Messages in this thread | | | Date | Tue, 23 Oct 2007 22:11:24 +0530 | From | Srivatsa Vaddagiri <> | Subject | Re: [PATCH 2/2] CFS CGroup: Report usage |
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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 - 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/
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