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=-4.1 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=no 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 2C6BDC433E2 for ; Fri, 4 Sep 2020 10:26:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id ECB0920791 for ; Fri, 4 Sep 2020 10:26:29 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="LWuI98ju"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="uzvNLAjC" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730151AbgIDK0Z (ORCPT ); Fri, 4 Sep 2020 06:26:25 -0400 Received: from Galois.linutronix.de ([193.142.43.55]:60380 "EHLO galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729950AbgIDK0K (ORCPT ); Fri, 4 Sep 2020 06:26:10 -0400 From: Thomas Gleixner DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1599215168; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=IIb9DxOVf2o7mz0utSYXLof9MskW68PFyAZoe+fk2Dc=; b=LWuI98juUnFZ+JFLdt+0iKBUigefi/KYCS+j6l2a5xLL9E0FL24XqIKriMo5D/ukklNXSd tpTACXWre12qyiDSXiJ6BuAKRHGfYtU4PLVNKspVcDx82G58/8rDDWjBinLPqi+TYVuQM0 6MNOetV609tkmMRdomNBJW1fWyIsB+TfBoPnJoxfpQMjHzzJEXdWvR8YM3PzoQWWeiceT7 y1oxW3Xg4xgCPZEg4ovz+zM5hRU4tclboo/Y3XVls5wepQxR3O4cI83bFrSMnc/sHA5uFb HeDd2quLlPlf7N9JWFR8Iw785/8gaQwqQL60S67ovWup6Ww9/LnNqqCuHzYQHQ== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1599215168; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=IIb9DxOVf2o7mz0utSYXLof9MskW68PFyAZoe+fk2Dc=; b=uzvNLAjCd5bnR28TEdEGvfM9tM7O+dwNUAz98ohBpBG1BITpbM40TZDR20cs9fY8XvXMMD zS+HQ2911yr3hRCg== To: Ingo Molnar , "Zhang\, Qiang" Cc: "longman\@redhat.com" , "elver\@google.com" , "linux-kernel\@vger.kernel.org" Subject: Re: =?utf-8?B?5Zue5aSNOg==?= [PATCH v2] debugobjects: install cpu hotplug callback In-Reply-To: <20200904055040.GA2765622@gmail.com> References: <20200827050614.15100-1-qiang.zhang@windriver.com> <20200904055040.GA2765622@gmail.com> Date: Fri, 04 Sep 2020 12:26:07 +0200 Message-ID: <87k0x94z40.fsf@nanos.tec.linutronix.de> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Sep 04 2020 at 07:50, Ingo Molnar wrote: >> +#if defined(CONFIG_HOTPLUG_CPU) >> +static int object_cpu_offline(unsigned int cpu) >> +{ >> + struct debug_percpu_free *percpu_pool; >> + struct hlist_node *tmp; >> + struct debug_obj *obj; >> + >> + percpu_pool = per_cpu_ptr(&percpu_obj_pool, cpu); >> + hlist_for_each_entry_safe(obj, tmp, &percpu_pool->free_objs, node) { >> + hlist_del(&obj->node); >> + kmem_cache_free(obj_cache, obj); >> + } >> + >> + return 0; >> +} >> +#endif > > What happens to ->obj_free, if the CPU is brought back online? Won't it be > out of sync at that point? Yes and it's going to do the completely wrong thing. Thanks, tglx