ftrace: add ftrace_off_permanent

Impact: add new API to disable all of ftrace on anomalies

It case of a serious anomaly being detected (like something caught by
lockdep) it is a good idea to disable all tracing immediately, without
grabing any locks.

This patch adds ftrace_off_permanent that disables the tracers, function
tracing and ring buffers without a way to enable them again. This should
only be used when something serious has been detected.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Steven Rostedt 2008-11-21 12:59:38 -05:00 committed by Ingo Molnar
parent e58918ab9d
commit 69bb54ec05
2 changed files with 17 additions and 0 deletions

View file

@ -257,6 +257,7 @@ extern int ftrace_dump_on_oops;
extern void tracing_start(void);
extern void tracing_stop(void);
extern void ftrace_off_permanent(void);
extern void
ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3);
@ -290,6 +291,7 @@ ftrace_printk(const char *fmt, ...) __attribute__ ((format (printf, 1, 0)));
static inline void tracing_start(void) { }
static inline void tracing_stop(void) { }
static inline void ftrace_off_permanent(void) { }
static inline int
ftrace_printk(const char *fmt, ...)
{