Commit ce1cb680 authored by David Cohen's avatar David Cohen Committed by Rafael J. Wysocki
Browse files

PM: sleep: enable dynamic debug support within pm_pr_dbg() 



Currently pm_pr_dbg() is used to filter kernel pm debug messages based
on pm_debug_messages_on flag. The problem is if we enable/disable this
flag it will affect all pm_pr_dbg() calls at once, so we can't
individually control them.

This patch changes pm_pr_dbg() implementation as such:

 - If pm_debug_messages_on is enabled, print the message.
 - If pm_debug_messages_on is disabled and CONFIG_DYNAMIC_DEBUG is
   enabled, only print the messages explicitly enabled on
   /sys/kernel/debug/dynamic_debug/control.
 - If pm_debug_messages_on is disabled and CONFIG_DYNAMIC_DEBUG is
   disabled, don't print the message.

Signed-off-by: default avatarDavid Cohen <dacohen@pm.me>
Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
parent ae20cb9a

include/linux/suspend.h

+39 −5
Original line number Diff line number Diff line
@@ -542,22 +542,56 @@ static inline void unlock_system_sleep(void) {} 
#ifdef CONFIG_PM_SLEEP_DEBUG

extern bool pm_print_times_enabled;

extern bool pm_debug_messages_on;

extern __printf(2, 3) void __pm_pr_dbg(bool defer, const char *fmt, ...);

static inline int pm_dyn_debug_messages_on(void)

{

#ifdef CONFIG_DYNAMIC_DEBUG

	return 1;

#else

	return 0;

#endif

}

#ifndef pr_fmt

#define pr_fmt(fmt) "PM: " fmt

#endif

#define __pm_pr_dbg(fmt, ...)					\

	do {							\

		if (pm_debug_messages_on)			\

			printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__);	\

		else if (pm_dyn_debug_messages_on())		\

			pr_debug(fmt, ##__VA_ARGS__);	\

	} while (0)

#define __pm_deferred_pr_dbg(fmt, ...)				\

	do {							\

		if (pm_debug_messages_on)			\

			printk_deferred(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__);	\

	} while (0)

#else

#define pm_print_times_enabled	(false)

#define pm_debug_messages_on	(false)



#include <linux/printk.h>



#define __pm_pr_dbg(defer, fmt, ...) \

	no_printk(KERN_DEBUG fmt, ##__VA_ARGS__)

#define __pm_pr_dbg(fmt, ...) \

	no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)

#define __pm_deferred_pr_dbg(fmt, ...) \

	no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)

#endif



/**

 * pm_pr_dbg - print pm sleep debug messages

 *

 * If pm_debug_messages_on is enabled, print message.

 * If pm_debug_messages_on is disabled and CONFIG_DYNAMIC_DEBUG is enabled,

 *	print message only from instances explicitly enabled on dynamic debug's

 *	control.

 * If pm_debug_messages_on is disabled and CONFIG_DYNAMIC_DEBUG is disabled,

 *	don't print message.

 */

#define pm_pr_dbg(fmt, ...) \

	__pm_pr_dbg(false, fmt, ##__VA_ARGS__)

	__pm_pr_dbg(fmt, ##__VA_ARGS__)



#define pm_deferred_pr_dbg(fmt, ...) \

	__pm_pr_dbg(true, fmt, ##__VA_ARGS__)

	__pm_deferred_pr_dbg(fmt, ##__VA_ARGS__)



#ifdef CONFIG_PM_AUTOSLEEP

kernel/power/main.c

+0 −29
Original line number Diff line number Diff line
@@ -545,35 +545,6 @@ static int __init pm_debug_messages_setup(char *str) 
}

__setup("pm_debug_messages", pm_debug_messages_setup);



/**

 * __pm_pr_dbg - Print a suspend debug message to the kernel log.

 * @defer: Whether or not to use printk_deferred() to print the message.

 * @fmt: Message format.

 *

 * The message will be emitted if enabled through the pm_debug_messages

 * sysfs attribute.

 */

void __pm_pr_dbg(bool defer, const char *fmt, ...)

{

	struct va_format vaf;

	va_list args;



	if (!pm_debug_messages_on)

		return;



	va_start(args, fmt);



	vaf.fmt = fmt;

	vaf.va = &args;



	if (defer)

		printk_deferred(KERN_DEBUG "PM: %pV", &vaf);

	else

		printk(KERN_DEBUG "PM: %pV", &vaf);



	va_end(args);

}



#else /* !CONFIG_PM_SLEEP_DEBUG */

static inline void pm_print_times_init(void) {}

#endif /* CONFIG_PM_SLEEP_DEBUG */