From mboxrd@z Thu Jan  1 00:00:00 1970
From: Tejun Heo <tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
Subject: Re: [PATCH] cgroup: add tracepoints to track cgroup events
Date: Thu, 21 Aug 2014 09:13:30 -0500
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To: Andrea Righi <andrea-oIIqvOZpAevzfdHfmsDf5w@public.gmane.org>
Cc: Li Zefan <lizefan-hv44wF8Li93QT0dZR+AlfA@public.gmane.org>, Steven Rostedt <rostedt-nx8X9YLhiw1AfugRpC6u6w@public.gmane.org>, Ingo Molnar <mingo-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>, cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Matt Heaton <matt-oIIqvOZpAevzfdHfmsDf5w@public.gmane.org>

Hello,

On Wed, Aug 20, 2014 at 09:46:25PM -0600, Andrea Righi wrote:
> This patch adds the following tracepoints:
>  o trace_cgroup_create       when a new cgroup is created
>  o trace_cgroup_destroy      when a cgroup is removed
>  o trace_cgroup_task_migrate when a task/thread is moved from a cgroup to another
> 
> The purpose of these tracepoints is to identify and help cgroup "managers" to
> diagnose problems and detect when they are doing an excessive amount of work.

Using TPs for this looks like a really roundabout way of doing this
when the whole interface is based on filesystem.  Extending
kernfs_notity to support directory events seems like a better way to
do this.

Thanks.

-- 
tejun