PM: Add initcall_debug style timing for suspend/resume
In order to diagnose overall suspend/resume times, we need
basic instrumentation to break down the total time into per
device timing, similar to initcall_debug.
This patch adds the basic timing instrumentation, needed
for a scritps/bootgraph.pl equivalent or humans.
The bootgraph.pl program is still a work in progress, but
is far enough along to know that this patch is sufficient.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c
index 8aa2443..30f0cee 100644
--- a/drivers/base/power/main.c
+++ b/drivers/base/power/main.c
@@ -25,6 +25,7 @@
#include <linux/resume-trace.h>
#include <linux/rwsem.h>
#include <linux/interrupt.h>
+#include <linux/sched.h>
#include "../base.h"
#include "power.h"
@@ -172,6 +173,13 @@
pm_message_t state)
{
int error = 0;
+ ktime_t calltime, delta, rettime;
+
+ if (initcall_debug) {
+ pr_info("calling %s+ @ %i\n",
+ dev_name(dev), task_pid_nr(current));
+ calltime = ktime_get();
+ }
switch (state.event) {
#ifdef CONFIG_SUSPEND
@@ -219,6 +227,14 @@
default:
error = -EINVAL;
}
+
+ if (initcall_debug) {
+ rettime = ktime_get();
+ delta = ktime_sub(rettime, calltime);
+ pr_info("call %s+ returned %d after %Ld usecs\n", dev_name(dev),
+ error, (unsigned long long)ktime_to_ns(delta) >> 10);
+ }
+
return error;
}
@@ -236,6 +252,13 @@
pm_message_t state)
{
int error = 0;
+ ktime_t calltime, delta, rettime;
+
+ if (initcall_debug) {
+ pr_info("calling %s_i+ @ %i\n",
+ dev_name(dev), task_pid_nr(current));
+ calltime = ktime_get();
+ }
switch (state.event) {
#ifdef CONFIG_SUSPEND
@@ -283,6 +306,14 @@
default:
error = -EINVAL;
}
+
+ if (initcall_debug) {
+ rettime = ktime_get();
+ delta = ktime_sub(rettime, calltime);
+ printk("initcall %s_i+ returned %d after %Ld usecs\n", dev_name(dev),
+ error, (unsigned long long)ktime_to_ns(delta) >> 10);
+ }
+
return error;
}
diff --git a/include/linux/init.h b/include/linux/init.h
index ff8bde5..ab1d31f 100644
--- a/include/linux/init.h
+++ b/include/linux/init.h
@@ -149,6 +149,8 @@
extern void (*late_time_init)(void);
+extern int initcall_debug;
+
#endif
#ifndef MODULE