[linux-block.git] / fs / f2fs / shrinker.c

// SPDX-License-Identifier: GPL-2.0
/*
 * f2fs shrinker support
 *   the basic infra was copied from fs/ubifs/shrinker.c
 *
 * Copyright (c) 2015 Motorola Mobility
 * Copyright (c) 2015 Jaegeuk Kim <jaegeuk@kernel.org>
 */
#include <linux/fs.h>
#include <linux/f2fs_fs.h>

#include "f2fs.h"
#include "node.h"

static LIST_HEAD(f2fs_list);
static DEFINE_SPINLOCK(f2fs_list_lock);
static unsigned int shrinker_run_no;

static unsigned long __count_nat_entries(struct f2fs_sb_info *sbi)
{
	long count = NM_I(sbi)->nat_cnt - NM_I(sbi)->dirty_nat_cnt;

	return count > 0 ? count : 0;
}

static unsigned long __count_free_nids(struct f2fs_sb_info *sbi)
{
	long count = NM_I(sbi)->nid_cnt[FREE_NID] - MAX_FREE_NIDS;

	return count > 0 ? count : 0;
}

static unsigned long __count_extent_cache(struct f2fs_sb_info *sbi)
{
	return atomic_read(&sbi->total_zombie_tree) +
				atomic_read(&sbi->total_ext_node);
}

unsigned long f2fs_shrink_count(struct shrinker *shrink,
				struct shrink_control *sc)
{
	struct f2fs_sb_info *sbi;
	struct list_head *p;
	unsigned long count = 0;

	spin_lock(&f2fs_list_lock);
	p = f2fs_list.next;
	while (p != &f2fs_list) {
		sbi = list_entry(p, struct f2fs_sb_info, s_list);

		/* stop f2fs_put_super */
		if (!mutex_trylock(&sbi->umount_mutex)) {
			p = p->next;
			continue;
		}
		spin_unlock(&f2fs_list_lock);

		/* count extent cache entries */
		count += __count_extent_cache(sbi);

		/* count clean nat cache entries */
		count += __count_nat_entries(sbi);

		/* count free nids cache entries */
		count += __count_free_nids(sbi);

		spin_lock(&f2fs_list_lock);
		p = p->next;
		mutex_unlock(&sbi->umount_mutex);
	}
	spin_unlock(&f2fs_list_lock);
	return count;
}

unsigned long f2fs_shrink_scan(struct shrinker *shrink,
				struct shrink_control *sc)
{
	unsigned long nr = sc->nr_to_scan;
	struct f2fs_sb_info *sbi;
	struct list_head *p;
	unsigned int run_no;
	unsigned long freed = 0;

	spin_lock(&f2fs_list_lock);
	do {
		run_no = ++shrinker_run_no;
	} while (run_no == 0);
	p = f2fs_list.next;
	while (p != &f2fs_list) {
		sbi = list_entry(p, struct f2fs_sb_info, s_list);

		if (sbi->shrinker_run_no == run_no)
			break;

		/* stop f2fs_put_super */
		if (!mutex_trylock(&sbi->umount_mutex)) {
			p = p->next;
			continue;
		}
		spin_unlock(&f2fs_list_lock);

		sbi->shrinker_run_no = run_no;

		/* shrink extent cache entries */
		freed += f2fs_shrink_extent_tree(sbi, nr >> 1);

		/* shrink clean nat cache entries */
		if (freed < nr)
			freed += f2fs_try_to_free_nats(sbi, nr - freed);

		/* shrink free nids cache entries */
		if (freed < nr)
			freed += f2fs_try_to_free_nids(sbi, nr - freed);

		spin_lock(&f2fs_list_lock);
		p = p->next;
		list_move_tail(&sbi->s_list, &f2fs_list);
		mutex_unlock(&sbi->umount_mutex);
		if (freed >= nr)
			break;
	}
	spin_unlock(&f2fs_list_lock);
	return freed;
}

void f2fs_join_shrinker(struct f2fs_sb_info *sbi)
{
	spin_lock(&f2fs_list_lock);
	list_add_tail(&sbi->s_list, &f2fs_list);
	spin_unlock(&f2fs_list_lock);
}

void f2fs_leave_shrinker(struct f2fs_sb_info *sbi)
{
	f2fs_shrink_extent_tree(sbi, __count_extent_cache(sbi));

	spin_lock(&f2fs_list_lock);
	list_del_init(&sbi->s_list);
	spin_unlock(&f2fs_list_lock);
}
Commit	Line	Data
7c1a000d	1	// SPDX-License-Identifier: GPL-2.0
2658e50d JK	2	/*
	3	* f2fs shrinker support
	4	* the basic infra was copied from fs/ubifs/shrinker.c
	5	*
	6	* Copyright (c) 2015 Motorola Mobility
	7	* Copyright (c) 2015 Jaegeuk Kim <jaegeuk@kernel.org>
2658e50d JK	8	*/
	9	#include <linux/fs.h>
	10	#include <linux/f2fs_fs.h>
	11
	12	#include "f2fs.h"
ad4edb83	13	#include "node.h"
2658e50d JK	14
	15	static LIST_HEAD(f2fs_list);
	16	static DEFINE_SPINLOCK(f2fs_list_lock);
	17	static unsigned int shrinker_run_no;
	18
1b38dc8e JK	19	static unsigned long __count_nat_entries(struct f2fs_sb_info *sbi)
1b38dc8e JK	20	{
02110a4f CY	21	long count = NM_I(sbi)->nat_cnt - NM_I(sbi)->dirty_nat_cnt;
	22
	23	return count > 0 ? count : 0;
1b38dc8e JK	24	}
1b38dc8e JK	25
31696580 CY	26	static unsigned long __count_free_nids(struct f2fs_sb_info *sbi)
31696580 CY	27	{
9a4ffdf5	28	long count = NM_I(sbi)->nid_cnt[FREE_NID] - MAX_FREE_NIDS;
02110a4f CY	29
02110a4f CY	30	return count > 0 ? count : 0;
31696580 CY	31	}
31696580 CY	32
554df79e JK	33	static unsigned long __count_extent_cache(struct f2fs_sb_info *sbi)
554df79e JK	34	{
74fd8d99	35	return atomic_read(&sbi->total_zombie_tree) +
7441ccef	36	atomic_read(&sbi->total_ext_node);
554df79e JK	37	}
554df79e JK	38
2658e50d JK	39	unsigned long f2fs_shrink_count(struct shrinker *shrink,
	40	struct shrink_control *sc)
	41	{
	42	struct f2fs_sb_info *sbi;
	43	struct list_head *p;
	44	unsigned long count = 0;
	45
	46	spin_lock(&f2fs_list_lock);
	47	p = f2fs_list.next;
	48	while (p != &f2fs_list) {
	49	sbi = list_entry(p, struct f2fs_sb_info, s_list);
	50
	51	/* stop f2fs_put_super */
	52	if (!mutex_trylock(&sbi->umount_mutex)) {
	53	p = p->next;
	54	continue;
	55	}
	56	spin_unlock(&f2fs_list_lock);
	57
554df79e JK	58	/* count extent cache entries */
	59	count += __count_extent_cache(sbi);
	60
7a88ddb5	61	/* count clean nat cache entries */
1b38dc8e	62	count += __count_nat_entries(sbi);
2658e50d	63
31696580 CY	64	/* count free nids cache entries */
	65	count += __count_free_nids(sbi);
	66
2658e50d JK	67	spin_lock(&f2fs_list_lock);
	68	p = p->next;
	69	mutex_unlock(&sbi->umount_mutex);
	70	}
	71	spin_unlock(&f2fs_list_lock);
	72	return count;
	73	}
	74
	75	unsigned long f2fs_shrink_scan(struct shrinker *shrink,
	76	struct shrink_control *sc)
	77	{
	78	unsigned long nr = sc->nr_to_scan;
	79	struct f2fs_sb_info *sbi;
	80	struct list_head *p;
	81	unsigned int run_no;
	82	unsigned long freed = 0;
	83
	84	spin_lock(&f2fs_list_lock);
	85	do {
	86	run_no = ++shrinker_run_no;
	87	} while (run_no == 0);
	88	p = f2fs_list.next;
	89	while (p != &f2fs_list) {
	90	sbi = list_entry(p, struct f2fs_sb_info, s_list);
	91
	92	if (sbi->shrinker_run_no == run_no)
	93	break;
	94
	95	/* stop f2fs_put_super */
	96	if (!mutex_trylock(&sbi->umount_mutex)) {
	97	p = p->next;
	98	continue;
	99	}
	100	spin_unlock(&f2fs_list_lock);
	101
	102	sbi->shrinker_run_no = run_no;
	103
554df79e JK	104	/* shrink extent cache entries */
	105	freed += f2fs_shrink_extent_tree(sbi, nr >> 1);
	106
1b38dc8e	107	/* shrink clean nat cache entries */
554df79e	108	if (freed < nr)
4d57b86d	109	freed += f2fs_try_to_free_nats(sbi, nr - freed);
2658e50d	110
31696580 CY	111	/* shrink free nids cache entries */
31696580 CY	112	if (freed < nr)
4d57b86d	113	freed += f2fs_try_to_free_nids(sbi, nr - freed);
31696580	114
2658e50d JK	115	spin_lock(&f2fs_list_lock);
	116	p = p->next;
	117	list_move_tail(&sbi->s_list, &f2fs_list);
	118	mutex_unlock(&sbi->umount_mutex);
	119	if (freed >= nr)
	120	break;
	121	}
	122	spin_unlock(&f2fs_list_lock);
	123	return freed;
	124	}
	125
	126	void f2fs_join_shrinker(struct f2fs_sb_info *sbi)
	127	{
	128	spin_lock(&f2fs_list_lock);
	129	list_add_tail(&sbi->s_list, &f2fs_list);
	130	spin_unlock(&f2fs_list_lock);
	131	}
	132
	133	void f2fs_leave_shrinker(struct f2fs_sb_info *sbi)
	134	{
3e72f721 JK	135	f2fs_shrink_extent_tree(sbi, __count_extent_cache(sbi));
3e72f721 JK	136
2658e50d	137	spin_lock(&f2fs_list_lock);
e4589fa5	138	list_del_init(&sbi->s_list);
2658e50d JK	139	spin_unlock(&f2fs_list_lock);
2658e50d JK	140	}