f2fs: don't interrupt free nids building during nid allocation

Let build_free_nids support sync/async methods, in allocation flow of nids,
we use synchronuous method, so that we can avoid looping in alloc_nid when
free memory is low; in unblock_operations and f2fs_balance_fs_bg we use
asynchronuous method in where low memory condition can interrupt us.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c
index 7db2aa2280ad8428c4f311c5a7177070002baf54..654f5d7f92889a71633ea0caeca6dbf399a7b21c 100644 (file)
--- a/fs/f2fs/checkpoint.c
+++ b/fs/f2fs/checkpoint.c
@@ -987,7 +987,7 @@ static void unblock_operations(struct f2fs_sb_info *sbi)
 {
        up_write(&sbi->node_write);
 
-       build_free_nids(sbi);
+       build_free_nids(sbi, false);
        f2fs_unlock_all(sbi);
 }
 

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 86b543c3defb71702923a036768f66f460236d07..692f08a53a3b764dac46543f74a6045d6cfd5dfe 100644 (file)
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -2040,7 +2040,7 @@ void move_node_page(struct page *, int);
 int fsync_node_pages(struct f2fs_sb_info *, struct inode *,
                        struct writeback_control *, bool);
 int sync_node_pages(struct f2fs_sb_info *, struct writeback_control *);
-void build_free_nids(struct f2fs_sb_info *);
+void build_free_nids(struct f2fs_sb_info *, bool);
 bool alloc_nid(struct f2fs_sb_info *, nid_t *);
 void alloc_nid_done(struct f2fs_sb_info *, nid_t);
 void alloc_nid_failed(struct f2fs_sb_info *, nid_t);

diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
index f21e5bba9483a6e7da20dd4ff580e1818c6439bf..b6894ef3d907770b0273a55eb7b115caeb370fd9 100644 (file)
--- a/fs/f2fs/node.c
+++ b/fs/f2fs/node.c
@@ -1733,9 +1733,6 @@ static int add_free_nid(struct f2fs_sb_info *sbi, nid_t nid, bool build)
        struct nat_entry *ne;
        int err;
 
-       if (!available_free_memory(sbi, FREE_NIDS))
-               return -1;
-
        /* 0 nid should not be used */
        if (unlikely(nid == 0))
                return 0;
@@ -1803,14 +1800,12 @@ static void scan_nat_page(struct f2fs_sb_info *sbi,
 
                blk_addr = le32_to_cpu(nat_blk->entries[i].block_addr);
                f2fs_bug_on(sbi, blk_addr == NEW_ADDR);
-               if (blk_addr == NULL_ADDR) {
-                       if (add_free_nid(sbi, start_nid, true) < 0)
-                               break;
-               }
+               if (blk_addr == NULL_ADDR)
+                       add_free_nid(sbi, start_nid, true);
        }
 }
 
-void __build_free_nids(struct f2fs_sb_info *sbi)
+void __build_free_nids(struct f2fs_sb_info *sbi, bool sync)
 {
        struct f2fs_nm_info *nm_i = NM_I(sbi);
        struct curseg_info *curseg = CURSEG_I(sbi, CURSEG_HOT_DATA);
@@ -1822,6 +1817,9 @@ void __build_free_nids(struct f2fs_sb_info *sbi)
        if (nm_i->nid_cnt[FREE_NID_LIST] >= NAT_ENTRY_PER_BLOCK)
                return;
 
+       if (!sync && !available_free_memory(sbi, FREE_NIDS))
+               return;
+
        /* readahead nat pages to be scanned */
        ra_meta_pages(sbi, NAT_BLOCK_OFFSET(nid), FREE_NID_PAGES,
                                                        META_NAT, true);
@@ -1864,10 +1862,10 @@ void __build_free_nids(struct f2fs_sb_info *sbi)
                                        nm_i->ra_nid_pages, META_NAT, false);
 }
 
-void build_free_nids(struct f2fs_sb_info *sbi)
+void build_free_nids(struct f2fs_sb_info *sbi, bool sync)
 {
        mutex_lock(&NM_I(sbi)->build_lock);
-       __build_free_nids(sbi);
+       __build_free_nids(sbi, sync);
        mutex_unlock(&NM_I(sbi)->build_lock);
 }
 
@@ -1906,7 +1904,7 @@ retry:
        spin_unlock(&nm_i->nid_list_lock);
 
        /* Let's scan nat pages and its caches to get free nids */
-       build_free_nids(sbi);
+       build_free_nids(sbi, true);
        goto retry;
 }
 
@@ -2343,7 +2341,7 @@ int build_node_manager(struct f2fs_sb_info *sbi)
        if (err)
                return err;
 
-       build_free_nids(sbi);
+       build_free_nids(sbi, true);
        return 0;
 }
 

diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
index 5e1b4a9e2cd2de953b1377daa5c224dfe5e8e897..de597ccdd107fe62b0d815b60e4a7b0191533d91 100644 (file)
--- a/fs/f2fs/segment.c
+++ b/fs/f2fs/segment.c
@@ -382,7 +382,7 @@ void f2fs_balance_fs_bg(struct f2fs_sb_info *sbi)
        if (!available_free_memory(sbi, FREE_NIDS))
                try_to_free_nids(sbi, MAX_FREE_NIDS);
        else
-               build_free_nids(sbi);
+               build_free_nids(sbi, false);
 
        /* checkpoint is the only way to shrink partial cached entries */
        if (!available_free_memory(sbi, NAT_ENTRIES) ||