f2fs: adjust free mem size to flush dentry blocks

If so many dirty dentry blocks are cached, not reached to the flush condition,
we should fall into livelock in balance_dirty_pages.
So, let's consider the mem size for the condition.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>

4 files changed, 32 insertions, 21 deletions

diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index b5cd6d1c9320..6b89b2517edf 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -863,7 +863,8 @@ static int f2fs_write_data_pages(struct address_space *mapping,
                 return 0;
 
         if (S_ISDIR(inode->i_mode) && wbc->sync_mode == WB_SYNC_NONE &&
-                        get_dirty_dents(inode) < nr_pages_to_skip(sbi, DATA))
+                        get_dirty_dents(inode) < nr_pages_to_skip(sbi, DATA) &&
+                        available_free_memory(sbi, DIRTY_DENTS))
                 goto skip_write;
 
         diff = nr_pages_to_write(sbi, DATA, wbc);
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 556d06b67e6a..97da71d96ce3 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -1143,6 +1143,7 @@ f2fs_hash_t f2fs_dentry_hash(const char *, size_t);
 struct dnode_of_data;
 struct node_info;
 
+bool available_free_memory(struct f2fs_sb_info *, int);
 int is_checkpointed_node(struct f2fs_sb_info *, nid_t);
 bool fsync_mark_done(struct f2fs_sb_info *, nid_t);
 void get_node_info(struct f2fs_sb_info *, nid_t, struct node_info *);
diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
index 64755f49d6e7..2803ef6cf533 100644
--- a/fs/f2fs/node.c
+++ b/fs/f2fs/node.c
@@ -26,20 +26,26 @@
 static struct kmem_cache *nat_entry_slab;
 static struct kmem_cache *free_nid_slab;
 
-static inline bool available_free_memory(struct f2fs_nm_info *nm_i, int type)
+bool available_free_memory(struct f2fs_sb_info *sbi, int type)
 {
+        struct f2fs_nm_info *nm_i = NM_I(sbi);
         struct sysinfo val;
         unsigned long mem_size = 0;
+        bool res = false;
 
         si_meminfo(&val);
-        if (type == FREE_NIDS)
-                mem_size = nm_i->fcnt * sizeof(struct free_nid);
-        else if (type == NAT_ENTRIES)
-                mem_size += nm_i->nat_cnt * sizeof(struct nat_entry);
-        mem_size >>= 12;
-
-        /* give 50:50 memory for free nids and nat caches respectively */
-        return (mem_size < ((val.totalram * nm_i->ram_thresh) >> 11));
+        /* give 25%, 25%, 50% memory for each components respectively */
+        if (type == FREE_NIDS) {
+                mem_size = (nm_i->fcnt * sizeof(struct free_nid)) >> 12;
+                res = mem_size < ((val.totalram * nm_i->ram_thresh / 100) >> 2);
+        } else if (type == NAT_ENTRIES) {
+                mem_size = (nm_i->nat_cnt * sizeof(struct nat_entry)) >> 12;
+                res = mem_size < ((val.totalram * nm_i->ram_thresh / 100) >> 2);
+        } else if (type == DIRTY_DENTS) {
+                mem_size = get_pages(sbi, F2FS_DIRTY_DENTS);
+                res = mem_size < ((val.totalram * nm_i->ram_thresh / 100) >> 1);
+        }
+        return res;
 }
 
 static void clear_node_page_dirty(struct page *page)
@@ -241,7 +247,7 @@ int try_to_free_nats(struct f2fs_sb_info *sbi, int nr_shrink)
 {
         struct f2fs_nm_info *nm_i = NM_I(sbi);
 
-        if (available_free_memory(nm_i, NAT_ENTRIES))
+        if (available_free_memory(sbi, NAT_ENTRIES))
                 return 0;
 
         write_lock(&nm_i->nat_tree_lock);
@@ -1310,13 +1316,14 @@ static void __del_from_free_nid_list(struct f2fs_nm_info *nm_i,
         radix_tree_delete(&nm_i->free_nid_root, i->nid);
 }
 
-static int add_free_nid(struct f2fs_nm_info *nm_i, nid_t nid, bool build)
+static int add_free_nid(struct f2fs_sb_info *sbi, nid_t nid, bool build)
 {
+        struct f2fs_nm_info *nm_i = NM_I(sbi);
         struct free_nid *i;
         struct nat_entry *ne;
         bool allocated = false;
 
-        if (!available_free_memory(nm_i, FREE_NIDS))
+        if (!available_free_memory(sbi, FREE_NIDS))
                 return -1;
 
         /* 0 nid should not be used */
@@ -1369,9 +1376,10 @@ static void remove_free_nid(struct f2fs_nm_info *nm_i, nid_t nid)
                 kmem_cache_free(free_nid_slab, i);
 }
 
-static void scan_nat_page(struct f2fs_nm_info *nm_i,
+static void scan_nat_page(struct f2fs_sb_info *sbi,
                         struct page *nat_page, nid_t start_nid)
 {
+        struct f2fs_nm_info *nm_i = NM_I(sbi);
         struct f2fs_nat_block *nat_blk = page_address(nat_page);
         block_t blk_addr;
         int i;
@@ -1386,7 +1394,7 @@ static void scan_nat_page(struct f2fs_nm_info *nm_i,
                 blk_addr = le32_to_cpu(nat_blk->entries[i].block_addr);
                 f2fs_bug_on(blk_addr == NEW_ADDR);
                 if (blk_addr == NULL_ADDR) {
-                        if (add_free_nid(nm_i, start_nid, true) < 0)
+                        if (add_free_nid(sbi, start_nid, true) < 0)
                                 break;
                 }
         }
@@ -1410,7 +1418,7 @@ static void build_free_nids(struct f2fs_sb_info *sbi)
         while (1) {
                 struct page *page = get_current_nat_page(sbi, nid);
 
-                scan_nat_page(nm_i, page, nid);
+                scan_nat_page(sbi, page, nid);
                 f2fs_put_page(page, 1);
 
                 nid += (NAT_ENTRY_PER_BLOCK - (nid % NAT_ENTRY_PER_BLOCK));
@@ -1430,7 +1438,7 @@ static void build_free_nids(struct f2fs_sb_info *sbi)
                 block_t addr = le32_to_cpu(nat_in_journal(sum, i).block_addr);
                 nid = le32_to_cpu(nid_in_journal(sum, i));
                 if (addr == NULL_ADDR)
-                        add_free_nid(nm_i, nid, true);
+                        add_free_nid(sbi, nid, true);
                 else
                         remove_free_nid(nm_i, nid);
         }
@@ -1507,7 +1515,7 @@ void alloc_nid_failed(struct f2fs_sb_info *sbi, nid_t nid)
         spin_lock(&nm_i->free_nid_list_lock);
         i = __lookup_free_nid_list(nm_i, nid);
         f2fs_bug_on(!i || i->state != NID_ALLOC);
-        if (!available_free_memory(nm_i, FREE_NIDS)) {
+        if (!available_free_memory(sbi, FREE_NIDS)) {
                 __del_from_free_nid_list(nm_i, i);
                 need_free = true;
         } else {
@@ -1835,7 +1843,7 @@ flush_now:
                 }
 
                 if (nat_get_blkaddr(ne) == NULL_ADDR &&
-                                add_free_nid(NM_I(sbi), nid, false) <= 0) {
+                                add_free_nid(sbi, nid, false) <= 0) {
                         write_lock(&nm_i->nat_tree_lock);
                         __del_from_nat_cache(nm_i, ne);
                         write_unlock(&nm_i->nat_tree_lock);
diff --git a/fs/f2fs/node.h b/fs/f2fs/node.h
index 41bb65b1c97d..a076c88bdca5 100644
--- a/fs/f2fs/node.h
+++ b/fs/f2fs/node.h
@@ -83,9 +83,10 @@ static inline void raw_nat_from_node_info(struct f2fs_nat_entry *raw_ne,
         raw_ne->version = ni->version;
 }
 
-enum nid_type {
+enum mem_type {
         FREE_NIDS,      /* indicates the free nid list */
-        NAT_ENTRIES     /* indicates the cached nat entry */
+        NAT_ENTRIES,    /* indicates the cached nat entry */
+        DIRTY_DENTS     /* indicates dirty dentry pages */
 };
 
 /*