mirror of
https://github.com/torvalds/linux.git
synced 2024-12-05 02:23:16 +00:00
02110a4fd5
This patch makes sure it returns a positive value instead of a probable casted negative value as shrink count. Signed-off-by: Chao Yu <yuchao0@huawei.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
144 lines
3.3 KiB
C
144 lines
3.3 KiB
C
/*
|
|
* 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);
|
|
}
|