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=-5.8 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 D3807C4338F for ; Tue, 17 Aug 2021 09:34:12 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 6955160FD8 for ; Tue, 17 Aug 2021 09:34:12 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 6955160FD8 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linutronix.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvack.org Received: by kanga.kvack.org (Postfix) id 1022C8D0003; Tue, 17 Aug 2021 05:34:12 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 08BA78D0001; Tue, 17 Aug 2021 05:34:12 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id E6EFB8D0003; Tue, 17 Aug 2021 05:34:11 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0077.hostedemail.com [216.40.44.77]) by kanga.kvack.org (Postfix) with ESMTP id C9FA98D0001 for ; Tue, 17 Aug 2021 05:34:11 -0400 (EDT) Received: from smtpin13.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 658C5181D130B for ; Tue, 17 Aug 2021 09:34:11 +0000 (UTC) X-FDA: 78484061502.13.5A485E6 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) by imf15.hostedemail.com (Postfix) with ESMTP id 04B45D007C27 for ; Tue, 17 Aug 2021 09:34:10 +0000 (UTC) Date: Tue, 17 Aug 2021 11:34:08 +0200 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1629192849; 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=IZ6fACXUc9apVwlz8xHJ8mN1EdefFeUDadYvHeqk1X4=; b=3s8hAMQiMxa0vuIbKYwmkRIGf5kGXAurxh8BLI70WIR9mypWnYmZkIB/13g+wBQDJbJLmH PQyQF5ETYv+GrOHioyMtiadHUKVFELfNY0HCkz1GKFpQXWBb6a2BHiMzAXun2SJyCSwZ+n uA+jbQ+TpfovebZqJfOQ4qyhpbBEt2rWb/HY16Jui4OhgSfGDzpTJjsuVgQKNUnY0EzjZ5 0hQflpoZYWg/be0Hue5mF19r63WQKEhh7fnkUM0GZwjpuV1ohB7IV5lVN6ps94PemKnV9i E9f5krH4zdz4jC52TfcnBiyi0Y0IwToD1rop0g2qQwuEDV99uCdaktcDB9Dtvg== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1629192849; 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=IZ6fACXUc9apVwlz8xHJ8mN1EdefFeUDadYvHeqk1X4=; b=bIGH2L88+AIsWN+iUd3kfGlZWpIcGLdQNkfOtDLmSa5eYpElsoU8Q4iTmGYdJJayifC69g vAWEvEJW849aIxCw== From: Sebastian Andrzej Siewior To: Vlastimil Babka Cc: Sven Eckelmann , akpm@linux-foundation.org, brouer@redhat.com, cl@linux.com, efault@gmx.de, iamjoonsoo.kim@lge.com, jannh@google.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, mgorman@techsingularity.net, penberg@kernel.org, rientjes@google.com, tglx@linutronix.de, Stephen Rothwell , Peter Zijlstra Subject: Re: [PATCH v4 35/35] mm, slub: convert kmem_cpu_slab protection to local_lock Message-ID: <20210817093408.zanfoybsbnrdnav7@linutronix.de> References: <2666777.vCjUEy5FO1@sven-desktop> <7329198a-2a4e-ebc2-abf8-f7f38f00d5e1@suse.cz> <20210817091224.nqnrro34cyb67chj@linutronix.de> <3da13f0a-2720-a38c-33a7-744668013390@suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <3da13f0a-2720-a38c-33a7-744668013390@suse.cz> Authentication-Results: imf15.hostedemail.com; dkim=pass header.d=linutronix.de header.s=2020 header.b=3s8hAMQi; dkim=pass header.d=linutronix.de header.s=2020e header.b=bIGH2L88; spf=pass (imf15.hostedemail.com: domain of bigeasy@linutronix.de designates 193.142.43.55 as permitted sender) smtp.mailfrom=bigeasy@linutronix.de; dmarc=pass (policy=none) header.from=linutronix.de X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: 04B45D007C27 X-Stat-Signature: zaja59ckemc7cjuzn3g4yggqfrj34bgt X-HE-Tag: 1629192850-603512 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On 2021-08-17 11:31:56 [+0200], Vlastimil Babka wrote: > On 8/17/21 11:12 AM, Sebastian Andrzej Siewior wrote: > > On 2021-08-17 10:37:48 [+0200], Vlastimil Babka wrote: > >> OK reproduced. Thanks, will investigate. > > > > With the local_lock at the top, the needed alignment gets broken for dbl > > cmpxchg. > > Right. I wondered why the checks in __pcpu_double_call_return_bool > didn't trigger. They are VM_BUG_ON() so they did trigger after enabling > DEBUG_VM. Without the right debugging enabled | typedef struct { | #ifdef CONFIG_DEBUG_LOCK_ALLOC | struct lockdep_map dep_map; | struct task_struct *owner; | #endif | } local_lock_t; the struct is just empty. Sebastian