'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. 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? Thanks, Venki >-----Original Message----- >From: Len Brown [mailto:lenb@xxxxxxxxxx] >Sent: Thursday, February 14, 2008 12:09 AM >To: Pallipadi, Venkatesh >Cc: linux-acpi@xxxxxxxxxxxxxxx >Subject: Re: [PATCH] ACPI, CPU_IDLE: Add more information >about C-states > >I'm confused by state0 -- why are usage and time non-zero -- >is this due to some residency there during initialization? > >I don't know if I like the looks of 2^32 - 1 as the power number... > >-Len > >[root@t61 cpuidle]# cat /proc/acpi/processor/CPU0/power >active state: C0 >max_cstate: C8 >bus master activity: 00000000 >maximum allowed latency: 2000000000 usec >states: > C1: type[C1] promotion[--] demotion[--] >latency[001] usage[00000000] duration[00000000000000000000] > C2: type[C2] promotion[--] demotion[--] >latency[001] usage[00000161] duration[00000000000000018522] > C3: type[C3] promotion[--] demotion[--] >latency[017] usage[00088238] duration[00000000002957934702] >[root@t61 cpuidle]# grep . */* >state0/desc:CPUIDLE CORE POLL IDLE >state0/latency:0 >state0/name:C0 >state0/power:4294967295 >state0/time:11623 >state0/usage:6 >state1/desc:ACPI FFH INTEL MWAIT 0x0 >state1/latency:1 >state1/name:C1 >state1/power:1000 >state1/time:0 >state1/usage:0 >state2/desc:ACPI FFH INTEL MWAIT 0x10 >state2/latency:1 >state2/name:C2 >state2/power:500 >state2/time:5104 >state2/usage:163 >state3/desc:ACPI FFH INTEL MWAIT 0x20 >state3/latency:17 >state3/name:C3 >state3/power:250 >state3/time:830738297 >state3/usage:89280 > >of course this isnt' new with this patch -- 2.6.25-rc1 looks as below: > >[root@t61 cpuidle]# cat /proc/acpi/processor/CPU0/power >active state: C0 >max_cstate: C8 >bus master activity: 00000000 >maximum allowed latency: 2000000000 usec >states: > C1: type[C1] promotion[--] demotion[--] >latency[001] usage[00000000] duration[00000000000000000000] > C2: type[C2] promotion[--] demotion[--] >latency[001] usage[00000202] duration[00000000000000028172] > C3: type[C3] promotion[--] demotion[--] >latency[017] usage[00026011] duration[00000000000264174466] >[root@t61 cpuidle]# grep . */* >state0/latency:0 >state0/name:C0 (poll idle) >state0/power:4294967295 >state0/time:35713 >state0/usage:6 >state1/latency:1 >state1/name:C1 >state1/power:1000 >state1/time:0 >state1/usage:0 >state2/latency:1 >state2/name:C2 >state2/power:500 >state2/time:7771 >state2/usage:203 >state3/latency:17 >state3/name:C3 >state3/power:250 >state3/time:74950731 >state3/usage:26286 > >and 2.6.24 showed no C0, as expected. > >[root@t61 cpuidle]# cat /proc/acpi/processor/CPU0/power >active state: C0 >max_cstate: C8 >bus master activity: 00000000 >maximum allowed latency: 2000 usec >states: > C1: type[C1] promotion[--] demotion[--] >latency[001] usage[00000030] duration[00000000000000000000] > C2: type[C2] promotion[--] demotion[--] >latency[001] usage[00000714] duration[00000000000000531448] > C3: type[C3] promotion[--] demotion[--] >latency[017] usage[00020563] duration[00000000000168147357] >[root@t61 cpuidle]# grep . */* >state0/latency:1 >state0/name:C1 >state0/power:1000 >state0/time:0 >state0/usage:30 >state1/latency:1 >state1/name:C2 >state1/power:500 >state1/time:148317 >state1/usage:719 >state2/latency:17 >state2/name:C3 >state2/power:250 >state2/time:48238649 >state2/usage:21034 >[root@t61 cpuidle]# > - 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
