1 files changed, 137 insertions, 0 deletions
diff --git a/include/linux/dynamic_debug.h b/include/linux/dynamic_debug.h
new file mode 100644
index 000000000..4f1bbc68c
--- /dev/null
+++ b/include/linux/dynamic_debug.h
@@ -0,0 +1,137 @@
+#ifndef _DYNAMIC_DEBUG_H
+#define _DYNAMIC_DEBUG_H
+
+/*
+ * An instance of this structure is created in a special
+ * ELF section at every dynamic debug callsite.  At runtime,
+ * the special section is treated as an array of these.
+ */
+struct _ddebug {
+	/*
+	 * These fields are used to drive the user interface
+	 * for selecting and displaying debug callsites.
+	 */
+	const char *modname;
+	const char *function;
+	const char *filename;
+	const char *format;
+	unsigned int lineno:18;
+	/*
+	 * The flags field controls the behaviour at the callsite.
+	 * The bits here are changed dynamically when the user
+	 * writes commands to <debugfs>/dynamic_debug/control
+	 */
+#define _DPRINTK_FLAGS_NONE	0
+#define _DPRINTK_FLAGS_PRINT	(1<<0) /* printk() a message using the format */
+#define _DPRINTK_FLAGS_INCL_MODNAME	(1<<1)
+#define _DPRINTK_FLAGS_INCL_FUNCNAME	(1<<2)
+#define _DPRINTK_FLAGS_INCL_LINENO	(1<<3)
+#define _DPRINTK_FLAGS_INCL_TID		(1<<4)
+#if defined DEBUG
+#define _DPRINTK_FLAGS_DEFAULT _DPRINTK_FLAGS_PRINT
+#else
+#define _DPRINTK_FLAGS_DEFAULT 0
+#endif
+	unsigned int flags:8;
+} __attribute__((aligned(8)));
+
+
+int ddebug_add_module(struct _ddebug *tab, unsigned int n,
+				const char *modname);
+
+#if defined(CONFIG_DYNAMIC_DEBUG)
+extern int ddebug_remove_module(const char *mod_name);
+extern __printf(2, 3)
+void __dynamic_pr_debug(struct _ddebug *descriptor, const char *fmt, ...);
+
+extern int ddebug_dyndbg_module_param_cb(char *param, char *val,
+					const char *modname);
+
+struct device;
+
+extern __printf(3, 4)
+void __dynamic_dev_dbg(struct _ddebug *descriptor, const struct device *dev,
+		       const char *fmt, ...);
+
+struct net_device;
+
+extern __printf(3, 4)
+void __dynamic_netdev_dbg(struct _ddebug *descriptor,
+			  const struct net_device *dev,
+			  const char *fmt, ...);
+
+#define DEFINE_DYNAMIC_DEBUG_METADATA(name, fmt)		\
+	static struct _ddebug  __aligned(8)			\
+	__attribute__((section("__verbose"))) name = {		\
+		.modname = KBUILD_MODNAME,			\
+		.function = __func__,				\
+		.filename = __FILE__,				\
+		.format = (fmt),				\
+		.lineno = __LINE__,				\
+		.flags =  _DPRINTK_FLAGS_DEFAULT,		\
+	}
+
+#define dynamic_pr_debug(fmt, ...)				\
+do {								\
+	DEFINE_DYNAMIC_DEBUG_METADATA(descriptor, fmt);		\
+	if (unlikely(descriptor.flags & _DPRINTK_FLAGS_PRINT))	\
+		__dynamic_pr_debug(&descriptor, pr_fmt(fmt),	\
+				   ##__VA_ARGS__);		\
+} while (0)
+
+#define dynamic_dev_dbg(dev, fmt, ...)				\
+do {								\
+	DEFINE_DYNAMIC_DEBUG_METADATA(descriptor, fmt);		\
+	if (unlikely(descriptor.flags & _DPRINTK_FLAGS_PRINT))	\
+		__dynamic_dev_dbg(&descriptor, dev, fmt,	\
+				  ##__VA_ARGS__);		\
+} while (0)
+
+#define dynamic_netdev_dbg(dev, fmt, ...)			\
+do {								\
+	DEFINE_DYNAMIC_DEBUG_METADATA(descriptor, fmt);		\
+	if (unlikely(descriptor.flags & _DPRINTK_FLAGS_PRINT))	\
+		__dynamic_netdev_dbg(&descriptor, dev, fmt,	\
+				     ##__VA_ARGS__);		\
+} while (0)
+
+#define dynamic_hex_dump(prefix_str, prefix_type, rowsize,	\
+			 groupsize, buf, len, ascii)		\
+do {								\
+	DEFINE_DYNAMIC_DEBUG_METADATA(descriptor,		\
+		__builtin_constant_p(prefix_str) ? prefix_str : "hexdump");\
+	if (unlikely(descriptor.flags & _DPRINTK_FLAGS_PRINT))	\
+		print_hex_dump(KERN_DEBUG, prefix_str,		\
+			       prefix_type, rowsize, groupsize,	\
+			       buf, len, ascii);		\
+} while (0)
+
+#else
+
+#include <linux/string.h>
+#include <linux/errno.h>
+
+static inline int ddebug_remove_module(const char *mod)
+{
+	return 0;
+}
+
+static inline int ddebug_dyndbg_module_param_cb(char *param, char *val,
+						const char *modname)
+{
+	if (strstr(param, "dyndbg")) {
+		/* avoid pr_warn(), which wants pr_fmt() fully defined */
+		printk(KERN_WARNING "dyndbg param is supported only in "
+			"CONFIG_DYNAMIC_DEBUG builds\n");
+		return 0; /* allow and ignore */
+	}
+	return -EINVAL;
+}
+
+#define dynamic_pr_debug(fmt, ...)					\
+	do { if (0) printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__); } while (0)
+#define dynamic_dev_dbg(dev, fmt, ...)					\
+	do { if (0) dev_printk(KERN_DEBUG, dev, fmt, ##__VA_ARGS__); } while (0)
+#endif
+
+#endif