f2fs: speed up gc_urgent mode with SSR

This patch activates SSR in gc_urgent mode.

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

fs/f2fs/f2fs.h

@@ -2511,6 +2511,7 @@ void destroy_node_manager_caches(void);
 /*
  * segment.c
  */
+bool need_SSR(struct f2fs_sb_info *sbi);
 void register_inmem_page(struct inode *inode, struct page *page);
 void drop_inmem_pages(struct inode *inode);
 void drop_inmem_page(struct inode *inode, struct page *page);

fs/f2fs/segment.c

@@ -169,6 +169,21 @@ static unsigned long __find_rev_next_zero_bit(const unsigned long *addr,
 	return result - size + __reverse_ffz(tmp);
 }
 
+bool need_SSR(struct f2fs_sb_info *sbi)
+{
+	int node_secs = get_blocktype_secs(sbi, F2FS_DIRTY_NODES);
+	int dent_secs = get_blocktype_secs(sbi, F2FS_DIRTY_DENTS);
+	int imeta_secs = get_blocktype_secs(sbi, F2FS_DIRTY_IMETA);
+
+	if (test_opt(sbi, LFS))
+		return false;
+	if (sbi->gc_thread && sbi->gc_thread->gc_urgent)
+		return true;
+
+	return free_sections(sbi) <= (node_secs + 2 * dent_secs + imeta_secs +
+						2 * reserved_sections(sbi));
+}
+
 void register_inmem_page(struct inode *inode, struct page *page)
 {
 	struct f2fs_inode_info *fi = F2FS_I(inode);

fs/f2fs/segment.h

@@ -497,19 +497,6 @@ static inline int reserved_sections(struct f2fs_sb_info *sbi)
 	return GET_SEC_FROM_SEG(sbi, (unsigned int)reserved_segments(sbi));
 }
 
-static inline bool need_SSR(struct f2fs_sb_info *sbi)
-{
-	int node_secs = get_blocktype_secs(sbi, F2FS_DIRTY_NODES);
-	int dent_secs = get_blocktype_secs(sbi, F2FS_DIRTY_DENTS);
-	int imeta_secs = get_blocktype_secs(sbi, F2FS_DIRTY_IMETA);
-
-	if (test_opt(sbi, LFS))
-		return false;
-
-	return free_sections(sbi) <= (node_secs + 2 * dent_secs + imeta_secs +
-						2 * reserved_sections(sbi));
-}
-
 static inline bool has_not_enough_free_secs(struct f2fs_sb_info *sbi,
 					int freed, int needed)
 {