linux/kernel/user-return-notifier.c

// SPDX-License-Identifier: GPL-2.0-only

#include <linux/user-return-notifier.h>
#include <linux/percpu.h>
#include <linux/sched.h>
#include <linux/export.h>

static DEFINE_PER_CPU(struct hlist_head, return_notifier_list);

/*
 * Request a notification when the current cpu returns to userspace.  Must be
 * called in atomic context.  The notifier will also be called in atomic
 * context.
 */
void user_return_notifier_register(struct user_return_notifier *urn)
{ … }
EXPORT_SYMBOL_GPL(…);

/*
 * Removes a registered user return notifier.  Must be called from atomic
 * context, and from the same cpu registration occurred in.
 */
void user_return_notifier_unregister(struct user_return_notifier *urn)
{ … }
EXPORT_SYMBOL_GPL(…);

/* Calls registered user return notifiers */
void fire_user_return_notifiers(void)
{ … }