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Subject: Re: SLAB_TYPESAFE_BY_RCU without constructors (was Re: [PATCH v4
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From: Eric Dumazet <eric.dumazet@gmail.com>
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Date: Wed, 1 Aug 2018 09:25:55 -0700
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To: Christopher Lameter <cl@linux.com>, Eric Dumazet <edumazet@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>, Eric Dumazet <eric.dumazet@gmail.com>, Andrey Ryabinin <aryabinin@virtuozzo.com>, Linus Torvalds <torvalds@linux-foundation.org>, Theodore Ts'o <tytso@mit.edu>, jack@suse.com, linux-ext4@vger.kernel.org, Greg Kroah-Hartman <gregkh@linuxfoundation.org>, Pablo Neira Ayuso <pablo@netfilter.org>, Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>, Florian Westphal <fw@strlen.de>, David Miller <davem@davemloft.net>, netfilter-devel@vger.kernel.org, coreteam@netfilter.org, netdev <netdev@vger.kernel.org>, Gerrit Renker <gerrit@erg.abdn.ac.uk>, dccp@vger.kernel.org, jani.nikula@linux.intel.com, joonas.lahtinen@linux.intel.com, rodrigo.vivi@intel.com, airlied@linux.ie, intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>, Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>, Ursula Braun <ubraun@linux.ibm.com>, linux-s390@vger.kernel.org, LKML <linux-kernel@vger.kernel.org>, Andrew Morton <akpm@linux-foundation.org>, linux-mm <linux-mm@kvack.org>, Andrey Konovalov <andreyknvl@google.com>



On 08/01/2018 09:22 AM, Christopher Lameter wrote:
> On Wed, 1 Aug 2018, Eric Dumazet wrote:
> 
>> The idea of having a ctor() would only be a win if all the fields that
>> can be initialized in the ctor are contiguous and fill an integral
>> number of cache lines.
> 
> Ok. Its reducing code size and makes the object status more consistent.
> Isn't that enough?
> 

Prove it ;)

I yet have to seen actual numbers.