Too many poll_idle cpu calls in kernel 3.2 rc-series

[Nicolas Kalkhof]

the kernel v3.2 series shows excessive poll_idle calls during system idle phases causing the cpu
(mobile i7 2620M) to heat up and draw additional 10% more power. All kernel versions between
3.2-rc1 and 3.2-rc3 are affected. Perf Top and Powertop both show the same issue.
I've posted a similar bug report before: http://marc.info/?l=linux-kernel&m=132164909313594&w=2
and used perf top -U to verify the poll_idle calls as requested.

dmesg and kernel .config attached.

Could someone please confirm this issue?

Thanks and Regards
Nic

perf top -U shows:
Events: 30K cycles
Â97.88%Â [kernel]ÂÂ [k] poll_idle
 0.17% [kernel] [k] sdhci_irq
 0.08% [kernel] [k] unix_poll
 0.06% [kernel] [k] _raw_spin_lock_irqsave
 0.06% [kernel] [k] page_fault
 0.05% [kernel] [k] fget_light
 0.05% [kernel] [k] format_decode
 0.04% [kernel] [k] kmem_cache_alloc
 0.04% [kernel] [k] clear_page
 0.04% [kernel] [k] _raw_spin_unlock_irqrestore
 0.03% [kernel] [k] do_select
 0.03% [kernel] [k] seq_printf
 0.03% [kernel] [k] vfs_read
 0.03% [kernel] [k] _raw_spin_lock
 0.03% [kernel] [k] vsnprintf
 0.03% [kernel] [k] number.clone.1
 0.03% [kernel] [k] fput

Powertop shows:
nÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ Avg residencyÂÂÂÂÂÂ P-states (frequencies)
C0 (cpu running)ÂÂÂÂÂÂÂ ( 5.4%)ÂÂÂÂÂÂ Turbo ModeÂÂÂÂ 1.5%
pollingÂÂÂÂÂÂÂÂÂÂ 1.8ms (94.6%)ÂÂÂÂÂÂÂÂ 2.71 GhzÂÂÂÂ 0.1%
C1 mwaitÂÂÂÂÂÂÂÂÂ 0.0ms ( 0.0%)ÂÂÂÂÂÂÂÂ 2.21 GhzÂÂÂÂ 0.1%
C2 mwaitÂÂÂÂÂÂÂÂÂ 0.0ms ( 0.0%)ÂÂÂÂÂÂÂÂ 1400 MhzÂÂÂÂ 0.1%
C3 mwaitÂÂÂÂÂÂÂÂÂ 0.0ms ( 0.0%)ÂÂÂÂÂÂÂÂÂ 800 MhzÂÂÂ 98.2%
C4 mwaitÂÂÂÂÂÂÂÂÂ 0.0ms ( 0.0%)
Wakeups-from-idle per second : 529.4ÂÂÂ interval: 5.0s



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