Re: [PATCH v6 22/24] x86/resctrl: Add cpu offline callback for resctrl work

Reinette Chatre
2023-10-03T21:23:21Z

Hi James,

On 9/14/2023 10:21 AM, James Morse wrote:
> The resctrl architecture specific code may need to free a domain when
> a CPU goes offline, it also needs to reset the CPUs PQR_ASSOC register.
> Amongst other things, the resctrl filesystem code needs to clear this
> CPU from the cpu_mask of any control and monitor groups.
>
> Currently this is all done in core.c and called from
> resctrl_offline_cpu(), making the split between architecture and
> filesystem code unclear.
>
> Move the filesystem work to remove the CPU from the control and monitor
> groups into a filesystem helper called resctrl_offline_cpu(), and rename
> the one in core.c resctrl_arch_offline_cpu().
>
> The rdtgroup_mutex is unlocked and locked again in the call in
> preparation for changing the locking rules for the architecture
> code.

This last paragraph may cause some confusion since this refactoring
is not changing any current locking. I'll defer to you if you prefer
to keep it.

>
> Reviewed-by: Shaopeng Tan <tan.shaopeng@fujitsu.com>
> Tested-by: Shaopeng Tan <tan.shaopeng@fujitsu.com>
> Tested-By: Peter Newman <peternewman@google.com>
> Signed-off-by: James Morse <james.morse@arm.com>
> ---

Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>

Reinette