Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
        id S1751872AbdL0NJN (ORCPT <rfc822;w@1wt.eu>);
        Wed, 27 Dec 2017 08:09:13 -0500
Received: from mail-lf0-f43.google.com ([209.85.215.43]:44442 "EHLO
        mail-lf0-f43.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
        with ESMTP id S1751000AbdL0NJM (ORCPT
        <rfc822;linux-kernel@vger.kernel.org>);
        Wed, 27 Dec 2017 08:09:12 -0500
X-Google-Smtp-Source: ACJfBosm0+txpOxoS4s0WKyWQdHCcAgcLrqDBMnkL4stglv7fPuw5CKkLK9FJxLWFZAaumNTbNkWRA==
To: "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
From: Nikita Yushchenko <nikita.yoush@cogentembedded.com>
Subject: cancel_work_sync() can cause priority invertion
Message-ID: <c7cd8b98-5b94-6c4f-b3d7-419854983a23@cogentembedded.com>
Date: Wed, 27 Dec 2017 16:09:08 +0300
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101
 Thunderbird/52.5.0
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Language: en-US
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org
Content-Length: 273
Lines: 10

Hi

For those who care about linux RT behavior:

while analyzing traces, just found priority inversion caused by RT task
calling cancel_work_sync(), while work item in question is executing in
non-RT kworker that was preempted for significant time.

WBR,
Nikita Yushchenko