From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753901AbbLDMvT (ORCPT ); Fri, 4 Dec 2015 07:51:19 -0500 Received: from casper.infradead.org ([85.118.1.10]:54980 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751117AbbLDMvR (ORCPT ); Fri, 4 Dec 2015 07:51:17 -0500 Date: Fri, 4 Dec 2015 13:51:11 +0100 From: Peter Zijlstra To: Tejun Heo Cc: Ulrich Obergfell , Ingo Molnar , Andrew Morton , linux-kernel@vger.kernel.org, kernel-team@fb.com Subject: Re: [PATCH] workqueue: warn if memory reclaim tries to flush !WQ_MEM_RECLAIM workqueue Message-ID: <20151204125111.GH17308@twins.programming.kicks-ass.net> References: <20151203093350.GP17308@twins.programming.kicks-ass.net> <20151203100018.GO11639@twins.programming.kicks-ass.net> <20151203144811.GA27463@mtj.duckdns.org> <20151203150442.GR17308@twins.programming.kicks-ass.net> <20151203150604.GC27463@mtj.duckdns.org> <20151203192616.GJ27463@mtj.duckdns.org> <20151203204313.GX17308@twins.programming.kicks-ass.net> <20151203205632.GM27463@mtj.duckdns.org> <20151203210911.GZ17308@twins.programming.kicks-ass.net> <20151203220406.GA2630@mtj.duckdns.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20151203220406.GA2630@mtj.duckdns.org> User-Agent: Mutt/1.5.21 (2012-12-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Dec 03, 2015 at 05:04:06PM -0500, Tejun Heo wrote: > > One solution is to always fail maybe_create_worker() when PF_MEMALLOC is > > set, thus always hitting the mayday button. > > I'm not following. When PF_MEMALLOC is set where? It seems I made a false assumption. I was thinking the worker creation was done from queue/flush context, but its done by other workers, at a time when PF_MEMALLOC cannot be set. In any case, no objections to the proposed patch.