From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Message-ID: <20181122003332.940703297@goodmis.org> Date: Wed, 21 Nov 2018 19:28:12 -0500 From: Steven Rostedt Subject: [for-next][PATCH 11/18] s390/function_graph: Simplify with function_graph_entry() References: <20181122002801.501220343@goodmis.org> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Sender: linux-arch-owner@vger.kernel.org Message-ID: <20181122002812.0MD33NKJrHdHyjd8dSH8npW9El1SgHKXOY7ebKpBOx4@z> List-Archive: List-Post: To: linux-kernel@vger.kernel.org Cc: Linus Torvalds , Ingo Molnar , Andrew Morton , Thomas Gleixner , Peter Zijlstra , linux-arch@vger.kernel.org, Joel Fernandes , Masami Hiramatsu , Josh Poimboeuf , Andy Lutomirski , Frederic Weisbecker , Martin Schwidefsky , Heiko Carstens , Julian Wiedmann , linux-s390@vger.kernel.org, stable@kernel.org List-ID: From: "Steven Rostedt (VMware)" The function_graph_entry() 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. Cc: 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") Signed-off-by: Steven Rostedt (VMware) --- arch/s390/kernel/ftrace.c | 13 ++----------- 1 file changed, 2 insertions(+), 11 deletions(-) diff --git a/arch/s390/kernel/ftrace.c b/arch/s390/kernel/ftrace.c index 84be7f02d0c2..39b13d71a8fe 100644 --- 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; } -- 2.19.1