Re: [PATCH v1] [mm] Set page->slab_cache for every page allocated for a kmem_cache.

From	Alexander Potapenko <glider@google.com>
Newsgroups	linux.kernel
Subject	Re: [PATCH v1] [mm] Set page->slab_cache for every page allocated for a kmem_cache.
Date	2016-05-27 19:50 +0200
Message-ID	<rDu3v-6qK-1@gated-at.bofh.it> (permalink)
References	<rDtAt-6gF-7@gated-at.bofh.it> <rDtTQ-6nl-21@gated-at.bofh.it>
Organization	linux.* mail to news gateway

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On Fri, May 27, 2016 at 7:30 PM, Christoph Lameter <cl@linux.com> wrote:
> On Fri, 27 May 2016, Alexander Potapenko wrote:
>
>> It's reasonable to rely on the fact that for every page allocated for a
>> kmem_cache the |slab_cache| field points to that cache. Without that it's
>> hard to figure out which cache does an allocated object belong to.
>
> The flags are set only in the head page of a coumpound page which is used
> by SLAB. No need to do this. This would just mean unnecessarily dirtying
> struct page cachelines on allocation.
>

Got it, thank you.
Looks like I just need to make sure my code uses
virt_to_head_page()->page_slab to get the cache for an object.

-- 
Alexander Potapenko
Software Engineer

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[PATCH v1] [mm] Set page->slab_cache for every page allocated for a kmem_cache. Alexander Potapenko <glider@google.com> - 2016-05-27 19:20 +0200
  Re: [PATCH v1] [mm] Set page->slab_cache for every page allocated  for a kmem_cache. Christoph Lameter <cl@linux.com> - 2016-05-27 19:40 +0200
    Re: [PATCH v1] [mm] Set page->slab_cache for every page allocated for  a kmem_cache. Alexander Potapenko <glider@google.com> - 2016-05-27 19:50 +0200

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