From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934699AbbI2Kdi (ORCPT ); Tue, 29 Sep 2015 06:33:38 -0400 Received: from bombadil.infradead.org ([198.137.202.9]:37793 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934590AbbI2KdW (ORCPT ); Tue, 29 Sep 2015 06:33:22 -0400 Date: Tue, 29 Sep 2015 12:27:55 +0200 From: Peter Zijlstra To: mingo@kernel.org Cc: linux-kernel@vger.kernel.org, torvalds@linux-foundation.org, fweisbec@gmail.com, oleg@redhat.com, umgwanakikbuti@gmail.com, tglx@linutronix.de, rostedt@goodmis.org Subject: [RFC][PATCH 12/11] sched: Add preempt_count invariant check Message-ID: <20150929102755.GD3816@twins.programming.kicks-ass.net> References: <20150929092825.540553633@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20150929092825.540553633@infradead.org> User-Agent: Mutt/1.5.21 (2012-12-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Ingo requested I keep my debug check for the preempt_count invariant. Requested-by: Ingo Molnar Signed-off-by: Peter Zijlstra (Intel) --- kernel/sched/core.c | 5 +++++ 1 file changed, 5 insertions(+) --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -2503,6 +2503,11 @@ static struct rq *finish_task_switch(str struct mm_struct *mm = rq->prev_mm; long prev_state; + if (unlikely(WARN_ONCE(preempt_count() != 2, + "corrupted preempt_count: %s/%d/0x%x\n", + current->comm, current->pid, preempt_count()))) + preempt_count_set(INIT_PREEMPT_COUNT); + rq->prev_mm = NULL; /*