tree f0a506318d8ea653057d6f99387c163b526ebeb3
parent b3a6d2a54b8be331b36d849577a716867895ca75
author Will Schmidt <will_schmidt@vnet.ibm.com> 1176821086 +1000
committer Paul Mackerras <paulus@samba.org> 1177414303 +1000

[POWERPC] hvc_console: Polling mode timer backoff

Add a back-off mechanism to hvc_console's polling logic.   This change
drops the timers/second ratio from ~90 to ~1/2 while the console is
idle.
This change is most noticeable when watching /proc/timer_stats output.

This only affects when the hvc_console is running in poll mode, i.e.
power4 and cell systems.

I've tested on Power4, Michael Ellerman has both contributed to the
patch and tested on cell.

Signed-off-by: Will Schmidt <will_schmidt@vnet.ibm.com>
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Linas Vepstas <linas@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>