On 04/02/2013 08:17 AM, jonghwa3.lee@xxxxxxxxxxx wrote: > On 2013년 04월 02일 14:00, Daniel Lezcano wrote: > >> On 04/01/2013 10:24 AM, Jonghwa Lee wrote: >>> This patch adds idle state time stamp to cpuidle device structure to >>> notify its current idle state. If last enter time is newer than last >>> exit time, then it means that the core is in idle now. >>> >>> Signed-off-by: Jonghwa Lee <jonghwa3.lee@xxxxxxxxxxx> >>> --- >> >> The patch description does not explain what problem you want to solve, >> how to solve it and the patch itself shows nothing. >> >> Could you elaborate ? > > > I'm sorry for lacking description. I supplement more. > > This patch does add time-stamp for idle enter/exit only nothing more. > The reason why I needed them is that I wanted to know current cpu idle > state. It is hard to know whether cpu is in idle or not now. Did you looked at: include/linux/sched.h:extern int idle_cpu(int cpu); ? > When I check the cpuidle state usage, sometimes the information is wrong. > Because it is updated only when the cpu exits the idle state. So while the > cpu is idling, the cpuidle state usage holds past one. Therefore I put > the time-stamp for cpuidle enter/exit for checking current idling and > calculating idle state usage correctly. > > I just make this patch temporary for my cpufreq governor work. So, it just > use time-stamp for all idle state together. After RFC working, I have a plan > to update this patch to use timestamp for each idle state. I suggest you look at the enter_idle / exit_idle function and make your governor to subscribe to the IDLE_START/EXIT notifiers. arch/x86/kernel/process.c These are defined for the x86 architecture, maybe worth to add it to another architecture. Thanks -- Daniel -- <http://www.linaro.org/> Linaro.org │ Open source software for ARM SoCs Follow Linaro: <http://www.facebook.com/pages/Linaro> Facebook | <http://twitter.com/#!/linaroorg> Twitter | <http://www.linaro.org/linaro-blog/> Blog -- To unsubscribe from this list: send the line "unsubscribe cpufreq" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
