From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757341AbaD2Ad0 (ORCPT ); Mon, 28 Apr 2014 20:33:26 -0400 Received: from e32.co.us.ibm.com ([32.97.110.150]:59708 "EHLO e32.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933064AbaD2AZt (ORCPT ); Mon, 28 Apr 2014 20:25:49 -0400 From: "Paul E. McKenney" To: linux-kernel@vger.kernel.org Cc: mingo@kernel.org, laijs@cn.fujitsu.com, dipankar@in.ibm.com, akpm@linux-foundation.org, mathieu.desnoyers@efficios.com, josh@joshtriplett.org, niv@us.ibm.com, tglx@linutronix.de, peterz@infradead.org, rostedt@goodmis.org, dhowells@redhat.com, edumazet@google.com, darren@dvhart.com, fweisbec@gmail.com, oleg@redhat.com, sbw@mit.edu, "Paul E. McKenney" Subject: [PATCH tip/core/rcu 26/45] torture: Dump ftrace buffer when the RCU grace period stalls Date: Mon, 28 Apr 2014 17:25:14 -0700 Message-Id: <1398731133-18925-26-git-send-email-paulmck@linux.vnet.ibm.com> X-Mailer: git-send-email 1.8.1.5 In-Reply-To: <1398731133-18925-1-git-send-email-paulmck@linux.vnet.ibm.com> References: <20140429002455.GA15461@linux.vnet.ibm.com> <1398731133-18925-1-git-send-email-paulmck@linux.vnet.ibm.com> X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 14042900-0928-0000-0000-0000018D1377 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: "Paul E. McKenney" This commit adds a call to rcutorture_trace_dump() to dump the ftrace buffer when the RCU grace period stalls in order to help debug the stall. Note that this is different than the RCU CPU stall warning, as it is rcutorture detecting the stall rather than the underlying RCU implementation. Signed-off-by: Paul E. McKenney --- kernel/rcu/rcutorture.c | 1 + 1 file changed, 1 insertion(+) diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c index 0141fcff6bb9..50c26a7b6d97 100644 --- a/kernel/rcu/rcutorture.c +++ b/kernel/rcu/rcutorture.c @@ -1033,6 +1033,7 @@ rcu_torture_printk(char *page) "??? Writer stall state %d g%lu c%lu f%#x\n", rcu_torture_writer_state, gpnum, completed, flags); + rcutorture_trace_dump(); } rtcv_snap = rcu_torture_current_version; } -- 1.8.1.5