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- /* SPDX-License-Identifier: GPL-2.0-only */
- #ifndef LINUX_RESUME_USER_MODE_H
- #define LINUX_RESUME_USER_MODE_H
- #include <linux/sched.h>
- #include <linux/task_work.h>
- #include <linux/memcontrol.h>
- #include <linux/blk-cgroup.h>
- /**
- * set_notify_resume - cause resume_user_mode_work() to be called
- * @task: task that will call resume_user_mode_work()
- *
- * Calling this arranges that @task will call resume_user_mode_work()
- * before returning to user mode. If it's already running in user mode,
- * it will enter the kernel and call resume_user_mode_work() soon.
- * If it's blocked, it will not be woken.
- */
- static inline void set_notify_resume(struct task_struct *task)
- {
- if (!test_and_set_tsk_thread_flag(task, TIF_NOTIFY_RESUME))
- kick_process(task);
- }
- /**
- * resume_user_mode_work - Perform work before returning to user mode
- * @regs: user-mode registers of @current task
- *
- * This is called when %TIF_NOTIFY_RESUME has been set. Now we are
- * about to return to user mode, and the user state in @regs can be
- * inspected or adjusted. The caller in arch code has cleared
- * %TIF_NOTIFY_RESUME before the call. If the flag gets set again
- * asynchronously, this will be called again before we return to
- * user mode.
- *
- * Called without locks.
- */
- static inline void resume_user_mode_work(struct pt_regs *regs)
- {
- clear_thread_flag(TIF_NOTIFY_RESUME);
- /*
- * This barrier pairs with task_work_add()->set_notify_resume() after
- * hlist_add_head(task->task_works);
- */
- smp_mb__after_atomic();
- if (unlikely(task_work_pending(current)))
- task_work_run();
- #ifdef CONFIG_KEYS_REQUEST_CACHE
- if (unlikely(current->cached_requested_key)) {
- key_put(current->cached_requested_key);
- current->cached_requested_key = NULL;
- }
- #endif
- mem_cgroup_handle_over_high(GFP_KERNEL);
- blkcg_maybe_throttle_current();
- rseq_handle_notify_resume(NULL, regs);
- }
- #endif /* LINUX_RESUME_USER_MODE_H */
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