// SPDX-License-Identifier: GPL-2.0-only
/*
 *  linux/mm/oom_kill.c
 *
 *  Copyright (C)  1998,2000  Rik van Riel
 *	Thanks go out to Claus Fischer for some serious inspiration and
 *	for goading me into coding this file...
 *  Copyright (C)  2010  Google, Inc.
 *	Rewritten by David Rientjes
 *
 *  The routines in this file are used to kill a process when
 *  we're seriously out of memory. This gets called from __alloc_pages()
 *  in mm/page_alloc.c when we really run out of memory.
 *
 *  Since we won't call these routines often (on a well-configured
 *  machine) this file will double as a 'coding guide' and a signpost
 *  for newbie kernel hackers. It features several pointers to major
 *  kernel subsystems and hints as to where to find out what things do.
 */

/*
 * Official Linux v6.18: mm/oom_kill.c
 * https://github.com/torvalds/linux/blob/v6.18/mm/oom_kill.c#L649
 * Complete upstream scope, not an elided book-code reconstruction.
 * See GPL-2.0.txt. Not a standalone translation unit.
 */

static int oom_reaper(void *unused)
{
	set_freezable();

	while (true) {
		struct task_struct *tsk = NULL;

		wait_event_freezable(oom_reaper_wait, oom_reaper_list != NULL);
		spin_lock_irq(&oom_reaper_lock);
		if (oom_reaper_list != NULL) {
			tsk = oom_reaper_list;
			oom_reaper_list = tsk->oom_reaper_list;
		}
		spin_unlock_irq(&oom_reaper_lock);

		if (tsk)
			oom_reap_task(tsk);
	}

	return 0;
}