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=-9.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 25F12C10F13 for ; Mon, 8 Apr 2019 19:15:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E0ED420879 for ; Mon, 8 Apr 2019 19:15:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1554750919; bh=6eCzGmVks969R3cfYzDLxLHgQcXT9gF4bP0XIW3m3ro=; h=From:To:Cc:Subject:Date:In-Reply-To:References:In-Reply-To: References:List-ID:From; b=KgTWLD8TwyVGKrjPWeA/0ZHDlIuEE1uOsAXv7ilwfiVFlvyY3B6YHovkdhn+MZxIS BzG7xZD7454kYoqbYUCzX8bWIL4/0lOuxCSm/XbJPD58mb1JaLlFMzoXw+bOYryqaS naKPVqAcpTWAMq0y9NAc0Dep3ZBgXN6P9kmIVBZw= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729098AbfDHTPS (ORCPT ); Mon, 8 Apr 2019 15:15:18 -0400 Received: from mail.kernel.org ([198.145.29.99]:45364 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728019AbfDHTOc (ORCPT ); Mon, 8 Apr 2019 15:14:32 -0400 Received: from tzanussi-mobl.hsd1.il.comcast.net (c-98-220-238-81.hsd1.il.comcast.net [98.220.238.81]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id F04C221924; Mon, 8 Apr 2019 19:14:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1554750871; bh=6eCzGmVks969R3cfYzDLxLHgQcXT9gF4bP0XIW3m3ro=; h=From:To:Cc:Subject:Date:In-Reply-To:References:In-Reply-To: References:From; b=rmbdmkEPLoCYvC2UZGw+YOryhC73IxrICTjtihmTjcvflO9p1g0u10MUcWTVUqgq9 SKaryVoX1QltDU46Ne1vdf0gtKfbs0m2Lko5zuFnnY0uRKVzgjy5N8G6gZb60yn+qn HGTtPTPrkNHsmDxhVyRvoONOLmlVTEtiAQ2QhFz0= From: Tom Zanussi To: linux-kernel@vger.kernel.org, linux-rt-users@vger.kernel.org Cc: rostedt@goodmis.org, tglx@linutronix.de, C.Emde@osadl.org, jkacur@redhat.com, bigeasy@linutronix.de, daniel.wagner@siemens.com, julia@ni.com, amartin@nvidia.com Subject: [PATCH 08/13] hrtimer: Don't lose state in cpu_chill() Date: Mon, 8 Apr 2019 14:14:10 -0500 Message-Id: <53a19e573f13967322ba8221fcf121948803ccf4.1554737688.git.tom.zanussi@linux.intel.com> X-Mailer: git-send-email 2.14.1 In-Reply-To: References: In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.14.109-rt58-rc1 stable review patch. If anyone has any objections, please let me know. ------------------ From: Sebastian Andrzej Siewior [ Upstream commit 585456236766349f692f9fbcc089d71411831f88 ] In cpu_chill() the state is set to TASK_UNINTERRUPTIBLE and a timer is programmed. On return the state is always TASK_RUNNING which means we lose the state if it was something other than RUNNING. Also set_current_state() sets ->task_state_change to within cpu_chill() which is not expected. Save the task state on entry and restore it on return. Simply set the state in order to avoid updating ->task_state_change. Cc: stable-rt@vger.kernel.org Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Tom Zanussi --- kernel/time/hrtimer.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c index c8d806126381..6da6b5dded3c 100644 --- a/kernel/time/hrtimer.c +++ b/kernel/time/hrtimer.c @@ -1866,15 +1866,18 @@ void cpu_chill(void) { ktime_t chill_time; unsigned int freeze_flag = current->flags & PF_NOFREEZE; + long saved_state; + saved_state = current->state; chill_time = ktime_set(0, NSEC_PER_MSEC); - set_current_state(TASK_UNINTERRUPTIBLE); + __set_current_state_no_track(TASK_UNINTERRUPTIBLE); current->flags |= PF_NOFREEZE; sleeping_lock_inc(); schedule_hrtimeout(&chill_time, HRTIMER_MODE_REL_HARD); sleeping_lock_dec(); if (!freeze_flag) current->flags &= ~PF_NOFREEZE; + __set_current_state_no_track(saved_state); } EXPORT_SYMBOL(cpu_chill); #endif -- 2.14.1