[PATCH v2] drm/i915/gt: Reset all pinned contexts at __engine_unpark()

[Thomas Hellström]

Don't just reset the kernel context but include all other pinned contexts
as well. Currently this affects the migrate pinned contexts.

Signed-off-by: Thomas Hellström <thomas.hellstrom at linux.intel.com>
---
 drivers/gpu/drm/i915/gt/intel_context_types.h | 8 ++++++++
 drivers/gpu/drm/i915/gt/intel_engine_cs.c     | 4 ++++
 drivers/gpu/drm/i915/gt/intel_engine_pm.c     | 8 +++++---
 drivers/gpu/drm/i915/gt/intel_engine_types.h  | 7 +++++++
 4 files changed, 24 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/i915/gt/intel_context_types.h b/drivers/gpu/drm/i915/gt/intel_context_types.h
index e54351a170e2..a63631ea0ec4 100644
--- a/drivers/gpu/drm/i915/gt/intel_context_types.h
+++ b/drivers/gpu/drm/i915/gt/intel_context_types.h
@@ -152,6 +152,14 @@ struct intel_context {
 	/** sseu: Control eu/slice partitioning */
 	struct intel_sseu sseu;
 
+	/**
+	 * pinned_contexts_link: List link for the engine's pinned contexts.
+	 * This is only used if this is a perma-pinned kernel context and
+	 * the list is assumed to only be manipulated during driver load
+	 * or unload time so no mutex protection currently.
+	 */
+	struct list_head pinned_contexts_link;
+
 	u8 wa_bb_page; /* if set, page num reserved for context workarounds */
 
 	struct {
diff --git a/drivers/gpu/drm/i915/gt/intel_engine_cs.c b/drivers/gpu/drm/i915/gt/intel_engine_cs.c
index 332efea696a5..c606a4714904 100644
--- a/drivers/gpu/drm/i915/gt/intel_engine_cs.c
+++ b/drivers/gpu/drm/i915/gt/intel_engine_cs.c
@@ -320,6 +320,7 @@ static int intel_engine_setup(struct intel_gt *gt, enum intel_engine_id id)
 
 	BUILD_BUG_ON(BITS_PER_TYPE(engine->mask) < I915_NUM_ENGINES);
 
+	INIT_LIST_HEAD(&engine->pinned_contexts_list);
 	engine->id = id;
 	engine->legacy_idx = INVALID_ENGINE;
 	engine->mask = BIT(id);
@@ -875,6 +876,8 @@ intel_engine_create_pinned_context(struct intel_engine_cs *engine,
 		return ERR_PTR(err);
 	}
 
+	list_add_tail(&ce->pinned_contexts_link, &engine->pinned_contexts_list);
+
 	/*
 	 * Give our perma-pinned kernel timelines a separate lockdep class,
 	 * so that we can use them from within the normal user timelines
@@ -897,6 +900,7 @@ void intel_engine_destroy_pinned_context(struct intel_context *ce)
 	list_del(&ce->timeline->engine_link);
 	mutex_unlock(&hwsp->vm->mutex);
 
+	list_del(&ce->pinned_contexts_link);
 	intel_context_unpin(ce);
 	intel_context_put(ce);
 }
diff --git a/drivers/gpu/drm/i915/gt/intel_engine_pm.c b/drivers/gpu/drm/i915/gt/intel_engine_pm.c
index 1f07ac4e0672..ff728a7ffd28 100644
--- a/drivers/gpu/drm/i915/gt/intel_engine_pm.c
+++ b/drivers/gpu/drm/i915/gt/intel_engine_pm.c
@@ -50,9 +50,11 @@ static int __engine_unpark(struct intel_wakeref *wf)
 	intel_gt_pm_get(engine->gt);
 
 	/* Discard stale context state from across idling */
-	ce = engine->kernel_context;
-	if (ce) {
-		GEM_BUG_ON(test_bit(CONTEXT_VALID_BIT, &ce->flags));
+	list_for_each_entry(ce, &engine->pinned_contexts_list,
+			    pinned_contexts_link) {
+
+		GEM_BUG_ON(ce == engine->kernel_context &&
+			   test_bit(CONTEXT_VALID_BIT, &ce->flags));
 
 		/* Flush all pending HW writes before we touch the context */
 		while (unlikely(intel_context_inflight(ce)))
diff --git a/drivers/gpu/drm/i915/gt/intel_engine_types.h b/drivers/gpu/drm/i915/gt/intel_engine_types.h
index bfbfe53c23dd..5ae1207c363b 100644
--- a/drivers/gpu/drm/i915/gt/intel_engine_types.h
+++ b/drivers/gpu/drm/i915/gt/intel_engine_types.h
@@ -307,6 +307,13 @@ struct intel_engine_cs {
 
 	struct intel_context *kernel_context; /* pinned */
 
+	/**
+	 * pinned_contexts_list: List of pinned contexts. This list is only
+	 * assumed to be manipulated during driver load- or unload time and
+	 * does therefore not have any additional protection.
+	 */
+	struct list_head pinned_contexts_list;
+
 	intel_engine_mask_t saturated; /* submitting semaphores too late? */
 
 	struct {
-- 
2.31.1