From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752867Ab3AWUgs (ORCPT ); Wed, 23 Jan 2013 15:36:48 -0500 Received: from hrndva-omtalb.mail.rr.com ([71.74.56.122]:20969 "EHLO hrndva-omtalb.mail.rr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752335Ab3AWUef (ORCPT ); Wed, 23 Jan 2013 15:34:35 -0500 X-Authority-Analysis: v=2.0 cv=bJmU0YCZ c=1 sm=0 a=rXTBtCOcEpjy1lPqhTCpEQ==:17 a=mNMOxpOpBa8A:10 a=Ciwy3NGCPMMA:10 a=MeYQtMFjgLsA:10 a=5SG0PmZfjMsA:10 a=bbbx4UPp9XUA:10 a=meVymXHHAAAA:8 a=crS0yvFignIA:10 a=20KFwNOVAAAA:8 a=FmuBU-rodUV_qrTzYOYA:9 a=jEp0ucaQiEUA:10 a=jeBq3FmKZ4MA:10 a=rXTBtCOcEpjy1lPqhTCpEQ==:117 X-Cloudmark-Score: 0 X-Authenticated-User: X-Originating-IP: 74.67.115.198 Message-Id: <20130123203433.845671704@goodmis.org> User-Agent: quilt/0.60-1 Date: Wed, 23 Jan 2013 15:30:06 -0500 From: Steven Rostedt To: linux-kernel@vger.kernel.org Cc: Ingo Molnar , Andrew Morton , Frederic Weisbecker Subject: [PATCH 04/12 -next] ftrace: Fix global function tracers that are not recursion safe References: <20130123203002.957226869@goodmis.org> Content-Disposition: inline; filename=0004-ftrace-Fix-global-function-tracers-that-are-not-recu.patch Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Steven Rostedt If one of the function tracers set by the global ops is not recursion safe, it can still be called directly without the added recursion supplied by the ftrace infrastructure. Signed-off-by: Steven Rostedt --- kernel/trace/ftrace.c | 18 ++++++++++++++++-- 1 file changed, 16 insertions(+), 2 deletions(-) diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 6e34dc1..789cbec 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -221,10 +221,24 @@ static void update_global_ops(void) * registered callers. */ if (ftrace_global_list == &ftrace_list_end || - ftrace_global_list->next == &ftrace_list_end) + ftrace_global_list->next == &ftrace_list_end) { func = ftrace_global_list->func; - else + /* + * As we are calling the function directly. + * If it does not have recursion protection, + * the function_trace_op needs to be updated + * accordingly. + */ + if (ftrace_global_list->flags & FTRACE_OPS_FL_RECURSION_SAFE) + global_ops.flags |= FTRACE_OPS_FL_RECURSION_SAFE; + else + global_ops.flags &= ~FTRACE_OPS_FL_RECURSION_SAFE; + } else { func = ftrace_global_list_func; + /* The list has its own recursion protection. */ + global_ops.flags |= FTRACE_OPS_FL_RECURSION_SAFE; + } + /* If we filter on pids, update to use the pid function */ if (!list_empty(&ftrace_pids)) { -- 1.7.10.4