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Date: Mon, 01 Apr 2013 15:55:54 +0900
From: Jaegeuk Kim <jaegeuk.kim@...sung.com>
To: unlisted-recipients:; (no To-header on input)
Cc: Jaegeuk Kim <jaegeuk.kim@...sung.com>,
linux-fsdevel@...r.kernel.org, linux-kernel@...r.kernel.org,
linux-f2fs-devel@...ts.sourceforge.net
Subject: [PATCH 3/9] f2fs: remove redundant lock_page calls
In get_node_page, we do not need to call lock_page all the time.
If the node page is cached as uptodate,
1. grab_cache_page locks the page,
2. read_node_page unlocks the page, and
3. lock_page is called for further process.
Let's avoid this.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@...sung.com>
---
fs/f2fs/node.c | 63 +++++++++++++++++++++++++++++++++-------------------------
1 file changed, 36 insertions(+), 27 deletions(-)
diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
index 10cbee9..c5360b7 100644
--- a/fs/f2fs/node.c
+++ b/fs/f2fs/node.c
@@ -847,32 +847,13 @@ fail:
return ERR_PTR(err);
}
-static int read_node_page(struct page *page, int type)
-{
- struct f2fs_sb_info *sbi = F2FS_SB(page->mapping->host->i_sb);
- struct node_info ni;
-
- get_node_info(sbi, page->index, &ni);
-
- if (ni.blk_addr == NULL_ADDR) {
- f2fs_put_page(page, 1);
- return -ENOENT;
- }
-
- if (PageUptodate(page)) {
- unlock_page(page);
- return 0;
- }
-
- return f2fs_readpage(sbi, page, ni.blk_addr, type);
-}
-
/*
* Readahead a node page
*/
void ra_node_page(struct f2fs_sb_info *sbi, nid_t nid)
{
struct address_space *mapping = sbi->node_inode->i_mapping;
+ struct node_info ni;
struct page *apage;
apage = find_get_page(mapping, nid);
@@ -886,22 +867,40 @@ void ra_node_page(struct f2fs_sb_info *sbi, nid_t nid)
if (!apage)
return;
- if (read_node_page(apage, READA) == 0)
+ get_node_info(sbi, nid, &ni);
+
+ if (ni.blk_addr == NULL_ADDR || PageUptodate(apage)) {
+ f2fs_put_page(apage, 1);
+ return;
+ }
+
+ if (f2fs_readpage(sbi, apage, ni.blk_addr, READA) == 0)
f2fs_put_page(apage, 0);
return;
}
struct page *get_node_page(struct f2fs_sb_info *sbi, pgoff_t nid)
{
- int err;
- struct page *page;
struct address_space *mapping = sbi->node_inode->i_mapping;
+ struct page *page;
+ struct node_info ni;
+ int err;
page = grab_cache_page(mapping, nid);
if (!page)
return ERR_PTR(-ENOMEM);
- err = read_node_page(page, READ_SYNC);
+ get_node_info(sbi, nid, &ni);
+
+ if (ni.blk_addr == NULL_ADDR) {
+ f2fs_put_page(page, 1);
+ return ERR_PTR(-ENOENT);
+ }
+
+ if (PageUptodate(page))
+ goto got_it;
+
+ err = f2fs_readpage(sbi, page, ni.blk_addr, READ_SYNC);
if (err)
return ERR_PTR(err);
@@ -910,6 +909,7 @@ struct page *get_node_page(struct f2fs_sb_info *sbi, pgoff_t nid)
f2fs_put_page(page, 1);
return ERR_PTR(-EIO);
}
+got_it:
BUG_ON(nid != nid_of_node(page));
mark_page_accessed(page);
return page;
@@ -923,6 +923,7 @@ struct page *get_node_page_ra(struct page *parent, int start)
{
struct f2fs_sb_info *sbi = F2FS_SB(parent->mapping->host->i_sb);
struct address_space *mapping = sbi->node_inode->i_mapping;
+ struct node_info ni;
int i, end;
int err = 0;
nid_t nid;
@@ -936,10 +937,18 @@ struct page *get_node_page_ra(struct page *parent, int start)
page = grab_cache_page(mapping, nid);
if (!page)
return ERR_PTR(-ENOMEM);
- else if (PageUptodate(page))
+
+ get_node_info(sbi, nid, &ni);
+
+ if (ni.blk_addr == NULL_ADDR) {
+ f2fs_put_page(page, 1);
+ return ERR_PTR(-ENOENT);
+ }
+
+ if (PageUptodate(page))
goto page_hit;
- err = read_node_page(page, READ_SYNC);
+ err = f2fs_readpage(sbi, page, ni.blk_addr, READ_SYNC);
if (err)
return ERR_PTR(err);
@@ -956,7 +965,7 @@ struct page *get_node_page_ra(struct page *parent, int start)
lock_page(page);
page_hit:
- if (PageError(page)) {
+ if (!PageUptodate(page)) {
f2fs_put_page(page, 1);
return ERR_PTR(-EIO);
}
--
1.8.1.3.566.gaa39828
--
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