[PATCH v4 1/4] include/linux/suspend.h: Only show pm_pr_dbg messages at suspend/resume

From: Mario Limonciello
Date: Fri Jun 02 2023 - 15:33:02 EST


All uses in the kernel are currently already oriented around
suspend/resume. As some other parts of the kernel may also use these
messages in functions that could also be used outside of
suspend/resume, only enable in suspend/resume path.

Signed-off-by: Mario Limonciello <mario.limonciello@xxxxxxx>
---
v3->v4:
* add back do/while as it wasn't pointless. It fixes a warning.
---
include/linux/suspend.h | 8 +++++---
kernel/power/main.c | 6 ++++++
2 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/include/linux/suspend.h b/include/linux/suspend.h
index 1a0426e6761c..74f406c53ac0 100644
--- a/include/linux/suspend.h
+++ b/include/linux/suspend.h
@@ -555,6 +555,7 @@ static inline void unlock_system_sleep(unsigned int flags) {}
#ifdef CONFIG_PM_SLEEP_DEBUG
extern bool pm_print_times_enabled;
extern bool pm_debug_messages_on;
+extern bool pm_debug_messages_should_print(void);
static inline int pm_dyn_debug_messages_on(void)
{
#ifdef CONFIG_DYNAMIC_DEBUG
@@ -568,14 +569,14 @@ static inline int pm_dyn_debug_messages_on(void)
#endif
#define __pm_pr_dbg(fmt, ...) \
do { \
- if (pm_debug_messages_on) \
+ if (pm_debug_messages_should_print()) \
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) \
+ if (pm_debug_messages_should_print()) \
printk_deferred(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__); \
} while (0)
#else
@@ -593,7 +594,8 @@ static inline int pm_dyn_debug_messages_on(void)
/**
* pm_pr_dbg - print pm sleep debug messages
*
- * If pm_debug_messages_on is enabled, print message.
+ * If pm_debug_messages_on is enabled and the system is entering/leaving
+ * suspend, 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.
diff --git a/kernel/power/main.c b/kernel/power/main.c
index 3113ec2f1db4..daa535012e51 100644
--- a/kernel/power/main.c
+++ b/kernel/power/main.c
@@ -556,6 +556,12 @@ power_attr_ro(pm_wakeup_irq);

bool pm_debug_messages_on __read_mostly;

+bool pm_debug_messages_should_print(void)
+{
+ return pm_debug_messages_on && pm_suspend_target_state != PM_SUSPEND_ON;
+}
+EXPORT_SYMBOL_GPL(pm_debug_messages_should_print);
+
static ssize_t pm_debug_messages_show(struct kobject *kobj,
struct kobj_attribute *attr, char *buf)
{
--
2.34.1