From: Oleg Nesterov <oleg@redhat.com>
To: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Pavel Emelyanov <xemul@parallels.com>, Tejun Heo <tj@kernel.org>,
Pedro Alves <pedro@codesourcery.com>,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
Cyrill Gorcunov <gorcunov@openvz.org>,
James Bottomley <jbottomley@parallels.com>
Subject: Re: [RFC][PATCH 0/3] fork: Add the ability to create tasks with given pids
Date: Sun, 27 Nov 2011 18:34:30 +0100 [thread overview]
Message-ID: <20111127173430.GB5674@redhat.com> (raw)
In-Reply-To: <4ED205D1.5060407@openvz.org>
On 11/27, Konstantin Khlebnikov wrote:
>
> We can add flag to sys_wait4(), and stash pid in wait_task_zombie(), right before release_task()
> code will looks something like this:
>
> - if (p != NULL)
> + if (p != NULL) {
> + if ((wo->wo_flags & WCATCHPID) && !current->pid_stash) {
> + struct pid *pid = task_pid(p);
> +
> + pid->flags |= PID_STASHED;
> + current->pid_stash = get_pid(pid);
> + }
> release_task(p);
> + }
>
> And next fork() creates child with the same pid.
> So, struct pid will work like boomerang =)
Like PR_RESERVE_PID, this can only help if the tracee (or whatever)
is single-threaded and it is the natural child.
Personally I do not think such a limited interface makes sense.
Oleg.
next prev parent reply other threads:[~2011-11-27 17:39 UTC|newest]
Thread overview: 46+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-11-17 11:41 [RFC][PATCH 0/3] fork: Add the ability to create tasks with given pids Pavel Emelyanov
2011-11-17 11:42 ` [PATCH 1/3] pids: Make alloc_pid return error Pavel Emelyanov
2011-11-17 11:42 ` [PATCH 2/3] pids: Split alloc_pidmap into parts Pavel Emelyanov
2011-11-17 11:43 ` [PATCH 3/3] pids: Make it possible to clone tasks with given pids Pavel Emelyanov
2011-11-17 15:32 ` Oleg Nesterov
2011-11-17 15:49 ` Pavel Emelyanov
2011-11-17 16:00 ` Oleg Nesterov
2011-11-17 17:28 ` Linus Torvalds
2011-11-17 19:04 ` Oleg Nesterov
2011-11-17 18:36 ` Oleg Nesterov
2011-11-18 10:05 ` Pavel Emelyanov
2011-11-17 15:49 ` [RFC][PATCH 0/3] fork: Add the ability to create " Oleg Nesterov
2011-11-17 16:01 ` Pavel Emelyanov
2011-11-17 16:02 ` Oleg Nesterov
2011-11-18 23:30 ` Tejun Heo
2011-11-21 9:15 ` Pavel Emelyanov
2011-11-21 22:50 ` Tejun Heo
2011-11-22 11:11 ` Pavel Emelyanov
2011-11-22 12:04 ` Pedro Alves
2011-11-22 15:33 ` Tejun Heo
2011-11-23 16:20 ` Pedro Alves
2011-11-23 16:24 ` Tejun Heo
2011-11-23 17:26 ` Oleg Nesterov
2011-11-23 17:37 ` Tejun Heo
2011-11-23 18:19 ` Pavel Emelyanov
2011-11-23 20:14 ` Pavel Emelyanov
2011-11-24 17:31 ` Oleg Nesterov
2011-11-25 10:14 ` Pavel Emelyanov
2011-11-25 16:22 ` Oleg Nesterov
2011-11-25 16:44 ` Pavel Emelyanov
2011-11-25 16:54 ` Oleg Nesterov
2011-11-25 17:03 ` Pavel Emelyanov
2011-11-25 22:36 ` Pedro Alves
2011-11-27 16:24 ` [RFC][PATCH 0/3] fork: Add the ability to create tasks with?given pids Oleg Nesterov
2011-11-27 9:41 ` [RFC][PATCH 0/3] fork: Add the ability to create tasks with given pids Konstantin Khlebnikov
2011-11-27 17:34 ` Oleg Nesterov [this message]
2011-11-27 18:47 ` Tejun Heo
2011-11-28 10:38 ` Pavel Emelyanov
2011-11-28 16:25 ` Tejun Heo
2011-11-22 15:23 ` Tejun Heo
2011-11-22 15:29 ` Tejun Heo
2011-11-22 16:30 ` Pavel Emelyanov
2011-11-22 16:44 ` Linus Torvalds
2011-11-22 19:29 ` Pavel Emelyanov
2012-01-26 23:28 ` Kay Sievers
2011-11-22 21:16 ` Oleg Nesterov
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