From 5478648ee8258ba11fa7ed5471d535f34b80965e Mon Sep 17 00:00:00 2001 From: "Steven Rostedt (VMware)" Date: Sun, 18 Nov 2018 17:28:53 -0500 Subject: [PATCH] powerpc/function_graph: Simplify with function_graph_enter() commit fe60522ec60082a1dd735691b82c64f65d4ad15e 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 powerpc 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: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: Michael Ellerman Cc: linuxppc-dev@lists.ozlabs.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/powerpc/kernel/trace/ftrace.c | 15 ++------------- 1 file changed, 2 insertions(+), 13 deletions(-) diff --git a/arch/powerpc/kernel/trace/ftrace.c b/arch/powerpc/kernel/trace/ftrace.c index 4bfbb54dee51..19ef4f5866b6 100644 --- a/arch/powerpc/kernel/trace/ftrace.c +++ b/arch/powerpc/kernel/trace/ftrace.c @@ -697,7 +697,6 @@ int ftrace_disable_ftrace_graph_caller(void) */ unsigned long prepare_ftrace_return(unsigned long parent, unsigned long ip) { - struct ftrace_graph_ent trace; unsigned long return_hooker; if (unlikely(ftrace_graph_is_dead())) @@ -708,18 +707,8 @@ unsigned long prepare_ftrace_return(unsigned long parent, unsigned long ip) return_hooker = ppc_function_entry(return_to_handler); - 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 = return_hooker; + if (!function_graph_enter(parent, ip, 0, NULL)) + parent = return_hooker; out: return parent; } -- GitLab