Received: by 2002:a25:c205:0:0:0:0:0 with SMTP id s5csp1193122ybf; Thu, 27 Feb 2020 06:36:23 -0800 (PST) X-Google-Smtp-Source: APXvYqwDf8RiQX0HwOwgRtS7V/GI6Eyco0YzQ+niEGXYiziFjOn3fI5f4ptkuomFQ3iR2uiVqhdC X-Received: by 2002:a05:6808:9ba:: with SMTP id e26mr3565303oig.81.1582814183321; Thu, 27 Feb 2020 06:36:23 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1582814183; cv=none; d=google.com; s=arc-20160816; b=jYdwbUSVRNx1bswhkWYfSGNB1jwAO0W0F4bm8bcb8JZTIap2kIL/jnwKy7x6YPqUsL 0Q/Dh5LskTvwFrEYNa1vvjibKP0v7qn6xY03+IPqhXQ7eZff2ejxofFCEOMwPeHBsPGF ymNlquVt/+CpKECJ+LZ09CdPFiIx6phq3jGoIX/4Lj66sI2PBvgZQaBaI1B3kGNWvSva uzYWyJoVMsCIGw5g/7URX8ppAYQaix8dfREDC2cyZsi0mjkzpYEN7p3PR/1lkjxEAw/f LCiTQVe7SZoEccAbOc1O3BXXsjLVeDzrRJgGwddXvD44vWf1eQjWRMCYD2wO4qQs4IF/ 7MKw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:references:in-reply-to:references :in-reply-to:message-id:date:subject:to:from:dkim-signature; bh=6jbvMBk13Qc9JtHz2Wigd/KDKE1xzu7oxDcOC045sJY=; b=lnrgWB7wITv5W2Fw0yAy5gncPJV0xyHSElsWkvcBQVF5BCh0GdrSSsamXjx8VU1AVA c1lADMcqZGgWxZPvuB/Pl2R5WGUb9ZVBJGMrDtyEUkWARs3osEvxsWMpKOVdikFEL3N9 wZSJGdB6zGAxvC1xDM6MUmWS+B7OdM9arLyTrQlNbO9gLPCglohWH0n4RyxdTfpwGJL/ oqe7O8IrTvVci7jsHBZArOsHcK3PcWmPIWzGLgMy5+VG7nod/4352+a542b/RULaezJz A3pIon5mruaFBFK0pWyXTBJ1ZYH3OMAYuIp66RywrMVh6fp4YjdzGzWzFfQOPocarAJB QJiw== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@kernel.org header.s=default header.b=gKXVK5ts; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id 24si991814oij.155.2020.02.27.06.36.11; Thu, 27 Feb 2020 06:36:23 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; dkim=pass header.i=@kernel.org header.s=default header.b=gKXVK5ts; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732869AbgB0Off (ORCPT + 99 others); Thu, 27 Feb 2020 09:35:35 -0500 Received: from mail.kernel.org ([198.145.29.99]:44980 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387481AbgB0OeA (ORCPT ); Thu, 27 Feb 2020 09:34:00 -0500 Received: from localhost.localdomain (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 0C747246AE; Thu, 27 Feb 2020 14:33:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1582814039; bh=LptIzUxwKjl42YG8Ni/qcMG8j5lOeHqwdiwER+neHwg=; h=From:To:Subject:Date:In-Reply-To:References:In-Reply-To: References:From; b=gKXVK5tsLaynaC4LSDA0PTu+6Nv76v34XRXpd9lX5QC8t2/uKms0CXxCfIDaNjXDY faWucMNZSnVJ7nZ5nJHK6KAUSRLrQpgYR6fqT4G5E4YE3qmzUIPpZ0KJ0p2sEFkkEM tGp4XGCO2ql2KN6QEGQm954UDmR35SisehS5BXFI= From: zanussi@kernel.org To: LKML , linux-rt-users , Steven Rostedt , Thomas Gleixner , Carsten Emde , John Kacur , Sebastian Andrzej Siewior , Daniel Wagner , Tom Zanussi Subject: [PATCH RT 04/23] x86: preempt: Check preemption level before looking at lazy-preempt Date: Thu, 27 Feb 2020 08:33:15 -0600 Message-Id: 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 From: Sebastian Andrzej Siewior v4.14.170-rt75-rc2 stable review patch. If anyone has any objections, please let me know. ----------- [ Upstream commit 19fc8557f2323c52b26561651ed4d51fc688a740 ] Before evaluating the lazy-preempt state it must be ensure that the preempt-count is zero. Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Tom Zanussi --- arch/x86/include/asm/preempt.h | 2 ++ 1 file changed, 2 insertions(+) diff --git a/arch/x86/include/asm/preempt.h b/arch/x86/include/asm/preempt.h index f66708779274..afa0e42ccdd1 100644 --- a/arch/x86/include/asm/preempt.h +++ b/arch/x86/include/asm/preempt.h @@ -96,6 +96,8 @@ static __always_inline bool __preempt_count_dec_and_test(void) if (____preempt_count_dec_and_test()) return true; #ifdef CONFIG_PREEMPT_LAZY + if (preempt_count()) + return false; if (current_thread_info()->preempt_lazy_count) return false; return test_thread_flag(TIF_NEED_RESCHED_LAZY); -- 2.14.1