915_GEM_REQUEST_H 27 28 #include <linux/dma-fence.h> 29 30 #include "i915_gem.h" 31 #include "i915_sw_fence.h" 32 33 struct drm_file; 34 struct drm_i915_gem_object; 35 36 struct intel_wait { 37 struct rb_node node; 38 struct task_struct *tsk; 39 u32 seqno; 40 }; 41 42 struct intel_signal_node { 43 struct rb_node node; 44 struct intel_wait wait; 45 }; 46 47 struct i915_dependency { 48 struct i915_priotree *signaler; 49 struct list_head signal_link; 50 struct list_head wait_link; 51 struct list_head dfs_link; 52 unsigned long flags; 53 #define I915_DEPENDENCY_ALLOC BIT(0) 54 }; 55 56 /* Requests exist in a complex web of interdependencies. Each request 57 * has to wait for some other request to complete before it is ready to be run 58 * (e.g. we have to wait until the pixels have been rendering into a texture 59 * before we can copy from it). We track the readiness of a request in terms 60 * of fences, but we also need to keep the dependency tree for the lifetime 61 * of the request (beyond the life of an individual fence). We use the tree 62 * at various points to reorder the requests whilst keeping the requests 63 * in order with respect to their various dependencies. 64 */ 65 struct i915_priotree { 66 struct list_head signalers_list; /* those before us, we depend upon */ 67 struct list_head waiters_list; /* those after us, they depend upon us */ 68 struct rb_node node; 69 int priority; 70 #define I915_PRIORITY_MAX 1024 71 #define I915_PRIORITY_MIN (-I915_PRIORITY_MAX) 72 }; 73 74 /** 75 * Request queue structure. 76 * 77 * The request queue allows us to note sequence numbers that have been emitted 78 * and may be associated with active buffers to be retired. 79 * 80 * By keeping this list, we can avoid having to do questionable sequence 81 * number comparisons on buffer last_read|write_seqno. It also allows an 82 * emission time to be associated with the request for tracking how far ahead 83 * of the GPU the submission is. 84 * 85 * When modifying this structure be very aware that we perform a lockless 86 * RCU lookup of it that may race against reallocation of the struct 87 * from the slab freelist. We intentionally do not zero the structure on 88 * allocation so that the lookup can use the dangling pointers (and is 89 * cogniscent that those pointers may be wrong). Instead, everything that 90 * needs to be initialised must be done so explicitly. 91 * 92 * The requests are reference counted. 93 */ 94 struct drm_i915_gem_request { 95 struct dma_fence fence; 96 spinlock_t lock; 97 98 /** On Which ring this request was generated */ 99 struct drm_i915_private *i915; 100 101 /** 102 * Context and ring buffer related to this request 103 * Contexts are refcounted, so when this request is associated with a 104 * context, we must increment the context's refcount, to guarantee that 105 * it persists while any request is linked to it. Requests themselves 106 * are also refcounted, so the request will only be freed when the last 107 * reference to it is dismissed, and the code in 108 * i915_gem_request_free() will then decrement the refcount on the 109 * context. 110 */ 111 struct i915_gem_context *ctx; 112 struct intel_engine_cs *engine; 113 struct intel_ring *ring; 114 struct intel_timeline *timeline; 115 struct intel_signal_node signaling; 116 117 /* Fences for the various phases in the request's lifetime. 118 * 119 * The submit fence is used to await upon all of the request's 120 * dependencies. When it is signaled, the request is ready to run. 121 * It is used by the driver to then queue the request for execution. 122 * 123 * The execute fence is used to signal when the request has been 124 * sent to hardware. 125 * 126 * It is illegal for the submit fence of one request to wait upon the 127 * execute fence of an earlier request. It should be sufficient to 128 * wait upon the submit fence of the earlier request. 129 */ 130 struct i915_sw_fence submit; 131 struct i915_sw_fence execute; 132 wait_queue_t submitq; 133 wait_queue_t execq; 134 135 /* A list of everyone we wait upon, and everyone who waits upon us. 136 * Even though we will not be submitted to the hardware before the 137 * submit fence is signaled (it waits for all external events as well 138 * as our own requests), the scheduler still needs to know the 139 * dependency tree for the lifetime of the request (from execbuf 140 * to retirement), i.e. bidirectional dependency information for the 141 * request not tied to individual fences. 142 */ 143 struct i915_priotree priotree; 144 struct i915_dependency dep; 145 146 u32 global_seqno; 147 148 /** GEM sequence number associated with the previous request, 149 * when the HWS breadcrumb is equal to this the GPU is processing 150 * this request. 151 */ 152 u32 previous_seqno; 153 154 /** Position in the ring of the start of the request */ 155 u32 head; 156 157 /** 158 * Position in the ring of the start of the postfix. 159 * This is required to calculate the maximum available ring space 160 * without overwriting the postfix. 161 */ 162 u32 postfix; 163 164 /** Position in the ring of the end of the whole request */ 165 u32 tail; 166 167 /** Position in the ring of the end of any workarounds after the tail */ 168 u32 wa_tail; 169 170 /** Preallocate space in the ring for the emitting the request */ 171 u32 reserved_space; 172 173 /** 174 * Context related to the previous request. 175 * As the contexts are accessed by the hardware until the switch is 176 * completed to a new context, the hardware may still be writing 177 * to the context object after the breadcrumb is visible. We must 178 * not unpin/unbind/prune that object whilst still active and so 179 * we keep the previous context pinned until the following (this) 180 * request is retired. 181 */ 182 struct i915_gem_context *previous_context; 183 184 /** Batch buffer related to this request if any (used for 185 * error state dump only). 186 */ 187 struct i915_vma *batch; 188 struct list_head active_list; 189 190 /** Time at which this request was emitted, in jiffies. */ 191 unsigned long emitted_jiffies; 192 193 /** engine->request_list entry for this request */ 194 struct list_head link; 195 196 /** ring->request_list entry for this request */ 197 struct list_head ring_link; 198 199 struct drm_i915_file_private *file_priv; 200 /** file_priv list entry for this request */ 201 struct list_head client_list; 202 }; 203 204 extern const struct dma_fence_ops i915_fence_ops; 205 206 static inline bool dma_fence_is_i915(const struct dma_fence *fence) 207 { 208 return fence->ops == &i915_fence_ops; 209 } 210 211 struct drm_i915_gem_request * __must_check 212 i915_gem_request_alloc(struct intel_engine_cs *engine, 213 struct i915_gem_context *ctx); 214 int i915_gem_request_add_to_client(struct drm_i915_gem_request *req, 215 struct drm_file *file); 216 void i915_gem_request_retire_upto(struct drm_i915_gem_request *req); 217 218 static inline struct drm_i915_gem_request * 219 to_request(struct dma_fence *fence) 220 { 221 /* We assume that NULL fence/request are interoperable */ 222 BUILD_BUG_ON(offsetof(struct drm_i915_gem_request, fence) != 0); 223 GEM_BUG_ON(fence && !dma_fence_is_i915(fence)); 224 return container_of(fence, struct drm_i915_gem_request, fence); 225 } 226 227 static inline struct drm_i915_gem_request * 228 i915_gem_request_get(struct drm_i915_gem_request *req) 229 { 230 return to_request(dma_fence_get(&req->fence)); 231 } 232 233 static inline struct drm_i915_gem_request * 234 i915_gem_request_get_rcu(struct drm_i915_gem_request *req) 235 { 236 return to_request(dma_fence_get_rcu(&req->fence)); 237 } 238 239 static inline void 240 i915_gem_request_put(struct drm_i915_gem_request *req) 241 { 242 dma_fence_put(&req->fence); 243 } 244 245 static inline void i915_gem_request_assign(struct drm_i915_gem_request **pdst, 246 struct drm_i915_gem_request *src) 247 { 248 if (src) 249 i915_gem_request_get(src); 250 251 if (*pdst) 252 i915_gem_request_put(*pdst); 253 254 *pdst = src; 255 } 256 257 int 258 i915_gem_request_await_object(struct drm_i915_gem_request *to, 259 struct drm_i915_gem_object *obj, 260 bool write); 261 int i915_gem_request_await_dma_fence(struct drm_i915_gem_request *req, 262 struct dma_fence *fence); 263 264 void __i915_add_request(struct drm_i915_gem_request *req, bool flush_caches); 265 #define i915_add_request(req) \ 266 __i915_add_request(req, true) 267 #define i915_add_request_no_flush(req) \ 268 __i915_add_request(req, false) 269 270 void __i915_gem_request_submit(struct drm_i915_gem_request *request); 271 void i915_gem_request_submit(struct drm_i915_gem_request *request); 272 273 struct intel_rps_client; 274 #define NO_WAITBOOST ERR_PTR(-1) 275 #define IS_RPS_CLIENT(p) (!IS_ERR(p)) 276 #define IS_RPS_USER(p) (!IS_ERR_OR_NULL(p)) 277 278 long i915_wait_request(struct drm_i915_gem_request *req, 279 unsigned int flags, 280 long timeout) 281 __attribute__((nonnull(1))); 282 #define I915_WAIT_INTERRUPTIBLE BIT(0) 283 #define I915_WAIT_LOCKED BIT(1) /* struct_mutex held, handle GPU reset */ 284 #define I915_WAIT_ALL BIT(2) /* used by i915_gem_object_wait() */ 285 286 static inline u32 intel_engine_get_seqno(struct intel_engine_cs *engine); 287 288 /** 289 * Returns true if seq1 is later than seq2. 290 */ 291 static inline bool i915_seqno_passed(u32 seq1, u32 seq2) 292 { 293 return (s32)(seq1 - seq2) >= 0; 294 } 295 296 static inline bool 297 __i915_gem_request_started(const struct drm_i915_gem_request *req) 298 { 299 GEM_BUG_ON(!req->global_seqno); 300 return i915_seqno_passed(intel_engine_get_seqno(req->engine), 301 req->previous_seqno); 302 } 303 304 static inline bool 305 i915_gem_request_started(const struct drm_i915_gem_request *req) 306 { 307 if (!req->global_seqno) 308 return false; 309 310 return __i915_gem_request_started(req); 311 } 312 313 static inline bool 314 __i915_gem_request_completed(const struct drm_i915_gem_request *req) 315 { 316 GEM_BUG_ON(!req->global_seqno); 317 return i915_seqno_passed(intel_engine_get_seqno(req->engine), 318 req->global_seqno); 319 } 320 321 static inline bool 322 i915_gem_request_completed(const struct drm_i915_gem_request *req) 323 { 324 if (!req->global_seqno) 325 return false; 326 327 return __i915_gem_request_completed(req); 328 } 329 330 bool __i915_spin_request(const struct drm_i915_gem_request *request, 331 int state, unsigned long timeout_us); 332 static inline bool i915_spin_request(const struct drm_i915_gem_request *request, 333 int state, unsigned long timeout_us) 334 { 335 return (__i915_gem_request_started(request) && 336 __i915_spin_request(request, state, timeout_us)); 337 } 338 339 /* We treat requests as fences. This is not be to confused with our 340 * "fence registers" but pipeline synchronisation objects ala GL_ARB_sync. 341 * We use the fences to synchronize access from the CPU with activity on the 342 * GPU, for example, we should not rewrite an object's PTE whilst the GPU 343 * is reading them. We also track fences at a higher level to provide 344 * implicit synchronisation around GEM objects, e.g. set-domain will wait 345 * for outstanding GPU rendering before marking the object ready for CPU 346 * access, or a pageflip will wait until the GPU is complete before showing 347 * the frame on the scanout. 348 * 349 * In order to use a fence, the object must track the fence it needs to 350 * serialise with. For example, GEM objects want to track both read and 351 * write access so that we can perform concurrent read operations between 352 * the CPU and GPU engines, as well as waiting for all rendering to 353 * complete, or waiting for the last GPU user of a "fence register". The 354 * object then embeds a #i915_gem_active to track the most recent (in 355 * retirement order) request relevant for the desired mode of access. 356 * The #i915_gem_active is updated with i915_gem_active_set() to track the 357 * most recent fence request, typically this is done as part of 358 * i915_vma_move_to_active(). 359 * 360 * When the #i915_gem_active completes (is retired), it will 361 * signal its completion to the owner through a callback as well as mark 362 * itself as idle (i915_gem_active.request == NULL). The owner 363 * can then perform any action, such as delayed freeing of an active 364 * resource including itself. 365 */ 366 struct i915_gem_active; 367 368 typedef void (*i915_gem_retire_fn)(struct i915_gem_active *, 369 struct drm_i915_gem_request *); 370 371 struct i915_gem_active { 372 struct drm_i915_gem_request __rcu *request; 373 struct list_head link; 374 i915_gem_retire_fn retire; 375 }; 376 377 void i915_gem_retire_noop(struct i915_gem_active *, 378 struct drm_i915_gem_request *request); 379 380 /** 381 * init_request_active - prepares the activity tracker for use 382 * @active - the active tracker 383 * @func - a callback when then the tracker is retired (becomes idle), 384 * can be NULL 385 * 386 * init_request_active() prepares the embedded @active struct for use as 387 * an activity tracker, that is for tracking the last known active request 388 * associated with it. When the last request becomes idle, when it is retired 389 * after completion, the optional callback @func is invoked. 390 */ 391 static inline void 392 init_request_active(struct i915_gem_active *active, 393 i915_gem_retire_fn retire) 394 { 395 INIT_LIST_HEAD(&active->link); 396 active->retire = retire ?: i915_gem_retire_noop; 397 } 398 399 /** 400 * i915_gem_active_set - updates the tracker to watch the current request 401 * @active - the active tracker 402 * @request - the request to watch 403 * 404 * i915_gem_active_set() watches the given @request for completion. Whilst 405 * that @request is busy, the @active reports busy. When that @request is 406 * retired, the @active tracker is updated to report idle. 407 */ 408 static inline void 409 i915_gem_active_set(struct i915_gem_active *active, 410 struct drm_i915_gem_request *request) 411 { 412 list_move(&active->link, &request->active_list); 413 rcu_assign_pointer(active->request, request); 414 } 415 416 /** 417 * i915_gem_active_set_retire_fn - updates the retirement callback 418 * @active - the active tracker 419 * @fn - the routine called when the request is retired 420 * @mutex - struct_mutex used to guard retirements 421 * 422 * i915_gem_active_set_retire_fn() updates the function pointer that 423 * is called when the final request associated with the @active tracker 424 * is retired. 425 */ 426 static inline void 427 i915_gem_active_set_retire_fn(struct i915_gem_active *active, 428 i915_gem_retire_fn fn, 429 struct lock *mutex) 430 { 431 lockdep_assert_held(mutex); 432 active->retire = fn ?: i915_gem_retire_noop; 433 } 434 435 static inline struct drm_i915_gem_request * 436 __i915_gem_active_peek(const struct i915_gem_active *active) 437 { 438 /* Inside the error capture (running with the driver in an unknown 439 * state), we want to bend the rules slightly (a lot). 440 * 441 * Work is in progress to make it safer, in the meantime this keeps 442 * the known issue from spamming the logs. 443 */ 444 return rcu_dereference_protected(active->request, 1); 445 } 446 447 /** 448 * i915_gem_active_raw - return the active request 449 * @active - the active tracker 450 * 451 * i915_gem_active_raw() returns the current request being tracked, or NULL. 452 * It does not obtain a reference on the request for the caller, so the caller 453 * must hold struct_mutex. 454 */ 455 static inline struct drm_i915_gem_request * 456 i915_gem_active_raw(const struct i915_gem_active *active, struct lock *mutex) 457 { 458 return rcu_dereference_protected(active->request, 459 lockdep_is_held(mutex)); 460 } 461 462 /** 463 * i915_gem_active_peek - report the active request being monitored 464 * @active - the active tracker 465 * 466 * i915_gem_active_peek() returns the current request being tracked if 467 * still active, or NULL. It does not obtain a reference on the request 468 * for the caller, so the caller must hold struct_mutex. 469 */ 470 static inline struct drm_i915_gem_request * 471 i915_gem_active_peek(const struct i915_gem_active *active, struct lock *mutex) 472 { 473 struct drm_i915_gem_request *request; 474 475 request = i915_gem_active_raw(active, mutex); 476 if (!request || i915_gem_request_completed(request)) 477 return NULL; 478 479 return request; 480 } 481 482 /** 483 * i915_gem_active_get - return a reference to the active request 484 * @active - the active tracker 485 * 486 * i915_gem_active_get() returns a reference to the active request, or NULL 487 * if the active tracker is idle. The caller must hold struct_mutex. 488 */ 489 static inline struct drm_i915_gem_request * 490 i915_gem_active_get(const struct i915_gem_active *active, struct lock *mutex) 491 { 492 return i915_gem_request_get(i915_gem_active_peek(active, mutex)); 493 } 494 495 /** 496 * __i915_gem_active_get_rcu - return a reference to the active request 497 * @active - the active tracker 498 * 499 * __i915_gem_active_get() returns a reference to the active request, or NULL 500 * if the active tracker is idle. The caller must hold the RCU read lock, but 501 * the returned pointer is safe to use outside of RCU. 502 */ 503 static inline struct drm_i915_gem_request * 504 __i915_gem_active_get_rcu(const struct i915_gem_active *active) 505 { 506 /* Performing a lockless retrieval of the active request is super 507 * tricky. SLAB_DESTROY_BY_RCU merely guarantees that the backing 508 * slab of request objects will not be freed whilst we hold the 509 * RCU read lock. It does not guarantee that the request itself 510 * will not be freed and then *reused*. Viz, 511 * 512 * Thread A Thread B 513 * 514 * req = active.request 515 * retire(req) -> free(req); 516 * (req is now first on the slab freelist) 517 * active.request = NULL 518 * 519 * req = new submission on a new object 520 * ref(req) 521 * 522 * To prevent the request from being reused whilst the caller 523 * uses it, we take a reference like normal. Whilst acquiring 524 * the reference we check that it is not in a destroyed state 525 * (refcnt == 0). That prevents the request being reallocated 526 * whilst the caller holds on to it. To check that the request 527 * was not reallocated as we acquired the reference we have to 528 * check that our request remains the active request across 529 * the lookup, in the same manner as a seqlock. The visibility 530 * of the pointer versus the reference counting is controlled 531 * by using RCU barriers (rcu_dereference and rcu_assign_pointer). 532 * 533 * In the middle of all that, we inspect whether the request is 534 * complete. Retiring is lazy so the request may be completed long 535 * before the active tracker is updated. Querying whether the 536 * request is complete is far cheaper (as it involves no locked 537 * instructions setting cachelines to exclusive) than acquiring 538 * the reference, so we do it first. The RCU read lock ensures the 539 * pointer dereference is valid, but does not ensure that the 540 * seqno nor HWS is the right one! However, if the request was 541 * reallocated, that means the active tracker's request was complete. 542 * If the new request is also complete, then both are and we can 543 * just report the active tracker is idle. If the new request is 544 * incomplete, then we acquire a reference on it and check that 545 * it remained the active request. 546 * 547 * It is then imperative that we do not zero the request on 548 * reallocation, so that we can chase the dangling pointers! 549 * See i915_gem_request_alloc(). 550 */ 551 do { 552 struct drm_i915_gem_request *request; 553 554 request = rcu_dereference(active->request); 555 if (!request || i915_gem_request_completed(request)) 556 return NULL; 557 558 /* An especially silly compiler could decide to recompute the 559 * result of i915_gem_request_completed, more specifically 560 * re-emit the load for request->fence.seqno. A race would catch 561 * a later seqno value, which could flip the result from true to 562 * false. Which means part of the instructions below might not 563 * be executed, while later on instructions are executed. Due to 564 * barriers within the refcounting the inconsistency can't reach 565 * past the call to i915_gem_request_get_rcu, but not executing 566 * that while still executing i915_gem_request_put() creates 567 * havoc enough. Prevent this with a compiler barrier. 568 */ 569 barrier(); 570 571 request = i915_gem_request_get_rcu(request); 572 573 /* What stops the following rcu_access_pointer() from occurring 574 * before the above i915_gem_request_get_rcu()? If we were 575 * to read the value before pausing to get the reference to 576 * the request, we may not notice a change in the active 577 * tracker. 578 * 579 * The rcu_access_pointer() is a mere compiler barrier, which 580 * means both the CPU and compiler are free to perform the 581 * memory read without constraint. The compiler only has to 582 * ensure that any operations after the rcu_access_pointer() 583 * occur afterwards in program order. This means the read may 584 * be performed earlier by an out-of-order CPU, or adventurous 585 * compiler. 586 * 587 * The atomic operation at the heart of 588 * i915_gem_request_get_rcu(), see dma_fence_get_rcu(), is 589 * atomic_inc_not_zero() which is only a full memory barrier 590 * when successful. That is, if i915_gem_request_get_rcu() 591 * returns the request (and so with the reference counted 592 * incremented) then the following read for rcu_access_pointer() 593 * must occur after the atomic operation and so confirm 594 * that this request is the one currently being tracked. 595 * 596 * The corresponding write barrier is part of 597 * rcu_assign_pointer(). 598 */ 599 if (!request || request == rcu_access_pointer(active->request)) 600 return rcu_pointer_handoff(request); 601 602 i915_gem_request_put(request); 603 } while (1); 604 } 605 606 /** 607 * i915_gem_active_get_unlocked - return a reference to the active request 608 * @active - the active tracker 609 * 610 * i915_gem_active_get_unlocked() returns a reference to the active request, 611 * or NULL if the active tracker is idle. The reference is obtained under RCU, 612 * so no locking is required by the caller. 613 * 614 * The reference should be freed with i915_gem_request_put(). 615 */ 616 static inline struct drm_i915_gem_request * 617 i915_gem_active_get_unlocked(const struct i915_gem_active *active) 618 { 619 struct drm_i915_gem_request *request; 620 621 rcu_read_lock(); 622 request = __i915_gem_active_get_rcu(active); 623 rcu_read_unlock(); 624 625 return request; 626 } 627 628 /** 629 * i915_gem_active_isset - report whether the active tracker is assigned 630 * @active - the active tracker 631 * 632 * i915_gem_active_isset() returns true if the active tracker is currently 633 * assigned to a request. Due to the lazy retiring, that request may be idle 634 * and this may report stale information. 635 */ 636 static inline bool 637 i915_gem_active_isset(const struct i915_gem_active *active) 638 { 639 return rcu_access_pointer(active->request); 640 } 641 642 /** 643 * i915_gem_active_wait - waits until the request is completed 644 * @active - the active request on which to wait 645 * @flags - how to wait 646 * @timeout - how long to wait at most 647 * @rps - userspace client to charge for a waitboost 648 * 649 * i915_gem_active_wait() waits until the request is completed before 650 * returning, without requiring any locks to be held. Note that it does not 651 * retire any requests before returning. 652 * 653 * This function relies on RCU in order to acquire the reference to the active 654 * request without holding any locks. See __i915_gem_active_get_rcu() for the 655 * glory details on how that is managed. Once the reference is acquired, we 656 * can then wait upon the request, and afterwards release our reference, 657 * free of any locking. 658 * 659 * This function wraps i915_wait_request(), see it for the full details on 660 * the arguments. 661 * 662 * Returns 0 if successful, or a negative error code. 663 */ 664 static inline int 665 i915_gem_active_wait(const struct i915_gem_active *active, unsigned int flags) 666 { 667 struct drm_i915_gem_request *request; 668 long ret = 0; 669 670 request = i915_gem_active_get_unlocked(active); 671 if (request) { 672 ret = i915_wait_request(request, flags, MAX_SCHEDULE_TIMEOUT); 673 i915_gem_request_put(request); 674 } 675 676 return ret < 0 ? ret : 0; 677 } 678 679 /** 680 * i915_gem_active_retire - waits until the request is retired 681 * @active - the active request on which to wait 682 * 683 * i915_gem_active_retire() waits until the request is completed, 684 * and then ensures that at least the retirement handler for this 685 * @active tracker is called before returning. If the @active 686 * tracker is idle, the function returns immediately. 687 */ 688 static inline int __must_check 689 i915_gem_active_retire(struct i915_gem_active *active, 690 struct lock *mutex) 691 { 692 struct drm_i915_gem_request *request; 693 long ret; 694 695 request = i915_gem_active_raw(active, mutex); 696 if (!request) 697 return 0; 698 699 ret = i915_wait_request(request, 700 I915_WAIT_INTERRUPTIBLE | I915_WAIT_LOCKED, 701 MAX_SCHEDULE_TIMEOUT); 702 if (ret < 0) 703 return ret; 704 705 list_del_init(&active->link); 706 RCU_INIT_POINTER(active->request, NULL); 707 708 active->retire(active, request); 709 710 return 0; 711 } 712 713 #define for_each_active(mask, idx) \ 714 for (; mask ? idx = ffs(mask) - 1, 1 : 0; mask &= ~BIT(idx)) 715 716 #endif /* I915_GEM_REQUEST_H */ 717