f2fs: use atomic64_t for extent cache hit stat

Our hit stat of extent cache will increase all the time until remount,
and we use atomic_t type for the stat variable, so it may easily incur
overflow when we query extent cache frequently in a long time running
fs.

So to avoid that, this patch uses atomic64_t for hit stat variables.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
diff --git a/fs/f2fs/debug.c b/fs/f2fs/debug.c
index 615a307..478e5d5 100644
--- a/fs/f2fs/debug.c
+++ b/fs/f2fs/debug.c
@@ -33,11 +33,11 @@
 	int i;
 
 	/* validation check of the segment numbers */
-	si->hit_largest = atomic_read(&sbi->read_hit_largest);
-	si->hit_cached = atomic_read(&sbi->read_hit_cached);
-	si->hit_rbtree = atomic_read(&sbi->read_hit_rbtree);
+	si->hit_largest = atomic64_read(&sbi->read_hit_largest);
+	si->hit_cached = atomic64_read(&sbi->read_hit_cached);
+	si->hit_rbtree = atomic64_read(&sbi->read_hit_rbtree);
 	si->hit_total = si->hit_largest + si->hit_cached + si->hit_rbtree;
-	si->total_ext = atomic_read(&sbi->total_hit_ext);
+	si->total_ext = atomic64_read(&sbi->total_hit_ext);
 	si->ext_tree = sbi->total_ext_tree;
 	si->ext_node = atomic_read(&sbi->total_ext_node);
 	si->ndirty_node = get_pages(sbi, F2FS_DIRTY_NODES);
@@ -283,12 +283,12 @@
 		seq_printf(s, "  - node blocks : %d (%d)\n", si->node_blks,
 				si->bg_node_blks);
 		seq_puts(s, "\nExtent Cache:\n");
-		seq_printf(s, "  - Hit Count: L1-1:%d L1-2:%d L2:%d\n",
+		seq_printf(s, "  - Hit Count: L1-1:%llu L1-2:%llu L2:%llu\n",
 				si->hit_largest, si->hit_cached,
 				si->hit_rbtree);
-		seq_printf(s, "  - Hit Ratio: %d%% (%d / %d)\n",
+		seq_printf(s, "  - Hit Ratio: %llu%% (%llu / %llu)\n",
 				!si->total_ext ? 0 :
-				(si->hit_total * 100) / si->total_ext,
+				div64_u64(si->hit_total * 100, si->total_ext),
 				si->hit_total, si->total_ext);
 		seq_printf(s, "  - Inner Struct Count: tree: %d, node: %d\n",
 				si->ext_tree, si->ext_node);
@@ -378,10 +378,10 @@
 	si->sbi = sbi;
 	sbi->stat_info = si;
 
-	atomic_set(&sbi->total_hit_ext, 0);
-	atomic_set(&sbi->read_hit_rbtree, 0);
-	atomic_set(&sbi->read_hit_largest, 0);
-	atomic_set(&sbi->read_hit_cached, 0);
+	atomic64_set(&sbi->total_hit_ext, 0);
+	atomic64_set(&sbi->read_hit_rbtree, 0);
+	atomic64_set(&sbi->read_hit_largest, 0);
+	atomic64_set(&sbi->read_hit_cached, 0);
 
 	atomic_set(&sbi->inline_xattr, 0);
 	atomic_set(&sbi->inline_inode, 0);