f2fs: refactor flush_nat_entries to remove costly reorganizing ops
Previously, f2fs tries to reorganize the dirty nat entries into multiple sets
according to its nid ranges. This can improve the flushing nat pages, however,
if there are a lot of cached nat entries, it becomes a bottleneck.
This patch introduces a new set management flow by removing dirty nat list and
adding a series of set operations when the nat entry becomes dirty.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 7b1e1d2..94cfdc4 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -164,6 +164,9 @@
#define sit_in_journal(sum, i) (sum->sit_j.entries[i].se)
#define segno_in_journal(sum, i) (sum->sit_j.entries[i].segno)
+#define MAX_NAT_JENTRIES(sum) (NAT_JOURNAL_ENTRIES - nats_in_cursum(sum))
+#define MAX_SIT_JENTRIES(sum) (SIT_JOURNAL_ENTRIES - sits_in_cursum(sum))
+
static inline int update_nats_in_cursum(struct f2fs_summary_block *rs, int i)
{
int before = nats_in_cursum(rs);
@@ -182,9 +185,8 @@
int type)
{
if (type == NAT_JOURNAL)
- return nats_in_cursum(sum) + size <= NAT_JOURNAL_ENTRIES;
-
- return sits_in_cursum(sum) + size <= SIT_JOURNAL_ENTRIES;
+ return size <= MAX_NAT_JENTRIES(sum);
+ return size <= MAX_SIT_JENTRIES(sum);
}
/*
@@ -292,11 +294,10 @@
/* NAT cache management */
struct radix_tree_root nat_root;/* root of the nat entry cache */
+ struct radix_tree_root nat_set_root;/* root of the nat set cache */
rwlock_t nat_tree_lock; /* protect nat_tree_lock */
- unsigned int nat_cnt; /* the # of cached nat entries */
struct list_head nat_entries; /* cached nat entry list (clean) */
- struct list_head dirty_nat_entries; /* cached nat entry list (dirty) */
- struct list_head nat_entry_set; /* nat entry set list */
+ unsigned int nat_cnt; /* the # of cached nat entries */
unsigned int dirty_nat_cnt; /* total num of nat entries in set */
/* free node ids management */