linux-kernel - Re: Per container statistics (containerstats)

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20070607193917.c21f9071.akpm@linux-foundation.org>
Date:	Thu, 7 Jun 2007 19:39:17 -0700
From:	Andrew Morton <akpm@...ux-foundation.org>
To:	balbir@...ux.vnet.ibm.com
Cc:	menage@...gle.com, dev@...ru, xemul@...ru, serue@...ibm.com,
	vatsa@...ibm.com, ebiederm@...ssion.com, haveblue@...ibm.com,
	svaidy@...ux.vnet.ibm.com, balbir@...ibm.com, pj@....com,
	cpw@....com, ckrm-tech@...ts.sourceforge.net,
	linux-kernel@...r.kernel.org, containers@...ts.osdl.org,
	mbligh@...gle.com, rohitseth@...gle.com, devel@...nvz.org
Subject: Re: Per container statistics (containerstats)

On Fri, 08 Jun 2007 07:51:12 +0530 Balbir Singh <balbir@...ux.vnet.ibm.com> wrote:

> Andrew Morton wrote:
> > 
> > I'd have hoped to see containerstats.c in here.
> > 
> 
> The current statistics code is really small, so it fit into taskstats.c.
> May be in the future, we could re-factor it and move it out.

I was referring to your userspace tool which reads this stuff.  The one
which you described in the changelog.

> >> +	rcu_read_lock();
> >> +
> >> +	for_each_root(root) {
> >> +		if (!root->subsys_bits)
> >> +			continue;
> >> +		root_cont = &root->top_container;
> >> +		get_first_subsys(root_cont, NULL, &subsys_id);
> >> +		do_each_thread(g, p) {
> > 
> > this needs tasklist_lock?
> > 
> 
> rcu_read_lock() should be fine. From Eric's patch at
> 
> 2.6.17-mm2 - proc-remove-tasklist_lock-from-proc_pid_readdir.patch
> 
> The patch mentions that "We don't need the tasklist_lock to safely
> iterate through processes anymore."
> 

oh, OK.  rcu_read_lock() is the new lock_kernel() - always hard to tell
what it's locking.

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/