Received: by 2002:ac0:a5a7:0:0:0:0:0 with SMTP id m36-v6csp5428903imm; Tue, 31 Jul 2018 10:43:11 -0700 (PDT) X-Google-Smtp-Source: AAOMgpdWEPvMvfzOzZNG8Wilmw70s27p9HtgLRG5M8trF4J9Dl5CC1sQaO8b/RoD0gryeTfqkId9 X-Received: by 2002:a62:ce0b:: with SMTP id y11-v6mr23432371pfg.95.1533058991620; Tue, 31 Jul 2018 10:43:11 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1533058991; cv=none; d=google.com; s=arc-20160816; b=XLdGGyFAX2UlLk5UXPad/I4ttBcmzxlBf3bdNW4klremk5CWyVULHwAaBzTFoIRipF xmVdOokyki8DRXJhvzlzgEBO3wcrTIjEGgDC915Mx6xY/a6Kqd6JTHoeJmN0s3CUfki7 GJlpH2JmSueps9kZNJNiarwgSd7KUlD3OhQ0lBR3tE3eOGeNDcdgxgk1CQGHLA8zw1Lg en1GW2VszzY1XSAAli29pwK28k35Y07V47Xtz8exFGTHJ6iga713YnMxup3zsbM5yXdq uAoRpWq/7c6iYozT31l1P/ImwAQ2n+caf0J4aBlqftlqF5Zlejf7LI5YuveUD2opmxne P4Jg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:dkim-signature :arc-authentication-results; bh=dZPiLSVij48Ml7RyMFdOOkoCd/1f7/lix5KTpWVZDok=; b=W+oc9a3sjpGnSoDRTKNSCtFkditXrf+/Xdtu0Yv8Gi2JPswlJ2CfHlQFaB9uw+kzd+ XBj0cOBPrZQJ6Aazd5IiTT4fOZexsA1wcnboiAPSbSg3Zq9ogp5dHsTgVQPXn7xM6q7D 3wQKMfbam4I8y68FfV5foCIVFLjEGNPr5vOumlW5BsqxW2acYghd4/waqdBjLBzWNw55 JvaQ6wkbcarg71FWbYqyBVcPyadB1QArRpxJ1R9igIc81kN3oaZ1VY9PGNyNv4jM0N9u ZTlJbG5qmxVA7uAO/+9mcVRL7frIDVAt3zBoFlkhmjQNxhTz7PW5w6MBCQAGFi8ibVx7 n2Xw== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@google.com header.s=20161025 header.b=YKclMVW5; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=REJECT sp=REJECT dis=NONE) header.from=google.com Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id d5-v6si12301653pgq.316.2018.07.31.10.42.55; Tue, 31 Jul 2018 10:43:11 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; dkim=pass header.i=@google.com header.s=20161025 header.b=YKclMVW5; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=REJECT sp=REJECT dis=NONE) header.from=google.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730848AbeGaTX3 (ORCPT + 99 others); Tue, 31 Jul 2018 15:23:29 -0400 Received: from mail-io0-f196.google.com ([209.85.223.196]:43560 "EHLO mail-io0-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729634AbeGaTX3 (ORCPT ); Tue, 31 Jul 2018 15:23:29 -0400 Received: by mail-io0-f196.google.com with SMTP id y10-v6so13732706ioa.10 for ; Tue, 31 Jul 2018 10:42:06 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=dZPiLSVij48Ml7RyMFdOOkoCd/1f7/lix5KTpWVZDok=; b=YKclMVW54MIH2TrUVfJUGUOKzcLzesXUTCHwt6/wl+qTNoR4eOj+j0zfkMIjX42iEk m9zhb1l3yKW08YXn6kJnYsFzL0vcSDyK/+YSmYQ2KyepPQxglVzdYc7qvjv8gwyWkCtR shdXLVVrycSvOZBGEf/cYcrGVkGoTQPTF4JnvLFb6y05xSoDrQv7bRYiN7vI/TdSWD+u AhwE5hKo+k9NxJhlDfybxjEKsjviA4pNL075f5wFi+JTUuip6oMMUt2wukGrnidLjSDt IKI8STY2PZRBfZUgKzxRCAHrfVVnDAEAxuOZ2ohIRfuzFcDy2cePi/qs5w1HJ5qXlAlF pIgw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=dZPiLSVij48Ml7RyMFdOOkoCd/1f7/lix5KTpWVZDok=; b=Y+1BXT84VrNKC5JbuJrbjrOrUoztjgwl8dV9ytbBPyxhgJcoowHn7I6KbkQtr2tVeS Zu6tL1fEZj86DIDCMDivP2Ji9alN3zWeH/Kiehmm1un5syykE4UQR7VMGj0FncwMyv/Y b9IkmifECMuY5XG//lcw5eq4Ann0XYTk56KMJ/kMIUcpC3zYMBQuSyBMgFgA1sDOM3Dt W19TIwubMDuChdO30CRAJnpTkNfI/3lGkwIQjZHeEmEKl3s78BGCxJ62QiZnuCozP/U4 XxGaNaoQY5dx4OZ0arHdJkNvjYKzsr5cQ+CKwDDh6xY9NAI7uJySVI0zG1ao/KjjEl7G Aptg== X-Gm-Message-State: AOUpUlFcM4X+TJotv24EWFtUOz26a8B99dO1OqvQbIoI50xLuILiAh5n M4X3bknV+kkA8R3dt3fYE+BecYgzQAqmKXFfq951IQ== X-Received: by 2002:a6b:f10f:: with SMTP id e15-v6mr532662iog.271.1533058925770; Tue, 31 Jul 2018 10:42:05 -0700 (PDT) MIME-Version: 1.0 References: <01000164f169bc6b-c73a8353-d7d9-47ec-a782-90aadcb86bfb-000000@email.amazonses.com> In-Reply-To: <01000164f169bc6b-c73a8353-d7d9-47ec-a782-90aadcb86bfb-000000@email.amazonses.com> From: Eric Dumazet Date: Tue, 31 Jul 2018 10:41:54 -0700 Message-ID: Subject: Re: SLAB_TYPESAFE_BY_RCU without constructors (was Re: [PATCH v4 13/17] khwasan: add hooks implementation) To: Christoph Lameter Cc: Andrey Ryabinin , "Theodore Ts'o" , jack@suse.com, linux-ext4@vger.kernel.org, Greg Kroah-Hartman , Pablo Neira Ayuso , Jozsef Kadlecsik , Florian Westphal , David Miller , netfilter-devel@vger.kernel.org, coreteam@netfilter.org, netdev , Gerrit Renker , 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 , Hideaki YOSHIFUJI , Ursula Braun , linux-s390@vger.kernel.org, LKML , Dmitry Vyukov , Andrew Morton , linux-mm , Andrey Konovalov , Linus Torvalds Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jul 31, 2018 at 10:36 AM Christopher Lameter wrote: > > If there is refcounting going on then why use SLAB_TYPESAFE_BY_RCU? To allow fast reuse of objects, without going through call_rcu() and reducing cache efficiency. I believe this is mentioned in Documentation/RCU/rculist_nulls.txt