Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932218AbbLEA77 (ORCPT ); Fri, 4 Dec 2015 19:59:59 -0500 Received: from relay4-d.mail.gandi.net ([217.70.183.196]:55318 "EHLO relay4-d.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755485AbbLEA7y (ORCPT ); Fri, 4 Dec 2015 19:59:54 -0500 Date: Fri, 4 Dec 2015 16:59:48 -0800 From: Josh Triplett To: "Paul E. McKenney" Cc: linux-kernel@vger.kernel.org, mingo@kernel.org, jiangshanlai@gmail.com, dipankar@in.ibm.com, akpm@linux-foundation.org, mathieu.desnoyers@efficios.com, tglx@linutronix.de, peterz@infradead.org, rostedt@goodmis.org, dhowells@redhat.com, edumazet@google.com, dvhart@linux.intel.com, fweisbec@gmail.com, oleg@redhat.com, bobby.prani@gmail.com Subject: Re: [PATCH tip/core/rcu 2/8] rcutorture: Dump stack when GP kthread stalls Message-ID: <20151205005948.GA27128@cloud> References: <20151205002331.GA27249@linux.vnet.ibm.com> <1449275032-28206-2-git-send-email-paulmck@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1449275032-28206-2-git-send-email-paulmck@linux.vnet.ibm.com> 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 Content-Length: 1683 Lines: 47 On Fri, Dec 04, 2015 at 04:23:46PM -0800, Paul E. McKenney wrote: > This commit increases debug information in the case where the grace-period > kthread is being prevented from running by dumping that kthread's stack. That's not everything this patch does; see below. > Signed-off-by: Paul E. McKenney > --- > kernel/rcu/tree.c | 7 +++++-- > 1 file changed, 5 insertions(+), 2 deletions(-) > > diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c > index 81aa1cdc6bc9..7b78c88e19a3 100644 > --- a/kernel/rcu/tree.c > +++ b/kernel/rcu/tree.c > @@ -1196,12 +1196,15 @@ static void rcu_check_gp_kthread_starvation(struct rcu_state *rsp) > > j = jiffies; > gpa = READ_ONCE(rsp->gp_activity); > - if (j - gpa > 2 * HZ) > + if (j - gpa > 2 * HZ) { > pr_err("%s kthread starved for %ld jiffies! g%lu c%lu f%#x s%d ->state=%#lx\n", > rsp->name, j - gpa, > rsp->gpnum, rsp->completed, > rsp->gp_flags, rsp->gp_state, > - rsp->gp_kthread ? rsp->gp_kthread->state : 0); > + rsp->gp_kthread ? rsp->gp_kthread->state : ~0); The commit message doesn't explain this change. Could you please 1) document this change in the commit message, and 2) split it into a separate patch unless it directly relates to the other change (which doesn't seem like the case)? > + if (rsp->gp_kthread) > + sched_show_task(rsp->gp_kthread); > + } > } > > /* > -- > 2.5.2 > -- 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/