path: root/arch/parisc/kernel/ftrace.c
diff options
authorSteven Rostedt (VMware) <rostedt@goodmis.org>2018-11-18 17:27:43 -0500
committerSteven Rostedt (VMware) <rostedt@goodmis.org>2018-11-27 20:30:52 -0500
commita87532c78d291265efadc4b20a8c7a70cd59ea29 (patch)
tree7104750625d5ddba9685354cbb3163e68424e36d /arch/parisc/kernel/ftrace.c
parentnds32: function_graph: Simplify with function_graph_enter() (diff)
parisc: function_graph: Simplify with function_graph_enter()
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 parisc 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: "James E.J. Bottomley" <jejb@parisc-linux.org> Cc: Helge Deller <deller@gmx.de> Cc: linux-parisc@vger.kernel.org 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>
Diffstat (limited to '')
1 files changed, 3 insertions, 14 deletions
diff --git a/arch/parisc/kernel/ftrace.c b/arch/parisc/kernel/ftrace.c
index 6fa8535d3cce..e46a4157a894 100644
--- a/arch/parisc/kernel/ftrace.c
+++ b/arch/parisc/kernel/ftrace.c
@@ -30,7 +30,6 @@ static void __hot prepare_ftrace_return(unsigned long *parent,
unsigned long self_addr)
unsigned long old;
- struct ftrace_graph_ent trace;
extern int parisc_return_to_handler;
if (unlikely(ftrace_graph_is_dead()))
@@ -41,19 +40,9 @@ static void __hot prepare_ftrace_return(unsigned long *parent,
old = *parent;
- trace.func = self_addr;
- trace.depth = current->curr_ret_stack + 1;
- /* Only trace if the calling function expects to */
- if (!ftrace_graph_entry(&trace))
- return;
- if (ftrace_push_return_trace(old, self_addr, &trace.depth,
- 0, NULL) == -EBUSY)
- return;
- /* activate parisc_return_to_handler() as return point */
- *parent = (unsigned long) &parisc_return_to_handler;
+ if (!function_graph_enter(old, self_addr, 0, NULL))
+ /* activate parisc_return_to_handler() as return point */
+ *parent = (unsigned long) &parisc_return_to_handler;