[PATCH v2 1/3] f2fs: avoid opened loop codes in __add_ino_entry

From: Chao Yu
Date: Tue Nov 07 2017 - 00:43:15 EST


We will keep __add_ino_entry success all the time, for ENOMEM failure
case, we have already handled it by using __GFP_NOFAIL flag, so we
don't have to use additional opened loop codes here, remove them.

Signed-off-by: Chao Yu <yuchao0@xxxxxxxxxx>
---
v2:
As Michal Hocko suggested, with __GFP_NOFAIL, MM will do all it can for
memory allocation including access memory reserves, so it's better to
use it rather than opened loop code, update this patch for it.
fs/f2fs/checkpoint.c | 19 +++++++++++--------
1 file changed, 11 insertions(+), 8 deletions(-)

diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c
index 98777c1ae70c..80b90146cff2 100644
--- a/fs/f2fs/checkpoint.c
+++ b/fs/f2fs/checkpoint.c
@@ -405,20 +405,21 @@ static void __add_ino_entry(struct f2fs_sb_info *sbi, nid_t ino,
{
struct inode_management *im = &sbi->im[type];
struct ino_entry *e, *tmp;
+ bool preloaded;
+ int err;

tmp = f2fs_kmem_cache_alloc(ino_entry_slab, GFP_NOFS);
-retry:
- radix_tree_preload(GFP_NOFS | __GFP_NOFAIL);
+
+ preloaded = !radix_tree_preload(GFP_NOFS | __GFP_NOFAIL);
+ f2fs_bug_on(sbi, !preloaded);

spin_lock(&im->ino_lock);
e = radix_tree_lookup(&im->ino_root, ino);
if (!e) {
e = tmp;
- if (radix_tree_insert(&im->ino_root, ino, e)) {
- spin_unlock(&im->ino_lock);
- radix_tree_preload_end();
- goto retry;
- }
+ err = radix_tree_insert(&im->ino_root, ino, e);
+ f2fs_bug_on(sbi, err);
+
memset(e, 0, sizeof(struct ino_entry));
e->ino = ino;

@@ -431,7 +432,9 @@ static void __add_ino_entry(struct f2fs_sb_info *sbi, nid_t ino,
f2fs_set_bit(devidx, (char *)&e->dirty_device);

spin_unlock(&im->ino_lock);
- radix_tree_preload_end();
+
+ if (preloaded)
+ radix_tree_preload_end();

if (e != tmp)
kmem_cache_free(ino_entry_slab, tmp);
--
2.15.0.55.gc2ece9dc4de6