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SubjectRe: [Slub allocator] There are chances that kmem_cache_cpu->freelist gets lost if the process happens to be rescheduled to a differenet cpu before the local_irq_save() completes in __slab_alloc()
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Le lundi 12 décembre 2011 à 12:53 -0600, Christoph Lameter a écrit :
> On Mon, 12 Dec 2011, Eric Dumazet wrote:
>
> > Indeed, I reproduced the leak with hackbench and lot of threads.
>
> Ran it here and did not see anything. But obviously this is an issue.
> Strange that no one noticed earlier. Usage of CONFIG_PREEMPT must not be
> that frequent.
>

Yes, probably :(

All I did was using hackbench with 4000 threads on my 16 cpu machine,

while :; do hackbench 100 process 2000 ; done

I got about one leak (freelist chain, so several objects leaked) per
second.



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