params: add 3rd arg to option handler callback signature

Add a 3rd arg, named "doing", to unknown-options callbacks invoked
from parse_args(). The arg is passed as:

  "Booting kernel" from start_kernel(),
  initcall_level_names[i] from do_initcall_level(),
  mod->name from load_module(), via parse_args(), parse_one()

parse_args() already has the "name" parameter, which is renamed to
"doing" to better reflect current uses 1,2 above.  parse_args() passes
it to an altered parse_one(), which now passes it down into the
unknown option handler callbacks.

The mod->name will be needed to handle dyndbg for loadable modules,
since params passed by modprobe are not qualified (they do not have a
"$modname." prefix), and by the time the unknown-param callback is
called, the module name is not otherwise available.

Minor tweaks:

Add param-name to parse_one's pr_debug(), current message doesnt
identify the param being handled, add it.

Add a pr_info to print current level and level_name of the initcall,
and number of registered initcalls at that level.  This adds 7 lines
to dmesg output, like:

   initlevel:6=device, 172 registered initcalls

Drop "parameters" from initcall_level_names[], its unhelpful in the
pr_info() added above.  This array is passed into parse_args() by
do_initcall_level().

CC: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Acked-by: Jason Baron <jbaron@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

include/linux/moduleparam.h

@@ -320,7 +320,8 @@ extern int parse_args(const char *name,
 		      unsigned num,
 		      s16 level_min,
 		      s16 level_max,
-		      int (*unknown)(char *param, char *val));
+		      int (*unknown)(char *param, char *val,
+			      const char *doing));
 
 /* Called by module remove. */
 #ifdef CONFIG_SYSFS

init/main.c

@@ -229,7 +229,8 @@ early_param("loglevel", loglevel);
  * Unknown boot options get handed to init, unless they look like
  * unused parameters (modprobe will find them in /proc/cmdline).
  */
-static int __init unknown_bootoption(char *param, char *val)
+static int __init unknown_bootoption(char *param, char *val,
+				const char *unused)
 {
 	/* Change NUL term back to "=", to make "param" the whole string. */
 	if (val) {
@@ -379,7 +380,7 @@ static noinline void __init_refok rest_init(void)
 }
 
 /* Check for early params. */
-static int __init do_early_param(char *param, char *val)
+static int __init do_early_param(char *param, char *val, const char *unused)
 {
 	const struct obs_kernel_param *p;
 
@@ -722,17 +723,18 @@ static initcall_t *initcall_levels[] __initdata = {
 };
 
 static char *initcall_level_names[] __initdata = {
-	"early parameters",
-	"core parameters",
-	"postcore parameters",
-	"arch parameters",
-	"subsys parameters",
-	"fs parameters",
-	"device parameters",
-	"late parameters",
+	"early",
+	"core",
+	"postcore",
+	"arch",
+	"subsys",
+	"fs",
+	"device",
+	"late",
 };
 
-static int __init ignore_unknown_bootoption(char *param, char *val)
+static int __init ignore_unknown_bootoption(char *param, char *val,
+					const char *doing)
 {
 	return 0;
 }
@@ -747,7 +749,7 @@ static void __init do_initcall_level(int level)
 		   static_command_line, __start___param,
 		   __stop___param - __start___param,
 		   level, level,
-		   ignore_unknown_bootoption);
+		   &ignore_unknown_bootoption);
 
 	for (fn = initcall_levels[level]; fn < initcall_levels[level+1]; fn++)
 		do_one_initcall(*fn);
@@ -757,8 +759,13 @@ static void __init do_initcalls(void)
 {
 	int level;
 
-	for (level = 0; level < ARRAY_SIZE(initcall_levels) - 1; level++)
+	for (level = 0; level < ARRAY_SIZE(initcall_levels) - 1; level++) {
+		pr_info("initlevel:%d=%s, %d registered initcalls\n",
+			level, initcall_level_names[level],
+			(int) (initcall_levels[level+1]
+				- initcall_levels[level]));
 		do_initcall_level(level);
+	}
 }
 
 /*

kernel/params.c

@@ -85,11 +85,13 @@ bool parameq(const char *a, const char *b)
 
 static int parse_one(char *param,
 		     char *val,
+		     const char *doing,
 		     const struct kernel_param *params,
 		     unsigned num_params,
 		     s16 min_level,
 		     s16 max_level,
-		     int (*handle_unknown)(char *param, char *val))
+		     int (*handle_unknown)(char *param, char *val,
+				     const char *doing))
 {
 	unsigned int i;
 	int err;
@@ -104,7 +106,7 @@ static int parse_one(char *param,
 			if (!val && params[i].ops->set != param_set_bool
 			    && params[i].ops->set != param_set_bint)
 				return -EINVAL;
-			pr_debug("They are equal!  Calling %p\n",
+			pr_debug("handling %s with %p\n", param,
 				params[i].ops->set);
 			mutex_lock(&param_lock);
 			err = params[i].ops->set(val, &params[i]);
@@ -114,11 +116,11 @@ static int parse_one(char *param,
 	}
 
 	if (handle_unknown) {
-		pr_debug("Unknown argument: calling %p\n", handle_unknown);
-		return handle_unknown(param, val);
+		pr_debug("doing %s: %s='%s'\n", doing, param, val);
+		return handle_unknown(param, val, doing);
 	}
 
-	pr_debug("Unknown argument `%s'\n", param);
+	pr_debug("Unknown argument '%s'\n", param);
 	return -ENOENT;
 }
 
@@ -175,28 +177,29 @@ static char *next_arg(char *args, char **param, char **val)
 }
 
 /* Args looks like "foo=bar,bar2 baz=fuz wiz". */
-int parse_args(const char *name,
+int parse_args(const char *doing,
 	       char *args,
 	       const struct kernel_param *params,
 	       unsigned num,
 	       s16 min_level,
 	       s16 max_level,
-	       int (*unknown)(char *param, char *val))
+	       int (*unknown)(char *param, char *val, const char *doing))
 {
 	char *param, *val;
 
-	pr_debug("Parsing ARGS: %s\n", args);
-
 	/* Chew leading spaces */
 	args = skip_spaces(args);
 
+	if (args && *args)
+		pr_debug("doing %s, parsing ARGS: '%s'\n", doing, args);
+
 	while (*args) {
 		int ret;
 		int irq_was_disabled;
 
 		args = next_arg(args, &param, &val);
 		irq_was_disabled = irqs_disabled();
-		ret = parse_one(param, val, params, num,
+		ret = parse_one(param, val, doing, params, num,
 				min_level, max_level, unknown);
 		if (irq_was_disabled && !irqs_disabled()) {
 			printk(KERN_WARNING "parse_args(): option '%s' enabled "
@@ -205,19 +208,19 @@ int parse_args(const char *name,
 		switch (ret) {
 		case -ENOENT:
 			printk(KERN_ERR "%s: Unknown parameter `%s'\n",
-			       name, param);
+			       doing, param);
 			return ret;
 		case -ENOSPC:
 			printk(KERN_ERR
 			       "%s: `%s' too large for parameter `%s'\n",
-			       name, val ?: "", param);
+			       doing, val ?: "", param);
 			return ret;
 		case 0:
 			break;
 		default:
 			printk(KERN_ERR
 			       "%s: `%s' invalid for parameter `%s'\n",
-			       name, val ?: "", param);
+			       doing, val ?: "", param);
 			return ret;
 		}
 	}