diff --git a/drivers/gpu/drm/i915/gt/intel_engine_cs.c b/drivers/gpu/drm/i915/gt/intel_engine_cs.c
index b9613d044393fac2468fb75d31d976842461eea1..8f6e353caa667ee2fee4554db4e6a232e071f9c1 100644
--- a/drivers/gpu/drm/i915/gt/intel_engine_cs.c
+++ b/drivers/gpu/drm/i915/gt/intel_engine_cs.c
@@ -28,13 +28,13 @@
#include "i915_drv.h"
-#include "gt/intel_gt.h"
-
+#include "intel_context.h"
#include "intel_engine.h"
#include "intel_engine_pm.h"
#include "intel_engine_pool.h"
#include "intel_engine_user.h"
-#include "intel_context.h"
+#include "intel_gt.h"
+#include "intel_gt_requests.h"
#include "intel_lrc.h"
#include "intel_reset.h"
#include "intel_ring.h"
@@ -617,6 +617,7 @@ static int intel_engine_setup_common(struct intel_engine_cs *engine)
intel_engine_init_execlists(engine);
intel_engine_init_cmd_parser(engine);
intel_engine_init__pm(engine);
+ intel_engine_init_retire(engine);
intel_engine_pool_init(&engine->pool);
@@ -839,6 +840,7 @@ void intel_engine_cleanup_common(struct intel_engine_cs *engine)
cleanup_status_page(engine);
+ intel_engine_fini_retire(engine);
intel_engine_pool_fini(&engine->pool);
intel_engine_fini_breadcrumbs(engine);
intel_engine_cleanup_cmd_parser(engine);
diff --git a/drivers/gpu/drm/i915/gt/intel_engine_types.h b/drivers/gpu/drm/i915/gt/intel_engine_types.h
index 758f0e8ec6723dd8f0a89d987e9e0eb248f4e259..17f1f1441efc9dba383e51959aa936a4177b8bfa 100644
--- a/drivers/gpu/drm/i915/gt/intel_engine_types.h
+++ b/drivers/gpu/drm/i915/gt/intel_engine_types.h
@@ -451,6 +451,14 @@ struct intel_engine_cs {
struct intel_engine_execlists execlists;
+ /*
+ * Keep track of completed timelines on this engine for early
+ * retirement with the goal of quickly enabling powersaving as
+ * soon as the engine is idle.
+ */
+ struct intel_timeline *retire;
+ struct work_struct retire_work;
+
/* status_notifier: list of callbacks for context-switch changes */
struct atomic_notifier_head context_status_notifier;
diff --git a/drivers/gpu/drm/i915/gt/intel_gt_requests.c b/drivers/gpu/drm/i915/gt/intel_gt_requests.c
index f02f781b84924777d079dbcf03c0b1ff39ff93ad..8cb5421e5f0ec30c69867272195157bca97df66e 100644
--- a/drivers/gpu/drm/i915/gt/intel_gt_requests.c
+++ b/drivers/gpu/drm/i915/gt/intel_gt_requests.c
@@ -4,6 +4,8 @@
* Copyright © 2019 Intel Corporation
*/
+#include <linux/workqueue.h>
+
#include "i915_drv.h" /* for_each_engine() */
#include "i915_request.h"
#include "intel_gt.h"
@@ -29,6 +31,79 @@ static void flush_submission(struct intel_gt *gt)
intel_engine_flush_submission(engine);
}
+static void engine_retire(struct work_struct *work)
+{
+ struct intel_engine_cs *engine =
+ container_of(work, typeof(*engine), retire_work);
+ struct intel_timeline *tl = xchg(&engine->retire, NULL);
+
+ do {
+ struct intel_timeline *next = xchg(&tl->retire, NULL);
+
+ /*
+ * Our goal here is to retire _idle_ timelines as soon as
+ * possible (as they are idle, we do not expect userspace
+ * to be cleaning up anytime soon).
+ *
+ * If the timeline is currently locked, either it is being
+ * retired elsewhere or about to be!
+ */
+ if (mutex_trylock(&tl->mutex)) {
+ retire_requests(tl);
+ mutex_unlock(&tl->mutex);
+ }
+ intel_timeline_put(tl);
+
+ GEM_BUG_ON(!next);
+ tl = ptr_mask_bits(next, 1);
+ } while (tl);
+}
+
+static bool add_retire(struct intel_engine_cs *engine,
+ struct intel_timeline *tl)
+{
+ struct intel_timeline *first;
+
+ /*
+ * We open-code a llist here to include the additional tag [BIT(0)]
+ * so that we know when the timeline is already on a
+ * retirement queue: either this engine or another.
+ *
+ * However, we rely on that a timeline can only be active on a single
+ * engine at any one time and that add_retire() is called before the
+ * engine releases the timeline and transferred to another to retire.
+ */
+
+ if (READ_ONCE(tl->retire)) /* already queued */
+ return false;
+
+ intel_timeline_get(tl);
+ first = READ_ONCE(engine->retire);
+ do
+ tl->retire = ptr_pack_bits(first, 1, 1);
+ while (!try_cmpxchg(&engine->retire, &first, tl));
+
+ return !first;
+}
+
+void intel_engine_add_retire(struct intel_engine_cs *engine,
+ struct intel_timeline *tl)
+{
+ if (add_retire(engine, tl))
+ schedule_work(&engine->retire_work);
+}
+
+void intel_engine_init_retire(struct intel_engine_cs *engine)
+{
+ INIT_WORK(&engine->retire_work, engine_retire);
+}
+
+void intel_engine_fini_retire(struct intel_engine_cs *engine)
+{
+ flush_work(&engine->retire_work);
+ GEM_BUG_ON(engine->retire);
+}
+
long intel_gt_retire_requests_timeout(struct intel_gt *gt, long timeout)
{
struct intel_gt_timelines *timelines = >->timelines;
diff --git a/drivers/gpu/drm/i915/gt/intel_gt_requests.h b/drivers/gpu/drm/i915/gt/intel_gt_requests.h
index fde546424c63a8f4fc0b2e564d6538ea9f21b4ce..dbac53baf1cb83c519502f9440a3d88c901e3376 100644
--- a/drivers/gpu/drm/i915/gt/intel_gt_requests.h
+++ b/drivers/gpu/drm/i915/gt/intel_gt_requests.h
@@ -7,7 +7,9 @@
#ifndef INTEL_GT_REQUESTS_H
#define INTEL_GT_REQUESTS_H
+struct intel_engine_cs;
struct intel_gt;
+struct intel_timeline;
long intel_gt_retire_requests_timeout(struct intel_gt *gt, long timeout);
static inline void intel_gt_retire_requests(struct intel_gt *gt)
@@ -15,6 +17,11 @@ static inline void intel_gt_retire_requests(struct intel_gt *gt)
intel_gt_retire_requests_timeout(gt, 0);
}
+void intel_engine_init_retire(struct intel_engine_cs *engine);
+void intel_engine_add_retire(struct intel_engine_cs *engine,
+ struct intel_timeline *tl);
+void intel_engine_fini_retire(struct intel_engine_cs *engine);
+
int intel_gt_wait_for_idle(struct intel_gt *gt, long timeout);
void intel_gt_init_requests(struct intel_gt *gt);
diff --git a/drivers/gpu/drm/i915/gt/intel_lrc.c b/drivers/gpu/drm/i915/gt/intel_lrc.c
index 6090357a00fa1f721eb7b1fe815e6015cc34844e..4cd0d46b5da65cbe65a272457d5103ad412a459d 100644
--- a/drivers/gpu/drm/i915/gt/intel_lrc.c
+++ b/drivers/gpu/drm/i915/gt/intel_lrc.c
@@ -142,6 +142,7 @@
#include "intel_engine_pm.h"
#include "intel_gt.h"
#include "intel_gt_pm.h"
+#include "intel_gt_requests.h"
#include "intel_lrc_reg.h"
#include "intel_mocs.h"
#include "intel_reset.h"
@@ -1170,6 +1171,14 @@ __execlists_schedule_out(struct i915_request *rq,
* refrain from doing non-trivial work here.
*/
+ /*
+ * If we have just completed this context, the engine may now be
+ * idle and we want to re-enter powersaving.
+ */
+ if (list_is_last(&rq->link, &ce->timeline->requests) &&
+ i915_request_completed(rq))
+ intel_engine_add_retire(engine, ce->timeline);
+
intel_engine_context_out(engine);
execlists_context_status_change(rq, INTEL_CONTEXT_SCHEDULE_OUT);
intel_gt_pm_put_async(engine->gt);
diff --git a/drivers/gpu/drm/i915/gt/intel_timeline.c b/drivers/gpu/drm/i915/gt/intel_timeline.c
index b190a5d9ab02e8d2b76c109bdee377653cc3043e..c1d2419444f8edcb46f8cd6053783821812a8355 100644
--- a/drivers/gpu/drm/i915/gt/intel_timeline.c
+++ b/drivers/gpu/drm/i915/gt/intel_timeline.c
@@ -277,6 +277,7 @@ void intel_timeline_fini(struct intel_timeline *timeline)
{
GEM_BUG_ON(atomic_read(&timeline->pin_count));
GEM_BUG_ON(!list_empty(&timeline->requests));
+ GEM_BUG_ON(timeline->retire);
if (timeline->hwsp_cacheline)
cacheline_free(timeline->hwsp_cacheline);
diff --git a/drivers/gpu/drm/i915/gt/intel_timeline_types.h b/drivers/gpu/drm/i915/gt/intel_timeline_types.h
index 5244615ed1cb4a13b5a81737bcd67e75e7472b09..aaf15cbe1ce18526c6f8794957785b758d33a149 100644
--- a/drivers/gpu/drm/i915/gt/intel_timeline_types.h
+++ b/drivers/gpu/drm/i915/gt/intel_timeline_types.h
@@ -66,6 +66,9 @@ struct intel_timeline {
*/
struct i915_active_fence last_request;
+ /** A chain of completed timelines ready for early retirement. */
+ struct intel_timeline *retire;
+
/**
* We track the most recent seqno that we wait on in every context so
* that we only have to emit a new await and dependency on a more