All of lore.kernel.org
 help / color / mirror / Atom feed
From: ebiederm@xmission.com (Eric W. Biederman)
To: Tejun Heo <tj@kernel.org>
Cc: Michal Hocko <mhocko@kernel.org>,
	Andrew Morton <akpm@linux-foundation.org>,
	Johannes Weiner <hannes@cmpxchg.org>,
	Kirill Tkhai <ktkhai@virtuozzo.com>,
	peterz@infradead.org, viro@zeniv.linux.org.uk, mingo@kernel.org,
	paulmck@linux.vnet.ibm.com, keescook@chromium.org,
	riel@redhat.com, tglx@linutronix.de,
	kirill.shutemov@linux.intel.com, marcos.souza.org@gmail.com,
	hoeun.ryu@gmail.com, pasha.tatashin@oracle.com,
	gs051095@gmail.com, dhowells@redhat.com, rppt@linux.vnet.ibm.com,
	linux-kernel@vger.kernel.org,
	Balbir Singh <balbir@linux.vnet.ibm.com>,
	Oleg Nesterov <oleg@redhat.com>
Subject: Re: [RFC][PATCH 1/2] memcg: Ensure every task that uses an mm is in the same memory cgroup
Date: Fri, 01 Jun 2018 13:11:59 -0500	[thread overview]
Message-ID: <87bmcuv0k0.fsf@xmission.com> (raw)
In-Reply-To: <20180601165034.GX1351649@devbig577.frc2.facebook.com> (Tejun Heo's message of "Fri, 1 Jun 2018 09:50:34 -0700")

Tejun Heo <tj@kernel.org> writes:

>> This effectively forbids process with mm's shared processes being migrated.
>> Although enabling the control file might work.
>
> So, I don't think we need to support putting tasks which share a mm in
> different cgroups.  That said, if we're gonna put in that restriction,
> I think it should be in cgroup core rather than memcg can_attach.  The
> only thing we'd need to do is widening what cgroup migration considers
> to be a process.

Widening the definition of a process sounds good.  The memory control
group code would still need a way to forbid these in cgroup v1 mode,
when someone uses the task file.

Using widening instead of denying should reduce the risk of introducing
a regression.

The only reason I support the crazy case in my earlier patch is so that
we can have this discussion and in case we do cause a regression with
this change the previous algorithmic cleanup won't have to be reverted
as well.

Eric

  reply	other threads:[~2018-06-01 18:12 UTC|newest]

Thread overview: 96+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-04-26 11:00 [PATCH 0/4] exit: Make unlikely case in mm_update_next_owner() more scalable Kirill Tkhai
2018-04-26 11:00 ` [PATCH 1/4] exit: Move read_unlock() up in mm_update_next_owner() Kirill Tkhai
2018-04-26 15:01   ` Oleg Nesterov
2018-04-26 11:00 ` [PATCH 2/4] exit: Use rcu instead of get_task_struct() " Kirill Tkhai
2018-04-26 11:00 ` [PATCH 3/4] exit: Rename assign_new_owner label " Kirill Tkhai
2018-04-26 11:01 ` [PATCH 4/4] exit: Lockless iteration over task list " Kirill Tkhai
2018-04-26 12:35   ` Andrea Parri
2018-04-26 13:52     ` Kirill Tkhai
2018-04-26 15:20       ` Peter Zijlstra
2018-04-26 15:56         ` Kirill Tkhai
2018-04-26 15:20       ` Peter Zijlstra
2018-04-26 16:04         ` Kirill Tkhai
2018-04-26 15:29       ` Andrea Parri
2018-04-26 16:11         ` Kirill Tkhai
2018-04-26 13:07 ` [PATCH 0/4] exit: Make unlikely case in mm_update_next_owner() more scalable Michal Hocko
2018-04-26 13:52   ` Oleg Nesterov
2018-04-26 14:07   ` Kirill Tkhai
2018-04-26 15:10     ` Oleg Nesterov
2018-04-26 16:19   ` Eric W. Biederman
2018-04-26 19:28     ` Michal Hocko
2018-04-27  7:08       ` Michal Hocko
2018-04-27 18:05         ` Eric W. Biederman
2018-05-01 17:22           ` Eric W. Biederman
2018-05-01 17:35             ` [RFC][PATCH] memcg: Replace mm->owner with mm->memcg Eric W. Biederman
2018-05-02  8:47               ` Michal Hocko
2018-05-02 13:20                 ` Johannes Weiner
2018-05-02 14:05                   ` Eric W. Biederman
2018-05-02 19:21                   ` [PATCH] " Eric W. Biederman
2018-05-02 21:04                     ` Andrew Morton
2018-05-02 21:35                       ` Eric W. Biederman
2018-05-03 13:33                     ` Oleg Nesterov
2018-05-03 14:39                       ` Eric W. Biederman
2018-05-04 14:20                         ` Oleg Nesterov
2018-05-04 14:36                           ` Eric W. Biederman
2018-05-04 14:54                             ` Oleg Nesterov
2018-05-04 15:49                               ` Eric W. Biederman
2018-05-04 16:22                                 ` Oleg Nesterov
2018-05-04 16:40                                   ` Eric W. Biederman
2018-05-04 17:26                                     ` [PATCH 0/2] mm->owner to mm->memcg fixes Eric W. Biederman
2018-05-04 17:26                                       ` [PATCH 1/2] memcg: Update the mm->memcg maintenance to work when !CONFIG_MMU Eric W. Biederman
2018-05-04 17:27                                       ` [PATCH 2/2] memcg: Close the race between migration and installing bprm->mm as mm Eric W. Biederman
2018-05-09 14:51                                         ` Oleg Nesterov
2018-05-10  3:00                                           ` Eric W. Biederman
2018-05-10 12:14                                       ` [PATCH 0/2] mm->owner to mm->memcg fixes Michal Hocko
2018-05-10 12:18                                         ` Michal Hocko
2018-05-22 12:57                                         ` Michal Hocko
2018-05-23 19:46                                           ` Eric W. Biederman
2018-05-24 11:10                                             ` Michal Hocko
2018-05-24 21:16                                               ` Andrew Morton
2018-05-24 23:37                                                 ` Andrea Parri
2018-05-30 12:17                                                 ` Michal Hocko
2018-05-31 18:41                                                   ` Eric W. Biederman
2018-06-01  1:57                                                     ` [PATCH] memcg: Replace mm->owner with mm->memcg Eric W. Biederman
2018-06-01 14:52                                                       ` [RFC][PATCH 0/2] memcg: Require every task that uses an mm to migrate together Eric W. Biederman
2018-06-01 14:53                                                         ` [RFC][PATCH 1/2] memcg: Ensure every task that uses an mm is in the same memory cgroup Eric W. Biederman
2018-06-01 16:50                                                           ` Tejun Heo
2018-06-01 18:11                                                             ` Eric W. Biederman [this message]
2018-06-01 19:16                                                               ` Tejun Heo
2018-06-04 13:01                                                                 ` Michal Hocko
2018-06-04 18:47                                                                   ` Tejun Heo
2018-06-04 19:11                                                                     ` Eric W. Biederman
2018-06-06 11:13                                                           ` Michal Hocko
2018-06-07 11:42                                                             ` Eric W. Biederman
2018-06-07 12:19                                                               ` Michal Hocko
2018-06-01 14:53                                                         ` [RFC][PATCH 2/2] memcgl: Remove dead code now that all tasks of an mm share a memcg Eric W. Biederman
2018-06-01 14:07                                                     ` [PATCH 0/2] mm->owner to mm->memcg fixes Michal Hocko
2018-05-24 21:17                                               ` Andrew Morton
2018-05-30 11:52                                             ` Michal Hocko
2018-05-31 17:43                                               ` Eric W. Biederman
2018-05-07 14:33                                     ` [PATCH] memcg: Replace mm->owner with mm->memcg Oleg Nesterov
2018-05-08  3:15                                       ` Eric W. Biederman
2018-05-09 14:40                                         ` Oleg Nesterov
2018-05-10  3:09                                           ` Eric W. Biederman
2018-05-10  4:03                                             ` [RFC][PATCH] cgroup: Don't mess with tasks in exec Eric W. Biederman
2018-05-10 12:15                                               ` Oleg Nesterov
2018-05-10 12:35                                                 ` Tejun Heo
2018-05-10 12:38                                             ` [PATCH] memcg: Replace mm->owner with mm->memcg Oleg Nesterov
2018-05-04 11:07                     ` Michal Hocko
2018-05-05 16:54                     ` kbuild test robot
2018-05-07 23:18                       ` Andrew Morton
2018-05-08  2:17                         ` Eric W. Biederman
2018-05-09 21:00                         ` Michal Hocko
2018-05-02 23:59               ` [RFC][PATCH] " Balbir Singh
2018-05-03 15:11                 ` Eric W. Biederman
2018-05-04  4:59                   ` Balbir Singh
2018-05-03 10:52           ` [PATCH 0/4] exit: Make unlikely case in mm_update_next_owner() more scalable Kirill Tkhai
2018-06-01  1:07   ` Eric W. Biederman
2018-06-01 13:57     ` Michal Hocko
2018-06-01 14:32       ` Eric W. Biederman
2018-06-01 15:02         ` Michal Hocko
2018-06-01 15:25           ` Eric W. Biederman
2018-06-04  6:54             ` Michal Hocko
2018-06-04 14:31               ` Eric W. Biederman
2018-06-05  8:15                 ` Michal Hocko
2018-06-05  8:48             ` Kirill Tkhai
2018-06-05 15:36               ` Eric W. Biederman

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=87bmcuv0k0.fsf@xmission.com \
    --to=ebiederm@xmission.com \
    --cc=akpm@linux-foundation.org \
    --cc=balbir@linux.vnet.ibm.com \
    --cc=dhowells@redhat.com \
    --cc=gs051095@gmail.com \
    --cc=hannes@cmpxchg.org \
    --cc=hoeun.ryu@gmail.com \
    --cc=keescook@chromium.org \
    --cc=kirill.shutemov@linux.intel.com \
    --cc=ktkhai@virtuozzo.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=marcos.souza.org@gmail.com \
    --cc=mhocko@kernel.org \
    --cc=mingo@kernel.org \
    --cc=oleg@redhat.com \
    --cc=pasha.tatashin@oracle.com \
    --cc=paulmck@linux.vnet.ibm.com \
    --cc=peterz@infradead.org \
    --cc=riel@redhat.com \
    --cc=rppt@linux.vnet.ibm.com \
    --cc=tglx@linutronix.de \
    --cc=tj@kernel.org \
    --cc=viro@zeniv.linux.org.uk \
    /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
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.