linux_dsm_epyc7002/include/linux/context_tracking_state.h
Andy Lutomirski f9281648ec 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>
2015-07-07 10:59:04 +02:00

50 lines
1.3 KiB
C

#ifndef _LINUX_CONTEXT_TRACKING_STATE_H
#define _LINUX_CONTEXT_TRACKING_STATE_H
#include <linux/percpu.h>
#include <linux/static_key.h>
struct context_tracking {
/*
* When active is false, probes are unset in order
* to minimize overhead: TIF flags are cleared
* and calls to user_enter/exit are ignored. This
* may be further optimized using static keys.
*/
bool active;
int recursion;
enum ctx_state {
CONTEXT_DISABLED = -1, /* returned by ct_state() if unknown */
CONTEXT_KERNEL = 0,
CONTEXT_USER,
CONTEXT_GUEST,
} state;
};
#ifdef CONFIG_CONTEXT_TRACKING
extern struct static_key context_tracking_enabled;
DECLARE_PER_CPU(struct context_tracking, context_tracking);
static inline bool context_tracking_is_enabled(void)
{
return static_key_false(&context_tracking_enabled);
}
static inline bool context_tracking_cpu_is_enabled(void)
{
return __this_cpu_read(context_tracking.active);
}
static inline bool context_tracking_in_user(void)
{
return __this_cpu_read(context_tracking.state) == CONTEXT_USER;
}
#else
static inline bool context_tracking_in_user(void) { return false; }
static inline bool context_tracking_active(void) { return false; }
static inline bool context_tracking_is_enabled(void) { return false; }
static inline bool context_tracking_cpu_is_enabled(void) { return false; }
#endif /* CONFIG_CONTEXT_TRACKING */
#endif