linux-kernel - [f2fs-dev][PATCH 1/2] f2fs: get rid of kzalloc in __recover_inline

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Date:	Tue, 06 Jan 2015 14:28:43 +0800
From:	Chao Yu <chao2.yu@...sung.com>
To:	Jaegeuk Kim <jaegeuk@...nel.org>,
	Changman Lee <cm224.lee@...sung.com>
Cc:	linux-f2fs-devel@...ts.sourceforge.net,
	linux-kernel@...r.kernel.org
Subject: [f2fs-dev][PATCH 1/2] f2fs: get rid of kzalloc in
 __recover_inline_status

We use kzalloc to allocate memory in __recover_inline_status, and use this
all-zero memory to check the inline date content of inode page by comparing
them. This is low effective and not needed, let's check inline date content
directly.

Signed-off-by: Chao Yu <chao2.yu@...sung.com>
---
 fs/f2fs/inode.c | 27 +++++++++++----------------
 1 file changed, 11 insertions(+), 16 deletions(-)

diff --git a/fs/f2fs/inode.c b/fs/f2fs/inode.c
index 3a8958d..8be0fd5 100644
--- a/fs/f2fs/inode.c
+++ b/fs/f2fs/inode.c
@@ -67,29 +67,25 @@ static void __set_inode_rdev(struct inode *inode, struct f2fs_inode *ri)
 	}
 }
 
-static int __recover_inline_status(struct inode *inode, struct page *ipage)
+static void __recover_inline_status(struct inode *inode, struct page *ipage)
 {
 	void *inline_data = inline_data_addr(ipage);
+	__le32 *start = inline_data;
+	__le32 *end = start + MAX_INLINE_DATA / sizeof(__le32);
 	struct f2fs_inode *ri;
-	void *zbuf;
-
-	zbuf = kzalloc(MAX_INLINE_DATA, GFP_NOFS);
-	if (!zbuf)
-		return -ENOMEM;
-
-	if (!memcmp(zbuf, inline_data, MAX_INLINE_DATA)) {
-		kfree(zbuf);
-		return 0;
-	}
-	kfree(zbuf);
 
+	while (start < end)
+		if (*start++)
+			goto recover;
+	return;
+recover:
 	f2fs_wait_on_page_writeback(ipage, NODE);
 	set_inode_flag(F2FS_I(inode), FI_DATA_EXIST);
 
 	ri = F2FS_INODE(ipage);
 	set_raw_inline(F2FS_I(inode), ri);
 	set_page_dirty(ipage);
-	return 0;
+	return;
 }
 
 static int do_read_inode(struct inode *inode)
@@ -98,7 +94,6 @@ static int do_read_inode(struct inode *inode)
 	struct f2fs_inode_info *fi = F2FS_I(inode);
 	struct page *node_page;
 	struct f2fs_inode *ri;
-	int err = 0;
 
 	/* Check if ino is within scope */
 	if (check_nid_range(sbi, inode->i_ino)) {
@@ -142,7 +137,7 @@ static int do_read_inode(struct inode *inode)
 
 	/* check data exist */
 	if (f2fs_has_inline_data(inode) && !f2fs_exist_data(inode))
-		err = __recover_inline_status(inode, node_page);
+		__recover_inline_status(inode, node_page);
 
 	/* get rdev by using inline_info */
 	__get_inode_rdev(inode, ri);
@@ -152,7 +147,7 @@ static int do_read_inode(struct inode *inode)
 	stat_inc_inline_inode(inode);
 	stat_inc_inline_dir(inode);
 
-	return err;
+	return 0;
 }
 
 struct inode *f2fs_iget(struct super_block *sb, unsigned long ino)
-- 
2.2.1


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