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/* SPDX-License-Identifier: GPL-2.0 */
#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/jump_label.h>
#include <linux/rseq.h>
#include <linux/tracepoint-defs.h>
#ifdef CONFIG_TRACEPOINTS
DECLARE_TRACEPOINT(rseq_update);
DECLARE_TRACEPOINT(rseq_ip_fixup);
void __rseq_trace_update(struct task_struct *t);
void __rseq_trace_ip_fixup(unsigned long ip, unsigned long start_ip,
unsigned long offset, unsigned long abort_ip);
static inline void rseq_trace_update(struct task_struct *t, struct rseq_ids *ids)
{
if (tracepoint_enabled(rseq_update) && ids)
__rseq_trace_update(t);
}
static inline void rseq_trace_ip_fixup(unsigned long ip, unsigned long start_ip,
unsigned long offset, unsigned long abort_ip)
{
if (tracepoint_enabled(rseq_ip_fixup))
__rseq_trace_ip_fixup(ip, start_ip, offset, abort_ip);
}
#else /* CONFIG_TRACEPOINT */
static inline void rseq_trace_update(struct task_struct *t, struct rseq_ids *ids) { }
static inline void rseq_trace_ip_fixup(unsigned long ip, unsigned long start_ip,
unsigned long offset, unsigned long abort_ip) { }
#endif /* !CONFIG_TRACEPOINT */
DECLARE_STATIC_KEY_MAYBE(CONFIG_RSEQ_DEBUG_DEFAULT_ENABLE, rseq_debug_enabled);
static __always_inline void rseq_note_user_irq_entry(void)
{
if (IS_ENABLED(CONFIG_GENERIC_IRQ_ENTRY))
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 */
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