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=-5.1 required=3.0 tests=DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_PASS, T_DKIM_INVALID,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 4B9FCC43382 for ; Tue, 25 Sep 2018 15:33:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 03E1A2086E for ; Tue, 25 Sep 2018 15:33:12 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="aDtIEYWw" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 03E1A2086E Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729774AbeIYVlM (ORCPT ); Tue, 25 Sep 2018 17:41:12 -0400 Received: from bombadil.infradead.org ([198.137.202.133]:33136 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729438AbeIYVlL (ORCPT ); Tue, 25 Sep 2018 17:41:11 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=tvu2VJP2WyEjHnc8hzb8eViFE4xovbp59vcO8nNjWhg=; b=aDtIEYWwtv11sOvk7gzWQkVUO 13UWxvKKH60Sfz+fl4xsgqxMmXnrPbh7WJSdgq3fdhGK3/Lbo82zg6rYiJTzS+EGr+OinsddmBbj2 glv078NItHBmj0ah9vBEz2O8e3HAtqvt0YIqUldC7ARRCr/n9SHYx6UUMy5QvEwMnYPMSP3q4duc7 msbn9TxJVNvtdsc87Iz+ASR/KljwVG1XbLPdRYhPFdTH6UbsKrCCF/iHiBqqNv+kTKsVt7pQDqQBa 9axee0M/g2yD3T9aJuwbXTHJ51s8u6yJ0F0ITRdq7ojY4Tc8+5Gsz80UgelLmbOF0yAvV7VbeVHuU Cp1xc0BxQ==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=hirez.programming.kicks-ass.net) by bombadil.infradead.org with esmtpsa (Exim 4.90_1 #2 (Red Hat Linux)) id 1g4pKN-0002Lz-1Q; Tue, 25 Sep 2018 15:33:03 +0000 Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 26A8720289D10; Tue, 25 Sep 2018 17:32:41 +0200 (CEST) Date: Tue, 25 Sep 2018 17:32:41 +0200 From: Peter Zijlstra To: Waiman Long Cc: Thomas Gleixner , Ingo Molnar , Will Deacon , linux-kernel@vger.kernel.org, Yang Shi , Arnd Bergmann , chuhu@redhat.com Subject: Re: [PATCH v2 2/2] debugobjects: Disable lockdep tracking of debugobjects internal locks Message-ID: <20180925153241.GD29985@hirez.programming.kicks-ass.net> References: <1537886469-18227-1-git-send-email-longman@redhat.com> <1537886469-18227-3-git-send-email-longman@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1537886469-18227-3-git-send-email-longman@redhat.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Sep 25, 2018 at 10:41:09AM -0400, Waiman Long wrote: > diff --git a/lib/debugobjects.c b/lib/debugobjects.c > index 70935ed91125..68d72ed9ca22 100644 > --- a/lib/debugobjects.c > +++ b/lib/debugobjects.c > @@ -1106,8 +1106,15 @@ void __init debug_objects_early_init(void) > { > int i; > > - for (i = 0; i < ODEBUG_HASH_SIZE; i++) > + /* > + * We don't need lockdep to verify correctness of debugobjects > + * internal locks. > + */ > + lockdep_set_novalidate_class(&pool_lock); > + for (i = 0; i < ODEBUG_HASH_SIZE; i++) { > raw_spin_lock_init(&obj_hash[i].lock); > + lockdep_set_novalidate_class(&obj_hash[i].lock); > + } > > for (i = 0; i < ODEBUG_POOL_SIZE; i++) > hlist_add_head(&obj_static_pool[i].node, &obj_pool); NAK, we do not _EVER_ set novalidate if it can at all be avoided. If there is a severe performance problem with lockdep, try and cure that. But really, who runs lockdep kernels on 8 sockets?