From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.kernel.org ([198.145.29.99]:44468 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727152AbeLDK7e (ORCPT ); Tue, 4 Dec 2018 05:59:34 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Martin Schwidefsky , Heiko Carstens , Julian Wiedmann , linux-s390@vger.kernel.org, stable@kernel.org, Masami Hiramatsu , "Steven Rostedt (VMware)" Subject: [PATCH 4.19 108/139] s390/function_graph: Simplify with function_graph_enter() Date: Tue, 4 Dec 2018 11:49:49 +0100 Message-Id: <20181204103655.015541285@linuxfoundation.org> In-Reply-To: <20181204103649.950154335@linuxfoundation.org> References: <20181204103649.950154335@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: 4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Steven Rostedt (VMware) commit 18588e1487b19e45bd90bd55ec8d3a1d44f3257f upstream. The function_graph_enter() function does the work of calling the function graph hook function and the management of the shadow stack, simplifying the work done in the architecture dependent prepare_ftrace_return(). Have s390 use the new code, and remove the shadow stack management as well as having to set up the trace structure. This is needed to prepare for a fix of a design bug on how the curr_ret_stack is used. Acked-by: Martin Schwidefsky Cc: Heiko Carstens Cc: Julian Wiedmann Cc: linux-s390@vger.kernel.org Cc: stable@kernel.org Fixes: 03274a3ffb449 ("tracing/fgraph: Adjust fgraph depth before calling trace return callback") Reviewed-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (VMware) Signed-off-by: Greg Kroah-Hartman --- arch/s390/kernel/ftrace.c | 13 ++----------- 1 file changed, 2 insertions(+), 11 deletions(-) --- a/arch/s390/kernel/ftrace.c +++ b/arch/s390/kernel/ftrace.c @@ -203,22 +203,13 @@ device_initcall(ftrace_plt_init); */ unsigned long prepare_ftrace_return(unsigned long parent, unsigned long ip) { - struct ftrace_graph_ent trace; - if (unlikely(ftrace_graph_is_dead())) goto out; if (unlikely(atomic_read(¤t->tracing_graph_pause))) goto out; ip -= MCOUNT_INSN_SIZE; - trace.func = ip; - trace.depth = current->curr_ret_stack + 1; - /* Only trace if the calling function expects to. */ - if (!ftrace_graph_entry(&trace)) - goto out; - if (ftrace_push_return_trace(parent, ip, &trace.depth, 0, - NULL) == -EBUSY) - goto out; - parent = (unsigned long) return_to_handler; + if (!function_graph_enter(parent, ip, 0, NULL)) + parent = (unsigned long) return_to_handler; out: return parent; }