4.19-stable review patch. If anyone has any objections, please let me know.
------------------ From: Steven Rostedt (VMware) <[email protected]> commit bc715ee4dbc5db462c59b9cfba92d31b3274fe3a 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 superh 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: Yoshinori Sato <[email protected]> Cc: Rich Felker <[email protected]> Cc: [email protected] Cc: [email protected] Fixes: 03274a3ffb449 ("tracing/fgraph: Adjust fgraph depth before calling trace return callback") Reviewed-by: Masami Hiramatsu <[email protected]> Signed-off-by: Steven Rostedt (VMware) <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- arch/sh/kernel/ftrace.c | 16 ++-------------- 1 file changed, 2 insertions(+), 14 deletions(-) --- a/arch/sh/kernel/ftrace.c +++ b/arch/sh/kernel/ftrace.c @@ -321,8 +321,7 @@ int ftrace_disable_ftrace_graph_caller(v void prepare_ftrace_return(unsigned long *parent, unsigned long self_addr) { unsigned long old; - int faulted, err; - struct ftrace_graph_ent trace; + int faulted; unsigned long return_hooker = (unsigned long)&return_to_handler; if (unlikely(ftrace_graph_is_dead())) @@ -365,18 +364,7 @@ void prepare_ftrace_return(unsigned long return; } - err = ftrace_push_return_trace(old, self_addr, &trace.depth, 0, NULL); - if (err == -EBUSY) { + if (function_graph_enter(old, self_addr, 0, NULL)) __raw_writel(old, parent); - return; - } - - trace.func = self_addr; - - /* Only trace if the calling function expects to */ - if (!ftrace_graph_entry(&trace)) { - current->curr_ret_stack--; - __raw_writel(old, parent); - } } #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
