diff options
| author |   Huang Ying <ying.huang@intel.com> | 2008-08-15 00:40:25 -0700 |
|---|---|---|
| committer |   Linus Torvalds <torvalds@linux-foundation.org> | 2008-08-15 08:35:42 -0700 |
| commit | 9bdeb7b5d34f197dea7859d24475943395ffea5e (patch) | |
| tree | f2db04f16f95ac713bb35d9c0dc8626a294d6d60 /include | |
| parent | kexec jump: in sync with hibernation implementation (diff) | |
| download | linux-dev-9bdeb7b5d34f197dea7859d24475943395ffea5e.tar.xz linux-dev-9bdeb7b5d34f197dea7859d24475943395ffea5e.zip | |
kexec jump: __ftrace_enabled_save/restore
Add __ftrace_enabled_save/restore, used to disable ftrace for a while.
Now, this is used by kexec jump, which need a version without lock, for
general situation, a locked version should be used.
Signed-off-by: Huang Ying <ying.huang@intel.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/ftrace.h | 21 |
1 files changed, 21 insertions, 0 deletions
diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index f368d041e02d..bb384068272e 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -98,6 +98,27 @@ static inline void tracer_disable(void) #endif } +/* Ftrace disable/restore without lock. Some synchronization mechanism + * must be used to prevent ftrace_enabled to be changed between + * disable/restore. */ +static inline int __ftrace_enabled_save(void) +{ +#ifdef CONFIG_FTRACE + int saved_ftrace_enabled = ftrace_enabled; + ftrace_enabled = 0; + return saved_ftrace_enabled; +#else + return 0; +#endif +} + +static inline void __ftrace_enabled_restore(int enabled) +{ +#ifdef CONFIG_FTRACE + ftrace_enabled = enabled; +#endif +} + #ifdef CONFIG_FRAME_POINTER /* TODO: need to fix this for ARM */ # define CALLER_ADDR0 ((unsigned long)__builtin_return_address(0)) |