/*
 * 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>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */
#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_LIST] - 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);

		/* shrink 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 += try_to_free_nats(sbi, nr - freed);

		/* shrink free nids cache entries */
		if (freed < nr)
			freed += 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(&sbi->s_list);
	spin_unlock(&f2fs_list_lock);
}
t/Makefile?h=nds-private-remove&amp;id=10435c1192d06bdb0bac7666452d8219d7e7c477'>Makefile</a></div><div class='content'><div class='cgit-panel'><b>diff options</b><form method='get'><input type='hidden' name='h' value='nds-private-remove'/><input type='hidden' name='id' value='10435c1192d06bdb0bac7666452d8219d7e7c477'/><table><tr><td colspan='2'/></tr><tr><td class='label'>context:</td><td class='ctrl'><select name='context' onchange='this.form.submit();'><option value='1'>1</option><option value='2'>2</option><option value='3' selected='selected'>3</option><option value='4'>4</option><option value='5'>5</option><option value='6'>6</option><option value='7'>7</option><option value='8'>8</option><option value='9'>9</option><option value='10'>10</option><option value='15'>15</option><option value='20'>20</option><option value='25'>25</option><option value='30'>30</option><option value='35'>35</option><option value='40'>40</option></select></td></tr><tr><td class='label'>space:</td><td class='ctrl'><select name='ignorews' onchange='this.form.submit();'><option value='0' selected='selected'>include</option><option value='1'>ignore</option></select></td></tr><tr><td class='label'>mode:</td><td class='ctrl'><select name='dt' onchange='this.form.submit();'><option value='0' selected='selected'>unified</option><option value='1'>ssdiff</option><option value='2'>stat only</option></select></td></tr><tr><td/><td class='ctrl'><noscript><input type='submit' value='reload'/></noscript></td></tr></table></form></div><table summary='commit info' class='commit-info'>
<tr><th>author</th><td>Feng &lt;fgao@ikuai8.com&gt;</td><td class='right'>2017-01-20 21:40:43 +0800</td></tr>
<tr><th>committer</th><td>Pablo Neira Ayuso &lt;pablo@netfilter.org&gt;</td><td class='right'>2017-02-02 14:30:19 +0100</td></tr>
<tr><th>commit</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/net/decnet/Makefile?h=nds-private-remove&amp;id=10435c1192d06bdb0bac7666452d8219d7e7c477'>10435c1192d06bdb0bac7666452d8219d7e7c477</a> (<a href='/cgit.cgi/linux/net-next.git/patch/net/decnet/Makefile?id=10435c1192d06bdb0bac7666452d8219d7e7c477'>patch</a>)</td></tr>
<tr><th>tree</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/tree/?h=nds-private-remove&amp;id=10435c1192d06bdb0bac7666452d8219d7e7c477'>93b76419142fe17b1d162d062c663297a3e8a965</a> /<a href='/cgit.cgi/linux/net-next.git/tree/net/decnet/Makefile?h=nds-private-remove&amp;id=10435c1192d06bdb0bac7666452d8219d7e7c477'>net/decnet/Makefile</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/net/decnet/Makefile?h=nds-private-remove&amp;id=1a28ad74ebd8f9d3c7eae0d781f72a6d30545e17'>1a28ad74ebd8f9d3c7eae0d781f72a6d30545e17</a> (<a href='/cgit.cgi/linux/net-next.git/diff/net/decnet/Makefile?h=nds-private-remove&amp;id=10435c1192d06bdb0bac7666452d8219d7e7c477&amp;id2=1a28ad74ebd8f9d3c7eae0d781f72a6d30545e17'>diff</a>)</td></tr></table>
<div class='commit-subject'>netfilter: nf_tables: Eliminate duplicated code in nf_tables_table_enable()</div><div class='commit-msg'>If something fails in nf_tables_table_enable(), it unregisters the
chains. But the rollback code is the same as nf_tables_table_disable()
almostly, except there is one counter check.  Now create one wrapper
function to eliminate the duplicated codes.

Signed-off-by: Feng &lt;fgao@ikuai8.com&gt;
Signed-off-by: Pablo Neira Ayuso &lt;pablo@netfilter.org&gt;
</div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?h=nds-private-remove&amp;id=10435c1192d06bdb0bac7666452d8219d7e7c477'>Diffstat</a> (limited to 'net/decnet/Makefile')</div><table summary='diffstat' class='diffstat'>