diff options
Diffstat (limited to 'include/linux/rseq_entry.h')
| -rw-r--r-- | include/linux/rseq_entry.h | 49 |
1 files changed, 49 insertions, 0 deletions
diff --git a/include/linux/rseq_entry.h b/include/linux/rseq_entry.h index 5be507a127eb..ff9080b89be3 100644 --- a/include/linux/rseq_entry.h +++ b/include/linux/rseq_entry.h @@ -2,6 +2,37 @@ #ifndef _LINUX_RSEQ_ENTRY_H #define _LINUX_RSEQ_ENTRY_H +/* Must be outside the CONFIG_RSEQ guard to resolve the stubs */ +#ifdef CONFIG_RSEQ_STATS +#include <linux/percpu.h> + +struct rseq_stats { + unsigned long exit; + unsigned long signal; + unsigned long slowpath; + unsigned long ids; + unsigned long cs; + unsigned long clear; + unsigned long fixup; +}; + +DECLARE_PER_CPU(struct rseq_stats, rseq_stats); + +/* + * Slow path has interrupts and preemption enabled, but the fast path + * runs with interrupts disabled so there is no point in having the + * preemption checks implied in __this_cpu_inc() for every operation. + */ +#ifdef RSEQ_BUILD_SLOW_PATH +#define rseq_stat_inc(which) this_cpu_inc((which)) +#else +#define rseq_stat_inc(which) raw_cpu_inc((which)) +#endif + +#else /* CONFIG_RSEQ_STATS */ +#define rseq_stat_inc(x) do { } while (0) +#endif /* !CONFIG_RSEQ_STATS */ + #ifdef CONFIG_RSEQ #include <linux/rseq.h> @@ -39,8 +70,26 @@ static __always_inline void rseq_note_user_irq_entry(void) current->rseq.event.user_irq = true; } +static __always_inline void rseq_exit_to_user_mode(void) +{ + struct rseq_event *ev = ¤t->rseq.event; + + rseq_stat_inc(rseq_stats.exit); + + if (IS_ENABLED(CONFIG_DEBUG_RSEQ)) + WARN_ON_ONCE(ev->sched_switch); + + /* + * Ensure that event (especially user_irq) is cleared when the + * interrupt did not result in a schedule and therefore the + * rseq processing did not clear it. + */ + ev->events = 0; +} + #else /* CONFIG_RSEQ */ static inline void rseq_note_user_irq_entry(void) { } +static inline void rseq_exit_to_user_mode(void) { } #endif /* !CONFIG_RSEQ */ #endif /* _LINUX_RSEQ_ENTRY_H */ |