From 437275272f9e635673f065300e5d95226a25cb06 Mon Sep 17 00:00:00 2001 From: Jaegeuk Kim Date: Mon, 4 Feb 2013 15:11:17 +0900 Subject: f2fs: clarify and enhance the f2fs_gc flow This patch makes clearer the ambiguous f2fs_gc flow as follows. 1. Remove intermediate checkpoint condition during f2fs_gc (i.e., should_do_checkpoint() and GC_BLOCKED) 2. Remove unnecessary return values of f2fs_gc because of #1. (i.e., GC_NODE, GC_OK, etc) 3. Simplify write_checkpoint() because of #2. 4. Clarify the main f2fs_gc flow. o monitor how many freed sections during one iteration of do_garbage_collect(). o do GC more without checkpoints if we can't get enough free sections. o do checkpoint once we've got enough free sections through forground GCs. 5. Adopt thread-logging (Slack-Space-Recycle) scheme more aggressively on data log types. See. get_ssr_segement() Signed-off-by: Jaegeuk Kim --- fs/f2fs/checkpoint.c | 10 ++--- fs/f2fs/f2fs.h | 3 +- fs/f2fs/gc.c | 107 ++++++++++++++++++++------------------------------- fs/f2fs/gc.h | 16 -------- fs/f2fs/node.c | 2 +- fs/f2fs/recovery.c | 2 +- fs/f2fs/segment.c | 21 +++++++++- fs/f2fs/segment.h | 12 ++---- fs/f2fs/super.c | 4 +- 9 files changed, 72 insertions(+), 105 deletions(-) (limited to 'fs/f2fs') diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c index 2887c196b0a2..2b6fc131e2ce 100644 --- a/fs/f2fs/checkpoint.c +++ b/fs/f2fs/checkpoint.c @@ -539,7 +539,7 @@ retry: /* * Freeze all the FS-operations for checkpoint. */ -void block_operations(struct f2fs_sb_info *sbi) +static void block_operations(struct f2fs_sb_info *sbi) { int t; struct writeback_control wbc = { @@ -722,15 +722,13 @@ static void do_checkpoint(struct f2fs_sb_info *sbi, bool is_umount) /* * We guarantee that this checkpoint procedure should not fail. */ -void write_checkpoint(struct f2fs_sb_info *sbi, bool blocked, bool is_umount) +void write_checkpoint(struct f2fs_sb_info *sbi, bool is_umount) { struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi); unsigned long long ckpt_ver; - if (!blocked) { - mutex_lock(&sbi->cp_mutex); - block_operations(sbi); - } + mutex_lock(&sbi->cp_mutex); + block_operations(sbi); f2fs_submit_bio(sbi, DATA, true); f2fs_submit_bio(sbi, NODE, true); diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h index 87840bccaf21..e7e7a29767d6 100644 --- a/fs/f2fs/f2fs.h +++ b/fs/f2fs/f2fs.h @@ -969,8 +969,7 @@ int get_valid_checkpoint(struct f2fs_sb_info *); void set_dirty_dir_page(struct inode *, struct page *); void remove_dirty_dir_inode(struct inode *); void sync_dirty_dir_inodes(struct f2fs_sb_info *); -void block_operations(struct f2fs_sb_info *); -void write_checkpoint(struct f2fs_sb_info *, bool, bool); +void write_checkpoint(struct f2fs_sb_info *, bool); void init_orphan_info(struct f2fs_sb_info *); int __init create_checkpoint_caches(void); void destroy_checkpoint_caches(void); diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c index 16fdec355201..52d3a391b922 100644 --- a/fs/f2fs/gc.c +++ b/fs/f2fs/gc.c @@ -78,7 +78,8 @@ static int gc_thread_func(void *data) sbi->bg_gc++; - if (f2fs_gc(sbi) == GC_NONE) + /* if return value is not zero, no victim was selected */ + if (f2fs_gc(sbi)) wait_ms = GC_THREAD_NOGC_SLEEP_TIME; else if (wait_ms == GC_THREAD_NOGC_SLEEP_TIME) wait_ms = GC_THREAD_MAX_SLEEP_TIME; @@ -360,7 +361,7 @@ static int check_valid_map(struct f2fs_sb_info *sbi, sentry = get_seg_entry(sbi, segno); ret = f2fs_test_bit(offset, sentry->cur_valid_map); mutex_unlock(&sit_i->sentry_lock); - return ret ? GC_OK : GC_NEXT; + return ret; } /* @@ -368,7 +369,7 @@ static int check_valid_map(struct f2fs_sb_info *sbi, * On validity, copy that node with cold status, otherwise (invalid node) * ignore that. */ -static int gc_node_segment(struct f2fs_sb_info *sbi, +static void gc_node_segment(struct f2fs_sb_info *sbi, struct f2fs_summary *sum, unsigned int segno, int gc_type) { bool initial = true; @@ -380,21 +381,12 @@ next_step: for (off = 0; off < sbi->blocks_per_seg; off++, entry++) { nid_t nid = le32_to_cpu(entry->nid); struct page *node_page; - int err; - /* - * It makes sure that free segments are able to write - * all the dirty node pages before CP after this CP. - * So let's check the space of dirty node pages. - */ - if (should_do_checkpoint(sbi)) { - mutex_lock(&sbi->cp_mutex); - block_operations(sbi); - return GC_BLOCKED; - } + /* stop BG_GC if there is not enough free sections. */ + if (gc_type == BG_GC && has_not_enough_free_secs(sbi, 0)) + return; - err = check_valid_map(sbi, segno, off); - if (err == GC_NEXT) + if (check_valid_map(sbi, segno, off) == 0) continue; if (initial) { @@ -424,7 +416,6 @@ next_step: }; sync_node_pages(sbi, 0, &wbc); } - return GC_DONE; } /* @@ -467,13 +458,13 @@ static int check_dnode(struct f2fs_sb_info *sbi, struct f2fs_summary *sum, node_page = get_node_page(sbi, nid); if (IS_ERR(node_page)) - return GC_NEXT; + return 0; get_node_info(sbi, nid, dni); if (sum->version != dni->version) { f2fs_put_page(node_page, 1); - return GC_NEXT; + return 0; } *nofs = ofs_of_node(node_page); @@ -481,8 +472,8 @@ static int check_dnode(struct f2fs_sb_info *sbi, struct f2fs_summary *sum, f2fs_put_page(node_page, 1); if (source_blkaddr != blkaddr) - return GC_NEXT; - return GC_OK; + return 0; + return 1; } static void move_data_page(struct inode *inode, struct page *page, int gc_type) @@ -523,13 +514,13 @@ out: * If the parent node is not valid or the data block address is different, * the victim data block is ignored. */ -static int gc_data_segment(struct f2fs_sb_info *sbi, struct f2fs_summary *sum, +static void gc_data_segment(struct f2fs_sb_info *sbi, struct f2fs_summary *sum, struct list_head *ilist, unsigned int segno, int gc_type) { struct super_block *sb = sbi->sb; struct f2fs_summary *entry; block_t start_addr; - int err, off; + int off; int phase = 0; start_addr = START_BLOCK(sbi, segno); @@ -543,20 +534,11 @@ next_step: unsigned int ofs_in_node, nofs; block_t start_bidx; - /* - * It makes sure that free segments are able to write - * all the dirty node pages before CP after this CP. - * So let's check the space of dirty node pages. - */ - if (should_do_checkpoint(sbi)) { - mutex_lock(&sbi->cp_mutex); - block_operations(sbi); - err = GC_BLOCKED; - goto stop; - } + /* stop BG_GC if there is not enough free sections. */ + if (gc_type == BG_GC && has_not_enough_free_secs(sbi, 0)) + return; - err = check_valid_map(sbi, segno, off); - if (err == GC_NEXT) + if (check_valid_map(sbi, segno, off) == 0) continue; if (phase == 0) { @@ -565,8 +547,7 @@ next_step: } /* Get an inode by ino with checking validity */ - err = check_dnode(sbi, entry, &dni, start_addr + off, &nofs); - if (err == GC_NEXT) + if (check_dnode(sbi, entry, &dni, start_addr + off, &nofs) == 0) continue; if (phase == 1) { @@ -606,11 +587,9 @@ next_iput: } if (++phase < 4) goto next_step; - err = GC_DONE; -stop: + if (gc_type == FG_GC) f2fs_submit_bio(sbi, DATA, true); - return err; } static int __get_victim(struct f2fs_sb_info *sbi, unsigned int *victim, @@ -624,17 +603,16 @@ static int __get_victim(struct f2fs_sb_info *sbi, unsigned int *victim, return ret; } -static int do_garbage_collect(struct f2fs_sb_info *sbi, unsigned int segno, +static void do_garbage_collect(struct f2fs_sb_info *sbi, unsigned int segno, struct list_head *ilist, int gc_type) { struct page *sum_page; struct f2fs_summary_block *sum; - int ret = GC_DONE; /* read segment summary of victim */ sum_page = get_sum_page(sbi, segno); if (IS_ERR(sum_page)) - return GC_ERROR; + return; /* * CP needs to lock sum_page. In this time, we don't need @@ -646,17 +624,16 @@ static int do_garbage_collect(struct f2fs_sb_info *sbi, unsigned int segno, switch (GET_SUM_TYPE((&sum->footer))) { case SUM_TYPE_NODE: - ret = gc_node_segment(sbi, sum->entries, segno, gc_type); + gc_node_segment(sbi, sum->entries, segno, gc_type); break; case SUM_TYPE_DATA: - ret = gc_data_segment(sbi, sum->entries, ilist, segno, gc_type); + gc_data_segment(sbi, sum->entries, ilist, segno, gc_type); break; } stat_inc_seg_count(sbi, GET_SUM_TYPE((&sum->footer))); stat_inc_call_count(sbi->stat_info); f2fs_put_page(sum_page, 0); - return ret; } int f2fs_gc(struct f2fs_sb_info *sbi) @@ -664,40 +641,38 @@ int f2fs_gc(struct f2fs_sb_info *sbi) struct list_head ilist; unsigned int segno, i; int gc_type = BG_GC; - int gc_status = GC_NONE; + int nfree = 0; + int ret = -1; INIT_LIST_HEAD(&ilist); gc_more: if (!(sbi->sb->s_flags & MS_ACTIVE)) goto stop; - if (gc_type == BG_GC && has_not_enough_free_secs(sbi)) + if (gc_type == BG_GC && has_not_enough_free_secs(sbi, nfree)) gc_type = FG_GC; if (!__get_victim(sbi, &segno, gc_type, NO_CHECK_TYPE)) goto stop; + ret = 0; - for (i = 0; i < sbi->segs_per_sec; i++) { - /* - * do_garbage_collect will give us three gc_status: - * GC_ERROR, GC_DONE, and GC_BLOCKED. - * If GC is finished uncleanly, we have to return - * the victim to dirty segment list. - */ - gc_status = do_garbage_collect(sbi, segno + i, &ilist, gc_type); - if (gc_status != GC_DONE) - break; - } - if (has_not_enough_free_secs(sbi)) { - write_checkpoint(sbi, (gc_status == GC_BLOCKED), false); - if (has_not_enough_free_secs(sbi)) - goto gc_more; - } + for (i = 0; i < sbi->segs_per_sec; i++) + do_garbage_collect(sbi, segno + i, &ilist, gc_type); + + if (gc_type == FG_GC && + get_valid_blocks(sbi, segno, sbi->segs_per_sec) == 0) + nfree++; + + if (has_not_enough_free_secs(sbi, nfree)) + goto gc_more; + + if (gc_type == FG_GC) + write_checkpoint(sbi, false); stop: mutex_unlock(&sbi->gc_mutex); put_gc_inode(&ilist); - return gc_status; + return ret; } void build_gc_manager(struct f2fs_sb_info *sbi) diff --git a/fs/f2fs/gc.h b/fs/f2fs/gc.h index c407a75a7daa..30b2db003acd 100644 --- a/fs/f2fs/gc.h +++ b/fs/f2fs/gc.h @@ -22,15 +22,6 @@ /* Search max. number of dirty segments to select a victim segment */ #define MAX_VICTIM_SEARCH 20 -enum { - GC_NONE = 0, - GC_ERROR, - GC_OK, - GC_NEXT, - GC_BLOCKED, - GC_DONE, -}; - struct f2fs_gc_kthread { struct task_struct *f2fs_gc_task; wait_queue_head_t gc_wait_queue_head; @@ -103,10 +94,3 @@ static inline int is_idle(struct f2fs_sb_info *sbi) struct request_list *rl = &q->root_rl; return !(rl->count[BLK_RW_SYNC]) && !(rl->count[BLK_RW_ASYNC]); } - -static inline bool should_do_checkpoint(struct f2fs_sb_info *sbi) -{ - int node_secs = get_blocktype_secs(sbi, F2FS_DIRTY_NODES); - int dent_secs = get_blocktype_secs(sbi, F2FS_DIRTY_DENTS); - return free_sections(sbi) <= (node_secs + 2 * dent_secs + 2); -} diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c index 33fa6d506d94..43ce16422b75 100644 --- a/fs/f2fs/node.c +++ b/fs/f2fs/node.c @@ -1135,7 +1135,7 @@ static int f2fs_write_node_pages(struct address_space *mapping, /* First check balancing cached NAT entries */ if (try_to_free_nats(sbi, NAT_ENTRY_PER_BLOCK)) { - write_checkpoint(sbi, false, false); + write_checkpoint(sbi, false); return 0; } diff --git a/fs/f2fs/recovery.c b/fs/f2fs/recovery.c index e2a3e1a8eae9..01e1a03b54c8 100644 --- a/fs/f2fs/recovery.c +++ b/fs/f2fs/recovery.c @@ -373,5 +373,5 @@ void recover_fsync_data(struct f2fs_sb_info *sbi) out: destroy_fsync_dnodes(sbi, &inode_list); kmem_cache_destroy(fsync_entry_slab); - write_checkpoint(sbi, false, false); + write_checkpoint(sbi, false); } diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c index 7aa270f3538a..777f17e496e6 100644 --- a/fs/f2fs/segment.c +++ b/fs/f2fs/segment.c @@ -29,7 +29,7 @@ void f2fs_balance_fs(struct f2fs_sb_info *sbi) * We should do GC or end up with checkpoint, if there are so many dirty * dir/node pages without enough free segments. */ - if (has_not_enough_free_secs(sbi)) { + if (has_not_enough_free_secs(sbi, 0)) { mutex_lock(&sbi->gc_mutex); f2fs_gc(sbi); } @@ -308,7 +308,7 @@ static unsigned int check_prefree_segments(struct f2fs_sb_info *sbi, * If there is not enough reserved sections, * we should not reuse prefree segments. */ - if (has_not_enough_free_secs(sbi)) + if (has_not_enough_free_secs(sbi, 0)) return NULL_SEGNO; /* @@ -536,6 +536,23 @@ static void change_curseg(struct f2fs_sb_info *sbi, int type, bool reuse) } } +static int get_ssr_segment(struct f2fs_sb_info *sbi, int type) +{ + struct curseg_info *curseg = CURSEG_I(sbi, type); + const struct victim_selection *v_ops = DIRTY_I(sbi)->v_ops; + + if (IS_NODESEG(type) || !has_not_enough_free_secs(sbi, 0)) + return v_ops->get_victim(sbi, + &(curseg)->next_segno, BG_GC, type, SSR); + + /* For data segments, let's do SSR more intensively */ + for (; type >= CURSEG_HOT_DATA; type--) + if (v_ops->get_victim(sbi, &(curseg)->next_segno, + BG_GC, type, SSR)) + return 1; + return 0; +} + /* * flush out current segment and replace it with new segment * This function should be returned with success, otherwise BUG diff --git a/fs/f2fs/segment.h b/fs/f2fs/segment.h index 458bf5c726f7..552dadbb2327 100644 --- a/fs/f2fs/segment.h +++ b/fs/f2fs/segment.h @@ -450,21 +450,15 @@ static inline bool need_SSR(struct f2fs_sb_info *sbi) return (free_sections(sbi) < overprovision_sections(sbi)); } -static inline int get_ssr_segment(struct f2fs_sb_info *sbi, int type) -{ - struct curseg_info *curseg = CURSEG_I(sbi, type); - return DIRTY_I(sbi)->v_ops->get_victim(sbi, - &(curseg)->next_segno, BG_GC, type, SSR); -} - -static inline bool has_not_enough_free_secs(struct f2fs_sb_info *sbi) +static inline bool has_not_enough_free_secs(struct f2fs_sb_info *sbi, int freed) { int node_secs = get_blocktype_secs(sbi, F2FS_DIRTY_NODES); int dent_secs = get_blocktype_secs(sbi, F2FS_DIRTY_DENTS); + if (sbi->por_doing) return false; - return (free_sections(sbi) <= (node_secs + 2 * dent_secs + + return ((free_sections(sbi) + freed) <= (node_secs + 2 * dent_secs + reserved_sections(sbi))); } diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c index ddb665f54d17..8c117649a035 100644 --- a/fs/f2fs/super.c +++ b/fs/f2fs/super.c @@ -112,7 +112,7 @@ static void f2fs_put_super(struct super_block *sb) f2fs_destroy_stats(sbi); stop_gc_thread(sbi); - write_checkpoint(sbi, false, true); + write_checkpoint(sbi, true); iput(sbi->node_inode); iput(sbi->meta_inode); @@ -136,7 +136,7 @@ int f2fs_sync_fs(struct super_block *sb, int sync) return 0; if (sync) - write_checkpoint(sbi, false, false); + write_checkpoint(sbi, false); else f2fs_balance_fs(sbi); 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