Re: [rfc][patch] Avoid taking global tasklist_lock for single threadedprocess at getrusage()

[Ravikiran G Thirumalai]

On Wed, Dec 28, 2005 at 03:38:39PM +0300, Oleg Nesterov wrote:
> Christoph Lameter wrote:
> > 
> > On Sat, 24 Dec 2005, Oleg Nesterov wrote:
> > 
> > > I can't understand this. 'p' can do clone(CLONE_THREAD) immediately
> > > after 'if (!thread_group_empty(p))' check.
> > 
> > Only if p != current. As discussed later the lockless approach is
> > intened to only be used if p == current.
> 
> Unless I missed something this function (getrusage_both) is called
> from wait_noreap_copyout,

Hi Oleg,
Yes, this patch needs to be reworked.  I am on it.  I'd also missed that
p->signal was protected by the tasklist_lock.  Thanks for pointing it out.
I will put out the modified version soon.

Thanks,
Kiran
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