f2fs: remove percpu_count due to performance regression

commit 35782b233f37e48ecc469d9c7232f3f6a7fad41a upstream.

This patch removes percpu_count usage due to performance regression in iozone.

Fixes: 523be8a6b3 ("f2fs: use percpu_counter for page counters")
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index 8021d35..013c6a5 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -688,10 +688,6 @@
 
 static void destroy_percpu_info(struct f2fs_sb_info *sbi)
 {
-	int i;
-
-	for (i = 0; i < NR_COUNT_TYPE; i++)
-		percpu_counter_destroy(&sbi->nr_pages[i]);
 	percpu_counter_destroy(&sbi->alloc_valid_block_count);
 	percpu_counter_destroy(&sbi->total_valid_inode_count);
 }
@@ -1442,6 +1438,7 @@
 static void init_sb_info(struct f2fs_sb_info *sbi)
 {
 	struct f2fs_super_block *raw_super = sbi->raw_super;
+	int i;
 
 	sbi->log_sectors_per_block =
 		le32_to_cpu(raw_super->log_sectors_per_block);
@@ -1466,6 +1463,9 @@
 	sbi->interval_time[REQ_TIME] = DEF_IDLE_INTERVAL;
 	clear_sbi_flag(sbi, SBI_NEED_FSCK);
 
+	for (i = 0; i < NR_COUNT_TYPE; i++)
+		atomic_set(&sbi->nr_pages[i], 0);
+
 	INIT_LIST_HEAD(&sbi->s_list);
 	mutex_init(&sbi->umount_mutex);
 	mutex_init(&sbi->wio_mutex[NODE]);
@@ -1481,13 +1481,7 @@
 
 static int init_percpu_info(struct f2fs_sb_info *sbi)
 {
-	int i, err;
-
-	for (i = 0; i < NR_COUNT_TYPE; i++) {
-		err = percpu_counter_init(&sbi->nr_pages[i], 0, GFP_KERNEL);
-		if (err)
-			return err;
-	}
+	int err;
 
 	err = percpu_counter_init(&sbi->alloc_valid_block_count, 0, GFP_KERNEL);
 	if (err)