From: Andy Lutomirski <luto@kernel.org> Date: Fri, 3 Jul 2015 19:44:21 +0000 (-0700) Subject: context_tracking: Add ct_state() and CT_WARN_ON() X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=f9281648ecd5081803bb2da84b9ccb0cf48436cd;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git context_tracking: Add ct_state() and CT_WARN_ON() This will let us sprinkle sanity checks around the kernel without making too much of a mess. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Denys Vlasenko <vda.linux@googlemail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: paulmck@linux.vnet.ibm.com Link: http://lkml.kernel.org/r/5da41fb2ceb29eac671f427c67040401ba2a1fa0.1435952415.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org> --- diff --git a/include/linux/context_tracking.h b/include/linux/context_tracking.h index b96bd299966f..008fc67d0d96 100644 --- a/include/linux/context_tracking.h +++ b/include/linux/context_tracking.h @@ -49,13 +49,28 @@ static inline void exception_exit(enum ctx_state prev_ctx) } } + +/** + * 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) { } static inline enum ctx_state exception_enter(void) { return 0; } static inline void exception_exit(enum ctx_state prev_ctx) { } +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 678ecdf90cf6..ee956c528fab 100644 --- a/include/linux/context_tracking_state.h +++ b/include/linux/context_tracking_state.h @@ -14,6 +14,7 @@ struct context_tracking { bool active; int recursion; enum ctx_state { + CONTEXT_DISABLED = -1, /* returned by ct_state() if unknown */ CONTEXT_KERNEL = 0, CONTEXT_USER, CONTEXT_GUEST,