From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-it0-f71.google.com (mail-it0-f71.google.com [209.85.214.71]) by kanga.kvack.org (Postfix) with ESMTP id 832726B0005 for ; Thu, 30 Jun 2016 13:54:58 -0400 (EDT) Received: by mail-it0-f71.google.com with SMTP id 13so194571854itl.0 for ; Thu, 30 Jun 2016 10:54:58 -0700 (PDT) Received: from mail-it0-x242.google.com (mail-it0-x242.google.com. [2607:f8b0:4001:c0b::242]) by mx.google.com with ESMTPS id x195si49456itx.92.2016.06.30.10.54.57 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 30 Jun 2016 10:54:57 -0700 (PDT) Received: by mail-it0-x242.google.com with SMTP id h190so9805834ith.3 for ; Thu, 30 Jun 2016 10:54:57 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <20160630165248.GB4650@linux.vnet.ibm.com> References: <20160629164415.GG4650@linux.vnet.ibm.com> <20160629181208.GP4650@linux.vnet.ibm.com> <20160630074710.GC30114@js1304-P5Q-DELUXE> <20160630132401.GT4650@linux.vnet.ibm.com> <20160630151838.GW4650@linux.vnet.ibm.com> <20160630165248.GB4650@linux.vnet.ibm.com> From: Geert Uytterhoeven Date: Thu, 30 Jun 2016 19:54:56 +0200 Message-ID: Subject: Re: Boot failure on emev2/kzm9d (was: Re: [PATCH v2 11/11] mm/slab: lockless decision to grow cache) Content-Type: text/plain; charset=UTF-8 Sender: owner-linux-mm@kvack.org List-ID: To: Paul McKenney Cc: Joonsoo Kim , Linux-Renesas , Andrew Morton , David Rientjes , "linux-kernel@vger.kernel.org" , Pekka Enberg , Linux MM , Jesper Dangaard Brouer , Christoph Lameter , "linux-arm-kernel@lists.infradead.org" Hi Paul, On Thu, Jun 30, 2016 at 6:52 PM, Paul E. McKenney wrote: > On Thu, Jun 30, 2016 at 05:53:42PM +0200, Geert Uytterhoeven wrote: >> +void rcu_dump_rcu_sched_tree(void) >> +{ >> + struct rcu_head rh; >> + unsigned long flags; >> + >> + rcu_dump_rcu_node_tree(&rcu_sched_state); /* Initial state. */ >> + local_irq_save(flags); >> + // call_rcu(&rh, do_nothing_cb); >> + local_irq_restore(flags); >> + // schedule_timeout_uninterruptible(5 * HZ); /* Or whatever delay. */ >> + rcu_dump_rcu_node_tree(&rcu_sched_state); /* GP state. */ >> + //synchronize_sched(); /* Probably hangs. */ >> + //rcu_barrier(); /* Drop RCU's references to rh before return. */ >> +} >> >> When enabling any of the 4 commented-out lines in rcu_dump_rcu_sched_tree(), >> it will lock up. > > OK, but that includes schedule_timeout_uninterruptible(5 * HZ), right? Yes it does. Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org