From 9a4ffdf55811ff3382cdf44459ec17521bd47e5e Mon Sep 17 00:00:00 2001 From: Chao Yu Date: Fri, 29 Sep 2017 13:59:35 +0800 Subject: [PATCH] f2fs: obsolete ALLOC_NID_LIST list As Fan Li reported, there is no user traversing nid_list[ALLOC_NID_LIST] which is used for tracking preallocated nids. Let's drop it, and only track preallocated nids in free_nid_root radix-tree. Reported-by: Fan Li Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim --- fs/f2fs/debug.c | 8 ++-- fs/f2fs/f2fs.h | 15 ++++--- fs/f2fs/node.c | 97 ++++++++++++++++++++++------------------------ fs/f2fs/node.h | 15 ++----- fs/f2fs/shrinker.c | 2 +- 5 files changed, 64 insertions(+), 73 deletions(-) diff --git a/fs/f2fs/debug.c b/fs/f2fs/debug.c index 00c1d4a9f356..14095fbb4039 100644 --- a/fs/f2fs/debug.c +++ b/fs/f2fs/debug.c @@ -98,9 +98,9 @@ static void update_general_status(struct f2fs_sb_info *sbi) si->dirty_nats = NM_I(sbi)->dirty_nat_cnt; si->sits = MAIN_SEGS(sbi); si->dirty_sits = SIT_I(sbi)->dirty_sentries; - si->free_nids = NM_I(sbi)->nid_cnt[FREE_NID_LIST]; + si->free_nids = NM_I(sbi)->nid_cnt[FREE_NID]; si->avail_nids = NM_I(sbi)->available_nids; - si->alloc_nids = NM_I(sbi)->nid_cnt[ALLOC_NID_LIST]; + si->alloc_nids = NM_I(sbi)->nid_cnt[PREALLOC_NID]; si->bg_gc = sbi->bg_gc; si->util_free = (int)(free_user_blocks(sbi) >> sbi->log_blocks_per_seg) * 100 / (int)(sbi->user_block_count >> sbi->log_blocks_per_seg) @@ -233,8 +233,8 @@ get_cache: } /* free nids */ - si->cache_mem += (NM_I(sbi)->nid_cnt[FREE_NID_LIST] + - NM_I(sbi)->nid_cnt[ALLOC_NID_LIST]) * + si->cache_mem += (NM_I(sbi)->nid_cnt[FREE_NID] + + NM_I(sbi)->nid_cnt[PREALLOC_NID]) * sizeof(struct free_nid); si->cache_mem += NM_I(sbi)->nat_cnt * sizeof(struct nat_entry); si->cache_mem += NM_I(sbi)->dirty_nat_cnt * diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h index 91edbf9605c3..67944f25276f 100644 --- a/fs/f2fs/f2fs.h +++ b/fs/f2fs/f2fs.h @@ -666,10 +666,13 @@ static inline void __try_update_largest_extent(struct inode *inode, } } -enum nid_list { - FREE_NID_LIST, - ALLOC_NID_LIST, - MAX_NID_LIST, +/* + * For free nid management + */ +enum nid_state { + FREE_NID, /* newly added to free nid list */ + PREALLOC_NID, /* it is preallocated */ + MAX_NID_STATE, }; struct f2fs_nm_info { @@ -692,8 +695,8 @@ struct f2fs_nm_info { /* free node ids management */ struct radix_tree_root free_nid_root;/* root of the free_nid cache */ - struct list_head nid_list[MAX_NID_LIST];/* lists for free nids */ - unsigned int nid_cnt[MAX_NID_LIST]; /* the number of free node id */ + struct list_head free_nid_list; /* list for free nids excluding preallocated nids */ + unsigned int nid_cnt[MAX_NID_STATE]; /* the number of free node id */ spinlock_t nid_list_lock; /* protect nid lists ops */ struct mutex build_lock; /* lock for build free nids */ unsigned char (*free_nid_bitmap)[NAT_ENTRY_BITMAP_SIZE]; diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c index 33dd47f7136a..d187aa44a4ed 100644 --- a/fs/f2fs/node.c +++ b/fs/f2fs/node.c @@ -46,7 +46,7 @@ bool available_free_memory(struct f2fs_sb_info *sbi, int type) * give 25%, 25%, 50%, 50%, 50% memory for each components respectively */ if (type == FREE_NIDS) { - mem_size = (nm_i->nid_cnt[FREE_NID_LIST] * + mem_size = (nm_i->nid_cnt[FREE_NID] * sizeof(struct free_nid)) >> PAGE_SHIFT; res = mem_size < ((avail_ram * nm_i->ram_thresh / 100) >> 2); } else if (type == NAT_ENTRIES) { @@ -1757,8 +1757,8 @@ static struct free_nid *__lookup_free_nid_list(struct f2fs_nm_info *nm_i, return radix_tree_lookup(&nm_i->free_nid_root, n); } -static int __insert_nid_to_list(struct f2fs_sb_info *sbi, - struct free_nid *i, enum nid_list list, bool new) +static int __insert_free_nid(struct f2fs_sb_info *sbi, + struct free_nid *i, enum nid_state state, bool new) { struct f2fs_nm_info *nm_i = NM_I(sbi); @@ -1768,22 +1768,22 @@ static int __insert_nid_to_list(struct f2fs_sb_info *sbi, return err; } - f2fs_bug_on(sbi, list == FREE_NID_LIST ? i->state != NID_NEW : - i->state != NID_ALLOC); - nm_i->nid_cnt[list]++; - list_add_tail(&i->list, &nm_i->nid_list[list]); + f2fs_bug_on(sbi, state != i->state); + nm_i->nid_cnt[state]++; + if (state == FREE_NID) + list_add_tail(&i->list, &nm_i->free_nid_list); return 0; } -static void __remove_nid_from_list(struct f2fs_sb_info *sbi, - struct free_nid *i, enum nid_list list, bool reuse) +static void __remove_free_nid(struct f2fs_sb_info *sbi, + struct free_nid *i, enum nid_state state, bool reuse) { struct f2fs_nm_info *nm_i = NM_I(sbi); - f2fs_bug_on(sbi, list == FREE_NID_LIST ? i->state != NID_NEW : - i->state != NID_ALLOC); - nm_i->nid_cnt[list]--; - list_del(&i->list); + f2fs_bug_on(sbi, state != i->state); + nm_i->nid_cnt[state]--; + if (state == FREE_NID) + list_del(&i->list); if (!reuse) radix_tree_delete(&nm_i->free_nid_root, i->nid); } @@ -1803,7 +1803,7 @@ static bool add_free_nid(struct f2fs_sb_info *sbi, nid_t nid, bool build) i = f2fs_kmem_cache_alloc(free_nid_slab, GFP_NOFS); i->nid = nid; - i->state = NID_NEW; + i->state = FREE_NID; if (radix_tree_preload(GFP_NOFS)) goto err; @@ -1816,7 +1816,7 @@ static bool add_free_nid(struct f2fs_sb_info *sbi, nid_t nid, bool build) * - f2fs_create * - f2fs_new_inode * - alloc_nid - * - __insert_nid_to_list(ALLOC_NID_LIST) + * - __insert_nid_to_list(PREALLOC_NID) * - f2fs_balance_fs_bg * - build_free_nids * - __build_free_nids @@ -1829,8 +1829,8 @@ static bool add_free_nid(struct f2fs_sb_info *sbi, nid_t nid, bool build) * - new_node_page * - set_node_addr * - alloc_nid_done - * - __remove_nid_from_list(ALLOC_NID_LIST) - * - __insert_nid_to_list(FREE_NID_LIST) + * - __remove_nid_from_list(PREALLOC_NID) + * - __insert_nid_to_list(FREE_NID) */ ne = __lookup_nat_cache(nm_i, nid); if (ne && (!get_nat_flag(ne, IS_CHECKPOINTED) || @@ -1839,13 +1839,13 @@ static bool add_free_nid(struct f2fs_sb_info *sbi, nid_t nid, bool build) e = __lookup_free_nid_list(nm_i, nid); if (e) { - if (e->state == NID_NEW) + if (e->state == FREE_NID) ret = true; goto err_out; } } ret = true; - err = __insert_nid_to_list(sbi, i, FREE_NID_LIST, true); + err = __insert_free_nid(sbi, i, FREE_NID, true); err_out: spin_unlock(&nm_i->nid_list_lock); radix_tree_preload_end(); @@ -1863,8 +1863,8 @@ static void remove_free_nid(struct f2fs_sb_info *sbi, nid_t nid) spin_lock(&nm_i->nid_list_lock); i = __lookup_free_nid_list(nm_i, nid); - if (i && i->state == NID_NEW) { - __remove_nid_from_list(sbi, i, FREE_NID_LIST, false); + if (i && i->state == FREE_NID) { + __remove_free_nid(sbi, i, FREE_NID, false); need_free = true; } spin_unlock(&nm_i->nid_list_lock); @@ -1949,7 +1949,7 @@ static void scan_free_nid_bits(struct f2fs_sb_info *sbi) nid = i * NAT_ENTRY_PER_BLOCK + idx; add_free_nid(sbi, nid, true); - if (nm_i->nid_cnt[FREE_NID_LIST] >= MAX_FREE_NIDS) + if (nm_i->nid_cnt[FREE_NID] >= MAX_FREE_NIDS) goto out; } } @@ -1982,7 +1982,7 @@ static void __build_free_nids(struct f2fs_sb_info *sbi, bool sync, bool mount) nid = 0; /* Enough entries */ - if (nm_i->nid_cnt[FREE_NID_LIST] >= NAT_ENTRY_PER_BLOCK) + if (nm_i->nid_cnt[FREE_NID] >= NAT_ENTRY_PER_BLOCK) return; if (!sync && !available_free_memory(sbi, FREE_NIDS)) @@ -1992,7 +1992,7 @@ static void __build_free_nids(struct f2fs_sb_info *sbi, bool sync, bool mount) /* try to find free nids in free_nid_bitmap */ scan_free_nid_bits(sbi); - if (nm_i->nid_cnt[FREE_NID_LIST]) + if (nm_i->nid_cnt[FREE_NID]) return; } @@ -2069,15 +2069,15 @@ retry: } /* We should not use stale free nids created by build_free_nids */ - if (nm_i->nid_cnt[FREE_NID_LIST] && !on_build_free_nids(nm_i)) { - f2fs_bug_on(sbi, list_empty(&nm_i->nid_list[FREE_NID_LIST])); - i = list_first_entry(&nm_i->nid_list[FREE_NID_LIST], + if (nm_i->nid_cnt[FREE_NID] && !on_build_free_nids(nm_i)) { + f2fs_bug_on(sbi, list_empty(&nm_i->free_nid_list)); + i = list_first_entry(&nm_i->free_nid_list, struct free_nid, list); *nid = i->nid; - __remove_nid_from_list(sbi, i, FREE_NID_LIST, true); - i->state = NID_ALLOC; - __insert_nid_to_list(sbi, i, ALLOC_NID_LIST, false); + __remove_free_nid(sbi, i, FREE_NID, true); + i->state = PREALLOC_NID; + __insert_free_nid(sbi, i, PREALLOC_NID, false); nm_i->available_nids--; update_free_nid_bitmap(sbi, *nid, false, false); @@ -2103,7 +2103,7 @@ void alloc_nid_done(struct f2fs_sb_info *sbi, nid_t nid) spin_lock(&nm_i->nid_list_lock); i = __lookup_free_nid_list(nm_i, nid); f2fs_bug_on(sbi, !i); - __remove_nid_from_list(sbi, i, ALLOC_NID_LIST, false); + __remove_free_nid(sbi, i, PREALLOC_NID, false); spin_unlock(&nm_i->nid_list_lock); kmem_cache_free(free_nid_slab, i); @@ -2126,12 +2126,12 @@ void alloc_nid_failed(struct f2fs_sb_info *sbi, nid_t nid) f2fs_bug_on(sbi, !i); if (!available_free_memory(sbi, FREE_NIDS)) { - __remove_nid_from_list(sbi, i, ALLOC_NID_LIST, false); + __remove_free_nid(sbi, i, PREALLOC_NID, false); need_free = true; } else { - __remove_nid_from_list(sbi, i, ALLOC_NID_LIST, true); - i->state = NID_NEW; - __insert_nid_to_list(sbi, i, FREE_NID_LIST, false); + __remove_free_nid(sbi, i, PREALLOC_NID, true); + i->state = FREE_NID; + __insert_free_nid(sbi, i, FREE_NID, false); } nm_i->available_nids++; @@ -2150,20 +2150,19 @@ int try_to_free_nids(struct f2fs_sb_info *sbi, int nr_shrink) struct free_nid *i, *next; int nr = nr_shrink; - if (nm_i->nid_cnt[FREE_NID_LIST] <= MAX_FREE_NIDS) + if (nm_i->nid_cnt[FREE_NID] <= MAX_FREE_NIDS) return 0; if (!mutex_trylock(&nm_i->build_lock)) return 0; spin_lock(&nm_i->nid_list_lock); - list_for_each_entry_safe(i, next, &nm_i->nid_list[FREE_NID_LIST], - list) { + list_for_each_entry_safe(i, next, &nm_i->free_nid_list, list) { if (nr_shrink <= 0 || - nm_i->nid_cnt[FREE_NID_LIST] <= MAX_FREE_NIDS) + nm_i->nid_cnt[FREE_NID] <= MAX_FREE_NIDS) break; - __remove_nid_from_list(sbi, i, FREE_NID_LIST, false); + __remove_free_nid(sbi, i, FREE_NID, false); kmem_cache_free(free_nid_slab, i); nr_shrink--; } @@ -2635,16 +2634,15 @@ static int init_node_manager(struct f2fs_sb_info *sbi) /* not used nids: 0, node, meta, (and root counted as valid node) */ nm_i->available_nids = nm_i->max_nid - sbi->total_valid_node_count - F2FS_RESERVED_NODE_NUM; - nm_i->nid_cnt[FREE_NID_LIST] = 0; - nm_i->nid_cnt[ALLOC_NID_LIST] = 0; + nm_i->nid_cnt[FREE_NID] = 0; + nm_i->nid_cnt[PREALLOC_NID] = 0; nm_i->nat_cnt = 0; nm_i->ram_thresh = DEF_RAM_THRESHOLD; nm_i->ra_nid_pages = DEF_RA_NID_PAGES; nm_i->dirty_nats_ratio = DEF_DIRTY_NAT_RATIO_THRESHOLD; INIT_RADIX_TREE(&nm_i->free_nid_root, GFP_ATOMIC); - INIT_LIST_HEAD(&nm_i->nid_list[FREE_NID_LIST]); - INIT_LIST_HEAD(&nm_i->nid_list[ALLOC_NID_LIST]); + INIT_LIST_HEAD(&nm_i->free_nid_list); INIT_RADIX_TREE(&nm_i->nat_root, GFP_NOIO); INIT_RADIX_TREE(&nm_i->nat_set_root, GFP_NOIO); INIT_LIST_HEAD(&nm_i->nat_entries); @@ -2736,16 +2734,15 @@ void destroy_node_manager(struct f2fs_sb_info *sbi) /* destroy free nid list */ spin_lock(&nm_i->nid_list_lock); - list_for_each_entry_safe(i, next_i, &nm_i->nid_list[FREE_NID_LIST], - list) { - __remove_nid_from_list(sbi, i, FREE_NID_LIST, false); + list_for_each_entry_safe(i, next_i, &nm_i->free_nid_list, list) { + __remove_free_nid(sbi, i, FREE_NID, false); spin_unlock(&nm_i->nid_list_lock); kmem_cache_free(free_nid_slab, i); spin_lock(&nm_i->nid_list_lock); } - f2fs_bug_on(sbi, nm_i->nid_cnt[FREE_NID_LIST]); - f2fs_bug_on(sbi, nm_i->nid_cnt[ALLOC_NID_LIST]); - f2fs_bug_on(sbi, !list_empty(&nm_i->nid_list[ALLOC_NID_LIST])); + f2fs_bug_on(sbi, nm_i->nid_cnt[FREE_NID]); + f2fs_bug_on(sbi, nm_i->nid_cnt[PREALLOC_NID]); + f2fs_bug_on(sbi, !list_empty(&nm_i->free_nid_list)); spin_unlock(&nm_i->nid_list_lock); /* destroy nat cache */ diff --git a/fs/f2fs/node.h b/fs/f2fs/node.h index bb53e9955ff2..e91b08b4a51a 100644 --- a/fs/f2fs/node.h +++ b/fs/f2fs/node.h @@ -150,18 +150,10 @@ struct nat_entry_set { unsigned int entry_cnt; /* the # of nat entries in set */ }; -/* - * For free nid mangement - */ -enum nid_state { - NID_NEW, /* newly added to free nid list */ - NID_ALLOC /* it is allocated */ -}; - struct free_nid { struct list_head list; /* for free node id list */ nid_t nid; /* node id */ - int state; /* in use or not: NID_NEW or NID_ALLOC */ + int state; /* in use or not: FREE_NID or PREALLOC_NID */ }; static inline void next_free_nid(struct f2fs_sb_info *sbi, nid_t *nid) @@ -170,12 +162,11 @@ static inline void next_free_nid(struct f2fs_sb_info *sbi, nid_t *nid) struct free_nid *fnid; spin_lock(&nm_i->nid_list_lock); - if (nm_i->nid_cnt[FREE_NID_LIST] <= 0) { + if (nm_i->nid_cnt[FREE_NID] <= 0) { spin_unlock(&nm_i->nid_list_lock); return; } - fnid = list_first_entry(&nm_i->nid_list[FREE_NID_LIST], - struct free_nid, list); + fnid = list_first_entry(&nm_i->free_nid_list, struct free_nid, list); *nid = fnid->nid; spin_unlock(&nm_i->nid_list_lock); } diff --git a/fs/f2fs/shrinker.c b/fs/f2fs/shrinker.c index 5c60fc28ec75..0b5664a1a6cc 100644 --- a/fs/f2fs/shrinker.c +++ b/fs/f2fs/shrinker.c @@ -28,7 +28,7 @@ static unsigned long __count_nat_entries(struct f2fs_sb_info *sbi) static unsigned long __count_free_nids(struct f2fs_sb_info *sbi) { - long count = NM_I(sbi)->nid_cnt[FREE_NID_LIST] - MAX_FREE_NIDS; + long count = NM_I(sbi)->nid_cnt[FREE_NID] - MAX_FREE_NIDS; return count > 0 ? count : 0; }