[PATCH] (was: Re: [PATCH v2] power: add knob for printing device resume times)

["Rafael J. Wysocki" <rjw@sisk.pl>]

On Saturday, June 16, 2012, Rafael J. Wysocki wrote:
> On Friday, June 15, 2012, Greg KH wrote:
> > On Fri, Jun 15, 2012 at 12:00:20PM +0200, Rafael J. Wysocki wrote:
> > > On Friday, June 15, 2012, Greg KH wrote:
> > > > On Wed, May 23, 2012 at 09:45:32AM -0700, Sameer Nanda wrote:
> > > > > Added a new knob called /sys/power/pm_print_times. Setting it to 1
> > > > > enables printing of time taken by devices to suspend and resume.
> > > > > Setting it to 0 disables this printing (unless overridden by
> > > > > initcall_debug kernel command line option).
> > > > > 
> > > > > Signed-off-by: Sameer Nanda <snanda@chromium.org>
> > > > > cc: Greg KH <gregkh@linuxfoundation.org>
> > > > > cc: Rafael J. Wysocki <rjw@sisk.pl>
> > > > > cc: Steven Rostedt <rostedt@goodmis.org>
> > > > > ---
> > > > >  Documentation/ABI/testing/sysfs-power |   13 ++++++++++++
> > > > >  drivers/base/power/main.c             |    4 +-
> > > > >  drivers/base/power/power.h            |   11 ++++++++++
> > > > >  kernel/power/main.c                   |   34 +++++++++++++++++++++++++++++++++
> > > > >  4 files changed, 60 insertions(+), 2 deletions(-)
> > > > 
> > > > This patch fails against the linux-next tree, care to fix it up so that
> > > > I can apply it?
> > > 
> > > I'd prefer it to go through my tree if you don't mind.
> > 
> > Not at all, feel free to put:
> > 
> > Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> > 
> > When it shows up again.
> 
> I've just used the original one, it only needed a documentation merge conflict
> fixed.
> 
> Queued up for 3.6.

I propose the following patch on top of this one.  The details are in the
changelog.

If anyone has any objections, please let me know.

Thanks,
Rafael

---
From: Rafael J. Wysocki <rjw@sisk.pl>
Subject: PM / Sleep: Separate printing suspend times from initcall_debug

Change the behavior of the newly introduced
/sys/power/pm_print_times attribute so that its initial value
depends on initcall_debug, but setting it to 0 will cause device
suspend/resume times not to be printed, even if initcall_debug has
been set.  This way, the people who use initcall_debug for reasons
other than PM debugging will be able to switch the suspend/resume
times printing off, if need be.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
---
 drivers/base/power/main.c  |    4 ++--
 drivers/base/power/power.h |   11 -----------
 include/linux/suspend.h    |    4 ++++
 kernel/power/main.c        |   14 +++++++++++---
 4 files changed, 17 insertions(+), 16 deletions(-)

Index: linux/kernel/power/main.c
===================================================================
--- linux.orig/kernel/power/main.c
+++ linux/kernel/power/main.c
@@ -139,7 +139,7 @@ power_attr(pm_test);
  * show() returns whether printing of suspend and resume times is enabled.
  * store() accepts 0 or 1.  0 disables printing and 1 enables it.
  */
-int pm_print_times_enabled;
+bool pm_print_times_enabled;
 
 static ssize_t pm_print_times_show(struct kobject *kobj,
 				   struct kobj_attribute *attr, char *buf)
@@ -159,12 +159,19 @@ static ssize_t pm_print_times_store(stru
 	if (val > 1)
 		return -EINVAL;
 
-	pm_print_times_enabled = val;
+	pm_print_times_enabled = !!val;
 	return n;
 }
 
+static inline void pm_print_times_init(void)
+{
+	pm_print_times_enabled = !!initcall_debug;
+}
+
 power_attr(pm_print_times);
-#endif /* CONFIG_PM_DEBUG */
+#else /* !CONFIG_PM_DEBUG */
+static inline void pm_print_times_init(void) {}
+#endif /* !CONFIG_PM_DEBUG */
 
 #ifdef CONFIG_DEBUG_FS
 static char *suspend_step_name(enum suspend_stat_step step)
@@ -599,6 +606,7 @@ static int __init pm_init(void)
 	error = sysfs_create_group(power_kobj, &attr_group);
 	if (error)
 		return error;
+	pm_print_times_init();
 	return pm_autosleep_init();
 }
 
Index: linux/include/linux/suspend.h
===================================================================
--- linux.orig/include/linux/suspend.h
+++ linux/include/linux/suspend.h
@@ -387,6 +387,8 @@ static inline void unlock_system_sleep(v
 	mutex_unlock(&pm_mutex);
 }
 
+extern bool pm_print_times_enabled;
+
 #else /* !CONFIG_PM_SLEEP */
 
 static inline int register_pm_notifier(struct notifier_block *nb)
@@ -406,6 +408,8 @@ static inline bool pm_wakeup_pending(voi
 static inline void lock_system_sleep(void) {}
 static inline void unlock_system_sleep(void) {}
 
+#define pm_print_times_enabled	(false)
+
 #endif /* !CONFIG_PM_SLEEP */
 
 #ifdef CONFIG_PM_AUTOSLEEP
Index: linux/drivers/base/power/main.c
===================================================================
--- linux.orig/drivers/base/power/main.c
+++ linux/drivers/base/power/main.c
@@ -166,7 +166,7 @@ static ktime_t initcall_debug_start(stru
 {
 	ktime_t calltime = ktime_set(0, 0);
 
-	if (pm_print_times) {
+	if (pm_print_times_enabled) {
 		pr_info("calling  %s+ @ %i, parent: %s\n",
 			dev_name(dev), task_pid_nr(current),
 			dev->parent ? dev_name(dev->parent) : "none");
@@ -181,7 +181,7 @@ static void initcall_debug_report(struct
 {
 	ktime_t delta, rettime;
 
-	if (pm_print_times) {
+	if (pm_print_times_enabled) {
 		rettime = ktime_get();
 		delta = ktime_sub(rettime, calltime);
 		pr_info("call %s+ returned %d after %Ld usecs\n", dev_name(dev),
Index: linux/drivers/base/power/power.h
===================================================================
--- linux.orig/drivers/base/power/power.h
+++ linux/drivers/base/power/power.h
@@ -85,14 +85,3 @@ static inline int pm_qos_sysfs_add(struc
 static inline void pm_qos_sysfs_remove(struct device *dev) {}
 
 #endif
-
-#ifdef CONFIG_PM_DEBUG
-
-extern int pm_print_times_enabled;
-#define pm_print_times (initcall_debug || pm_print_times_enabled)
-
-#else /* CONFIG_PM_DEBUG */
-
-#define pm_print_times initcall_debug
-
-#endif /* CONFIG_PM_DEBUG */