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[209.85.220.65]) by mx.google.com with SMTPS id d81sor1056637ywh.135.2019.03.11.10.14.05 for (Google Transport Security); Mon, 11 Mar 2019 10:14:05 -0700 (PDT) Received-SPF: pass (google.com: domain of hannes@cmpxchg.org designates 209.85.220.65 as permitted sender) client-ip=209.85.220.65; Authentication-Results: mx.google.com; dkim=pass header.i=@cmpxchg-org.20150623.gappssmtp.com header.s=20150623 header.b=cbnTo9uh; spf=pass (google.com: domain of hannes@cmpxchg.org designates 209.85.220.65 as permitted sender) smtp.mailfrom=hannes@cmpxchg.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=cmpxchg.org DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cmpxchg-org.20150623.gappssmtp.com; s=20150623; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=y58oEk6VFS6vSzvCUZ1rAopBEFvhw4rM0vVvFY79z3w=; b=cbnTo9uhVT9wL0/pDjHdpqDCQAmDqAAWTT5Y5z3BS8FgIRZRCmrMBSupLQtrmwiEU7 KNWY5PgO92GOlMjDPP0UOCN5cJxUoHP6F0cYtfYBH0kvGx0Df9p0KqeMeAinp7e6Hn7H qFeICoJOIUdbPnLvus51stmzJXaJ/+uInYfSGDOxkAxWBeJKtUvW2rdohxe2yz7qvTQ6 0O1D0M5XS3k4/pk8AY5EFdwCn5gOgS7J1ZsHZ45xqR571yERkeULGtH3An/Fy/czxlTE 94o1WvQc7t0r8iKPOxsSvgeCImOhz2aSP1OZVo2zCD6Jtc2HJuGJIQcB4TXESbv9wLGo hUUw== X-Google-Smtp-Source: APXvYqwbksG6pV6NHQrSLAiG/AmNqN4B0KIeTZpNK2uAn6ch6pNfdQ5TPs6pHjzKEEq0BGkEHZCHyA== X-Received: by 2002:a81:a055:: with SMTP id x82mr26386742ywg.177.1552324444748; Mon, 11 Mar 2019 10:14:04 -0700 (PDT) Received: from localhost ([2620:10d:c091:200::1:3c60]) by smtp.gmail.com with ESMTPSA id j10sm1933530ywb.39.2019.03.11.10.14.03 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Mon, 11 Mar 2019 10:14:03 -0700 (PDT) Date: Mon, 11 Mar 2019 13:14:02 -0400 From: Johannes Weiner To: Roman Gushchin Cc: linux-mm@kvack.org, kernel-team@fb.com, linux-kernel@vger.kernel.org, Tejun Heo , Rik van Riel , Michal Hocko , Roman Gushchin Subject: Re: [PATCH 1/5] mm: prepare to premature release of memcg->vmstats_percpu Message-ID: <20190311171402.GA10823@cmpxchg.org> References: <20190307230033.31975-1-guro@fb.com> <20190307230033.31975-2-guro@fb.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190307230033.31975-2-guro@fb.com> User-Agent: Mutt/1.11.3 (2019-02-01) 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 Thu, Mar 07, 2019 at 03:00:29PM -0800, Roman Gushchin wrote: > Prepare to handle premature release of memcg->vmstats_percpu data. > Currently it's a generic pointer which is expected to be non-NULL > during the whole life time of a memcg. Switch over to the > rcu-protected pointer, and carefully check it for being non-NULL. > > This change is a required step towards dynamic premature release > of percpu memcg data. > > Signed-off-by: Roman Gushchin Acked-by: Johannes Weiner