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 X-Spam-Level: X-Spam-Status: No, score=-2.5 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS, URIBL_BLOCKED,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E84ECC282C4 for ; Mon, 4 Feb 2019 20:26:16 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id AACBB2175B for ; Mon, 4 Feb 2019 20:26:16 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="IHRY0WCA" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org AACBB2175B Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=atomide.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject: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=vfeaIuQyr606Qe/s8larIxFoUvz/Xieci+TFHfNqlxo=; b=IHRY0WCAeT+4Gc Hzaya/x+4cWI43nkiS2300iX/VMuwh+tSeHUSByF3bdY82oRYU38Q/8enp2ialrqTktp09uLKGh0w 5J6bizXu25AeHWZ8dc7EfCVNUWQwdyDD7E18HWMOKQHtL/PFiDvQ9kNNMGw5O+o2U/gACltW12gWZ ynXOL9F5ZxPRBCqrqHP00h3IZlGLf3WfAogQsNAzD+wx9hbg0AvWIam6Rf+4z9qSKzLBB4i3AwSMl mp3v/zotBCdTd/t73HkSdU0Io1fiBh8TKjfgoHmb5sn9MdK4jxsiFqeYIBZZYn+dk4kmjZHNtk6D+ WHv1YN98BUKNVWlZqfPQ==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1gqkop-0004VA-FB; Mon, 04 Feb 2019 20:26:15 +0000 Received: from muru.com ([72.249.23.125]) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1gqkol-0004UG-Qg for linux-arm-kernel@lists.infradead.org; Mon, 04 Feb 2019 20:26:13 +0000 Received: from atomide.com (localhost [127.0.0.1]) by muru.com (Postfix) with ESMTPS id C6214808C; Mon, 4 Feb 2019 20:26:16 +0000 (UTC) Date: Mon, 4 Feb 2019 12:26:04 -0800 From: Tony Lindgren To: Lukasz Luba Subject: Re: [PATCH] config: arm: omap2: remove PROVE_LOCKING from defconfig Message-ID: <20190204202604.GP5720@atomide.com> References: <20181009153624eucas1p2ad30aea33ad1c869f11bd9ca1156d9af~b_rxQW8J90311703117eucas1p2U@eucas1p2.samsung.com> <20181108165958.GK56134@atomide.com> <21ce2c61-0b20-41f2-4d12-3c5b1c4b7925@partner.samsung.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <21ce2c61-0b20-41f2-4d12-3c5b1c4b7925@partner.samsung.com> User-Agent: Mutt/1.11.2 (2019-01-07) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190204_122611_904348_6E479581 X-CRM114-Status: GOOD ( 15.10 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-omap@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, b.zolnierkie@samsung.com Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org * Lukasz Luba [181113 10:22]: > Hi Tony, > > On 11/8/18 5:59 PM, Tony Lindgren wrote: > > Hi, > > > > * Lukasz Luba [181009 08:36]: > >> PROVE_LOCKING enables LOCKDEP, which causes big overhead on cache and > >> bus transactions. > >> > >> On some ARM big.LITTLE architecutres (Exynos 5433) the overhead is really big. > >> The overhead can be measures using hackbench which will speed up > >> by x3 times (11sec -> 3.4sec). > >> When you check transaction on cache or buses, the results are way higher > >> than normal for the same hackbench test: > >> L1d cache invalidations: 26mln vs 4mln > >> L2u cache invalidations: 42mln vs 12mln > >> bus cyc/access: 30cyc/access vs. 20cyc/access > >> context switch is x3 times cheaper > >> > >> Enable this option only when you have some locking issue to investigate. > > > > I'm all for this, but this disables also other less intrusive > > debug options. It used to be that we'd get locking issues merged > > into drivers and I think that's how it originally got enabled. > That's common reason for a few defconfigs in mainline. Actually looks like this does not change the DEBUG related options.. I must have done something wrong earlier, sorry. So applying into omap-for-v5.1/defconfig. > > So we should take a look which ones we can or want to keep. > > Or just disable CONFIG_DEBUG completely. > Ideally, the CI should try a few 'types' of configs, > generated based on the 'defconfig'. Some 'smart' script might > cut the debug options for an image for performance regression tests. > > > > For distros, that's multi_v7_defconfig nowadays for most part > > so I think most people using omap2plus_defconfig are developers > > working on various devices. Yes I think that's the case. Regards, Tony _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel