Re: [PATCH v2] cgroup: move cgroup_subsys_state parent field for cache locality

From: Tejun Heo
Date: Mon Apr 10 2017 - 20:05:46 EST


Hello,

On Thu, Apr 06, 2017 at 06:47:57PM -0700, Todd Poynor wrote:
> From: Todd Poynor <toddpoynor@xxxxxxxxxx>
>
> Various structures embed a struct cgroup_subsys_state, typically at
> the top of the containing structure. It is common for code that
> accesses the structures to perform operations that iterate over the
> chain of parent css pointers, also accessing data in each containing
> structure. In particular, struct cpuacct is used by fairly hot code
> paths in the scheduler such as cpuacct_charge().
>
> Move the parent css pointer field to the end of the structure to
> increase the chances of residing in the same cache line as the data
> from the containing structure.
>
> Signed-off-by: Todd Poynor <toddpoynor@xxxxxxxxxx>

Applied to cgroup/for-4.12.

Thanks.

--
tejun