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authorZhang Jiejing <jiejing.zhang@freescale.com>2010-11-22 17:14:32 +0800
committerZhang Jiejing <jiejing.zhang@freescale.com>2010-11-24 10:22:29 +0800
commit70df9e557c59c346f257a9b21418abf20045a571 (patch)
treef005aa5752041a8389f08c21ba71f4eb81f6e8a4 /kernel/power
parent838705ba857ca22c7c512331b6431651ed5a303d (diff)
ENGR00133978 PM: add time sensitive debug function to suspend & resume
There was some driver is slow on suspend/resume, but some embeded system like eReader,Cellphone are time sensitive,this commit will report the slow driver on suspend/resume, the default value is 500us(0.5ms) Also, the threshold can be change by modify '/sys/power/device_suspend_time_threshold' to change the threshold, it is in microsecond. The output is like: PM: device platform:soc-audio.2 suspend too slow, takes 606.696 msecs PM: device platform:mxc_sdc_fb.1 suspend too slow, takes 7.708 msecs Signed-off-by: Zhang Jiejing <jiejing.zhang@freescale.com>
Diffstat (limited to 'kernel/power')
-rw-r--r--kernel/power/Kconfig14
-rw-r--r--kernel/power/main.c32
2 files changed, 46 insertions, 0 deletions
diff --git a/kernel/power/Kconfig b/kernel/power/Kconfig
index ca6066a6952e..631de1141247 100644
--- a/kernel/power/Kconfig
+++ b/kernel/power/Kconfig
@@ -123,6 +123,20 @@ config PM_TEST_SUSPEND
You probably want to have your system's RTC driver statically
linked, ensuring that it's available when this test runs.
+config SUSPEND_DEVICE_TIME_DEBUG
+ bool "Warnning device suspend/resume takes too much time"
+ depends on SUSPEND && PM_DEBUG
+ default n
+ ---help---
+ This option will enable a timing function to check device
+ suspend time consumption, If the device takes more time that
+ the threshold(default 0.5 ms), it will print the device and
+ bus name on the console. You can change the threshold
+ on-the-fly by modify /sys/power/time_threshold the time unit
+ is in microsecond.
+
+ This options only for debug proprose, If in doubt, say N.
+
config SUSPEND_FREEZER
bool "Enable freezer for suspend to RAM/standby" \
if ARCH_WANTS_FREEZER_CONTROL || BROKEN
diff --git a/kernel/power/main.c b/kernel/power/main.c
index b58800b21fc0..0b9497851a9a 100644
--- a/kernel/power/main.c
+++ b/kernel/power/main.c
@@ -229,11 +229,43 @@ pm_trace_store(struct kobject *kobj, struct kobj_attribute *attr,
power_attr(pm_trace);
#endif /* CONFIG_PM_TRACE */
+#ifdef CONFIG_SUSPEND_DEVICE_TIME_DEBUG
+/*
+ * threshold of device suspend time consumption in microsecond(0.5ms), the
+ * driver suspend/resume time longer than this threshold will be
+ * print to console, 0 to disable */
+int device_suspend_time_threshold = 500;
+
+static ssize_t
+device_suspend_time_threshold_show(struct kobject *kobj,
+ struct kobj_attribute *attr, char *buf)
+{
+ return sprintf(buf, "%d\n", device_suspend_time_threshold);
+}
+
+static ssize_t
+device_suspend_time_threshold_store(struct kobject *kobj,
+ struct kobj_attribute *attr,
+ const char *buf, size_t n)
+{
+ int val;
+ if (sscanf(buf, "%d", &val) > 0) {
+ device_suspend_time_threshold = val;
+ return n;
+ }
+ return -EINVAL;
+}
+power_attr(device_suspend_time_threshold);
+#endif
+
static struct attribute * g[] = {
&state_attr.attr,
#ifdef CONFIG_PM_TRACE
&pm_trace_attr.attr,
#endif
+#ifdef CONFIG_SUSPEND_DEVICE_TIME_DEBUG
+ &device_suspend_time_threshold_attr.attr,
+#endif
#ifdef CONFIG_PM_SLEEP
&pm_async_attr.attr,
#ifdef CONFIG_PM_DEBUG