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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 54CAAC433EF for ; Mon, 29 Nov 2021 22:44:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234609AbhK2WsI (ORCPT ); Mon, 29 Nov 2021 17:48:08 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36190 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235027AbhK2WrU (ORCPT ); Mon, 29 Nov 2021 17:47:20 -0500 Received: from galois.linutronix.de (Galois.linutronix.de [IPv6:2a0a:51c0:0:12e:550::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D3E5FC0C087D for ; Mon, 29 Nov 2021 09:48:27 -0800 (PST) From: Sebastian Andrzej Siewior DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1638208106; 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=Dkltu1kAzc9JHOgyCqJmEJlABCPHPuNKHsAFYVYIVGE=; b=FDkOqlo/LrWlcgj4BVdwsIJAHXE8YnzLEe2sDntHBVAmEw68hIlCSu292jcLTM/gJjcdB2 zlO9nG9afAxlq5Nj3BE2c7SH958dL867SSC3VWALW1o0In2ZphuL4LzNy/xhRboMucVuVO JDufHpVs0cBNw6jlgBg2+qq7YnVh3ur22UeNBZ6ozDV3B9oGrIyW9dlsgRkEdoGPG5dOcQ V5QTv9OA71Hz8kqGWaltG/RBkvuXSRPJnEpEFpU4Ykz/EtAHGawJIb25k3LJxTEtpZ0Qd3 u7LiMeUs7PvDvrLC+cAktDDAXfa2bd2dgQmB/gDsycawfmQbwhv+//YEp7dpRg== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1638208106; 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=Dkltu1kAzc9JHOgyCqJmEJlABCPHPuNKHsAFYVYIVGE=; b=9hCHf1b4nGm6XK4iBL0gQuhMGfWj52M3JgjMk7sfXhWBYAGYTMdhaOk5J3Ks9wgdrsNykN ZVYt9EQHF2Lpw5AA== To: linux-kernel@vger.kernel.org Cc: Ben Segall , Boqun Feng , Daniel Bristot de Oliveira , Dietmar Eggemann , Ingo Molnar , Juri Lelli , Mel Gorman , Peter Zijlstra , Steven Rostedt , Thomas Gleixner , Vincent Guittot , Waiman Long , Will Deacon , Sebastian Andrzej Siewior Subject: [PATCH 01/11] sched: Trigger warning if ->migration_disabled counter underflows. Date: Mon, 29 Nov 2021 18:46:44 +0100 Message-Id: <20211129174654.668506-2-bigeasy@linutronix.de> In-Reply-To: <20211129174654.668506-1-bigeasy@linutronix.de> References: <20211129174654.668506-1-bigeasy@linutronix.de> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org If migrate_enable() is used more often than its counter part then it remains undetected and rq::nr_pinned will underflow, too. Add a warning if migrate_enable() is attempted if without a matching a migrate_disable(). Signed-off-by: Sebastian Andrzej Siewior --- kernel/sched/core.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 76f9deeaa9420..02be3f6144e97 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -2171,6 +2171,8 @@ void migrate_enable(void) if (p->migration_disabled > 1) { p->migration_disabled--; return; + } else if (WARN_ON_ONCE(p->migration_disabled =3D=3D 0)) { + return; } =20 /* --=20 2.34.0