tree 4180d3edff8377f16ff0ad95f97189f2943fa3a5
parent 2f97cd3912428f5044fa7715293a69349fc455fa
author Jake Moilanen <moilanen@austin.ibm.com> 1181251631 +1000
committer Paul Mackerras <paulus@samba.org> 1181824198 +1000

[POWERPC] Donate idle CPU cycles on dedicated partitions

A Power6 can give up CPU cycles on a dedicated CPU (as opposed to a
shared CPU) to other shared processors if the administrator asks for it
(via the HMC).

This enables that to work properly on P6.

This just involves setting a bit in the CAS structure as well as the
VPA.  To donate cycles, a CPU has to have all SMT threads idle and
have the donate bit set in the VPA.  Then call H_CEDE.

The reason why shared processors just aren't used is because dedicated
CPUs are guaranteed an actual processor, yet the system is still able to
increase the capacity of the shared CPU pool.

Also rename the VPA's cpuctls_task_attrs field to a more accurate name.

Signed-off-by: Jake Moilanen <moilanen@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>