From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id CE342C433EF for ; Mon, 25 Apr 2022 15:57:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=XDPNic+25XGkjA8k7WvfzllWDsQ2gxRN2ZwRVphWB1U=; b=o8Q0chh6FzgQr8 C8IYPisrYN1H+OlRLFC9Nx0rLm5kFias8gYnemDnL3uc7QdMfv+8vRA95o834Rmyd50RK3tGPjHsI 508tMjdngEKIyAmoBMMjqlL2jhe6s7uA3qQLvjj9LfkkDO9dsA25MpXccTuOhvScIBuC32bH/og4x EgGehXQqzO4x7gkBYatXrab+AA7fCHHmpnTaOmXWljaYSDHkRJH5dCMMutlwE+/UM5SJOD46CXXOJ zoLq4ePPovmSe2kK3Ai6idTKfz/WECjTxfsQdYIxtgjifUSJTXyj/Ans14GjJ6uixyXwCJYFzt55y nHyl7HDNLpUeseEHukTQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nj14R-00ACEb-QW; Mon, 25 Apr 2022 15:56:15 +0000 Received: from dfw.source.kernel.org ([139.178.84.217]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1nj14O-00ACDZ-O9 for linux-arm-kernel@lists.infradead.org; Mon, 25 Apr 2022 15:56:14 +0000 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 3B91361278; Mon, 25 Apr 2022 15:56:12 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A0018C385A9; Mon, 25 Apr 2022 15:56:08 +0000 (UTC) Date: Mon, 25 Apr 2022 16:56:05 +0100 From: Catalin Marinas To: Peter Collingbourne Cc: Andrey Konovalov , Hyeonggon Yoo <42.hyeyoo@gmail.com>, Andrew Morton , Linux ARM , Linux Memory Management List , Linux Kernel Mailing List , vbabka@suse.cz, penberg@kernel.org, roman.gushchin@linux.dev, iamjoonsoo.kim@lge.com, rientjes@google.com, Herbert Xu , Andrey Ryabinin , Alexander Potapenko , Dmitry Vyukov , kasan-dev , Eric Biederman , Kees Cook Subject: Re: [PATCH v3] mm: make minimum slab alignment a runtime property Message-ID: References: <20220422201830.288018-1-pcc@google.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20220422201830.288018-1-pcc@google.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220425_085612_869191_9516C723 X-CRM114-Status: GOOD ( 15.72 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Fri, Apr 22, 2022 at 01:18:30PM -0700, Peter Collingbourne wrote: > When CONFIG_KASAN_HW_TAGS is enabled we currently increase the minimum > slab alignment to 16. This happens even if MTE is not supported in > hardware or disabled via kasan=off, which creates an unnecessary > memory overhead in those cases. Eliminate this overhead by making > the minimum slab alignment a runtime property and only aligning to > 16 if KASAN is enabled at runtime. > > On a DragonBoard 845c (non-MTE hardware) with a kernel built with > CONFIG_KASAN_HW_TAGS, waiting for quiescence after a full Android > boot I see the following Slab measurements in /proc/meminfo (median > of 3 reboots): > > Before: 169020 kB > After: 167304 kB > > Link: https://linux-review.googlesource.com/id/I752e725179b43b144153f4b6f584ceb646473ead > Signed-off-by: Peter Collingbourne > Reviewed-by: Andrey Konovalov Reviewed-by: Catalin Marinas _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel