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From: aruna.ramakrishna@oracle.com
Subject: Re: [PATCH v2] mm/slab: Improve performance of gathering slabinfo
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To: Christoph Lameter <cl@linux.com>, Joonsoo Kim <iamjoonsoo.kim@lge.com>
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Date: Wed, 17 Aug 2016 00:13:41 -0700
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On 08/16/2016 08:52 AM, Christoph Lameter wrote:
>
> On Tue, 16 Aug 2016, Joonsoo Kim wrote:
>
>> In SLUB, nr_slabs is manipulated without holding a lock so atomic
>> operation should be used.
>
> It could be moved under the node lock.
>

Christoph, Joonsoo,

I agree that nr_slabs could be common between SLAB and SLUB, but I think 
that should be a separate patch, since converting nr_slabs to unsigned 
long for SLUB will cause quite a bit of change in mm/slub.c that is not 
related to adding counters to SLAB.

I'll send out an updated slab counters patch with Joonsoo's suggested 
fix tomorrow (nr_slabs will be unsigned long for SLAB only, and there 
will be a separate definition for SLUB), and once that's in, I'll create 
a new patch that makes nr_slabs common for SLAB and SLUB, and also 
converts total_objects to unsigned long. Maybe it can include some more 
cleanup too. Does that sound acceptable?

Thanks,
Aruna