f2fs: do retry operations with cond_resched

This patch revists retrial paths in f2fs.
The basic idea is to use cond_resched instead of retrying from the very early
stage.

Suggested-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

4 files changed, 20 insertions, 38 deletions

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index c87314099d26..c787fe302918 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -1021,6 +1021,13 @@ retry:
         return entry;
 }
 
+static inline void f2fs_radix_tree_insert(struct radix_tree_root *root,
+                                unsigned long index, void *item)
+{
+        while (radix_tree_insert(root, index, item))
+                cond_resched();
+}
+
 #define RAW_IS_INODE(p) ((p)->footer.nid == (p)->footer.ino)
 
 static inline bool IS_INODE(struct page *page)
diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
index 2c58c587a3c6..eec0933a4819 100644
--- a/fs/f2fs/gc.c
+++ b/fs/f2fs/gc.c
@@ -356,12 +356,11 @@ static void add_gc_inode(struct gc_inode_list *gc_list, struct inode *inode)
                 iput(inode);
                 return;
         }
-retry:
         new_ie = f2fs_kmem_cache_alloc(winode_slab, GFP_NOFS);
         new_ie->inode = inode;
-
+retry:
         if (radix_tree_insert(&gc_list->iroot, inode->i_ino, new_ie)) {
-                kmem_cache_free(winode_slab, new_ie);
+                cond_resched();
                 goto retry;
         }
         list_add_tail(&new_ie->list, &gc_list->ilist);
diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
index 8de4f555d530..f83326ca32ef 100644
--- a/fs/f2fs/node.c
+++ b/fs/f2fs/node.c
@@ -147,7 +147,7 @@ static void __set_nat_cache_dirty(struct f2fs_nm_info *nm_i,
 
         if (get_nat_flag(ne, IS_DIRTY))
                 return;
-retry:
+
         head = radix_tree_lookup(&nm_i->nat_set_root, set);
         if (!head) {
                 head = f2fs_kmem_cache_alloc(nat_entry_set_slab, GFP_ATOMIC);
@@ -156,11 +156,7 @@ retry:
                 INIT_LIST_HEAD(&head->set_list);
                 head->set = set;
                 head->entry_cnt = 0;
-
-                if (radix_tree_insert(&nm_i->nat_set_root, set, head)) {
-                        kmem_cache_free(nat_entry_set_slab, head);
-                        goto retry;
-                }
+                f2fs_radix_tree_insert(&nm_i->nat_set_root, set, head);
         }
         list_move_tail(&ne->list, &head->entry_list);
         nm_i->dirty_nat_cnt++;
@@ -238,13 +234,8 @@ static struct nat_entry *grab_nat_entry(struct f2fs_nm_info *nm_i, nid_t nid)
 {
         struct nat_entry *new;
 
-        new = kmem_cache_alloc(nat_entry_slab, GFP_ATOMIC);
-        if (!new)
-                return NULL;
-        if (radix_tree_insert(&nm_i->nat_root, nid, new)) {
-                kmem_cache_free(nat_entry_slab, new);
-                return NULL;
-        }
+        new = f2fs_kmem_cache_alloc(nat_entry_slab, GFP_ATOMIC);
+        f2fs_radix_tree_insert(&nm_i->nat_root, nid, new);
         memset(new, 0, sizeof(struct nat_entry));
         nat_set_nid(new, nid);
         nat_reset_flag(new);
@@ -257,15 +248,11 @@ static void cache_nat_entry(struct f2fs_nm_info *nm_i, nid_t nid,
                                                 struct f2fs_nat_entry *ne)
 {
         struct nat_entry *e;
-retry:
+
         down_write(&nm_i->nat_tree_lock);
         e = __lookup_nat_cache(nm_i, nid);
         if (!e) {
                 e = grab_nat_entry(nm_i, nid);
-                if (!e) {
-                        up_write(&nm_i->nat_tree_lock);
-                        goto retry;
-                }
                 node_info_from_raw_nat(&e->ni, ne);
         }
         up_write(&nm_i->nat_tree_lock);
@@ -276,15 +263,11 @@ static void set_node_addr(struct f2fs_sb_info *sbi, struct node_info *ni,
 {
         struct f2fs_nm_info *nm_i = NM_I(sbi);
         struct nat_entry *e;
-retry:
+
         down_write(&nm_i->nat_tree_lock);
         e = __lookup_nat_cache(nm_i, ni->nid);
         if (!e) {
                 e = grab_nat_entry(nm_i, ni->nid);
-                if (!e) {
-                        up_write(&nm_i->nat_tree_lock);
-                        goto retry;
-                }
                 e->ni = *ni;
                 f2fs_bug_on(sbi, ni->blk_addr == NEW_ADDR);
         } else if (new_blkaddr == NEW_ADDR) {
@@ -1833,19 +1816,13 @@ static void remove_nats_in_journal(struct f2fs_sb_info *sbi)
                 nid_t nid = le32_to_cpu(nid_in_journal(sum, i));
 
                 raw_ne = nat_in_journal(sum, i);
-retry:
+
                 down_write(&nm_i->nat_tree_lock);
                 ne = __lookup_nat_cache(nm_i, nid);
-                if (ne)
-                        goto found;
-
-                ne = grab_nat_entry(nm_i, nid);
                 if (!ne) {
-                        up_write(&nm_i->nat_tree_lock);
-                        goto retry;
+                        ne = grab_nat_entry(nm_i, nid);
+                        node_info_from_raw_nat(&ne->ni, &raw_ne);
                 }
-                node_info_from_raw_nat(&ne->ni, &raw_ne);
-found:
                 __set_nat_cache_dirty(nm_i, ne);
                 up_write(&nm_i->nat_tree_lock);
         }
diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
index 9a33e34d26ce..c79d67e5045f 100644
--- a/fs/f2fs/segment.c
+++ b/fs/f2fs/segment.c
@@ -179,13 +179,13 @@ void register_inmem_page(struct inode *inode, struct page *page)
         struct f2fs_inode_info *fi = F2FS_I(inode);
         struct inmem_pages *new;
         int err;
-retry:
+
         new = f2fs_kmem_cache_alloc(inmem_entry_slab, GFP_NOFS);
 
         /* add atomic page indices to the list */
         new->page = page;
         INIT_LIST_HEAD(&new->list);
-
+retry:
         /* increase reference count with clean state */
         mutex_lock(&fi->inmem_lock);
         err = radix_tree_insert(&fi->inmem_root, page->index, new);
@@ -195,7 +195,6 @@ retry:
                 return;
         } else if (err) {
                 mutex_unlock(&fi->inmem_lock);
-                kmem_cache_free(inmem_entry_slab, new);
                 goto retry;
         }
         get_page(page);