On Thursday 14 February 2008 19:42, Pallipadi, Venkatesh wrote: > > >-----Original Message----- > >From: Len Brown [mailto:lenb@xxxxxxxxxx] > >Sent: Thursday, February 14, 2008 12:41 PM > >To: Pallipadi, Venkatesh > >Cc: linux-acpi@xxxxxxxxxxxxxxx > >Subject: Re: [PATCH] ACPI, CPU_IDLE: Add more information > >about C-states > > > >On Thursday 14 February 2008 11:52, Pallipadi, Venkatesh wrote: > >> > >> 'usage' is a counter that counts every time we get into poll_idle > >> routine. I also try to keep track of time spent in poll_idle, until > >> need_resched sends us out. That time is accumulated in 'time'. > >> Just have those to be consistent with other state and to be sure that > >> powertop kind of tools wont get confused. > > > >yes, the consistency is good. > >But my question is when and why we enter poll_idle at all. > > Ohh. Ok. May be the ladder governor used it for a while, before we > switch to menu governor. It should not increase later once system is > fully up? Do you see it increasing later? i haven't noticed it increase, but will look. > > > >> I agree with the 'power' number. I did not like that > >4294967295 there. > >> But, I had to put some number higher than other C-states, maximum > >> possible seemed logical. May be I can change the sysfs interface to > >> print <NULL> or something like that for power? > > > >I dunno. Somehow I like 0 to signify an unknown quantity > >rather than a huge number. If somebody actually looks at it > >with a program, they're going to have to special case either of them, > >and 0 seems simpler. > > > > Yes. But, if we have a 0W Cn state in future? :-). actually, the entire field is really worthless. we all know that BIOS writers just take the example code and use it multiple systems w/o changing these values. Perhaps we should re-cosider exposing this field, as it is mis-leading, at best... -len - To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
