From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752654AbdHKHze (ORCPT ); Fri, 11 Aug 2017 03:55:34 -0400 Received: from mout.gmx.net ([212.227.17.21]:50155 "EHLO mout.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751545AbdHKHzc (ORCPT ); Fri, 11 Aug 2017 03:55:32 -0400 Message-ID: <1502438116.16425.18.camel@gmx.de> Subject: [patch-rt] hotplug, hrtimer: Migrate expired/deferred timers during cpu offline From: Mike Galbraith To: Sebastian Andrzej Siewior Cc: Thomas Gleixner , LKML , linux-rt-users , Steven Rostedt Date: Fri, 11 Aug 2017 09:55:16 +0200 In-Reply-To: <1502186459.8042.31.camel@gmx.de> References: <20170804173823.lzuhnejlnxczr2lj@linutronix.de> <1501913583.7917.42.camel@gmx.de> <1501945043.5473.31.camel@gmx.de> <20170807073350.nwytftryfp34mrwi@linutronix.de> <1502094121.5568.22.camel@gmx.de> <1502186459.8042.31.camel@gmx.de> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.20.5 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit X-Provags-ID: V03:K0:MZt/R0A+iC9rb27MAgex32gXj8PGqedSq5gjsGr5jLr9IIvw62c LKQ/Tl0GgoxSVNYcEVgstVLlDQ+IcA0ZmLWN9fU7Kkv7pUkJBia2+cWWSTBhyVft5KWQUJq 45WScK7F13NKP1wS74kJn9/EIH9t/c1MsBDqo2xBv6RIvK8rezlTD29M57Gb0Sp7hDOJUNZ /gIBPajSGPg45Ls740dqg== X-UI-Out-Filterresults: notjunk:1;V01:K0:n4Nip/HZbec=:2bjc+WfCpMoeTXwwhyd/6C knajuS7CNkpiXakBuFUD5a1KGk4dJlizhNq+xBMmBnS5gwPSZnlWCuiheCfBAZB+RgEkvDAUN tl5jbD2AOxO73BiFUP+N8d07u+wJYHgr40hMOhQt/HJJryjXw+hPKiz5XFAZZNARCxcOi5U2F C/IEp141Dyto6eAdOaO76sV0UPcPrbSORryGEoO7mgmxUgWGOgMVxx8r5gUH+pEwuIOITrvbF 6F4gdruVLqnf3wxoDfa+cj0nY4uZaMeE+dWnzv0pTSb1Y2OO33S1pFrKegEjJwLxr7qsZJiof /qNBjEzJv5j86K8jln+d11Hqx6sD0U8o7mPxkdsmx7RUZ6vpMd/Bzi63PVQWaRpLOYPcuMkNo TUirISiRYFTqRGzdjfRikh6e8d/MzAKcAUHegFNyFieAZrOrbIuEJenU1Nx0/3+w08L/Zaeor AQP2+DHg5qRsSyrXpLMV2353A7d6y9YKRh+XKG6SsXmuy2imSAODumjzuB9JvrrQ1DD+QuPzx wPyBHPF0XRXVQXnqo9Itke2/vA1kpY8PwG2KYRGnJP1/Q/pw71PN7nhv3j++ItY2Tw1KTkr4o ts5lqk0Fxpe5M3LyI4NjW0FyKu1r6ddVwUtJ6z0dcSshGQ1mOOAM/pbVMVCYGVySd74p0LWu6 1sTt2EXgf+mW3sjEF71eTEAKC4+pSoNTf04fKYJtHXaQryaHVeqHNyGQC1Gcc4MEK6gqj29f6 AG7ijx+p1sTVT/pKtY46Z3O7+t9k5pDnQpu5Vds5kF9j5oU5Q9rKqzO+ii8sDb/qpVKd/j6FQ vUl26UoIzQDczIQptrFlT4lJQR1CUW6BV4M2W9SSoyQXJCeHn0= Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The below fixes the list debug explosion up. If we do not migrate expired/deferred timers during cpu offline, ->cb_entry will be corrupted by online initialization of base->expired, leading to a loud list debug complaint should someone call __remove_hrtimer() thereafter. Signed-off-by: Mike Galvraith --- kernel/time/hrtimer.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) --- a/kernel/time/hrtimer.c +++ b/kernel/time/hrtimer.c @@ -1802,6 +1802,19 @@ static void migrate_hrtimer_list(struct */ enqueue_hrtimer(timer, new_base); } + + /* + * Finally, migrate any expired timers deferred by RT. + */ + while (!list_empty(&old_base->expired)) { + struct list_head *entry = old_base->expired.next; + + timer = container_of(entry, struct hrtimer, cb_entry); + /* XXX: hm, perhaps defer again instead of enqueueing. */ + __remove_hrtimer(timer, old_base, HRTIMER_STATE_ENQUEUED, 0); + timer->base = new_base; + enqueue_hrtimer(timer, new_base); + } } int hrtimers_dead_cpu(unsigned int scpu)