Merge branch 'ref_tracker-add-ability-to-register-a-debugfs-file-for-a-ref_tracker_dir'

Jeff Layton says:

====================
ref_tracker: add ability to register a debugfs file for a ref_tracker_dir

For those just joining in, this series adds a new top-level
"ref_tracker" debugfs directory, and has each ref_tracker_dir register a
file in there as part of its initialization. It also adds the ability to
register a symlink with a more human-usable name that points to the
file, and does some general cleanup of how the ref_tracker object names
are handled.

v14: https://lore.kernel.org/[email protected]
v13: https://lore.kernel.org/[email protected]
v12: https://lore.kernel.org/[email protected]
v11: https://lore.kernel.org/[email protected]
v10: https://lore.kernel.org/[email protected]
v9: https://lore.kernel.org/[email protected]
v8: https://lore.kernel.org/[email protected]
v7: https://lore.kernel.org/[email protected]
v6: https://lore.kernel.org/[email protected]
v5: https://lore.kernel.org/[email protected]
v4: https://lore.kernel.org/[email protected]
v3: https://lore.kernel.org/[email protected]
v2: https://lore.kernel.org/[email protected]
v1: https://lore.kernel.org/[email protected]
====================

Link: https://patch.msgid.link/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>

Author: kuba-moo

drivers/gpu/drm/display/drm_dp_tunnel.c

@@ -1920,7 +1920,7 @@ drm_dp_tunnel_mgr_create(struct drm_device *dev, int max_group_count)
 	}
 
 #ifdef CONFIG_DRM_DISPLAY_DP_TUNNEL_STATE_DEBUG
-	ref_tracker_dir_init(&mgr->ref_tracker, 16, "dptun");
+	ref_tracker_dir_init(&mgr->ref_tracker, 16, "drm_dptun");
 #endif
 
 	for (i = 0; i < max_group_count; i++) {

drivers/gpu/drm/i915/intel_runtime_pm.c

@@ -59,7 +59,9 @@ static struct drm_i915_private *rpm_to_i915(struct intel_runtime_pm *rpm)
 
 static void init_intel_runtime_pm_wakeref(struct intel_runtime_pm *rpm)
 {
-	ref_tracker_dir_init(&rpm->debug, INTEL_REFTRACK_DEAD_COUNT, dev_name(rpm->kdev));
+	if (!rpm->debug.class)
+		ref_tracker_dir_init(&rpm->debug, INTEL_REFTRACK_DEAD_COUNT,
+				     "intel_runtime_pm");
 }
 
 static intel_wakeref_t

drivers/gpu/drm/i915/intel_wakeref.c

@@ -114,7 +114,8 @@ void __intel_wakeref_init(struct intel_wakeref *wf,
 			 "wakeref.work", &key->work, 0);
 
 #if IS_ENABLED(CONFIG_DRM_I915_DEBUG_WAKEREF)
-	ref_tracker_dir_init(&wf->debug, INTEL_REFTRACK_DEAD_COUNT, name);
+	if (!wf->debug.class)
+		ref_tracker_dir_init(&wf->debug, INTEL_REFTRACK_DEAD_COUNT, "intel_wakeref");
 #endif
 }
 

include/linux/ref_tracker.h

@@ -6,6 +6,8 @@
 #include <linux/spinlock.h>
 #include <linux/stackdepot.h>
 
+#define __ostream_printf __printf(2, 3)
+
 struct ref_tracker;
 
 struct ref_tracker_dir {
@@ -17,15 +19,45 @@ struct ref_tracker_dir {
 	bool			dead;
 	struct list_head	list; /* List of active trackers */
 	struct list_head	quarantine; /* List of dead trackers */
-	char			name[32];
+	const char		*class; /* object classname */
 #endif
 };
 
 #ifdef CONFIG_REF_TRACKER
 
+#ifdef CONFIG_DEBUG_FS
+
+void ref_tracker_dir_debugfs(struct ref_tracker_dir *dir);
+void ref_tracker_dir_symlink(struct ref_tracker_dir *dir, const char *fmt, ...);
+
+#else /* CONFIG_DEBUG_FS */
+
+static inline void ref_tracker_dir_debugfs(struct ref_tracker_dir *dir)
+{
+}
+
+static inline __ostream_printf
+void ref_tracker_dir_symlink(struct ref_tracker_dir *dir, const char *fmt, ...)
+{
+}
+
+#endif /* CONFIG_DEBUG_FS */
+
+/**
+ * ref_tracker_dir_init - initialize a ref_tracker dir
+ * @dir: ref_tracker_dir to be initialized
+ * @quarantine_count: max number of entries to be tracked
+ * @class: pointer to static string that describes object type
+ *
+ * Initialize a ref_tracker_dir. If debugfs is configured, then a file
+ * will also be created for it under the top-level ref_tracker debugfs
+ * directory.
+ *
+ * Note that @class must point to a static string.
+ */
 static inline void ref_tracker_dir_init(struct ref_tracker_dir *dir,
 					unsigned int quarantine_count,
-					const char *name)
+					const char *class)
 {
 	INIT_LIST_HEAD(&dir->list);
 	INIT_LIST_HEAD(&dir->quarantine);
@@ -34,7 +66,8 @@ static inline void ref_tracker_dir_init(struct ref_tracker_dir *dir,
 	dir->dead = false;
 	refcount_set(&dir->untracked, 1);
 	refcount_set(&dir->no_tracker, 1);
-	strscpy(dir->name, name, sizeof(dir->name));
+	dir->class = class;
+	ref_tracker_dir_debugfs(dir);
 	stack_depot_init();
 }
 
@@ -58,7 +91,16 @@ int ref_tracker_free(struct ref_tracker_dir *dir,
 
 static inline void ref_tracker_dir_init(struct ref_tracker_dir *dir,
 					unsigned int quarantine_count,
-					const char *name)
+					const char *class)
+{
+}
+
+static inline void ref_tracker_dir_debugfs(struct ref_tracker_dir *dir)
+{
+}
+
+static inline __ostream_printf
+void ref_tracker_dir_symlink(struct ref_tracker_dir *dir, const char *fmt, ...)
 {
 }