drm/i915: Print how many objects are shared in per-process stats

The point of this measure is to gauge why a process has a lot of gem
objects in uses and why. Especially for compositors it's interesting
to know whether it's a leak of private objects or just a lot of use
from buffers shared with clients.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
[danvet: Add a bit of commit message flesh to address Ben's comment.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/i915_debugfs.c

@@ -301,7 +301,9 @@ static int i915_gem_stolen_list_info(struct seq_file *m, void *data)
 struct file_stats {
 	struct drm_i915_file_private *file_priv;
 	int count;
-	size_t total, global, active, inactive, unbound;
+	size_t total, unbound;
+	size_t global, shared;
+	size_t active, inactive;
 };
 
 static int per_file_stats(int id, void *ptr, void *data)
@@ -313,6 +315,9 @@ static int per_file_stats(int id, void *ptr, void *data)
 	stats->count++;
 	stats->total += obj->base.size;
 
+	if (obj->base.name || obj->base.dma_buf)
+		stats->shared += obj->base.size;
+
 	if (USES_FULL_PPGTT(obj->base.dev)) {
 		list_for_each_entry(vma, &obj->vma_list, vma_link) {
 			struct i915_hw_ppgtt *ppgtt;
@@ -450,13 +455,14 @@ static int i915_gem_object_info(struct seq_file *m, void* data)
 		 */
 		rcu_read_lock();
 		task = pid_task(file->pid, PIDTYPE_PID);
-		seq_printf(m, "%s: %u objects, %zu bytes (%zu active, %zu inactive, %zu global, %zu unbound)\n",
+		seq_printf(m, "%s: %u objects, %zu bytes (%zu active, %zu inactive, %zu global, %zu shared, %zu unbound)\n",
 			   task ? task->comm : "<unknown>",
 			   stats.count,
 			   stats.total,
 			   stats.active,
 			   stats.inactive,
 			   stats.global,
+			   stats.shared,
 			   stats.unbound);
 		rcu_read_unlock();
 	}