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 E5871C4332F for ; Mon, 6 Dec 2021 15:39:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1385573AbhLFPnN (ORCPT ); Mon, 6 Dec 2021 10:43:13 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56888 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1386664AbhLFP0u (ORCPT ); Mon, 6 Dec 2021 10:26:50 -0500 Received: from galois.linutronix.de (Galois.linutronix.de [IPv6:2a0a:51c0:0:12e:550::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D10A0C061354; Mon, 6 Dec 2021 07:17:22 -0800 (PST) Date: Mon, 06 Dec 2021 15:15:50 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1638803751; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=iJQf/9nrvDzpoXrQFytyK1Bn+kAavcB53pXJuJLKM/8=; b=3wHX2C/Sha4t8YKIMx5/ES7gNfTSOUzy6FWFdn30tfq4TZP3czNjWpnfOpohTguXu1yRNG d/8K8C7kP8gjdUObE+jQ3J8Z9vraKyaLmP32YgIrdh/0eOBSlE0EEIpb1KPl/WdO8P9Hgl oqKeSLqvTRY9mtULgvPlNj0y0RceHrPRb81qtpjIEUyDGQy1/PVzuWdYRwxdc5NXDwDGwh ENrtoPhFsiZKQtu6VwwzD/U0SpsIQ5vECMKarqWmJ51o5fGSApPihMOUGecnDCKKFw41az Eq2Y5YvO1GTBQkXb+3P/xkSJJ1tiRL6jRTO5QlkhJ3b7tHJTV6yPMGPVoveZKA== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1638803751; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=iJQf/9nrvDzpoXrQFytyK1Bn+kAavcB53pXJuJLKM/8=; b=plwbOJKL2UV1df+bJ145ScO3NFQGbF/Cnh3wVB/gqdsYxDCAPbXDleOphHOsHqqkPPQs5v CpWOrciWq0SL/eAg== From: "tip-bot2 for Sebastian Andrzej Siewior" Sender: tip-bot2@linutronix.de Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: locking/core] sched: Trigger warning if ->migration_disabled counter underflows. Cc: Sebastian Andrzej Siewior , "Peter Zijlstra (Intel)" , x86@kernel.org, linux-kernel@vger.kernel.org In-Reply-To: <20211129174654.668506-2-bigeasy@linutronix.de> References: <20211129174654.668506-2-bigeasy@linutronix.de> MIME-Version: 1.0 Message-ID: <163880375014.11128.11566339706185975718.tip-bot2@tip-bot2> Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The following commit has been merged into the locking/core branch of tip: Commit-ID: 9d0df37797453f168afdb2e6fd0353c73718ae9a Gitweb: https://git.kernel.org/tip/9d0df37797453f168afdb2e6fd0353c73718ae9a Author: Sebastian Andrzej Siewior AuthorDate: Mon, 29 Nov 2021 18:46:44 +01:00 Committer: Peter Zijlstra CommitterDate: Sat, 04 Dec 2021 10:56:22 +01:00 sched: Trigger warning if ->migration_disabled counter underflows. 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 Signed-off-by: Peter Zijlstra (Intel) Link: https://lore.kernel.org/r/20211129174654.668506-2-bigeasy@linutronix.de --- kernel/sched/core.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 3c9b0fd..300218a 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -2173,6 +2173,9 @@ void migrate_enable(void) return; } + if (WARN_ON_ONCE(!p->migration_disabled)) + return; + /* * Ensure stop_task runs either before or after this, and that * __set_cpus_allowed_ptr(SCA_MIGRATE_ENABLE) doesn't schedule().