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tracing/events: perform function tracing in event selftests

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We can find some bugs in the trace events if we stress the writes as well.
The function tracer is a good way to stress the events.

[ Impact: extend scope of event tracer self-tests ]

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20090416161746.604786131@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Steven Rostedt 2009-04-16 12:15:44 -04:00 committed by Ingo Molnar
parent 69abe6a5d1
commit 9ea21c1ecd
1 changed files with 72 additions and 6 deletions
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78
kernel/trace/trace_events.c
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@ -1017,7 +1017,7 @@ static __init void event_test_stuff(void)
* For every trace event defined, we will test each trace point separately,
* and then by groups, and finally all trace points.
*/
static __init int event_trace_self_tests(void)
static __init void event_trace_self_tests(void)
{
struct ftrace_event_call *call;
struct event_subsystem *system;
@ -1071,7 +1071,7 @@ static __init int event_trace_self_tests(void)
sysname = kstrdup(system->name, GFP_KERNEL);
if (WARN_ON(!sysname)) {
pr_warning("Can't allocate memory, giving up!\n");
return 0;
return;
}
ret = ftrace_set_clr_event(sysname, 1);
kfree(sysname);
@ -1086,7 +1086,7 @@ static __init int event_trace_self_tests(void)
sysname = kstrdup(system->name, GFP_KERNEL);
if (WARN_ON(!sysname)) {
pr_warning("Can't allocate memory, giving up!\n");
return 0;
return;
}
ret = ftrace_set_clr_event(sysname, 0);
kfree(sysname);
@ -1106,14 +1106,14 @@ static __init int event_trace_self_tests(void)
sysname = kmalloc(4, GFP_KERNEL);
if (WARN_ON(!sysname)) {
pr_warning("Can't allocate memory, giving up!\n");
return 0;
return;
}
memcpy(sysname, "*:*", 4);
ret = ftrace_set_clr_event(sysname, 1);
if (WARN_ON_ONCE(ret)) {
kfree(sysname);
pr_warning("error enabling all events\n");
return 0;
return;
}
event_test_stuff();
@ -1125,10 +1125,76 @@ static __init int event_trace_self_tests(void)
if (WARN_ON_ONCE(ret)) {
pr_warning("error disabling all events\n");
return 0;
return;
}
pr_cont("OK\n");
}
#ifdef CONFIG_FUNCTION_TRACER
static DEFINE_PER_CPU(atomic_t, test_event_disable);
static void
function_test_events_call(unsigned long ip, unsigned long parent_ip)
{
struct ring_buffer_event *event;
struct ftrace_entry *entry;
unsigned long flags;
long disabled;
int resched;
int cpu;
int pc;
pc = preempt_count();
resched = ftrace_preempt_disable();
cpu = raw_smp_processor_id();
disabled = atomic_inc_return(&per_cpu(test_event_disable, cpu));
if (disabled != 1)
goto out;
local_save_flags(flags);
event = trace_current_buffer_lock_reserve(TRACE_FN, sizeof(*entry),
flags, pc);
if (!event)
goto out;
entry = ring_buffer_event_data(event);
entry->ip = ip;
entry->parent_ip = parent_ip;
trace_current_buffer_unlock_commit(event, flags, pc);
out:
atomic_dec(&per_cpu(test_event_disable, cpu));
ftrace_preempt_enable(resched);
}
static struct ftrace_ops trace_ops __initdata =
{
.func = function_test_events_call,
};
static __init void event_trace_self_test_with_function(void)
{
register_ftrace_function(&trace_ops);
pr_info("Running tests again, along with the function tracer\n");
event_trace_self_tests();
unregister_ftrace_function(&trace_ops);
}
#else
static __init void event_trace_self_test_with_function(void)
{
}
#endif
static __init int event_trace_self_tests_init(void)
{
event_trace_self_tests();
event_trace_self_test_with_function();
return 0;
}