tracing: Add ref_data to function and fgraph tracer structs

The selftest for function and function graph tracers are defined as
__init, as they are only executed at boot up. The "tracer" structs
that are associated to those tracers are not setup as __init as they
are used after boot. To stop mismatch warnings, those structures
need to be annotated with __ref_data.

Currently, the tracer structures are defined to __read_mostly, as they
do not really change. But in the future they should be converted to
consts, but that will take a little work because they have a "next"
pointer that gets updated when they are registered. That will have to
wait till the next major release.

Link: http://lkml.kernel.org/r/1373596735.17876.84.camel@gandalf.local.home

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Reported-by: Chen Gang <gang.chen@asianux.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
This commit is contained in:
Steven Rostedt (Red Hat) 2013-07-18 14:41:51 -04:00 committed by Steven Rostedt
parent f77d09a384
commit 8f76899339
3 changed files with 11 additions and 2 deletions

View File

@ -680,6 +680,15 @@ extern int trace_selftest_startup_sched_switch(struct tracer *trace,
struct trace_array *tr);
extern int trace_selftest_startup_branch(struct tracer *trace,
struct trace_array *tr);
/*
* Tracer data references selftest functions that only occur
* on boot up. These can be __init functions. Thus, when selftests
* are enabled, then the tracers need to reference __init functions.
*/
#define __tracer_data __refdata
#else
/* Tracers are seldom changed. Optimize when selftests are disabled. */
#define __tracer_data __read_mostly
#endif /* CONFIG_FTRACE_STARTUP_TEST */
extern void *head_page(struct trace_array_cpu *data);

View File

@ -199,7 +199,7 @@ static int func_set_flag(u32 old_flags, u32 bit, int set)
return 0;
}
static struct tracer function_trace __read_mostly =
static struct tracer function_trace __tracer_data =
{
.name = "function",
.init = function_trace_init,

View File

@ -1448,7 +1448,7 @@ static struct trace_event graph_trace_ret_event = {
.funcs = &graph_functions
};
static struct tracer graph_trace __read_mostly = {
static struct tracer graph_trace __tracer_data = {
.name = "function_graph",
.open = graph_trace_open,
.pipe_open = graph_trace_open,