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[2604:1380:45e3:2400::1]) by mx.google.com with ESMTPS id 203-20020a6302d4000000b005cd84895879si4533345pgc.789.2023.12.18.15.19.32 for (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 18 Dec 2023 15:19:33 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel+bounces-4475-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:45e3:2400::1 as permitted sender) client-ip=2604:1380:45e3:2400::1; Authentication-Results: mx.google.com; dkim=pass header.i=@kernel.org header.s=k20201202 header.b=FQfMty3r; spf=pass (google.com: domain of linux-kernel+bounces-4475-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:45e3:2400::1 as permitted sender) smtp.mailfrom="linux-kernel+bounces-4475-linux.lists.archive=gmail.com@vger.kernel.org"; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=kernel.org Received: from smtp.subspace.kernel.org (wormhole.subspace.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by sv.mirrors.kernel.org (Postfix) with ESMTPS id CCEE8283362 for ; Mon, 18 Dec 2023 23:19:32 +0000 (UTC) Received: from localhost.localdomain (localhost.localdomain [127.0.0.1]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 56823768E9; Mon, 18 Dec 2023 23:19:25 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="FQfMty3r" X-Original-To: linux-kernel@vger.kernel.org Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7C56E760B3; Mon, 18 Dec 2023 23:19:23 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0AD17C433C7; Mon, 18 Dec 2023 23:19:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1702941563; bh=jz2D1HTTnvEfO7luxuGZDmFgmCccQ/8d9eqpMPiagIE=; h=From:To:Cc:Subject:Date:From; b=FQfMty3rKGcMRGiCFhNF/8By0LJBuehsUIlEc012N7BdQZbSAxVx6+t30BLbXHbYE irb40fbCYkMv3ygXAIOIWPgOgvK+Xgd4xSSEc+UhCihHi8ihC0ARxT0szXhHH6QZzd NGPvbHSkk6IEMag/r7njT5jd5+P2P1QQStyJvAAVlZNX/kFCK1EB3cFqNajkAR0zYj RuY/CbHH8+L/PSJvzs9A9EIYfFnRqmKxHEVzfPENHgygZ6G9pWjZrwi5QLkJ6Yccvw 2HB2K39TZ9dzxBPQx49F91CHr22UpicE+FBBzR+T3+O7Wypt/5MiXgOUTwanE9Yg9o 6CJS4C14bQPFw== From: Frederic Weisbecker To: LKML Cc: Frederic Weisbecker , Boqun Feng , Joel Fernandes , Neeraj Upadhyay , Uladzislau Rezki , Zqiang , rcu , "Paul E . McKenney" , Thomas Gleixner , Peter Zijlstra Subject: [PATCH 0/3] timers & RCU: Fix TREE03 stalls Date: Tue, 19 Dec 2023 00:19:13 +0100 Message-ID: <20231218231916.11719-1-frederic@kernel.org> X-Mailer: git-send-email 2.42.1 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5c0930ccaad5 ("hrtimers: Push pending hrtimers away from outgoing CPU earlier") has introduced an issue with RCU. This is a proposal to solve the situation after realizing that fixing that on the timers side wouldn't be pretty to say the least. Oh and the last patch is absolutely irrelevant to the issue... Frederic Weisbecker (3): hrtimer: Report offline hrtimer enqueue rcu: Defer RCU kthreads wakeup when CPU is dying rcu/exp: Remove full barrier upon main thread wakeup include/linux/hrtimer.h | 3 ++- kernel/rcu/tree.c | 34 +++++++++++++++++++++++++++++++++- kernel/rcu/tree_exp.h | 8 +++----- kernel/time/hrtimer.c | 3 +++ 4 files changed, 41 insertions(+), 7 deletions(-) -- 2.42.1