Commit-ID: f9281648ecd5081803bb2da84b9ccb0cf48436cd Gitweb: http://git.kernel.org/tip/f9281648ecd5081803bb2da84b9ccb0cf48436cd Author: Andy Lutomirski <l...@kernel.org> AuthorDate: Fri, 3 Jul 2015 12:44:21 -0700 Committer: Ingo Molnar <mi...@kernel.org> CommitDate: Tue, 7 Jul 2015 10:59:04 +0200
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 <l...@kernel.org> Cc: Andy Lutomirski <l...@amacapital.net> Cc: Borislav Petkov <b...@alien8.de> Cc: Brian Gerst <brge...@gmail.com> Cc: Denys Vlasenko <dvlas...@redhat.com> Cc: Denys Vlasenko <vda.li...@googlemail.com> Cc: Frederic Weisbecker <fweis...@gmail.com> Cc: H. Peter Anvin <h...@zytor.com> Cc: Kees Cook <keesc...@chromium.org> Cc: Linus Torvalds <torva...@linux-foundation.org> Cc: Oleg Nesterov <o...@redhat.com> Cc: Peter Zijlstra <pet...@infradead.org> Cc: Rik van Riel <r...@redhat.com> Cc: Thomas Gleixner <t...@linutronix.de> Cc: paul...@linux.vnet.ibm.com Link: http://lkml.kernel.org/r/5da41fb2ceb29eac671f427c67040401ba2a1fa0.1435952415.git.l...@kernel.org Signed-off-by: Ingo Molnar <mi...@kernel.org> --- 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 b96bd29..008fc67 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 678ecdf..ee956c5 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, -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
