This will let us sprinkle sanity checks around the kernel without making too much of a mess.
Signed-off-by: Andy Lutomirski <[email protected]> --- include/linux/context_tracking.h | 15 +++++++++++++++ include/linux/context_tracking_state.h | 1 + 2 files changed, 16 insertions(+) diff --git a/include/linux/context_tracking.h b/include/linux/context_tracking.h index 2821838256b4..3f5ac9b86f69 100644 --- a/include/linux/context_tracking.h +++ b/include/linux/context_tracking.h @@ -57,6 +57,19 @@ static inline void context_tracking_task_switch(struct task_struct *prev, if (context_tracking_is_enabled()) __context_tracking_task_switch(prev, next); } + +/** + * ct_state() - return the current context tracking state if known + * + * Returns the current cpu's context tracking state if context tracking + * is enabled. If context tracking is disabled, returns + * CONTEXT_DISABLED. This should be used primarily for debugging. + */ +static inline enum ctx_state ct_state(void) +{ + return context_tracking_is_enabled() ? + this_cpu_read(context_tracking.state) : CONTEXT_DISABLED; +} #else static inline void user_enter(void) { } static inline void user_exit(void) { } @@ -64,8 +77,10 @@ static inline enum ctx_state exception_enter(void) { return 0; } static inline void exception_exit(enum ctx_state prev_ctx) { } static inline void context_tracking_task_switch(struct task_struct *prev, struct task_struct *next) { } +static inline enum ctx_state ct_state(void) { return CONTEXT_DISABLED; } #endif /* !CONFIG_CONTEXT_TRACKING */ +#define CT_WARN_ON(cond) WARN_ON(context_tracking_is_enabled() && (cond)) #ifdef CONFIG_CONTEXT_TRACKING_FORCE extern void context_tracking_init(void); diff --git a/include/linux/context_tracking_state.h b/include/linux/context_tracking_state.h index 6b7b96a32b75..d4aec2805849 100644 --- a/include/linux/context_tracking_state.h +++ b/include/linux/context_tracking_state.h @@ -13,6 +13,7 @@ struct context_tracking { */ bool active; enum ctx_state { + CONTEXT_DISABLED = -1, /* returned by ct_state() if unknown */ CONTEXT_KERNEL = 0, CONTEXT_USER, CONTEXT_GUEST, -- 2.4.3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
