diff options
| author | Steven Rostedt (VMware) <rostedt@goodmis.org> | 2018-11-18 17:10:15 -0500 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-12-05 19:32:09 +0100 |
| commit | 67d7bec3fc6c129807b22d39cb12edab2420baab (patch) | |
| tree | 2ab8fae046fb74e584e8a9485e6287d8c21fd41c /kernel | |
| parent | b72fc1c3cce457d3e9753abf52fe7f1627dd1bf3 (diff) | |
function_graph: Create function_graph_enter() to consolidate architecture code
commit 8114865ff82e200b383e46821c25cb0625b842b5 upstream.
Currently all the architectures do basically the same thing in preparing the
function graph tracer on entry to a function. This code can be pulled into a
generic location and then this will allow the function graph tracer to be
fixed, as well as extended.
Create a new function graph helper function_graph_enter() that will call the
hook function (ftrace_graph_entry) and the shadow stack operation
(ftrace_push_return_trace), and remove the need of the architecture code to
manage the shadow stack.
This is needed to prepare for a fix of a design bug on how the curr_ret_stack
is used.
Cc: stable@kernel.org
Fixes: 03274a3ffb449 ("tracing/fgraph: Adjust fgraph depth before calling trace return callback")
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/trace/trace_functions_graph.c | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c index 169b3c44ee97..28f2602435d0 100644 --- a/kernel/trace/trace_functions_graph.c +++ b/kernel/trace/trace_functions_graph.c @@ -182,6 +182,22 @@ ftrace_push_return_trace(unsigned long ret, unsigned long func, int *depth, return 0; } +int function_graph_enter(unsigned long ret, unsigned long func, + unsigned long frame_pointer, unsigned long *retp) +{ + struct ftrace_graph_ent trace; + + trace.func = func; + trace.depth = current->curr_ret_stack + 1; + + /* Only trace if the calling function expects to */ + if (!ftrace_graph_entry(&trace)) + return -EBUSY; + + return ftrace_push_return_trace(ret, func, &trace.depth, + frame_pointer, retp); +} + /* Retrieve a function return address to the trace stack on thread info.*/ static void ftrace_pop_return_trace(struct ftrace_graph_ret *trace, unsigned long *ret, |