Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261392AbVAaWEa (ORCPT ); Mon, 31 Jan 2005 17:04:30 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261394AbVAaWEa (ORCPT ); Mon, 31 Jan 2005 17:04:30 -0500 Received: from alog0059.analogic.com ([208.224.220.74]:4992 "EHLO chaos.analogic.com") by vger.kernel.org with ESMTP id S261392AbVAaWEN (ORCPT ); Mon, 31 Jan 2005 17:04:13 -0500 Date: Mon, 31 Jan 2005 17:04:20 -0500 (EST) From: linux-os Reply-To: linux-os@analogic.com To: Tim Schmielau cc: lkml Subject: Re: [RFC] "biological parent" pid In-Reply-To: Message-ID: References: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3637 Lines: 92 On Mon, 31 Jan 2005, Tim Schmielau wrote: > The ppid of a process is not really helpful if I want to reconstruct the > real history of processes on a machine, since it may become 1 when the > parent dies and the process is reparented to init. > > I am not aware of concepts in Linux or other unices that apply to this > case. So I made up the "biological parent pid" bioppid (in contrast to the > adoptive parents pid) that just never changes. > Any user of it must of course remember that it doesn't need to be a valid > pid anymore or might even belong to a different process that was forked in > the meantime. bioppid only had to be a valid pid at time btime (it's > a (btime, pid) pair that unambiguously identifies a process). > > Comments? (other that I just broke /proc/nnn/status parsing once again :-) > > Tim It's worthless for the reasons cited plus others and it just adds more unused stuff to the kernel. > > > --- linux-2.6.10/include/linux/sched.h 2004-12-24 22:33:59.000000000 +0100 > +++ linux-2.6.10-ppid/include/linux/sched.h 2005-01-31 19:20:00.000000000 +0100 > @@ -556,6 +556,7 @@ struct task_struct { > unsigned did_exec:1; > pid_t pid; > pid_t tgid; > + pid_t bioppid; /* biological parents */ > /* > * pointers to (original) parent process, youngest child, younger sibling, > * older sibling, respectively. (p->father can be replaced with > > --- linux-2.6.10/kernel/fork.c 2004-12-24 22:33:59.000000000 +0100 > +++ linux-2.6.10-ppid/kernel/fork.c 2005-01-31 18:15:39.000000000 +0100 > @@ -889,6 +889,7 @@ static task_t *copy_process(unsigned lon > p->tgid = p->pid; > if (clone_flags & CLONE_THREAD) > p->tgid = current->tgid; > + p->bioppid = current->pid; > > if ((retval = security_task_alloc(p))) > goto bad_fork_cleanup_policy; > > --- linux-2.6.10/fs/proc/array.c 2004-12-24 22:35:00.000000000 +0100 > +++ linux-2.6.10-ppid/fs/proc/array.c 2005-01-31 18:19:02.000000000 +0100 > @@ -165,6 +165,7 @@ static inline char * task_state(struct t > "Tgid:\t%d\n" > "Pid:\t%d\n" > "PPid:\t%d\n" > + "BioPPid:\t%d\n" > "TracerPid:\t%d\n" > "Uid:\t%d\t%d\t%d\t%d\n" > "Gid:\t%d\t%d\t%d\t%d\n", > @@ -172,6 +173,7 @@ static inline char * task_state(struct t > (p->sleep_avg/1024)*100/(1020000000/1024), > p->tgid, > p->pid, pid_alive(p) ? p->group_leader->real_parent->tgid : 0, > + p->bioppid, > pid_alive(p) && p->ptrace ? p->parent->pid : 0, > p->uid, p->euid, p->suid, p->fsuid, > p->gid, p->egid, p->sgid, p->fsgid); > > --- linux-2.6.10/kernel/acct.c 2004-12-24 22:34:58.000000000 +0100 > +++ linux-2.6.10-ppid/kernel/acct.c 2005-01-31 18:19:35.000000000 +0100 > @@ -446,7 +446,7 @@ static void do_acct_process(long exitcod > #endif > #if ACCT_VERSION==3 > ac.ac_pid = current->tgid; > - ac.ac_ppid = current->parent->tgid; > + ac.ac_ppid = current->bioppid; > #endif > > read_lock(&tasklist_lock); /* pin current->signal */ > - > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ > Cheers, Dick Johnson Penguin : Linux version 2.6.9 on an i686 machine (5537.79 BogoMips). Notice : All mail here is now cached for review by Dictator Bush. 98.36% of all statistics are fiction. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/