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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7C7BEC369A1 for ; Mon, 7 Apr 2025 18:21:27 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id C16E46B000A; Mon, 7 Apr 2025 14:21:24 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id B9EAD6B000C; Mon, 7 Apr 2025 14:21:24 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 9F3BE6B000D; Mon, 7 Apr 2025 14:21:24 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0017.hostedemail.com [216.40.44.17]) by kanga.kvack.org (Postfix) with ESMTP id 666576B000C for ; Mon, 7 Apr 2025 14:21:24 -0400 (EDT) Received: from smtpin13.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay04.hostedemail.com (Postfix) with ESMTP id E16B91A1478 for ; Mon, 7 Apr 2025 18:21:24 +0000 (UTC) X-FDA: 83308065288.13.AC5BAF9 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by imf16.hostedemail.com (Postfix) with ESMTP id 324DC180005 for ; Mon, 7 Apr 2025 18:21:23 +0000 (UTC) Authentication-Results: imf16.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b=ARTtZ2RD; dmarc=pass (policy=quarantine) header.from=redhat.com; spf=pass (imf16.hostedemail.com: domain of agruenba@redhat.com designates 170.10.133.124 as permitted sender) smtp.mailfrom=agruenba@redhat.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1744050083; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=r207ou57TRn4Q0BVpY2sMaqzJuM7STz+41u9bkzpKR4=; b=RQugX2Iobgk3Ubm3YjkwCA3IgVlAHfpHQ23ZIYXVAPt2yY/ByZwDhsnbcg1VdXTJHu+sl5 MoTdGYmdKnEFcb6ZhnhkIyucHAgaNN9FmBqnyMA0wVjuCA1+MR1fZ0b3p/1ikJDPBgvz6w yHZ6FaurGt0A5KrAjQzyTVCZ/uA89gA= ARC-Authentication-Results: i=1; imf16.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b=ARTtZ2RD; dmarc=pass (policy=quarantine) header.from=redhat.com; spf=pass (imf16.hostedemail.com: domain of agruenba@redhat.com designates 170.10.133.124 as permitted sender) smtp.mailfrom=agruenba@redhat.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1744050083; a=rsa-sha256; cv=none; b=PHPZOo58uhNA1qCb4y2PkuEpz/2d/vWT6Htb4sEqy0Z9TjJPDePcfkFrqPkB1uYxuo39vq EIn2TQSb0SOAV5aYDtACRa7ziHrNmMff9tokVIE2104BYwOSVVbrmcI/mIrvHIC/MbbUR0 LTWr4mxIoGaV6H1EM7CxI5kkXfzKjOQ= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1744050082; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=r207ou57TRn4Q0BVpY2sMaqzJuM7STz+41u9bkzpKR4=; b=ARTtZ2RDpvXQeWIE77O1yzU0JJm5dD8OXCeGGTaKmCMNkNlr+RVhZZoCx9HfDiObh4+QDD +JyZ2H2tMa7WR7Hrl2nb2Aat3px4b29y4L9gnF8yB62RKOe9AowVeG74RuxMeNIhPV5t6U XlNv3nmfcLfDobKF+R2Ap97c//BSKGo= Received: from mx-prod-mc-06.mail-002.prod.us-west-2.aws.redhat.com (ec2-35-165-154-97.us-west-2.compute.amazonaws.com [35.165.154.97]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-662-K0TaAE15OlaiLMNeZtQo6Q-1; Mon, 07 Apr 2025 14:21:18 -0400 X-MC-Unique: K0TaAE15OlaiLMNeZtQo6Q-1 X-Mimecast-MFC-AGG-ID: K0TaAE15OlaiLMNeZtQo6Q_1744050076 Received: from mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.93]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 7899318001F6; Mon, 7 Apr 2025 18:21:16 +0000 (UTC) Received: from pasta.fast.eng.rdu2.dc.redhat.com (unknown [10.45.224.15]) by mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 352CB1828AA8; Mon, 7 Apr 2025 18:21:12 +0000 (UTC) From: Andreas Gruenbacher To: cgroups@vger.kernel.org Cc: Jan Kara , Tetsuo Handa , Rafael Aquini , gfs2@lists.linux.dev, linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, Andreas Gruenbacher Subject: [RFC 2/2] writeback: Fix false warning in inode_to_wb() Date: Mon, 7 Apr 2025 20:21:02 +0200 Message-ID: <20250407182104.716631-3-agruenba@redhat.com> In-Reply-To: <20250407182104.716631-1-agruenba@redhat.com> References: <20250407182104.716631-1-agruenba@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.93 X-Rspamd-Server: rspam11 X-Rspamd-Queue-Id: 324DC180005 X-Stat-Signature: z58hqe88fq9w35cjfm7geets75ukmhuc X-Rspam-User: X-HE-Tag: 1744050083-512760 X-HE-Meta: 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 kH9+AHsR 95EeaaVKLRuBbAZ++Ci5VPvoqiabRd8uKvfguuKRJo6pJ+ppUkhtYct7QlE8N9EBJ94toao9TgpqUEbcviSABC2gcIZMovv39bYyVR3+4xiTQ3Az1WchQYN3NTd9l9EYyxPCGIRFtMyNnO7QcUrxwf4zPlFAcgngZD8iCJZ9EWTKWUw24J/vwRGoomASFYLhUagEa6ZIIL4ByFz4zFsJ5/x/iSiCP5wxZD84GKtcGGqY19l9xX4J81gaMGaHx+0m78a9dRuKfwvqlKP/NrgSq1QAOHEdmGnwWPEGbfrSVPM2PhYR3oG+rPAw+23g7IT81lpQ7su4acdy00xEOC8fz+lcWQBRqyeAo0Mb4BWcqdF+V7x6QhfR91Vf/IeXl8YvJhRNC 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: List-Subscribe: List-Unsubscribe: From: Jan Kara inode_to_wb() is used also for filesystems that don't support cgroup writeback. For these filesystems inode->i_wb is stable during the lifetime of the inode (it points to bdi->wb) and there's no need to hold locks protecting the inode->i_wb dereference. Improve the warning in inode_to_wb() to not trigger for these filesystems. Signed-off-by: Jan Kara Reviewed-by: Andreas Gruenbacher --- include/linux/backing-dev.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/include/linux/backing-dev.h b/include/linux/backing-dev.h index 8e7af9a03b41..4069a027582f 100644 --- a/include/linux/backing-dev.h +++ b/include/linux/backing-dev.h @@ -245,10 +245,11 @@ wb_get_create_current(struct backing_dev_info *bdi, gfp_t gfp) * holding either @inode->i_lock, the i_pages lock, or the * associated wb's list_lock. */ -static inline struct bdi_writeback *inode_to_wb(const struct inode *inode) +static inline struct bdi_writeback *inode_to_wb(struct inode *inode) { #ifdef CONFIG_LOCKDEP WARN_ON_ONCE(debug_locks && + inode_cgwb_enabled(inode) && (!lockdep_is_held(&inode->i_lock) && !lockdep_is_held(&inode->i_mapping->i_pages.xa_lock) && !lockdep_is_held(&inode->i_wb->list_lock))); -- 2.48.1