f2fs: control not to exceed # of cached nat entries
This is to avoid cache entry management overhead including radix tree.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
diff --git a/fs/f2fs/node.h b/fs/f2fs/node.h
index 2c2a797..673ce92 100644
--- a/fs/f2fs/node.h
+++ b/fs/f2fs/node.h
@@ -27,6 +27,8 @@
/* control dirty nats ratio threshold (default: 10% over max nid count) */
#define DEF_DIRTY_NAT_RATIO_THRESHOLD 10
+/* control total # of nats */
+#define DEF_NAT_CACHE_THRESHOLD 100000
/* vector size for gang look-up from nat cache that consists of radix tree */
#define NATVEC_SIZE 64
@@ -126,6 +128,11 @@
NM_I(sbi)->dirty_nats_ratio / 100;
}
+static inline bool excess_cached_nats(struct f2fs_sb_info *sbi)
+{
+ return NM_I(sbi)->nat_cnt >= DEF_NAT_CACHE_THRESHOLD;
+}
+
enum mem_type {
FREE_NIDS, /* indicates the free nid list */
NAT_ENTRIES, /* indicates the cached nat entry */