[PATCH] introduce task cgroup v2

[Paul Menage]

On Sun, Jun 15, 2008 at 6:32 PM, KOSAKI Motohiro
<kosaki.motohiro at jp.fujitsu.com> wrote:
>
> honestly, I used res_counter on early version.
> but I got bad performance.

Bad performance on the charge/uncharge?

The only difference I can see is that res_counter uses
spin_lock_irqsave()/spin_unlock_irqrestore(), and you're using plain
spin_lock()/spin_unlock().

Is the overhead of a pushf/cli/popf really going to matter compared
with the overhead of forking/exiting a task?

Or approaching this from the other side, does res_counter really need
irq-safe locking, or is it just being cautious?

Paul