tracing/ftrace: change the type of the init() callback

Impact: extend the ->init() method with the ability to fail

This bring a way to know if the initialization of a tracer successed.
A tracer must return 0 on success and a traditional error (ie:
-ENOMEM) if it fails.

If a tracer fails to init, it is free to print a detailed warn. The
tracing api will not and switch to a new tracer will just return the
error from the init callback.

Note: this will be used for the return tracer.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Frederic Weisbecker
2008-11-16 05:57:26 +01:00
committed by Ingo Molnar
parent e6e7a65aab
commit 1c80025a49
13 changed files with 88 additions and 24 deletions

View File

@ -261,11 +261,12 @@ static void stop_stack_trace(struct trace_array *tr)
mutex_unlock(&sample_timer_lock);
}
static void stack_trace_init(struct trace_array *tr)
static int stack_trace_init(struct trace_array *tr)
{
sysprof_trace = tr;
start_stack_trace(tr);
return 0;
}
static void stack_trace_reset(struct trace_array *tr)