From 43681cabc16498709e63809380c736e801f08677 Mon Sep 17 00:00:00 2001 From: Zhang Jiejing Date: Mon, 22 Nov 2010 17:14:32 +0800 Subject: 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 the default state of suspend driver is default off, if you want to debug the suspend time, echo time in microsecond(u Second) to /sys/powe/device_suspend_time_threshold eg: I want to know which driver suspend & resume takes more that 0.5 ms (500 us), you can just : ehco 500 > /sys/power/device_suspend_time_threshold Signed-off-by: Zhang Jiejing --- kernel/power/Kconfig | 25 +++++++++++++++++++++++++ kernel/power/main.c | 36 ++++++++++++++++++++++++++++++++++++ 2 files changed, 61 insertions(+) (limited to 'kernel') diff --git a/kernel/power/Kconfig b/kernel/power/Kconfig index 87f4d24b55b0..c1a820a36861 100644 --- a/kernel/power/Kconfig +++ b/kernel/power/Kconfig @@ -7,6 +7,31 @@ config SUSPEND powered and thus its contents are preserved, such as the suspend-to-RAM state (e.g. the ACPI S3 state). +config PM_TEST_SUSPEND + bool "Test suspend/resume and wakealarm during bootup" + depends on SUSPEND && PM_DEBUG && RTC_CLASS=y + ---help--- + This option will let you suspend your machine during bootup, and + make it wake up a few seconds later using an RTC wakeup alarm. + Enable this with a kernel parameter like "test_suspend=mem". + + 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 2981af4ce7cb..b7d0e301e43b 100644 --- a/kernel/power/main.c +++ b/kernel/power/main.c @@ -297,12 +297,48 @@ power_attr(pm_trace_dev_match); #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; + +static ssize_t +device_suspend_time_threshold_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + if (device_suspend_time_threshold == 0) + return sprintf(buf, "off\n"); + else + return sprintf(buf, "%d usecs\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, &pm_trace_dev_match_attr.attr, #endif +#ifdef CONFIG_SUSPEND_DEVICE_TIME_DEBUG + &device_suspend_time_threshold_attr.attr, +#endif #ifdef CONFIG_PM_SLEEP &pm_async_attr.attr, &wakeup_count_attr.attr, -- cgit v1.2.3