ftrace: add ftrace_kill_atomic

It has been suggested that I add a way to disable the function tracer
on an oops. This code adds a ftrace_kill_atomic. It is not meant to be
used in normal situations. It will disable the ftrace tracer, but will
not perform the nice shutdown that requires scheduling.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Cc: Steven Rostedt <srostedt@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Steven Rostedt 2008-07-10 20:58:15 -04:00 committed by Ingo Molnar
parent 26bc83f4cb
commit a2bb6a3d85
2 changed files with 16 additions and 0 deletions

View File

@ -89,6 +89,7 @@ void ftrace_enable_daemon(void);
/* totally disable ftrace - can not re-enable after this */
void ftrace_kill(void);
void ftrace_kill_atomic(void);
static inline void tracer_disable(void)
{

View File

@ -1601,6 +1601,21 @@ core_initcall(ftrace_dynamic_init);
# define ftrace_force_shutdown() do { } while (0)
#endif /* CONFIG_DYNAMIC_FTRACE */
/**
* ftrace_kill_atomic - kill ftrace from critical sections
*
* This function should be used by panic code. It stops ftrace
* but in a not so nice way. If you need to simply kill ftrace
* from a non-atomic section, use ftrace_kill.
*/
void ftrace_kill_atomic(void)
{
ftrace_disabled = 1;
ftrace_enabled = 0;
ftraced_suspend = -1;
clear_ftrace_function();
}
/**
* ftrace_kill - totally shutdown ftrace
*