drm/vc4: Add a debugfs node for looking at BO allocation stats.

Signed-off-by: Eric Anholt <eric@anholt.net>

3 files changed, 68 insertions, 11 deletions

diff --git a/drivers/gpu/drm/vc4/vc4_bo.c b/drivers/gpu/drm/vc4/vc4_bo.c
index aa063eb4889f..ba91b7c17ab1 100644
--- a/drivers/gpu/drm/vc4/vc4_bo.c
+++ b/drivers/gpu/drm/vc4/vc4_bo.c
@@ -18,12 +18,37 @@
 #include "vc4_drv.h"
 #include "uapi/drm/vc4_drm.h"
 
+static struct {
+	u32 num_allocated;
+	u32 size_allocated;
+	u32 num_cached;
+	u32 size_cached;
+} bo_stats;
+
 static uint32_t
 bo_page_index(size_t size)
 {
 	return (size / PAGE_SIZE) - 1;
 }
 
+static void
+vc4_bo_destroy(struct vc4_bo *bo)
+{
+	bo_stats.num_allocated--;
+	bo_stats.size_allocated -= bo->base.base.size;
+	drm_gem_cma_free_object(&bo->base.base);
+}
+
+static void
+vc4_bo_remove_from_cache(struct vc4_bo *bo)
+{
+	bo_stats.num_cached--;
+	bo_stats.size_cached -= bo->base.base.size;
+
+	list_del(&bo->unref_head);
+	list_del(&bo->size_head);
+}
+
 static struct list_head *
 vc4_get_cache_list_for_size(struct drm_device *dev, size_t size)
 {
@@ -71,9 +96,8 @@ vc4_bo_cache_purge(struct drm_device *dev)
 	while (!list_empty(&vc4->bo_cache.time_list)) {
 		struct vc4_bo *bo = list_last_entry(&vc4->bo_cache.time_list,
 						    struct vc4_bo, unref_head);
-		list_del(&bo->unref_head);
-		list_del(&bo->size_head);
-		drm_gem_cma_free_object(&bo->base.base);
+		vc4_bo_remove_from_cache(bo);
+		vc4_bo_destroy(bo);
 	}
 }
 
@@ -90,8 +114,7 @@ vc4_bo_create(struct drm_device *dev, size_t size)
 		if (!list_empty(&vc4->bo_cache.size_list[page_index])) {
 			bo = list_first_entry(&vc4->bo_cache.size_list[page_index],
 					      struct vc4_bo, size_head);
-			list_del(&bo->size_head);
-			list_del(&bo->unref_head);
+			vc4_bo_remove_from_cache(bo);
 		}
 	}
 	if (bo) {
@@ -111,6 +134,9 @@ vc4_bo_create(struct drm_device *dev, size_t size)
 			return NULL;
 	}
 
+	bo_stats.num_allocated++;
+	bo_stats.size_allocated += size;
+
 	return to_vc4_bo(&cma_obj->base);
 }
 
@@ -157,9 +183,8 @@ vc4_bo_cache_free_old(struct drm_device *dev)
 			return;
 		}
 
-		list_del(&bo->unref_head);
-		list_del(&bo->size_head);
-		drm_gem_cma_free_object(&bo->base.base);
+		vc4_bo_remove_from_cache(bo);
+		vc4_bo_destroy(bo);
 	}
 }
 
@@ -179,19 +204,19 @@ vc4_free_object(struct drm_gem_object *gem_bo)
 	/* If the object references someone else's memory, we can't cache it.
 	 */
 	if (gem_bo->import_attach) {
-		drm_gem_cma_free_object(gem_bo);
+		vc4_bo_destroy(bo);
 		return;
 	}
 
 	/* Don't cache if it was publicly named. */
 	if (gem_bo->name) {
-		drm_gem_cma_free_object(gem_bo);
+		vc4_bo_destroy(bo);
 		return;
 	}
 
 	cache_list = vc4_get_cache_list_for_size(dev, gem_bo->size);
 	if (!cache_list) {
-		drm_gem_cma_free_object(gem_bo);
+		vc4_bo_destroy(bo);
 		return;
 	}
 
@@ -208,6 +233,9 @@ vc4_free_object(struct drm_gem_object *gem_bo)
 	list_add(&bo->size_head, cache_list);
 	list_add(&bo->unref_head, &vc4->bo_cache.time_list);
 
+	bo_stats.num_cached++;
+	bo_stats.size_cached += gem_bo->size;
+
 	vc4_bo_cache_free_old(dev);
 }
 
@@ -318,3 +346,30 @@ vc4_mmap_bo_ioctl(struct drm_device *dev, void *data,
 	drm_gem_object_unreference(gem_obj);
 	return 0;
 }
+
+#ifdef CONFIG_DEBUG_FS
+int vc4_bo_stats_debugfs(struct seq_file *m, void *unused)
+{
+	struct drm_info_node *node = (struct drm_info_node *) m->private;
+	struct drm_device *dev = node->minor->dev;
+
+	mutex_lock(&dev->struct_mutex);
+
+	seq_printf(m, "num bos allocated: %d\n",
+		   bo_stats.num_allocated);
+	seq_printf(m, "size bos allocated: %dkb\n",
+		   bo_stats.size_allocated / 1024);
+	seq_printf(m, "num bos used: %d\n",
+		   bo_stats.num_allocated - bo_stats.num_cached);
+	seq_printf(m, "size bos used: %dkb\n",
+		   (bo_stats.size_allocated - bo_stats.size_cached) / 1024);
+	seq_printf(m, "num bos cached: %d\n",
+		   bo_stats.num_cached);
+	seq_printf(m, "size bos cached: %dkb\n",
+		   bo_stats.size_cached / 1024);
+
+	mutex_unlock(&dev->struct_mutex);
+
+	return 0;
+}
+#endif
diff --git a/drivers/gpu/drm/vc4/vc4_debugfs.c b/drivers/gpu/drm/vc4/vc4_debugfs.c
index abd541f470ca..ca4743126736 100644
--- a/drivers/gpu/drm/vc4/vc4_debugfs.c
+++ b/drivers/gpu/drm/vc4/vc4_debugfs.c
@@ -16,6 +16,7 @@
 #include "vc4_regs.h"
 
 static const struct drm_info_list vc4_debugfs_list[] = {
+	{"bo_stats", vc4_bo_stats_debugfs, 0},
 	{"v3d_ident", vc4_v3d_debugfs_ident, 0},
 	{"v3d_regs", vc4_v3d_debugfs_regs, 0},
 	{"hdmi_regs", vc4_hdmi_debugfs_regs, 0},
diff --git a/drivers/gpu/drm/vc4/vc4_drv.h b/drivers/gpu/drm/vc4/vc4_drv.h
index aa6592dd1fc9..fa14c801b1a4 100644
--- a/drivers/gpu/drm/vc4/vc4_drv.h
+++ b/drivers/gpu/drm/vc4/vc4_drv.h
@@ -366,6 +366,7 @@ int vc4_create_bo_ioctl(struct drm_device *dev, void *data,
 			struct drm_file *file_priv);
 int vc4_mmap_bo_ioctl(struct drm_device *dev, void *data,
 		      struct drm_file *file_priv);
+int vc4_bo_stats_debugfs(struct seq_file *m, void *unused);
 
 /* vc4_debugfs.c */
 int vc4_debugfs_init(struct drm_minor *minor);