drm/i915/gt: Show all active timelines for debugging

Include the active timelines for debugfs/i915_engine_info, so that we
can see which have unready requests inflight which are not shown
otherwise.

Suggested-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20201119165616.10834-4-chris@chris-wilson.co.uk

diff --git a/drivers/gpu/drm/i915/gt/intel_timeline.c b/drivers/gpu/drm/i915/gt/intel_timeline.c
index 7ea94d2..512afac 100644 (file)
--- a/drivers/gpu/drm/i915/gt/intel_timeline.c
+++ b/drivers/gpu/drm/i915/gt/intel_timeline.c
@@ -617,6 +617,86 @@ void intel_gt_fini_timelines(struct intel_gt *gt)
        GEM_BUG_ON(!list_empty(&timelines->hwsp_free_list));
 }
 
+void intel_gt_show_timelines(struct intel_gt *gt,
+                            struct drm_printer *m,
+                            void (*show_request)(struct drm_printer *m,
+                                                 const struct i915_request *rq,
+                                                 const char *prefix,
+                                                 int indent))
+{
+       struct intel_gt_timelines *timelines = &gt->timelines;
+       struct intel_timeline *tl, *tn;
+       LIST_HEAD(free);
+
+       spin_lock(&timelines->lock);
+       list_for_each_entry_safe(tl, tn, &timelines->active_list, link) {
+               unsigned long count, ready, inflight;
+               struct i915_request *rq, *rn;
+               struct dma_fence *fence;
+
+               if (!mutex_trylock(&tl->mutex)) {
+                       drm_printf(m, "Timeline %llx: busy; skipping\n",
+                                  tl->fence_context);
+                       continue;
+               }
+
+               intel_timeline_get(tl);
+               GEM_BUG_ON(!atomic_read(&tl->active_count));
+               atomic_inc(&tl->active_count); /* pin the list element */
+               spin_unlock(&timelines->lock);
+
+               count = 0;
+               ready = 0;
+               inflight = 0;
+               list_for_each_entry_safe(rq, rn, &tl->requests, link) {
+                       if (i915_request_completed(rq))
+                               continue;
+
+                       count++;
+                       if (i915_request_is_ready(rq))
+                               ready++;
+                       if (i915_request_is_active(rq))
+                               inflight++;
+               }
+
+               drm_printf(m, "Timeline %llx: { ", tl->fence_context);
+               drm_printf(m, "count: %lu, ready: %lu, inflight: %lu",
+                          count, ready, inflight);
+               drm_printf(m, ", seqno: { current: %d, last: %d }",
+                          *tl->hwsp_seqno, tl->seqno);
+               fence = i915_active_fence_get(&tl->last_request);
+               if (fence) {
+                       drm_printf(m, ", engine: %s",
+                                  to_request(fence)->engine->name);
+                       dma_fence_put(fence);
+               }
+               drm_printf(m, " }\n");
+
+               if (show_request) {
+                       list_for_each_entry_safe(rq, rn, &tl->requests, link)
+                               show_request(m, rq, "", 2);
+               }
+
+               mutex_unlock(&tl->mutex);
+               spin_lock(&timelines->lock);
+
+               /* Resume list iteration after reacquiring spinlock */
+               list_safe_reset_next(tl, tn, link);
+               if (atomic_dec_and_test(&tl->active_count))
+                       list_del(&tl->link);
+
+               /* Defer the final release to after the spinlock */
+               if (refcount_dec_and_test(&tl->kref.refcount)) {
+                       GEM_BUG_ON(atomic_read(&tl->active_count));
+                       list_add(&tl->link, &free);
+               }
+       }
+       spin_unlock(&timelines->lock);
+
+       list_for_each_entry_safe(tl, tn, &free, link)
+               __intel_timeline_free(&tl->kref);
+}
+
 #if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
 #include "gt/selftests/mock_timeline.c"
 #include "gt/selftest_timeline.c"

diff --git a/drivers/gpu/drm/i915/gt/intel_timeline.h b/drivers/gpu/drm/i915/gt/intel_timeline.h
index 9882cd9..634aceb 100644 (file)
--- a/drivers/gpu/drm/i915/gt/intel_timeline.h
+++ b/drivers/gpu/drm/i915/gt/intel_timeline.h
@@ -31,6 +31,8 @@
 #include "i915_syncmap.h"
 #include "intel_timeline_types.h"
 
+struct drm_printer;
+
 struct intel_timeline *
 __intel_timeline_create(struct intel_gt *gt,
                        struct i915_vma *global_hwsp,
@@ -106,4 +108,11 @@ int intel_timeline_read_hwsp(struct i915_request *from,
 void intel_gt_init_timelines(struct intel_gt *gt);
 void intel_gt_fini_timelines(struct intel_gt *gt);
 
+void intel_gt_show_timelines(struct intel_gt *gt,
+                            struct drm_printer *m,
+                            void (*show_request)(struct drm_printer *m,
+                                                 const struct i915_request *rq,
+                                                 const char *prefix,
+                                                 int indent));
+
 #endif

diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
index 77e76b6..354b95c 100644 (file)
--- a/drivers/gpu/drm/i915/i915_debugfs.c
+++ b/drivers/gpu/drm/i915/i915_debugfs.c
@@ -1306,24 +1306,26 @@ static int i915_runtime_pm_status(struct seq_file *m, void *unused)
 
 static int i915_engine_info(struct seq_file *m, void *unused)
 {
-       struct drm_i915_private *dev_priv = node_to_i915(m->private);
+       struct drm_i915_private *i915 = node_to_i915(m->private);
        struct intel_engine_cs *engine;
        intel_wakeref_t wakeref;
        struct drm_printer p;
 
-       wakeref = intel_runtime_pm_get(&dev_priv->runtime_pm);
+       wakeref = intel_runtime_pm_get(&i915->runtime_pm);
 
        seq_printf(m, "GT awake? %s [%d]\n",
-                  yesno(dev_priv->gt.awake),
-                  atomic_read(&dev_priv->gt.wakeref.count));
+                  yesno(i915->gt.awake),
+                  atomic_read(&i915->gt.wakeref.count));
        seq_printf(m, "CS timestamp frequency: %u Hz\n",
-                  RUNTIME_INFO(dev_priv)->cs_timestamp_frequency_hz);
+                  RUNTIME_INFO(i915)->cs_timestamp_frequency_hz);
 
        p = drm_seq_file_printer(m);
-       for_each_uabi_engine(engine, dev_priv)
+       for_each_uabi_engine(engine, i915)
                intel_engine_dump(engine, &p, "%s\n", engine->name);
 
-       intel_runtime_pm_put(&dev_priv->runtime_pm, wakeref);
+       intel_gt_show_timelines(&i915->gt, &p, NULL);
+
+       intel_runtime_pm_put(&i915->runtime_pm, wakeref);
 
        return 0;
 }