Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932089Ab3DXGsS (ORCPT ); Wed, 24 Apr 2013 02:48:18 -0400 Received: from mail-ea0-f181.google.com ([209.85.215.181]:35757 "EHLO mail-ea0-f181.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754609Ab3DXGsR (ORCPT ); Wed, 24 Apr 2013 02:48:17 -0400 Date: Wed, 24 Apr 2013 08:48:13 +0200 From: Ingo Molnar To: Dave Jones , Peter Zijlstra , Ingo Molnar , Linux Kernel Subject: Re: Print out additional debugging advice when we hit lockdep BUGs Message-ID: <20130424064813.GB27551@gmail.com> References: <20130423163403.GA12839@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20130423163403.GA12839@redhat.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1750 Lines: 48 * Dave Jones wrote: > We occasionally get reports of these BUGs being hit, and the stack trace > doesn't necessarily always tell us what we need to know about why we are > hitting those limits. > > If users start attaching /proc/lock_stats to reports we may have more of > a clue what's going on. Good idea. A detail: > printk("BUG: MAX_STACK_TRACE_ENTRIES too low!\n"); > printk("turning off the locking correctness validator.\n"); > + printk("Attach output of /proc/lock_stat to bug report\n"); > printk("BUG: MAX_LOCKDEP_KEYS too low!\n"); > printk("turning off the locking correctness validator.\n"); > + printk("Attach output of /proc/lock_stat to bug report\n"); > printk("BUG: MAX_LOCKDEP_ENTRIES too low!\n"); > printk("turning off the locking correctness validator.\n"); > + printk("Attach output of /proc/lock_stat to bug report\n"); > printk("BUG: MAX_LOCKDEP_CHAINS too low!\n"); > printk("turning off the locking correctness validator.\n"); > + printk("Attach output of /proc/lock_stat to bug report\n"); > printk("BUG: MAX_LOCK_DEPTH too low, depth: %i max: %lu!\n", > curr->lockdep_depth, MAX_LOCK_DEPTH); > printk("turning off the locking correctness validator.\n"); > + printk("Attach output of /proc/lock_stat to bug report\n"); These patterns repeated in 4 places really call for a common helper defined as print_lockdep_off(fmt...) or so? (Can be a followup patch if that's easier for you.) Thanks, Ingo -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/