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=-10.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 847A8C4320A for ; Thu, 29 Jul 2021 15:43:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6BB4260F21 for ; Thu, 29 Jul 2021 15:43:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237913AbhG2PnK (ORCPT ); Thu, 29 Jul 2021 11:43:10 -0400 Received: from outbound-smtp08.blacknight.com ([46.22.139.13]:47313 "EHLO outbound-smtp08.blacknight.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237909AbhG2PnI (ORCPT ); Thu, 29 Jul 2021 11:43:08 -0400 Received: from mail.blacknight.com (pemlinmail01.blacknight.ie [81.17.254.10]) by outbound-smtp08.blacknight.com (Postfix) with ESMTPS id 10A421C47F0 for ; Thu, 29 Jul 2021 16:43:04 +0100 (IST) Received: (qmail 15224 invoked from network); 29 Jul 2021 15:43:03 -0000 Received: from unknown (HELO techsingularity.net) (mgorman@techsingularity.net@[84.203.17.255]) by 81.17.254.9 with ESMTPSA (AES256-SHA encrypted, authenticated); 29 Jul 2021 15:43:03 -0000 Date: Thu, 29 Jul 2021 16:43:02 +0100 From: Mel Gorman To: Vlastimil Babka Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Christoph Lameter , David Rientjes , Pekka Enberg , Joonsoo Kim , Mike Galbraith , Sebastian Andrzej Siewior , Thomas Gleixner , Jesper Dangaard Brouer , Jann Horn Subject: Re: [PATCH v3 31/35] mm, slub: optionally save/restore irqs in slab_[un]lock()/ Message-ID: <20210729154302.GF3809@techsingularity.net> References: <20210729132132.19691-1-vbabka@suse.cz> <20210729132132.19691-32-vbabka@suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Content-Disposition: inline In-Reply-To: <20210729132132.19691-32-vbabka@suse.cz> User-Agent: Mutt/1.10.1 (2018-07-13) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jul 29, 2021 at 03:21:28PM +0200, Vlastimil Babka wrote: > For PREEMPT_RT we will need to disable irqs for this bit spinlock. As a > preparation, add a flags parameter, and an internal version that takes > additional bool parameter to control irq saving/restoring (the flags > parameter is compile-time unused if the bool is a constant false). > > Convert ___cmpxchg_double_slab(), which also comes with the same bool > parameter, to use the internal version. > > Signed-off-by: Vlastimil Babka On arm64 allmodconfig, the following build warning was new In file included from ./include/linux/spinlock.h:54, from ./include/linux/mmzone.h:8, from ./include/linux/gfp.h:6, from ./include/linux/mm.h:10, from mm/slub.c:13: mm/slub.c: In function '___cmpxchg_double_slab.isra.0': ./include/linux/irqflags.h:177:3: warning: 'flags' may be used uninitialized in this function [-Wmaybe-uninitialized] 177 | arch_local_irq_restore(flags); \ | ^~~~~~~~~~~~~~~~~~~~~~ mm/slub.c:408:17: note: 'flags' was declared here 408 | unsigned long flags; | ^~~~~ In file included from ./include/linux/string.h:262, from ./include/linux/bitmap.h:10, from ./include/linux/cpumask.h:12, No idea what's special about arm allmodconfig that confuses the compiler. -- Mel Gorman SUSE Labs