LKML Archive on lore.kernel.org
help / color / mirror / Atom feed
From: "Paul Menage" <menage@google.com>
To: balbir@in.ibm.com
Cc: akpm@osdl.org, pj@sgi.com, sekharan@us.ibm.com, dev@sw.ru,
	xemul@sw.ru, serue@us.ibm.com, vatsa@in.ibm.com,
	ckrm-tech@lists.sourceforge.net, linux-kernel@vger.kernel.org,
	rohitseth@google.com, mbligh@google.com, winget@google.com,
	containers@lists.osdl.org, devel@openvz.org
Subject: Re: [ckrm-tech] [PATCH 3/6] containers: Add generic multi-subsystem API to containers
Date: Thu, 11 Jan 2007 14:53:55 -0800	[thread overview]
Message-ID: <6599ad830701111453t62bec38cl9534263002f48a15@mail.gmail.com> (raw)
In-Reply-To: <45A50CA5.6070101@in.ibm.com>

On 1/10/07, Balbir Singh <balbir@in.ibm.com> wrote:
> Paul Menage wrote:
> > +/* The set of hierarchies in use. Hierarchy 0 is the "dummy
> > + * container", reserved for the subsystems that are otherwise
> > + * unattached - it never has more than a single container, and all
> > + * tasks are part of that container. */
> > +
> > +static struct containerfs_root rootnode[CONFIG_MAX_CONTAINER_HIERARCHIES];
> > +
> > +/* dummytop is a shorthand for the dummy hierarchy's top container */
> > +#define dummytop (&rootnode[0].top_container)
> > +
>
> With these changes, is there a generic way to determine the root container
> for the hierarchy the subsystem is in? Calls to ->create() pass the dummytop
> container.

There are two places that the subsystem create() function is called -
the first is during the subsystem registration, to create the
subsystem state for the root container. That one passes in dummytop
since that is the container that all subsystems start attached to.

For clarification, the default (dummy) hierarchy is a placeholder for
subsystems that aren't bound to a hierarchy. It always contains
exactly one container (dummytop) and all processes are members of that
container. It isn't reference-counted, since it can never go away, and
it can never have any subcontainers.

When a real subcontainer is created (which must be after a subsystem
has been bound to a hierarchy via a filesystem mount), the new
subcontainer is passed in. From there you can follow the top_container
field in the subcontainer, which leads to the root of the hierarchy.

Andrew has suggested that I need to document this better :-)

Paul

  reply	other threads:[~2007-01-11 22:54 UTC|newest]

Thread overview: 36+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2006-12-22 14:14 [PATCH 0/6] containers: Generic Process Containers (V6) Paul Menage
2006-12-22 14:14 ` [PATCH 1/6] containers: Generic container system abstracted from cpusets code Paul Menage
2006-12-30 13:10   ` Eric W. Biederman
2006-12-31  5:17     ` Paul Jackson
2007-01-02 22:15     ` Paul Menage
2006-12-22 14:14 ` [PATCH 2/6] containers: Cpusets hooked into containers Paul Menage
2006-12-22 14:14 ` [PATCH 3/6] containers: Add generic multi-subsystem API to containers Paul Menage
2007-01-10 15:56   ` [ckrm-tech] " Balbir Singh
2007-01-11 22:53     ` Paul Menage [this message]
2007-01-12  6:29       ` Balbir Singh
2007-01-12  8:10         ` Paul Menage
2007-01-12  8:22           ` Balbir Singh
2007-01-20 17:27           ` Balbir Singh
2006-12-22 14:14 ` [PATCH 4/6] containers: Simple CPU accounting container subsystem Paul Menage
2007-01-10 14:21   ` [ckrm-tech] " Balbir Singh
2007-01-12  0:33     ` Paul Menage
2007-01-12  6:24       ` Balbir Singh
2007-01-12  8:15         ` Paul Menage
2007-01-12  8:26           ` Balbir Singh
2007-01-12 17:32             ` Paul Menage
2007-01-15  9:01       ` [PATCH 0/1] Add mount/umount callbacks to containers (Re: [ckrm-tech] [PATCH 4/6] containers: Simple CPU accounting container subsystem) Balbir Singh
2007-01-15  9:04         ` [PATCH 1/1] Fix a panic while mouting containers on powerpc and some other small cleanups " Balbir Singh
2007-01-15  9:22           ` Paul Menage
2007-01-15  9:51             ` [ckrm-tech] [PATCH 1/1] Fix a panic while mouting containers on powerpc and some other small cleanups (Re: " Balbir Singh
2007-01-15 10:01               ` Paul Menage
2007-01-15 10:10                 ` Balbir Singh
2006-12-22 14:14 ` [PATCH 5/6] containers: Resource Groups over generic containers Paul Menage
2006-12-22 14:14 ` [PATCH 6/6] containers: BeanCounters over generic process containers Paul Menage
2006-12-23 19:49   ` Herbert Poetzl
2006-12-24 11:32     ` Paul Menage
2006-12-25 10:16     ` Kirill Korotaev
2006-12-26  0:54       ` Paul Menage
2006-12-25 10:35     ` Pavel Emelianov
2007-01-03 14:43 ` [PATCH 0/6] containers: Generic Process Containers (V6) Serge E. Hallyn
2007-01-05  0:25   ` Paul Menage
2007-01-12 18:42     ` Serge E. Hallyn

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=6599ad830701111453t62bec38cl9534263002f48a15@mail.gmail.com \
    --to=menage@google.com \
    --cc=akpm@osdl.org \
    --cc=balbir@in.ibm.com \
    --cc=ckrm-tech@lists.sourceforge.net \
    --cc=containers@lists.osdl.org \
    --cc=dev@sw.ru \
    --cc=devel@openvz.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mbligh@google.com \
    --cc=pj@sgi.com \
    --cc=rohitseth@google.com \
    --cc=sekharan@us.ibm.com \
    --cc=serue@us.ibm.com \
    --cc=vatsa@in.ibm.com \
    --cc=winget@google.com \
    --cc=xemul@sw.ru \
    --subject='Re: [ckrm-tech] [PATCH 3/6] containers: Add generic multi-subsystem API to containers' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).