diff options
| -rw-r--r-- | drivers/gpu/drm/i915/gt/intel_lrc.c | 11 | ||||
| -rw-r--r-- | drivers/gpu/drm/i915/gt/selftest_lrc.c | 109 | ||||
| -rw-r--r-- | drivers/gpu/drm/i915/i915_priolist_types.h | 10 | ||||
| -rw-r--r-- | drivers/gpu/drm/i915/i915_request.c | 4 | ||||
| -rw-r--r-- | drivers/gpu/drm/i915/i915_request.h | 15 | ||||
| -rw-r--r-- | drivers/gpu/drm/i915/intel_guc_submission.c | 13 | ||||
| -rw-r--r-- | drivers/gpu/drm/i915/intel_pm.c | 5 |
7 files changed, 161 insertions, 6 deletions
diff --git a/drivers/gpu/drm/i915/gt/intel_lrc.c b/drivers/gpu/drm/i915/gt/intel_lrc.c index dec735405195..19ce8eb5e5c9 100644 --- a/drivers/gpu/drm/i915/gt/intel_lrc.c +++ b/drivers/gpu/drm/i915/gt/intel_lrc.c @@ -259,6 +259,17 @@ static int effective_prio(const struct i915_request *rq) int prio = rq_prio(rq); /* + * If this request is special and must not be interrupted at any + * cost, so be it. Note we are only checking the most recent request + * in the context and so may be masking an earlier vip request. It + * is hoped that under the conditions where nopreempt is used, this + * will not matter (i.e. all requests to that context will be + * nopreempt for as long as desired). + */ + if (i915_request_has_nopreempt(rq)) + prio = I915_PRIORITY_UNPREEMPTABLE; + + /* * On unwinding the active request, we give it a priority bump * if it has completed waiting on any semaphore. If we know that * the request has already started, we can prevent an unwanted diff --git a/drivers/gpu/drm/i915/gt/selftest_lrc.c b/drivers/gpu/drm/i915/gt/selftest_lrc.c index 672bdaa66540..b9b881ab8e7c 100644 --- a/drivers/gpu/drm/i915/gt/selftest_lrc.c +++ b/drivers/gpu/drm/i915/gt/selftest_lrc.c @@ -721,6 +721,114 @@ static void preempt_client_fini(struct preempt_client *c) kernel_context_close(c->ctx); } +static int live_nopreempt(void *arg) +{ + struct drm_i915_private *i915 = arg; + struct intel_engine_cs *engine; + struct preempt_client a, b; + enum intel_engine_id id; + intel_wakeref_t wakeref; + int err = -ENOMEM; + + /* + * Verify that we can disable preemption for an individual request + * that may be being observed and not want to be interrupted. + */ + + if (!HAS_LOGICAL_RING_PREEMPTION(i915)) + return 0; + + mutex_lock(&i915->drm.struct_mutex); + wakeref = intel_runtime_pm_get(&i915->runtime_pm); + + if (preempt_client_init(i915, &a)) + goto err_unlock; + if (preempt_client_init(i915, &b)) + goto err_client_a; + b.ctx->sched.priority = I915_USER_PRIORITY(I915_PRIORITY_MAX); + + for_each_engine(engine, i915, id) { + struct i915_request *rq_a, *rq_b; + + if (!intel_engine_has_preemption(engine)) + continue; + + engine->execlists.preempt_hang.count = 0; + + rq_a = igt_spinner_create_request(&a.spin, + a.ctx, engine, + MI_ARB_CHECK); + if (IS_ERR(rq_a)) { + err = PTR_ERR(rq_a); + goto err_client_b; + } + + /* Low priority client, but unpreemptable! */ + rq_a->flags |= I915_REQUEST_NOPREEMPT; + + i915_request_add(rq_a); + if (!igt_wait_for_spinner(&a.spin, rq_a)) { + pr_err("First client failed to start\n"); + goto err_wedged; + } + + rq_b = igt_spinner_create_request(&b.spin, + b.ctx, engine, + MI_ARB_CHECK); + if (IS_ERR(rq_b)) { + err = PTR_ERR(rq_b); + goto err_client_b; + } + + i915_request_add(rq_b); + + /* B is much more important than A! (But A is unpreemptable.) */ + GEM_BUG_ON(rq_prio(rq_b) <= rq_prio(rq_a)); + + /* Wait long enough for preemption and timeslicing */ + if (igt_wait_for_spinner(&b.spin, rq_b)) { + pr_err("Second client started too early!\n"); + goto err_wedged; + } + + igt_spinner_end(&a.spin); + + if (!igt_wait_for_spinner(&b.spin, rq_b)) { + pr_err("Second client failed to start\n"); + goto err_wedged; + } + + igt_spinner_end(&b.spin); + + if (engine->execlists.preempt_hang.count) { + pr_err("Preemption recorded x%d; should have been suppressed!\n", + engine->execlists.preempt_hang.count); + err = -EINVAL; + goto err_wedged; + } + + if (igt_flush_test(i915, I915_WAIT_LOCKED)) + goto err_wedged; + } + + err = 0; +err_client_b: + preempt_client_fini(&b); +err_client_a: + preempt_client_fini(&a); +err_unlock: + intel_runtime_pm_put(&i915->runtime_pm, wakeref); + mutex_unlock(&i915->drm.struct_mutex); + return err; + +err_wedged: + igt_spinner_end(&b.spin); + igt_spinner_end(&a.spin); + i915_gem_set_wedged(i915); + err = -EIO; + goto err_client_b; +} + static int live_suppress_self_preempt(void *arg) { struct drm_i915_private *i915 = arg; @@ -2028,6 +2136,7 @@ int intel_execlists_live_selftests(struct drm_i915_private *i915) SUBTEST(live_busywait_preempt), SUBTEST(live_preempt), SUBTEST(live_late_preempt), + SUBTEST(live_nopreempt), SUBTEST(live_suppress_self_preempt), SUBTEST(live_suppress_wait_preempt), SUBTEST(live_chain_preempt), diff --git a/drivers/gpu/drm/i915/i915_priolist_types.h b/drivers/gpu/drm/i915/i915_priolist_types.h index 49709de69875..b02dea17dcab 100644 --- a/drivers/gpu/drm/i915/i915_priolist_types.h +++ b/drivers/gpu/drm/i915/i915_priolist_types.h @@ -17,6 +17,16 @@ enum { I915_PRIORITY_NORMAL = I915_CONTEXT_DEFAULT_PRIORITY, I915_PRIORITY_MAX = I915_CONTEXT_MAX_USER_PRIORITY + 1, + /* + * Requests containing performance queries must not be preempted by + * another context. They get scheduled with their default priority and + * once they reach the execlist ports we ensure that they stick on the + * HW until finished by pretending that they have maximum priority, + * i.e. nothing can have higher priority and force us to usurp the + * active request. + */ + I915_PRIORITY_UNPREEMPTABLE = INT_MAX, + I915_PRIORITY_INVALID = INT_MIN }; diff --git a/drivers/gpu/drm/i915/i915_request.c b/drivers/gpu/drm/i915/i915_request.c index 5ff87c4a0cd5..222c9c56e9de 100644 --- a/drivers/gpu/drm/i915/i915_request.c +++ b/drivers/gpu/drm/i915/i915_request.c @@ -292,7 +292,7 @@ static bool i915_request_retire(struct i915_request *rq) dma_fence_signal_locked(&rq->fence); if (test_bit(DMA_FENCE_FLAG_ENABLE_SIGNAL_BIT, &rq->fence.flags)) i915_request_cancel_breadcrumb(rq); - if (rq->waitboost) { + if (i915_request_has_waitboost(rq)) { GEM_BUG_ON(!atomic_read(&rq->i915->gt_pm.rps.num_waiters)); atomic_dec(&rq->i915->gt_pm.rps.num_waiters); } @@ -684,7 +684,7 @@ __i915_request_create(struct intel_context *ce, gfp_t gfp) rq->file_priv = NULL; rq->batch = NULL; rq->capture_list = NULL; - rq->waitboost = false; + rq->flags = 0; rq->execution_mask = ALL_ENGINES; INIT_LIST_HEAD(&rq->active_list); diff --git a/drivers/gpu/drm/i915/i915_request.h b/drivers/gpu/drm/i915/i915_request.h index b58ceef92e20..313df3c37158 100644 --- a/drivers/gpu/drm/i915/i915_request.h +++ b/drivers/gpu/drm/i915/i915_request.h @@ -216,7 +216,9 @@ struct i915_request { /** Time at which this request was emitted, in jiffies. */ unsigned long emitted_jiffies; - bool waitboost; + unsigned long flags; +#define I915_REQUEST_WAITBOOST BIT(0) +#define I915_REQUEST_NOPREEMPT BIT(1) /** timeline->request entry for this request */ struct list_head link; @@ -430,6 +432,17 @@ static inline void i915_request_mark_complete(struct i915_request *rq) rq->hwsp_seqno = (u32 *)&rq->fence.seqno; /* decouple from HWSP */ } +static inline bool i915_request_has_waitboost(const struct i915_request *rq) +{ + return rq->flags & I915_REQUEST_WAITBOOST; +} + +static inline bool i915_request_has_nopreempt(const struct i915_request *rq) +{ + /* Preemption should only be disabled very rarely */ + return unlikely(rq->flags & I915_REQUEST_NOPREEMPT); +} + bool i915_retire_requests(struct drm_i915_private *i915); #endif /* I915_REQUEST_H */ diff --git a/drivers/gpu/drm/i915/intel_guc_submission.c b/drivers/gpu/drm/i915/intel_guc_submission.c index 12c22359fdac..f104b94c14ef 100644 --- a/drivers/gpu/drm/i915/intel_guc_submission.c +++ b/drivers/gpu/drm/i915/intel_guc_submission.c @@ -707,6 +707,16 @@ static inline int rq_prio(const struct i915_request *rq) return rq->sched.attr.priority | __NO_PREEMPTION; } +static inline int effective_prio(const struct i915_request *rq) +{ + int prio = rq_prio(rq); + + if (i915_request_has_nopreempt(rq)) + prio = I915_PRIORITY_UNPREEMPTABLE; + + return prio; +} + static struct i915_request *schedule_in(struct i915_request *rq, int idx) { trace_i915_request_in(rq, idx); @@ -747,7 +757,8 @@ static void __guc_dequeue(struct intel_engine_cs *engine) &engine->i915->guc.preempt_work[engine->id]; int prio = execlists->queue_priority_hint; - if (i915_scheduler_need_preempt(prio, rq_prio(last))) { + if (i915_scheduler_need_preempt(prio, + effective_prio(last))) { intel_write_status_page(engine, I915_GEM_HWS_PREEMPT, GUC_PREEMPT_INPROGRESS); diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c index 87244d8215a7..0cecea228546 100644 --- a/drivers/gpu/drm/i915/intel_pm.c +++ b/drivers/gpu/drm/i915/intel_pm.c @@ -6876,9 +6876,10 @@ void gen6_rps_boost(struct i915_request *rq) /* Serializes with i915_request_retire() */ boost = false; spin_lock_irqsave(&rq->lock, flags); - if (!rq->waitboost && !dma_fence_is_signaled_locked(&rq->fence)) { + if (!i915_request_has_waitboost(rq) && + !dma_fence_is_signaled_locked(&rq->fence)) { boost = !atomic_fetch_inc(&rps->num_waiters); - rq->waitboost = true; + rq->flags |= I915_REQUEST_WAITBOOST; } spin_unlock_irqrestore(&rq->lock, flags); if (!boost) |