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[54.240.9.33]) by mx.google.com with ESMTPS id h3si1216026qtr.376.2019.04.18.06.34.53 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Thu, 18 Apr 2019 06:34:53 -0700 (PDT) Received-SPF: pass (google.com: domain of 0100016a30a83bcf-7f99039c-77ec-4c48-a1c4-92e398f8f185-000000@amazonses.com designates 54.240.9.33 as permitted sender) client-ip=54.240.9.33; Authentication-Results: mx.google.com; dkim=pass header.i=@amazonses.com header.s=6gbrjpgwjskckoa6a5zn6fwqkn67xbtw header.b=ab1gt2ub; spf=pass (google.com: domain of 0100016a30a83bcf-7f99039c-77ec-4c48-a1c4-92e398f8f185-000000@amazonses.com designates 54.240.9.33 as permitted sender) smtp.mailfrom=0100016a30a83bcf-7f99039c-77ec-4c48-a1c4-92e398f8f185-000000@amazonses.com DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/simple; s=6gbrjpgwjskckoa6a5zn6fwqkn67xbtw; d=amazonses.com; t=1555594493; h=Date:From:To:cc:Subject:In-Reply-To:Message-ID:References:MIME-Version:Content-Type:Feedback-ID; bh=tGKbg7T4m2hja67VSnD+5sN45YQjy0gEHiOhoXRYwnE=; b=ab1gt2ubDBnvlERvCSi1ce9rbtCoG/YS77M3OGWWcVMUjDZG7kdCTAIh3pFVU73u JBYkidNGYMpwtlzEcOGCrYV7+GGxIkApxsJL4FIYB0Sro4vm00cQ7klrHZkK5gkWFTd +5z2ftsGtTwkIdbIkR74gay/PBi7mTjrZi0orids= Date: Thu, 18 Apr 2019 13:34:52 +0000 From: Christopher Lameter X-X-Sender: cl@nuc-kabylake To: Roman Gushchin cc: Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org, kernel-team@fb.com, Johannes Weiner , Michal Hocko , Rik van Riel , david@fromorbit.com, Pekka Enberg , Vladimir Davydov , cgroups@vger.kernel.org, Roman Gushchin Subject: Re: [PATCH 4/5] mm: rework non-root kmem_cache lifecycle management In-Reply-To: <20190417215434.25897-5-guro@fb.com> Message-ID: <0100016a30a83bcf-7f99039c-77ec-4c48-a1c4-92e398f8f185-000000@email.amazonses.com> References: <20190417215434.25897-1-guro@fb.com> <20190417215434.25897-5-guro@fb.com> User-Agent: Alpine 2.21 (DEB 202 2017-01-01) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII X-SES-Outgoing: 2019.04.18-54.240.9.33 Feedback-ID: 1.us-east-1.fQZZZ0Xtj2+TD7V5apTT/NrT6QKuPgzCT/IC7XYgDKI=:AmazonSES X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Wed, 17 Apr 2019, Roman Gushchin wrote: > Let's make every page to hold a reference to the kmem_cache (we > already have a stable pointer), and make kmem_caches to hold a single > reference to the memory cgroup. Ok you are freeing one word in the page struct that can be used for other purposes now?