From: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
To: "Paul Menage" <menage@google.com>
Cc: "Andrew Morton" <akpm@linux-foundation.org>,
"Ingo Molnar" <mingo@elte.hu>,
containers@lists.linux-foundation.org,
linux-kernel@vger.kernel.org, dmitry.adamushko@gmail.com
Subject: Re: [PATCH 2/2] CFS CGroup: Report usage
Date: Tue, 23 Oct 2007 22:11:24 +0530 [thread overview]
Message-ID: <20071023164124.GA4666@linux.vnet.ibm.com> (raw)
In-Reply-To: <6599ad830710222306m6a3e3f52k4daf501836c05274@mail.gmail.com>
On Mon, Oct 22, 2007 at 11:06:54PM -0700, Paul Menage wrote:
> > > + for_each_possible_cpu(i) {
> > > + unsigned long flags;
> > > + spin_lock_irqsave(&tg->cfs_rq[i]->rq->lock, flags);
> >
> > Is the lock absolutely required here?
>
> I'm not sure, I was hoping you or Ingo could comment on this. But some
> kind of locking seems to required at least on 32-bit platforms, since
> sum_exec_runtime is a 64-bit number.
I tend to agree abt 32-bit platforms requiring a lock to read the 64-bit
sum_exec_runtime field.
Ingo/Dmitry, what do you think? fs/proc/array.c:task_utime() is also
buggy in that case.
--
Regards,
vatsa
next prev parent reply other threads:[~2007-10-23 16:29 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-10-23 0:49 [PATCH 2/2] CFS CGroup: Report usage Paul Menage
2007-10-23 2:40 ` Srivatsa Vaddagiri
2007-10-23 6:06 ` Paul Menage
2007-10-23 7:21 ` Paul Menage
2007-10-23 7:49 ` Balbir Singh
2007-10-23 7:53 ` Paul Menage
2007-10-23 7:57 ` Balbir Singh
2007-10-23 8:08 ` Paul Menage
2007-10-23 16:41 ` Srivatsa Vaddagiri [this message]
2007-10-23 3:17 ` Balbir Singh
2007-10-23 6:09 ` Paul Menage
2007-10-23 16:43 ` Srivatsa Vaddagiri
2007-10-23 16:47 ` Srivatsa Vaddagiri
2007-10-23 16:41 ` Paul Menage
2007-10-23 17:38 ` Srivatsa Vaddagiri
2007-10-24 2:28 ` Paul Menage
2007-10-24 4:39 ` Srivatsa Vaddagiri
2007-10-26 1:24 ` Paul Menage
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