[Intel-gfx] [PATCH 1/2] drm/i915/guc: Implement reset locally
Chris Wilson
chris at chris-wilson.co.uk
Mon Apr 8 22:38:56 UTC 2019
Before causing guc and execlists to diverge further (breaking guc in the
process), take a copy of the current reset procedure and make it local to
the guc submission backend
Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
---
drivers/gpu/drm/i915/intel_guc_submission.c | 102 ++++++++++++++++++++
drivers/gpu/drm/i915/intel_lrc.c | 37 ++++++-
drivers/gpu/drm/i915/intel_lrc.h | 5 +
drivers/gpu/drm/i915/intel_ringbuffer.h | 2 +-
4 files changed, 143 insertions(+), 3 deletions(-)
diff --git a/drivers/gpu/drm/i915/intel_guc_submission.c b/drivers/gpu/drm/i915/intel_guc_submission.c
index 42fcd622d7a3..6ebc125710ce 100644
--- a/drivers/gpu/drm/i915/intel_guc_submission.c
+++ b/drivers/gpu/drm/i915/intel_guc_submission.c
@@ -872,6 +872,104 @@ static void guc_reset_prepare(struct intel_engine_cs *engine)
flush_workqueue(engine->i915->guc.preempt_wq);
}
+static void guc_reset(struct intel_engine_cs *engine, bool stalled)
+{
+ struct intel_engine_execlists * const execlists = &engine->execlists;
+ struct i915_request *rq;
+ unsigned long flags;
+
+ spin_lock_irqsave(&engine->timeline.lock, flags);
+
+ execlists_cancel_port_requests(execlists);
+
+ /* Push back any incomplete requests for replay after the reset. */
+ rq = execlists_unwind_incomplete_requests(execlists);
+ if (!rq)
+ goto out_unlock;
+
+ if (!i915_request_started(rq))
+ stalled = false;
+
+ i915_reset_request(rq, stalled);
+ intel_lr_context_reset(engine, rq->hw_context, rq->head, stalled);
+
+out_unlock:
+ spin_unlock_irqrestore(&engine->timeline.lock, flags);
+}
+
+static void guc_cancel_requests(struct intel_engine_cs *engine)
+{
+ struct intel_engine_execlists * const execlists = &engine->execlists;
+ struct i915_request *rq, *rn;
+ struct rb_node *rb;
+ unsigned long flags;
+
+ GEM_TRACE("%s\n", engine->name);
+
+ /*
+ * Before we call engine->cancel_requests(), we should have exclusive
+ * access to the submission state. This is arranged for us by the
+ * caller disabling the interrupt generation, the tasklet and other
+ * threads that may then access the same state, giving us a free hand
+ * to reset state. However, we still need to let lockdep be aware that
+ * we know this state may be accessed in hardirq context, so we
+ * disable the irq around this manipulation and we want to keep
+ * the spinlock focused on its duties and not accidentally conflate
+ * coverage to the submission's irq state. (Similarly, although we
+ * shouldn't need to disable irq around the manipulation of the
+ * submission's irq state, we also wish to remind ourselves that
+ * it is irq state.)
+ */
+ spin_lock_irqsave(&engine->timeline.lock, flags);
+
+ /* Cancel the requests on the HW and clear the ELSP tracker. */
+ execlists_cancel_port_requests(execlists);
+
+ /* Mark all executing requests as skipped. */
+ list_for_each_entry(rq, &engine->timeline.requests, link) {
+ if (!i915_request_signaled(rq))
+ dma_fence_set_error(&rq->fence, -EIO);
+
+ i915_request_mark_complete(rq);
+ }
+
+ /* Flush the queued requests to the timeline list (for retiring). */
+ while ((rb = rb_first_cached(&execlists->queue))) {
+ struct i915_priolist *p = to_priolist(rb);
+ int i;
+
+ priolist_for_each_request_consume(rq, rn, p, i) {
+ list_del_init(&rq->sched.link);
+ __i915_request_submit(rq);
+ dma_fence_set_error(&rq->fence, -EIO);
+ i915_request_mark_complete(rq);
+ }
+
+ rb_erase_cached(&p->node, &execlists->queue);
+ i915_priolist_free(p);
+ }
+
+ /* Remaining _unready_ requests will be nop'ed when submitted */
+
+ execlists->queue_priority_hint = INT_MIN;
+ execlists->queue = RB_ROOT_CACHED;
+ GEM_BUG_ON(port_isset(execlists->port));
+
+ spin_unlock_irqrestore(&engine->timeline.lock, flags);
+}
+
+static void guc_reset_finish(struct intel_engine_cs *engine)
+{
+ struct intel_engine_execlists * const execlists = &engine->execlists;
+
+ if (__tasklet_enable(&execlists->tasklet))
+ /* And kick in case we missed a new request submission. */
+ tasklet_hi_schedule(&execlists->tasklet);
+
+ GEM_TRACE("%s: depth->%d\n", engine->name,
+ atomic_read(&execlists->tasklet.count));
+}
+
/*
* Everything below here is concerned with setup & teardown, and is
* therefore not part of the somewhat time-critical batch-submission
@@ -1293,6 +1391,10 @@ static void guc_set_default_submission(struct intel_engine_cs *engine)
engine->unpark = guc_submission_unpark;
engine->reset.prepare = guc_reset_prepare;
+ engine->reset.reset = guc_reset;
+ engine->reset.finish = guc_reset_finish;
+
+ engine->cancel_requests = guc_cancel_requests;
engine->flags &= ~I915_ENGINE_SUPPORTS_STATS;
}
diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c
index 6931dbb2888c..f096bc7bbe35 100644
--- a/drivers/gpu/drm/i915/intel_lrc.c
+++ b/drivers/gpu/drm/i915/intel_lrc.c
@@ -429,13 +429,13 @@ __unwind_incomplete_requests(struct intel_engine_cs *engine)
return active;
}
-void
+struct i915_request *
execlists_unwind_incomplete_requests(struct intel_engine_execlists *execlists)
{
struct intel_engine_cs *engine =
container_of(execlists, typeof(*engine), execlists);
- __unwind_incomplete_requests(engine);
+ return __unwind_incomplete_requests(engine);
}
static inline void
@@ -2328,6 +2328,8 @@ void intel_execlists_set_default_submission(struct intel_engine_cs *engine)
engine->execlists.tasklet.func = execlists_submission_tasklet;
engine->reset.prepare = execlists_reset_prepare;
+ engine->reset.reset = execlists_reset;
+ engine->reset.finish = execlists_reset_finish;
engine->park = NULL;
engine->unpark = NULL;
@@ -2980,6 +2982,37 @@ void intel_execlists_show_requests(struct intel_engine_cs *engine,
spin_unlock_irqrestore(&engine->timeline.lock, flags);
}
+void intel_lr_context_reset(struct intel_engine_cs *engine,
+ struct intel_context *ce,
+ u32 head,
+ bool scrub)
+{
+ /*
+ * We want a simple context + ring to execute the breadcrumb update.
+ * We cannot rely on the context being intact across the GPU hang,
+ * so clear it and rebuild just what we need for the breadcrumb.
+ * All pending requests for this context will be zapped, and any
+ * future request will be after userspace has had the opportunity
+ * to recreate its own state.
+ */
+ if (scrub) {
+ u32 *regs = ce->lrc_reg_state;
+
+ if (engine->pinned_default_state) {
+ memcpy(regs, /* skip restoring the vanilla PPHWSP */
+ engine->pinned_default_state + LRC_STATE_PN * PAGE_SIZE,
+ engine->context_size - PAGE_SIZE);
+ }
+ execlists_init_reg_state(regs, ce, engine, ce->ring);
+ }
+
+ /* Rerun the request; its payload has been neutered (if guilty). */
+ ce->ring->head = head;
+ intel_ring_update_space(ce->ring);
+
+ __execlists_update_reg_state(ce, engine);
+}
+
#if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
#include "selftests/intel_lrc.c"
#endif
diff --git a/drivers/gpu/drm/i915/intel_lrc.h b/drivers/gpu/drm/i915/intel_lrc.h
index 92642ab91472..5b20f1a9ea0f 100644
--- a/drivers/gpu/drm/i915/intel_lrc.h
+++ b/drivers/gpu/drm/i915/intel_lrc.h
@@ -105,6 +105,11 @@ struct i915_gem_context;
void intel_lr_context_resume(struct drm_i915_private *dev_priv);
void intel_execlists_set_default_submission(struct intel_engine_cs *engine);
+void intel_lr_context_reset(struct intel_engine_cs *engine,
+ struct intel_context *ce,
+ u32 head,
+ bool scrub);
+
void intel_execlists_show_requests(struct intel_engine_cs *engine,
struct drm_printer *m,
void (*show_request)(struct drm_printer *m,
diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.h b/drivers/gpu/drm/i915/intel_ringbuffer.h
index e58d6f04177b..bc1d7447a6cb 100644
--- a/drivers/gpu/drm/i915/intel_ringbuffer.h
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.h
@@ -165,7 +165,7 @@ void execlists_user_end(struct intel_engine_execlists *execlists);
void
execlists_cancel_port_requests(struct intel_engine_execlists * const execlists);
-void
+struct i915_request *
execlists_unwind_incomplete_requests(struct intel_engine_execlists *execlists);
static inline unsigned int
--
2.20.1
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