f2fs: split journal cache from curseg cache
PATCH 2/7 f2fs: split journal cache from curseg cache
In curseg cache, f2fs cached two different parts:
- datas of current summay block
- journal info consist of sparse nat/sit entries
And we use the same curseg_mutex lock to protect these two caches.
With this approach, on the one hand, it may cause higher lock contention when accessing/updating one of two parts of cache since we use the same lock curseg_mutex to avoid contention. On the other hand, for now, journal info was cached in current summary block after ->mount or last checkpoint, so these junk journals could be writebacked into most summary blocks, it wastes remained space of summary block.
So, in order to fix above issues, we split curseg cache into two parts:
a) journal cache, protected by r/w semaphore journal_rwsem
b) current summary block, protected by mutex lock curseg_mutex
Signed-off-by Chao Yu <[email protected]>
--- fs/f2fs/checkpoint.c | 2 +- fs/f2fs/node.c | 26 ++++++++-------- fs/f2fs/segment.c | 85 +++++++++++++++++++++++++++++++++++++--------------- fs/f2fs/segment.h | 2 ++ 4 files changed, 77 insertions(+), 38 deletions(-)
fs/f2fs/checkpoint.c +1 -1
@@ -1051,7 +1051,7 @@ static int do_checkpoint(struct f2fs_sb_info *sbi, struct cp_control *cpc)if (sb->s_bdev->bd_part) kbytes_written +=BD_PART_WRITTEN (sbi); - seg_i->sum_blk->journal.info.kbytes_written =cpu_to_le64 (kbytes_written); + seg_i->journal->info.kbytes_written =cpu_to_le64 (kbytes_written);if (__remain_node_summaries (cpc->reason)) {write_node_summaries (sbi, start_blk);
fs/f2fs/node.c +13 -13
@@ -354,7 +354,7 @@ void get_node_info(struct f2fs_sb_info *sbi, nid_t nid, struct node_info *ni) {struct f2fs_nm_info *nm_i =NM_I (sbi);struct curseg_info *curseg =CURSEG_I (sbi,CURSEG_HOT_DATA ); -struct f2fs_journal *journal = &curseg->sum_blk->journal; +struct f2fs_journal *journal = curseg->journal;nid_t start_nid =START_NID (nid);struct f2fs_nat_block *nat_blk;struct page *page =NULL ;
@@ -381,13 +381,13 @@ void get_node_info(struct f2fs_sb_info *sbi, nid_t nid, struct node_info *ni)down_write (&nm_i->nat_tree_lock);/* Check current segment summary */ -mutex_lock (&curseg->curseg_mutex); +down_read (&curseg->journal_rwsem); i =lookup_journal_in_cursum (journal,NAT_JOURNAL , nid,0 );if (i >=0 ) { ne =nat_in_journal (journal, i);node_info_from_raw_nat (ni, &ne); } -mutex_unlock (&curseg->curseg_mutex); +up_read (&curseg->journal_rwsem);if (i >=0 ) goto cache;
@@ -1613,7 +1613,7 @@ static void build_free_nids(struct f2fs_sb_info *sbi) {struct f2fs_nm_info *nm_i =NM_I (sbi);struct curseg_info *curseg =CURSEG_I (sbi,CURSEG_HOT_DATA ); -struct f2fs_journal *journal = &curseg->sum_blk->journal; +struct f2fs_journal *journal = curseg->journal;int i =0 ;nid_t nid = nm_i->next_scan_nid;
@@ -1645,7 +1645,7 @@ static void build_free_nids(struct f2fs_sb_info *sbi) nm_i->next_scan_nid = nid;/* find free nids from current sum_pages */ -mutex_lock (&curseg->curseg_mutex); +down_read (&curseg->journal_rwsem);for (i =0 ; i <nats_in_cursum (journal); i++) {block_t addr;
@@ -1656,7 +1656,7 @@ static void build_free_nids(struct f2fs_sb_info *sbi)else remove_free_nid (nm_i, nid); } -mutex_unlock (&curseg->curseg_mutex); +up_read (&curseg->journal_rwsem);up_read (&nm_i->nat_tree_lock); ra_meta_pages(sbi, NAT_BLOCK_OFFSET(nm_i->next_scan_nid),
@@ -1920,10 +1920,10 @@ static void remove_nats_in_journal(struct f2fs_sb_info *sbi) {struct f2fs_nm_info *nm_i =NM_I (sbi);struct curseg_info *curseg =CURSEG_I (sbi,CURSEG_HOT_DATA ); -struct f2fs_journal *journal = &curseg->sum_blk->journal; +struct f2fs_journal *journal = curseg->journal;int i; -mutex_lock (&curseg->curseg_mutex); +down_write (&curseg->journal_rwsem);for (i =0 ; i <nats_in_cursum (journal); i++) {struct nat_entry *ne;struct f2fs_nat_entry raw_ne;
@@ -1939,7 +1939,7 @@ static void remove_nats_in_journal(struct f2fs_sb_info *sbi)__set_nat_cache_dirty (nm_i, ne); }update_nats_in_cursum (journal, -i); -mutex_unlock (&curseg->curseg_mutex); +up_write (&curseg->journal_rwsem); } static void __adjust_nat_entry_set(struct nat_entry_set *nes,
@@ -1964,7 +1964,7 @@ static void __flush_nat_entry_set(struct f2fs_sb_info *sbi, struct nat_entry_set *set) {struct curseg_info *curseg =CURSEG_I (sbi,CURSEG_HOT_DATA ); -struct f2fs_journal *journal = &curseg->sum_blk->journal; +struct f2fs_journal *journal = curseg->journal;nid_t start_nid = set->set *NAT_ENTRY_PER_BLOCK ;bool to_journal = true;struct f2fs_nat_block *nat_blk;
@@ -1980,7 +1980,7 @@ static void __flush_nat_entry_set(struct f2fs_sb_info *sbi, to_journal = false;if (to_journal) { -mutex_lock (&curseg->curseg_mutex); +down_write (&curseg->journal_rwsem); }else { page =get_next_nat_page (sbi, start_nid); nat_blk =page_address (page);
@@ -2013,7 +2013,7 @@ static void __flush_nat_entry_set(struct f2fs_sb_info *sbi, }if (to_journal) -mutex_unlock (&curseg->curseg_mutex); +up_write (&curseg->journal_rwsem);else f2fs_put_page (page,1 );
@@ -2030,7 +2030,7 @@ void flush_nat_entries(struct f2fs_sb_info *sbi) {struct f2fs_nm_info *nm_i =NM_I (sbi);struct curseg_info *curseg =CURSEG_I (sbi,CURSEG_HOT_DATA ); -struct f2fs_journal *journal = &curseg->sum_blk->journal; +struct f2fs_journal *journal = curseg->journal;struct nat_entry_set *setvec[SETVEC_SIZE ];struct nat_entry_set *set, *tmp;unsigned int found;
fs/f2fs/segment.c +61 -24
197 lines not on this page · raw message
fs/f2fs/segment.h +2 -0
@@ -258,6 +258,8 @@ struct victim_selection {struct curseg_info {struct mutex curseg_mutex;/* lock for consistency */ struct f2fs_summary_block *sum_blk;/* cached summary block */ +struct rw_semaphore journal_rwsem;/* protect journal area */ +struct f2fs_journal *journal;/* cached journal info */ unsigned char alloc_type;/* current allocation type */ unsigned int segno;/* current segment number */ unsigned short next_blkoff;/* next block offset to write */
Signature · 1 line
2.7.0.2.g1b0b6dd