[for-next][PATCH 13/15] function_graph: Do not update pid func if CONFIG_DYNAMIC_FTRACE not enabled

From: Steven Rostedt
Date: Thu Jun 06 2024 - 08:14:42 EST


From: "Steven Rostedt (Google)" <rostedt@xxxxxxxxxxx>

The ftrace subops is only defined if CONFIG_DYNAMIC_FTRACE is enabled. If
it is not, function tracing is extremely limited, and the subops in the
ftrace_ops structure is not defined (and will fail to compile). If
DYNAMIC_FTRACE is not enabled, then function graph filtering will not
work (as it shouldn't).

Link: https://lore.kernel.org/linux-trace-kernel/20240605202709.096020676@xxxxxxxxxxx

Cc: Mark Rutland <mark.rutland@xxxxxxx>
Cc: Mathieu Desnoyers <mathieu.desnoyers@xxxxxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Fixes: df3ec5da6a1e7 ("function_graph: Add pid tracing back to function graph tracer")
Reported-by: kernel test robot <lkp@xxxxxxxxx>
Closes: https://lore.kernel.org/oe-kbuild-all/202406051855.9VIYXbTB-lkp@xxxxxxxxx/
Acked-by: Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx>
Signed-off-by: Steven Rostedt (Google) <rostedt@xxxxxxxxxxx>
---
kernel/trace/fgraph.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/kernel/trace/fgraph.c b/kernel/trace/fgraph.c
index 63d828054c79..c0e428c87ea5 100644
--- a/kernel/trace/fgraph.c
+++ b/kernel/trace/fgraph.c
@@ -1177,6 +1177,7 @@ void fgraph_update_pid_func(void)
if (!(graph_ops.flags & FTRACE_OPS_FL_INITIALIZED))
return;

+#ifdef CONFIG_DYNAMIC_FTRACE
list_for_each_entry(op, &graph_ops.subop_list, list) {
if (op->flags & FTRACE_OPS_FL_PID) {
gops = container_of(op, struct fgraph_ops, ops);
@@ -1186,6 +1187,7 @@ void fgraph_update_pid_func(void)
static_call_update(fgraph_func, gops->entryfunc);
}
}
+#endif
}

/* Allocate a return stack for each task */
--
2.43.0