Re: [PATCH 4/9] perf tools: Maintain cgroup hierarchy

[Jiri Olsa]

On Tue, Jan 07, 2020 at 10:34:56PM +0900, Namhyung Kim wrote:
> Each cgroup is kept in the global cgroup_tree sorted by the cgroup id.
> Hist entries have cgroup id can compare it directly and later it can
> be used to find a group name using this tree.
> 
> Signed-off-by: Namhyung Kim <namhyung@xxxxxxxxxx>
> ---
>  tools/perf/util/cgroup.c  | 72 +++++++++++++++++++++++++++++++++++++++
>  tools/perf/util/cgroup.h  | 15 +++++---
>  tools/perf/util/machine.c |  7 ++++
>  tools/perf/util/session.c |  4 +++
>  4 files changed, 94 insertions(+), 4 deletions(-)
> 
> diff --git a/tools/perf/util/cgroup.c b/tools/perf/util/cgroup.c
> index 4881d4af3381..4e8ef1db0c94 100644
> --- a/tools/perf/util/cgroup.c
> +++ b/tools/perf/util/cgroup.c
> @@ -13,6 +13,8 @@
>  
>  int nr_cgroups;
>  
> +static struct rb_root cgroup_tree = RB_ROOT;

I think we shoud carry that in 'struct perf_env' 

jirka