From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756354AbaLHSkt (ORCPT ); Mon, 8 Dec 2014 13:40:49 -0500 Received: from mail-qa0-f50.google.com ([209.85.216.50]:49694 "EHLO mail-qa0-f50.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755780AbaLHSkr (ORCPT ); Mon, 8 Dec 2014 13:40:47 -0500 Date: Mon, 8 Dec 2014 13:40:35 -0500 From: Tejun Heo To: Andrew Morton Cc: linux-kernel@vger.kernel.org, Lai Jiangshan , Linus Torvalds , Ingo Molnar Subject: Re: [PATCH wq/for-3.19 3/3] workqueue: dump workqueues on sysrq-t Message-ID: <20141208184035.GE12274@htj.dyndns.org> References: <20141208174326.GB12274@htj.dyndns.org> <20141208174406.GC12274@htj.dyndns.org> <20141208174733.GD12274@htj.dyndns.org> <20141208100613.ecc66d89.akpm@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20141208100613.ecc66d89.akpm@linux-foundation.org> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, Andrew. On Mon, Dec 08, 2014 at 10:06:13AM -0800, Andrew Morton wrote: > sysrq-t already produces thousands of lines of output. Maybe create a > new keycode for this? Believe it or not, we already used up all alphanumerics if we count in the arch-specific ones. Given that the workqueue information would primarily be useful in tracking down hangs and we'd want to see the dump of tasks in that case anyway, sysrq-t isn't a bad fit for appending workqueue dump. If anybody has a better idea, I'm all ears. ... > > +static void pr_cont_pool_info(struct worker_pool *pool) > > +{ > > + if (pool->cpu >= 0) > > + pr_cont(" cpu=%d", pool->cpu); > > + else if (pool->node != NUMA_NO_NODE) > > + pr_cont(" node=%d", pool->node); > > + > > + if (pool->cpu < 0) { > > + static char cpus_buf[PAGE_SIZE]; > > Ouch. This could be [NR_CPUS + epsilon]? It's bitmap mask printing so each char can show four cpus. PAGE_SIZE should be enough for now but I think we need cpumask_prcont(). > > +static void pr_cont_work(bool comma, struct work_struct *work) > > +{ > > + if (work->func == wq_barrier_func) { > > + struct wq_barrier *barr = > > + container_of(work, struct wq_barrier, work); > > Can avoid the 80-col contortions with > > struct wq_barrier *barr; > > barr = container_of(work, struct wq_barrier, work); I'm not sure either is any better, but sure. > > + if (has_in_flight) { > > + bool comma = false; > > + > > + printk(" in-flight:"); > > pr_something? show_state() uses KERN_INFO, which may or may not be > appropriate. Hmmm, best to match show_state(). I'll convert to pr_info(). Thanks. -- tejun