Re: [PATCH 03/14] net: tcp_memcontrol: properly detect ancestor socket pressure
On Sat, Nov 14, 2015 at 03:45:52PM +0300, Vladimir Davydov wrote:
> On Thu, Nov 12, 2015 at 06:41:22PM -0500, Johannes Weiner wrote:
> > When charging socket memory, the code currently checks only the local
> > page counter for excess to determine whether the memcg is under socket
> > pressure. But even if the local counter is fine, one of the ancestors
> > could have breached its limit, which should also force this child to
> > enter socket pressure. This currently doesn't happen.
> >
> > Fix this by using page_counter_try_charge() first. If that fails, it
> > means that either the local counter or one of the ancestors are in
> > excess of their limit, and the child should enter socket pressure.
> >
> > Signed-off-by: Johannes Weiner
>
> Reviewed-by: Vladimir Davydov
Thanks Vladimir!
> For the record: it was broken by commit 3e32cb2e0a12 ("mm: memcontrol:
> lockless page counters").
I didn't realize that.
Fixes: 3e32cb2e0a12 ("mm: memcontrol: lockless page counters")
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Re: [PATCH 03/14] net: tcp_memcontrol: properly detect ancestor socket pressure
On Thu, Nov 12, 2015 at 06:41:22PM -0500, Johannes Weiner wrote:
> When charging socket memory, the code currently checks only the local
> page counter for excess to determine whether the memcg is under socket
> pressure. But even if the local counter is fine, one of the ancestors
> could have breached its limit, which should also force this child to
> enter socket pressure. This currently doesn't happen.
>
> Fix this by using page_counter_try_charge() first. If that fails, it
> means that either the local counter or one of the ancestors are in
> excess of their limit, and the child should enter socket pressure.
>
> Signed-off-by: Johannes Weiner
Reviewed-by: Vladimir Davydov
For the record: it was broken by commit 3e32cb2e0a12 ("mm: memcontrol:
lockless page counters").
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Re: [PATCH 03/14] net: tcp_memcontrol: properly detect ancestor socket pressure
From: Johannes Weiner Date: Thu, 12 Nov 2015 18:41:22 -0500 > When charging socket memory, the code currently checks only the local > page counter for excess to determine whether the memcg is under socket > pressure. But even if the local counter is fine, one of the ancestors > could have breached its limit, which should also force this child to > enter socket pressure. This currently doesn't happen. > > Fix this by using page_counter_try_charge() first. If that fails, it > means that either the local counter or one of the ancestors are in > excess of their limit, and the child should enter socket pressure. > > Signed-off-by: Johannes Weiner Acked-by: David S. Miller -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
