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1// SPDX-License-Identifier: MIT2/*3 * Copyright © 2019 Intel Corporation4 */5 6#include "gem/i915_gem_context.h"7#include "gem/i915_gem_pm.h"8 9#include "i915_drm_client.h"10#include "i915_drv.h"11#include "i915_trace.h"12 13#include "intel_context.h"14#include "intel_engine.h"15#include "intel_engine_pm.h"16#include "intel_ring.h"17 18static struct kmem_cache *slab_ce;19 20static struct intel_context *intel_context_alloc(void)21{22 return kmem_cache_zalloc(slab_ce, GFP_KERNEL);23}24 25static void rcu_context_free(struct rcu_head *rcu)26{27 struct intel_context *ce = container_of(rcu, typeof(*ce), rcu);28 29 trace_intel_context_free(ce);30 if (intel_context_has_own_state(ce))31 fput(ce->default_state);32 kmem_cache_free(slab_ce, ce);33}34 35void intel_context_free(struct intel_context *ce)36{37 call_rcu(&ce->rcu, rcu_context_free);38}39 40struct intel_context *41intel_context_create(struct intel_engine_cs *engine)42{43 struct intel_context *ce;44 45 ce = intel_context_alloc();46 if (!ce)47 return ERR_PTR(-ENOMEM);48 49 intel_context_init(ce, engine);50 trace_intel_context_create(ce);51 return ce;52}53 54int intel_context_alloc_state(struct intel_context *ce)55{56 struct i915_gem_context *ctx;57 int err = 0;58 59 if (mutex_lock_interruptible(&ce->pin_mutex))60 return -EINTR;61 62 if (!test_bit(CONTEXT_ALLOC_BIT, &ce->flags)) {63 if (intel_context_is_banned(ce)) {64 err = -EIO;65 goto unlock;66 }67 68 err = ce->ops->alloc(ce);69 if (unlikely(err))70 goto unlock;71 72 set_bit(CONTEXT_ALLOC_BIT, &ce->flags);73 74 rcu_read_lock();75 ctx = rcu_dereference(ce->gem_context);76 if (ctx && !kref_get_unless_zero(&ctx->ref))77 ctx = NULL;78 rcu_read_unlock();79 if (ctx) {80 if (ctx->client)81 i915_drm_client_add_context_objects(ctx->client,82 ce);83 i915_gem_context_put(ctx);84 }85 }86 87unlock:88 mutex_unlock(&ce->pin_mutex);89 return err;90}91 92static int intel_context_active_acquire(struct intel_context *ce)93{94 int err;95 96 __i915_active_acquire(&ce->active);97 98 if (intel_context_is_barrier(ce) || intel_engine_uses_guc(ce->engine) ||99 intel_context_is_parallel(ce))100 return 0;101 102 /* Preallocate tracking nodes */103 err = i915_active_acquire_preallocate_barrier(&ce->active,104 ce->engine);105 if (err)106 i915_active_release(&ce->active);107 108 return err;109}110 111static void intel_context_active_release(struct intel_context *ce)112{113 /* Nodes preallocated in intel_context_active() */114 i915_active_acquire_barrier(&ce->active);115 i915_active_release(&ce->active);116}117 118static int __context_pin_state(struct i915_vma *vma, struct i915_gem_ww_ctx *ww)119{120 unsigned int bias = i915_ggtt_pin_bias(vma) | PIN_OFFSET_BIAS;121 int err;122 123 err = i915_ggtt_pin(vma, ww, 0, bias | PIN_HIGH);124 if (err)125 return err;126 127 err = i915_active_acquire(&vma->active);128 if (err)129 goto err_unpin;130 131 /*132 * And mark it as a globally pinned object to let the shrinker know133 * it cannot reclaim the object until we release it.134 */135 i915_vma_make_unshrinkable(vma);136 vma->obj->mm.dirty = true;137 138 return 0;139 140err_unpin:141 i915_vma_unpin(vma);142 return err;143}144 145static void __context_unpin_state(struct i915_vma *vma)146{147 i915_vma_make_shrinkable(vma);148 i915_active_release(&vma->active);149 __i915_vma_unpin(vma);150}151 152static int __ring_active(struct intel_ring *ring,153 struct i915_gem_ww_ctx *ww)154{155 int err;156 157 err = intel_ring_pin(ring, ww);158 if (err)159 return err;160 161 err = i915_active_acquire(&ring->vma->active);162 if (err)163 goto err_pin;164 165 return 0;166 167err_pin:168 intel_ring_unpin(ring);169 return err;170}171 172static void __ring_retire(struct intel_ring *ring)173{174 i915_active_release(&ring->vma->active);175 intel_ring_unpin(ring);176}177 178static int intel_context_pre_pin(struct intel_context *ce,179 struct i915_gem_ww_ctx *ww)180{181 int err;182 183 CE_TRACE(ce, "active\n");184 185 err = __ring_active(ce->ring, ww);186 if (err)187 return err;188 189 err = intel_timeline_pin(ce->timeline, ww);190 if (err)191 goto err_ring;192 193 if (!ce->state)194 return 0;195 196 err = __context_pin_state(ce->state, ww);197 if (err)198 goto err_timeline;199 200 201 return 0;202 203err_timeline:204 intel_timeline_unpin(ce->timeline);205err_ring:206 __ring_retire(ce->ring);207 return err;208}209 210static void intel_context_post_unpin(struct intel_context *ce)211{212 if (ce->state)213 __context_unpin_state(ce->state);214 215 intel_timeline_unpin(ce->timeline);216 __ring_retire(ce->ring);217}218 219int __intel_context_do_pin_ww(struct intel_context *ce,220 struct i915_gem_ww_ctx *ww)221{222 bool handoff = false;223 void *vaddr;224 int err = 0;225 226 if (unlikely(!test_bit(CONTEXT_ALLOC_BIT, &ce->flags))) {227 err = intel_context_alloc_state(ce);228 if (err)229 return err;230 }231 232 /*233 * We always pin the context/ring/timeline here, to ensure a pin234 * refcount for __intel_context_active(), which prevent a lock235 * inversion of ce->pin_mutex vs dma_resv_lock().236 */237 238 err = i915_gem_object_lock(ce->timeline->hwsp_ggtt->obj, ww);239 if (!err)240 err = i915_gem_object_lock(ce->ring->vma->obj, ww);241 if (!err && ce->state)242 err = i915_gem_object_lock(ce->state->obj, ww);243 if (!err)244 err = intel_context_pre_pin(ce, ww);245 if (err)246 return err;247 248 err = ce->ops->pre_pin(ce, ww, &vaddr);249 if (err)250 goto err_ctx_unpin;251 252 err = i915_active_acquire(&ce->active);253 if (err)254 goto err_post_unpin;255 256 err = mutex_lock_interruptible(&ce->pin_mutex);257 if (err)258 goto err_release;259 260 intel_engine_pm_might_get(ce->engine);261 262 if (unlikely(intel_context_is_closed(ce))) {263 err = -ENOENT;264 goto err_unlock;265 }266 267 if (likely(!atomic_add_unless(&ce->pin_count, 1, 0))) {268 err = intel_context_active_acquire(ce);269 if (unlikely(err))270 goto err_unlock;271 272 err = ce->ops->pin(ce, vaddr);273 if (err) {274 intel_context_active_release(ce);275 goto err_unlock;276 }277 278 CE_TRACE(ce, "pin ring:{start:%08x, head:%04x, tail:%04x}\n",279 i915_ggtt_offset(ce->ring->vma),280 ce->ring->head, ce->ring->tail);281 282 handoff = true;283 smp_mb__before_atomic(); /* flush pin before it is visible */284 atomic_inc(&ce->pin_count);285 }286 287 GEM_BUG_ON(!intel_context_is_pinned(ce)); /* no overflow! */288 289 trace_intel_context_do_pin(ce);290 291err_unlock:292 mutex_unlock(&ce->pin_mutex);293err_release:294 i915_active_release(&ce->active);295err_post_unpin:296 if (!handoff)297 ce->ops->post_unpin(ce);298err_ctx_unpin:299 intel_context_post_unpin(ce);300 301 /*302 * Unlock the hwsp_ggtt object since it's shared.303 * In principle we can unlock all the global state locked above304 * since it's pinned and doesn't need fencing, and will305 * thus remain resident until it is explicitly unpinned.306 */307 i915_gem_ww_unlock_single(ce->timeline->hwsp_ggtt->obj);308 309 return err;310}311 312int __intel_context_do_pin(struct intel_context *ce)313{314 struct i915_gem_ww_ctx ww;315 int err;316 317 i915_gem_ww_ctx_init(&ww, true);318retry:319 err = __intel_context_do_pin_ww(ce, &ww);320 if (err == -EDEADLK) {321 err = i915_gem_ww_ctx_backoff(&ww);322 if (!err)323 goto retry;324 }325 i915_gem_ww_ctx_fini(&ww);326 return err;327}328 329void __intel_context_do_unpin(struct intel_context *ce, int sub)330{331 if (!atomic_sub_and_test(sub, &ce->pin_count))332 return;333 334 CE_TRACE(ce, "unpin\n");335 ce->ops->unpin(ce);336 ce->ops->post_unpin(ce);337 338 /*339 * Once released, we may asynchronously drop the active reference.340 * As that may be the only reference keeping the context alive,341 * take an extra now so that it is not freed before we finish342 * dereferencing it.343 */344 intel_context_get(ce);345 intel_context_active_release(ce);346 trace_intel_context_do_unpin(ce);347 intel_context_put(ce);348}349 350static void __intel_context_retire(struct i915_active *active)351{352 struct intel_context *ce = container_of(active, typeof(*ce), active);353 354 CE_TRACE(ce, "retire runtime: { total:%lluns, avg:%lluns }\n",355 intel_context_get_total_runtime_ns(ce),356 intel_context_get_avg_runtime_ns(ce));357 358 set_bit(CONTEXT_VALID_BIT, &ce->flags);359 intel_context_post_unpin(ce);360 intel_context_put(ce);361}362 363static int __intel_context_active(struct i915_active *active)364{365 struct intel_context *ce = container_of(active, typeof(*ce), active);366 367 intel_context_get(ce);368 369 /* everything should already be activated by intel_context_pre_pin() */370 GEM_WARN_ON(!i915_active_acquire_if_busy(&ce->ring->vma->active));371 __intel_ring_pin(ce->ring);372 373 __intel_timeline_pin(ce->timeline);374 375 if (ce->state) {376 GEM_WARN_ON(!i915_active_acquire_if_busy(&ce->state->active));377 __i915_vma_pin(ce->state);378 i915_vma_make_unshrinkable(ce->state);379 }380 381 return 0;382}383 384static int385sw_fence_dummy_notify(struct i915_sw_fence *sf,386 enum i915_sw_fence_notify state)387{388 return NOTIFY_DONE;389}390 391void392intel_context_init(struct intel_context *ce, struct intel_engine_cs *engine)393{394 GEM_BUG_ON(!engine->cops);395 GEM_BUG_ON(!engine->gt->vm);396 397 kref_init(&ce->ref);398 399 ce->engine = engine;400 ce->ops = engine->cops;401 ce->sseu = engine->sseu;402 ce->ring = NULL;403 ce->ring_size = SZ_4K;404 405 ewma_runtime_init(&ce->stats.runtime.avg);406 407 ce->vm = i915_vm_get(engine->gt->vm);408 409 /* NB ce->signal_link/lock is used under RCU */410 spin_lock_init(&ce->signal_lock);411 INIT_LIST_HEAD(&ce->signals);412 413 mutex_init(&ce->pin_mutex);414 415 spin_lock_init(&ce->guc_state.lock);416 INIT_LIST_HEAD(&ce->guc_state.fences);417 INIT_LIST_HEAD(&ce->guc_state.requests);418 419 ce->guc_id.id = GUC_INVALID_CONTEXT_ID;420 INIT_LIST_HEAD(&ce->guc_id.link);421 422 INIT_LIST_HEAD(&ce->destroyed_link);423 424 INIT_LIST_HEAD(&ce->parallel.child_list);425 426 /*427 * Initialize fence to be complete as this is expected to be complete428 * unless there is a pending schedule disable outstanding.429 */430 i915_sw_fence_init(&ce->guc_state.blocked,431 sw_fence_dummy_notify);432 i915_sw_fence_commit(&ce->guc_state.blocked);433 434 i915_active_init(&ce->active,435 __intel_context_active, __intel_context_retire, 0);436}437 438void intel_context_fini(struct intel_context *ce)439{440 struct intel_context *child, *next;441 442 if (ce->timeline)443 intel_timeline_put(ce->timeline);444 i915_vm_put(ce->vm);445 446 /* Need to put the creation ref for the children */447 if (intel_context_is_parent(ce))448 for_each_child_safe(ce, child, next)449 intel_context_put(child);450 451 mutex_destroy(&ce->pin_mutex);452 i915_active_fini(&ce->active);453 i915_sw_fence_fini(&ce->guc_state.blocked);454}455 456void i915_context_module_exit(void)457{458 kmem_cache_destroy(slab_ce);459}460 461int __init i915_context_module_init(void)462{463 slab_ce = KMEM_CACHE(intel_context, SLAB_HWCACHE_ALIGN);464 if (!slab_ce)465 return -ENOMEM;466 467 return 0;468}469 470void intel_context_enter_engine(struct intel_context *ce)471{472 intel_engine_pm_get(ce->engine);473 intel_timeline_enter(ce->timeline);474}475 476void intel_context_exit_engine(struct intel_context *ce)477{478 intel_timeline_exit(ce->timeline);479 intel_engine_pm_put(ce->engine);480}481 482int intel_context_prepare_remote_request(struct intel_context *ce,483 struct i915_request *rq)484{485 struct intel_timeline *tl = ce->timeline;486 int err;487 488 /* Only suitable for use in remotely modifying this context */489 GEM_BUG_ON(rq->context == ce);490 491 if (rcu_access_pointer(rq->timeline) != tl) { /* timeline sharing! */492 /* Queue this switch after current activity by this context. */493 err = i915_active_fence_set(&tl->last_request, rq);494 if (err)495 return err;496 }497 498 /*499 * Guarantee context image and the timeline remains pinned until the500 * modifying request is retired by setting the ce activity tracker.501 *502 * But we only need to take one pin on the account of it. Or in other503 * words transfer the pinned ce object to tracked active request.504 */505 GEM_BUG_ON(i915_active_is_idle(&ce->active));506 return i915_active_add_request(&ce->active, rq);507}508 509struct i915_request *intel_context_create_request(struct intel_context *ce)510{511 struct i915_gem_ww_ctx ww;512 struct i915_request *rq;513 int err;514 515 i915_gem_ww_ctx_init(&ww, true);516retry:517 err = intel_context_pin_ww(ce, &ww);518 if (!err) {519 rq = i915_request_create(ce);520 intel_context_unpin(ce);521 } else if (err == -EDEADLK) {522 err = i915_gem_ww_ctx_backoff(&ww);523 if (!err)524 goto retry;525 rq = ERR_PTR(err);526 } else {527 rq = ERR_PTR(err);528 }529 530 i915_gem_ww_ctx_fini(&ww);531 532 if (IS_ERR(rq))533 return rq;534 535 /*536 * timeline->mutex should be the inner lock, but is used as outer lock.537 * Hack around this to shut up lockdep in selftests..538 */539 lockdep_unpin_lock(&ce->timeline->mutex, rq->cookie);540 mutex_release(&ce->timeline->mutex.dep_map, _RET_IP_);541 mutex_acquire(&ce->timeline->mutex.dep_map, SINGLE_DEPTH_NESTING, 0, _RET_IP_);542 rq->cookie = lockdep_pin_lock(&ce->timeline->mutex);543 544 return rq;545}546 547struct i915_request *intel_context_get_active_request(struct intel_context *ce)548{549 struct intel_context *parent = intel_context_to_parent(ce);550 struct i915_request *rq, *active = NULL;551 unsigned long flags;552 553 GEM_BUG_ON(!intel_engine_uses_guc(ce->engine));554 555 /*556 * We search the parent list to find an active request on the submitted557 * context. The parent list contains the requests for all the contexts558 * in the relationship so we have to do a compare of each request's559 * context.560 */561 spin_lock_irqsave(&parent->guc_state.lock, flags);562 list_for_each_entry_reverse(rq, &parent->guc_state.requests,563 sched.link) {564 if (rq->context != ce)565 continue;566 if (i915_request_completed(rq))567 break;568 569 active = rq;570 }571 if (active)572 active = i915_request_get_rcu(active);573 spin_unlock_irqrestore(&parent->guc_state.lock, flags);574 575 return active;576}577 578void intel_context_bind_parent_child(struct intel_context *parent,579 struct intel_context *child)580{581 /*582 * Callers responsibility to validate that this function is used583 * correctly but we use GEM_BUG_ON here ensure that they do.584 */585 GEM_BUG_ON(intel_context_is_pinned(parent));586 GEM_BUG_ON(intel_context_is_child(parent));587 GEM_BUG_ON(intel_context_is_pinned(child));588 GEM_BUG_ON(intel_context_is_child(child));589 GEM_BUG_ON(intel_context_is_parent(child));590 591 parent->parallel.child_index = parent->parallel.number_children++;592 list_add_tail(&child->parallel.child_link,593 &parent->parallel.child_list);594 child->parallel.parent = parent;595}596 597u64 intel_context_get_total_runtime_ns(struct intel_context *ce)598{599 u64 total, active;600 601 if (ce->ops->update_stats)602 ce->ops->update_stats(ce);603 604 total = ce->stats.runtime.total;605 if (ce->ops->flags & COPS_RUNTIME_CYCLES)606 total *= ce->engine->gt->clock_period_ns;607 608 active = READ_ONCE(ce->stats.active);609 if (active)610 active = intel_context_clock() - active;611 612 return total + active;613}614 615u64 intel_context_get_avg_runtime_ns(struct intel_context *ce)616{617 u64 avg = ewma_runtime_read(&ce->stats.runtime.avg);618 619 if (ce->ops->flags & COPS_RUNTIME_CYCLES)620 avg *= ce->engine->gt->clock_period_ns;621 622 return avg;623}624 625bool intel_context_ban(struct intel_context *ce, struct i915_request *rq)626{627 bool ret = intel_context_set_banned(ce);628 629 trace_intel_context_ban(ce);630 631 if (ce->ops->revoke)632 ce->ops->revoke(ce, rq,633 INTEL_CONTEXT_BANNED_PREEMPT_TIMEOUT_MS);634 635 return ret;636}637 638bool intel_context_revoke(struct intel_context *ce)639{640 bool ret = intel_context_set_exiting(ce);641 642 if (ce->ops->revoke)643 ce->ops->revoke(ce, NULL, ce->engine->props.preempt_timeout_ms);644 645 return ret;646}647 648#if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)649#include "selftest_context.c"650#endif651