sched/accounting: Re-use scheduler statistics for the root cgroup
Right now, after we collect tick statistics for user and system and store them in a well known location, we keep the same statistics again for cpuacct. Since cpuacct is hierarchical, the numbers for the root cgroup should be absolutely equal to the system-wide numbers. So it would be better to just use it: this patch changes cpuacct accounting in a way that the cpustat statistics are kept in a struct kernel_cpustat percpu array. In the root cgroup case, we just point it to the main array. The rest of the hierarchy walk can be totally disabled later with a static branch - but I am not doing it here. Signed-off-by: NGlauber Costa <glommer@parallels.com> Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Tuner <pjt@google.com> Link: http://lkml.kernel.org/r/1322498719-2255-4-git-send-email-glommer@parallels.comSigned-off-by: NIngo Molnar <mingo@elte.hu>
Showing
想要评论请 注册 或 登录