Server : nginx/1.18.0 System : Linux localhost 6.14.3-x86_64-linode168 #1 SMP PREEMPT_DYNAMIC Mon Apr 21 19:47:55 EDT 2025 x86_64 User : www-data ( 33) PHP Version : 8.0.16 Disable Function : pcntl_alarm,pcntl_fork,pcntl_waitpid,pcntl_wait,pcntl_wifexited,pcntl_wifstopped,pcntl_wifsignaled,pcntl_wifcontinued,pcntl_wexitstatus,pcntl_wtermsig,pcntl_wstopsig,pcntl_signal,pcntl_signal_get_handler,pcntl_signal_dispatch,pcntl_get_last_error,pcntl_strerror,pcntl_sigprocmask,pcntl_sigwaitinfo,pcntl_sigtimedwait,pcntl_exec,pcntl_getpriority,pcntl_setpriority,pcntl_async_signals,pcntl_unshare, Directory :  /usr/src/linux-headers-5.4.0-215/include/linux/

Upload File : current_dir [ Writeable ] document_root [ Writeable ]

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _LINUX_RCUWAIT_H_
#define _LINUX_RCUWAIT_H_

#include <linux/rcupdate.h>

/*
 * rcuwait provides a way of blocking and waking up a single
 * task in an rcu-safe manner.
 *
 * The only time @task is non-nil is when a user is blocked (or
 * checking if it needs to) on a condition, and reset as soon as we
 * know that the condition has succeeded and are awoken.
 */
struct rcuwait {
	struct task_struct __rcu *task;
};

#define __RCUWAIT_INITIALIZER(name)		\
	{ .task = NULL, }

static inline void rcuwait_init(struct rcuwait *w)
{
	w->task = NULL;
}

extern void rcuwait_wake_up(struct rcuwait *w);

/*
 * The caller is responsible for locking around rcuwait_wait_event(),
 * such that writes to @task are properly serialized.
 */
#define rcuwait_wait_event(w, condition)				\
({									\
	rcu_assign_pointer((w)->task, current);				\
	for (;;) {							\
		/*							\
		 * Implicit barrier (A) pairs with (B) in		\
		 * rcuwait_wake_up().					\
		 */							\
		set_current_state(TASK_UNINTERRUPTIBLE);		\
		if (condition)						\
			break;						\
									\
		schedule();						\
	}								\
									\
	WRITE_ONCE((w)->task, NULL);					\
	__set_current_state(TASK_RUNNING);				\
})

#endif /* _LINUX_RCUWAIT_H_ */