ftrace: Remove global function list and call function directly
Instead of having a list of global functions that are called,
as only one global function is allow to be enabled at a time, there's
no reason to have a list.
Instead, simply have all the users of the global ops, use the global ops
directly, instead of registering their own ftrace_ops. Just switch what
function is used before enabling the function tracer.
This removes a lot of code as well as the complexity involved with it.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
diff --git a/kernel/trace/trace_irqsoff.c b/kernel/trace/trace_irqsoff.c
index 8ff02cb..b5cb047 100644
--- a/kernel/trace/trace_irqsoff.c
+++ b/kernel/trace/trace_irqsoff.c
@@ -151,12 +151,6 @@
atomic_dec(&data->disabled);
}
-
-static struct ftrace_ops trace_ops __read_mostly =
-{
- .func = irqsoff_tracer_call,
- .flags = FTRACE_OPS_FL_GLOBAL | FTRACE_OPS_FL_RECURSION_SAFE,
-};
#endif /* CONFIG_FUNCTION_TRACER */
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
@@ -531,7 +525,7 @@
}
#endif /* CONFIG_PREEMPT_TRACER */
-static int register_irqsoff_function(int graph, int set)
+static int register_irqsoff_function(struct trace_array *tr, int graph, int set)
{
int ret;
@@ -543,7 +537,7 @@
ret = register_ftrace_graph(&irqsoff_graph_return,
&irqsoff_graph_entry);
else
- ret = register_ftrace_function(&trace_ops);
+ ret = register_ftrace_function(tr->ops);
if (!ret)
function_enabled = true;
@@ -551,7 +545,7 @@
return ret;
}
-static void unregister_irqsoff_function(int graph)
+static void unregister_irqsoff_function(struct trace_array *tr, int graph)
{
if (!function_enabled)
return;
@@ -559,17 +553,17 @@
if (graph)
unregister_ftrace_graph();
else
- unregister_ftrace_function(&trace_ops);
+ unregister_ftrace_function(tr->ops);
function_enabled = false;
}
-static void irqsoff_function_set(int set)
+static void irqsoff_function_set(struct trace_array *tr, int set)
{
if (set)
- register_irqsoff_function(is_graph(), 1);
+ register_irqsoff_function(tr, is_graph(), 1);
else
- unregister_irqsoff_function(is_graph());
+ unregister_irqsoff_function(tr, is_graph());
}
static int irqsoff_flag_changed(struct trace_array *tr, u32 mask, int set)
@@ -577,7 +571,7 @@
struct tracer *tracer = tr->current_trace;
if (mask & TRACE_ITER_FUNCTION)
- irqsoff_function_set(set);
+ irqsoff_function_set(tr, set);
return trace_keep_overwrite(tracer, mask, set);
}
@@ -586,7 +580,7 @@
{
int ret;
- ret = register_irqsoff_function(graph, 0);
+ ret = register_irqsoff_function(tr, graph, 0);
if (!ret && tracing_is_enabled())
tracer_enabled = 1;
@@ -600,7 +594,7 @@
{
tracer_enabled = 0;
- unregister_irqsoff_function(graph);
+ unregister_irqsoff_function(tr, graph);
}
static void __irqsoff_tracer_init(struct trace_array *tr)
@@ -617,7 +611,11 @@
smp_wmb();
tracing_reset_online_cpus(&tr->trace_buffer);
- if (start_irqsoff_tracer(tr, is_graph()))
+ ftrace_init_array_ops(tr, irqsoff_tracer_call);
+
+ /* Only toplevel instance supports graph tracing */
+ if (start_irqsoff_tracer(tr, (tr->flags & TRACE_ARRAY_FL_GLOBAL &&
+ is_graph())))
printk(KERN_ERR "failed to start irqsoff tracer\n");
}
@@ -630,6 +628,7 @@
set_tracer_flag(tr, TRACE_ITER_LATENCY_FMT, lat_flag);
set_tracer_flag(tr, TRACE_ITER_OVERWRITE, overwrite_flag);
+ ftrace_reset_array_ops(tr);
}
static void irqsoff_tracer_start(struct trace_array *tr)