[PATCH] suspend: add initcall_debug style timing for suspend/resume

Arjan van de Ven
2009-12-06T20:33:40Z

>From fcd52b97aa02f19baa570e4a62dfdfab0faed976 Mon Sep 17 00:00:00 2001
From: Arjan van de Ven <arjan@linux.intel.com>
Date: Sun, 6 Dec 2009 12:32:28 -0800
Subject: [PATCH] suspend: 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>
---
drivers/base/power/main.c | 29 +++++++++++++++++++++++++++++
include/linux/init.h | 2 ++
2 files changed, 31 insertions(+), 0 deletions(-)

diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c
index 8aa2443..2ad345c 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 +173,12 @@ static int pm_op(struct device *dev,
pm_message_t state)
{
int error = 0;
+ ktime_t calltime, delta, rettime;
+
+ if (initcall_debug) {
+ printk("calling %s+ @ %i\n", dev_name(dev), task_pid_nr(current));
+ calltime = ktime_get();
+ }

switch (state.event) {
#ifdef CONFIG_SUSPEND
@@ -219,6 +226,14 @@ static int pm_op(struct device *dev,
default:
error = -EINVAL;
}
+
+ if (initcall_debug) {
+ rettime = ktime_get();
+ delta = ktime_sub(rettime, calltime);
+ printk("initcall %s+ returned %d after %Ld usecs\n", dev_name(dev),
+ error, (unsigned long long) ktime_to_ns(delta) >> 10);
+ }
+
return error;
}

@@ -236,6 +251,12 @@ static int pm_noirq_op(struct device *dev,
pm_message_t state)
{
int error = 0;
+ ktime_t calltime, delta, rettime;
+
+ if (initcall_debug) {
+ printk("calling %s_i+ @ %i\n", dev_name(dev), task_pid_nr(current));
+ calltime = ktime_get();
+ }

switch (state.event) {
#ifdef CONFIG_SUSPEND
@@ -283,6 +304,14 @@ static int pm_noirq_op(struct device *dev,
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 @@ void prepare_namespace(void);

extern void (*late_time_init)(void);

+extern int initcall_debug;
+
#endif

#ifndef MODULE
--
1.6.2.5

--
Arjan van de Ven Intel Open Source Technology Centre
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