/* SPDX-License-Identifier: GPL-2.0 */
/*
* fs/f2fs/gc.h
*
* Copyright (c) 2012 Samsung Electronics Co., Ltd.
* http://www.samsung.com/
*/
#define GC_THREAD_MIN_WB_PAGES 1 /*
* a threshold to determine
* whether IO subsystem is idle
* or not
*/
#define DEF_GC_THREAD_URGENT_SLEEP_TIME 500 /* 500 ms */
#define DEF_GC_THREAD_MIN_SLEEP_TIME 30000 /* milliseconds */
#define DEF_GC_THREAD_MAX_SLEEP_TIME 60000
#define DEF_GC_THREAD_NOGC_SLEEP_TIME 300000 /* wait 5 min */
/* GC sleep parameters for zoned deivces */
#define DEF_GC_THREAD_MIN_SLEEP_TIME_ZONED 10
#define DEF_GC_THREAD_MAX_SLEEP_TIME_ZONED 20
#define DEF_GC_THREAD_NOGC_SLEEP_TIME_ZONED 60000
/* choose candidates from sections which has age of more than 7 days */
#define DEF_GC_THREAD_AGE_THRESHOLD (60 * 60 * 24 * 7)
#define DEF_GC_THREAD_CANDIDATE_RATIO 20 /* select 20% oldest sections as candidates */
#define DEF_GC_THREAD_MAX_CANDIDATE_COUNT 10 /* select at most 10 sections as candidates */
#define DEF_GC_THREAD_AGE_WEIGHT 60 /* age weight */
#define DEF_GC_THREAD_VALID_THRESH_RATIO 95 /* do not GC over 95% valid block ratio for one time GC */
#define DEFAULT_ACCURACY_CLASS 10000 /* accuracy class */
#define LIMIT_INVALID_BLOCK 40 /* percentage over total user space */
#define LIMIT_FREE_BLOCK 40 /* percentage over invalid + free space */
#define LIMIT_NO_ZONED_GC 60 /* percentage over total user space of no gc for zoned devices */
#define LIMIT_BOOST_ZONED_GC 25 /* percentage over total user space of boosted gc for zoned devices */
#define DEF_MIGRATION_WINDOW_GRANULARITY_ZONED 3
#define BOOST_GC_MULTIPLE 5
#define DEF_GC_FAILED_PINNED_FILES 2048
#define MAX_GC_FAILED_PINNED_FILES USHRT_MAX
/* Search max. number of dirty segments to select a victim segment */
#define DEF_MAX_VICTIM_SEARCH 4096 /* covers 8GB */
#define NR_GC_CHECKPOINT_SECS (3) /* data/node/dentry sections */
struct f2fs_gc_kthread {
struct task_struct *f2fs_gc_task;
wait_queue_head_t gc_wait_queue_head;
/* for gc sleep time */
unsigned int urgent_sleep_time;
unsigned int min_sleep_time;
unsigned int max_sleep_time;
unsigned int no_gc_sleep_time;
/* for changing gc mode */
bool gc_wake;
/* for GC_MERGE mount option */
wait_queue_head_t fggc_wq; /*
* caller of f2fs_balance_fs()
* will wait on this wait queue.
*/
/* for gc control for zoned devices */
unsigned int no_zoned_gc_percent;
unsigned int boost_zoned_gc_percent;
unsigned int valid_thresh_ratio;
};
struct gc_inode_list {
struct list_head ilist;
struct radix_tree_root iroot;
};
struct victim_entry {
struct rb_node rb_node; /* rb node located in rb-tree */
unsigned long long mtime; /* mtime of section */
unsigned int segno; /* segment No. */
struct list_head list;
};
/*
* inline functions
*/
/*
* On a Zoned device zone-capacity can be less than zone-size and if
* zone-capacity is not aligned to f2fs segment size(2MB), then the segment
* starting just before zone-capacity has some blocks spanning across the
* zone-capacity, these blocks are not usable.
* Such spanning segments can be in free list so calculate the sum of usable
* blocks in currently free segments including normal and spanning segments.
*/
static inline block_t free_segs_blk_count_zoned(struct f2fs_sb_info *sbi)
{
block_t free_seg_blks = 0;
struct free_segmap_info *free_i = FREE_I(sbi);
int j;
spin_lock(&free_i->segmap_lock);
for (j = 0; j < MAIN_SEGS(sbi); j++)
if (!test_bit(j, free_i->free_segmap))
free_seg_blks += f2fs_usable_blks_in_seg(sbi, j);
spin_unlock(&free_i->segmap_lock);
return free_seg_blks;
}
static inline block_t free_segs_blk_count(struct f2fs_sb_info *sbi)
{
if (f2fs_sb_has_blkzoned(sbi))
return free_segs_blk_count_zoned(sbi);
return SEGS_TO_BLKS(sbi, free_segments(sbi));
}
static inline block_t free_user_blocks(struct f2fs_sb_info *sbi)
{
block_t free_blks, ovp_blks;
free_blks = free_segs_blk_count(sbi);
ovp_blks = SEGS_TO_BLKS(sbi, overprovision_segments(sbi));
if (free_blks < ovp_blks)
return 0;
return free_blks - ovp_blks;
}
static inline block_t limit_invalid_user_blocks(block_t user_block_count)
{
return (long)(user_block_count * LIMIT_INVALID_BLOCK) / 100;
}
static inline block_t limit_free_user_blocks(block_t reclaimable_user_blocks)
{
return (long)(reclaimable_user_blocks * LIMIT_FREE_BLOCK) / 100;
}
static inline void increase_sleep_time(struct f2fs_gc_kthread *gc_th,
unsigned int *wait)
{
unsigned int min_time = gc_th->min_sleep_time;
unsigned int max_time = gc_th->max_sleep_time;
if (*wait == gc_th->no_gc_sleep_time)
return;
if ((long long)*wait + (long long)min_time > (long long)max_time)
*wait = max_time;
else
*wait += min_time;
}
static inline void decrease_sleep_time(struct f2fs_gc_kthread *gc_th,
unsigned int *wait)
{
unsigned int min_time = gc_th->min_sleep_time;
if (*wait == gc_th->no_gc_sleep_time)
*wait = gc_th->max_sleep_time;
if ((long long)*wait - (long long)min_time < (long long)min_time)
*wait = min_time;
else
*wait -= min_time;
}
static inline bool has_enough_free_blocks(struct f2fs_sb_info *sbi,
unsigned int limit_perc)
{
return free_sections(sbi) > ((sbi->total_sections * limit_perc) / 100);
}
static inline bool has_enough_invalid_blocks(struct f2fs_sb_info *sbi)
{
block_t user_block_count = sbi->user_block_count;
block_t invalid_user_blocks = user_block_count -
written_block_count(sbi);
/*
* Background GC is triggered with the following conditions.
* 1. There are a number of invalid blocks.
* 2. There is not enough free space.
*/
return (invalid_user_blocks >
limit_invalid_user_blocks(user_block_count) &&
free_user_blocks(sbi) <
limit_free_user_blocks(invalid_user_blocks));
}
static inline bool need_to_boost_gc(struct f2fs_sb_info *sbi)
{
if (f2fs_sb_has_blkzoned(sbi))
return !has_enough_free_blocks(sbi, LIMIT_BOOST_ZONED_GC);
return has_enough_invalid_blocks(sbi);
}