devres: Enable trace events

In some cases the printf() mechanism is too heavy and can't be used.
For example, when debugging a race condition involving devres API.
When CONFIG_DEBUG_DEVRES is enabled I can't reproduce an issue, and
otherwise it's quite visible with a useful information being collected.

Enable trace events for devres part of the driver core.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20210517122946.53161-4-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 20 insertions, 27 deletions

diff --git a/drivers/base/devres.c b/drivers/base/devres.c
index dee48858663f..eaa9a5cd1db9 100644
--- a/drivers/base/devres.c
+++ b/drivers/base/devres.c
@@ -14,14 +14,13 @@
 #include <asm/sections.h>
 
 #include "base.h"
+#include "trace.h"
 
 struct devres_node {
 	struct list_head		entry;
 	dr_release_t			release;
-#ifdef CONFIG_DEBUG_DEVRES
 	const char			*name;
 	size_t				size;
-#endif
 };
 
 struct devres {
@@ -43,10 +42,6 @@ struct devres_group {
 	/* -- 8 pointers */
 };
 
-#ifdef CONFIG_DEBUG_DEVRES
-static int log_devres = 0;
-module_param_named(log, log_devres, int, S_IRUGO | S_IWUSR);
-
 static void set_node_dbginfo(struct devres_node *node, const char *name,
 			     size_t size)
 {
@@ -54,7 +49,11 @@ static void set_node_dbginfo(struct devres_node *node, const char *name,
 	node->size = size;
 }
 
-static void devres_log(struct device *dev, struct devres_node *node,
+#ifdef CONFIG_DEBUG_DEVRES
+static int log_devres = 0;
+module_param_named(log, log_devres, int, S_IRUGO | S_IWUSR);
+
+static void devres_dbg(struct device *dev, struct devres_node *node,
 		       const char *op)
 {
 	if (unlikely(log_devres))
@@ -62,10 +61,16 @@ static void devres_log(struct device *dev, struct devres_node *node,
 			op, node, node->name, node->size);
 }
 #else /* CONFIG_DEBUG_DEVRES */
-#define set_node_dbginfo(node, n, s)	do {} while (0)
-#define devres_log(dev, node, op)	do {} while (0)
+#define devres_dbg(dev, node, op)	do {} while (0)
 #endif /* CONFIG_DEBUG_DEVRES */
 
+static void devres_log(struct device *dev, struct devres_node *node,
+		       const char *op)
+{
+	trace_devres_log(dev, op, node, node->name, node->size);
+	devres_dbg(dev, node, op);
+}
+
 /*
  * Release functions for devres group.  These callbacks are used only
  * for identification.
@@ -134,26 +139,13 @@ static void replace_dr(struct device *dev,
 	list_replace(&old->entry, &new->entry);
 }
 
-#ifdef CONFIG_DEBUG_DEVRES
-void * __devres_alloc_node(dr_release_t release, size_t size, gfp_t gfp, int nid,
-		      const char *name)
-{
-	struct devres *dr;
-
-	dr = alloc_dr(release, size, gfp | __GFP_ZERO, nid);
-	if (unlikely(!dr))
-		return NULL;
-	set_node_dbginfo(&dr->node, name, size);
-	return dr->data;
-}
-EXPORT_SYMBOL_GPL(__devres_alloc_node);
-#else
 /**
- * devres_alloc_node - Allocate device resource data
+ * __devres_alloc_node - Allocate device resource data
  * @release: Release function devres will be associated with
  * @size: Allocation size
  * @gfp: Allocation flags
  * @nid: NUMA node
+ * @name: Name of the resource
  *
  * Allocate devres of @size bytes.  The allocated area is zeroed, then
  * associated with @release.  The returned pointer can be passed to
@@ -162,17 +154,18 @@ EXPORT_SYMBOL_GPL(__devres_alloc_node);
  * RETURNS:
  * Pointer to allocated devres on success, NULL on failure.
  */
-void * devres_alloc_node(dr_release_t release, size_t size, gfp_t gfp, int nid)
+void *__devres_alloc_node(dr_release_t release, size_t size, gfp_t gfp, int nid,
+			  const char *name)
 {
 	struct devres *dr;
 
 	dr = alloc_dr(release, size, gfp | __GFP_ZERO, nid);
 	if (unlikely(!dr))
 		return NULL;
+	set_node_dbginfo(&dr->node, name, size);
 	return dr->data;
 }
-EXPORT_SYMBOL_GPL(devres_alloc_node);
-#endif
+EXPORT_SYMBOL_GPL(__devres_alloc_node);
 
 /**
  * devres_for_each_res - Resource iterator