From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Dumazet Subject: Re: [PATCH RT] net: move xmit_recursion to per-task variable on -RT Date: Thu, 14 Jan 2016 14:20:04 -0800 Message-ID: <1452810004.1223.154.camel@edumazet-glaptop2.roam.corp.google.com> References: <20160113152352.GH29964@linutronix.de> <20160114145007.GC17776@linutronix.de> <56981AE1.20202@stressinduktion.org> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Cc: Sebastian Andrzej Siewior , Thomas Gleixner , linux-rt-users@vger.kernel.org, linux-kernel@vger.kernel.org, Steven Rostedt , netdev@vger.kernel.org To: Hannes Frederic Sowa Return-path: Received: from mail-pa0-f45.google.com ([209.85.220.45]:34911 "EHLO mail-pa0-f45.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754957AbcANWUG (ORCPT ); Thu, 14 Jan 2016 17:20:06 -0500 In-Reply-To: <56981AE1.20202@stressinduktion.org> Sender: netdev-owner@vger.kernel.org List-ID: On Thu, 2016-01-14 at 23:02 +0100, Hannes Frederic Sowa wrote: > We are just adding a second recursion limit solely to openvswitch which > has the same problem: > > https://patchwork.ozlabs.org/patch/566769/ > > This time also we depend on rcu_read_lock marking the section being > nonpreemptible. Nice would be a more generic solution here which doesn't > need to always add something to *current. Note that rcu_read_lock() does not imply that preemption is disabled.