Re: [PATCH 2/4] btrfs: inode: remove variable shadowing in btrfs_invalidatepage()

[Qu Wenruo]

On 2020/12/17 下午1:38, Su Yue wrote:

On Thu 17 Dec 2020 at 12:57, Qu Wenruo <w...@suse.com> wrote:

In btrfs_invalidatepage() we re-declare @tree variable as
btrfs_ordered_inode_tree.

Remove such variable shadowing which can be very confusing.

Signed-off-by: Qu Wenruo <w...@suse.com>
---
 fs/btrfs/inode.c | 9 +++------
 1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index dced71bccaac..b4d36d138008 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c

@@ -8169,6 +8169,7 @@ static void btrfs_invalidatepage(struct page *page, unsigned int offset,

                  unsigned int length)
 {
     struct btrfs_inode *inode = BTRFS_I(page->mapping->host);

+    struct btrfs_ordered_inode_tree *ordered_tree = &inode->ordered_tree;

Any reason for the declaration here? I didn't find that patch[3/4] use it.

Didn't that ordered_tree get used lines below?

     struct extent_io_tree *tree = &inode->io_tree;
     struct btrfs_ordered_extent *ordered;
     struct extent_state *cached_state = NULL;

@@ -8218,15 +8219,11 @@ static void btrfs_invalidatepage(struct page *page, unsigned int offset,

          * for the finish_ordered_io
          */
         if (TestClearPagePrivate2(page)) {
-            struct btrfs_ordered_inode_tree *tree;
-

Better to just rename the @tree to @ordered_tree.

Isn't that exactly what I did?

Thanks,
Qu

-            tree = &inode->ordered_tree;
-
-            spin_lock_irq(&tree->lock);
+            spin_lock_irq(&ordered_tree->lock);
             set_bit(BTRFS_ORDERED_TRUNCATED, &ordered->flags);
             ordered->truncated_len = min(ordered->truncated_len,
                     start - ordered->file_offset);
-            spin_unlock_irq(&tree->lock);
+            spin_unlock_irq(&ordered_tree->lock);

             ASSERT(end - start + 1 < U32_MAX);
             if (btrfs_dec_test_ordered_pending(inode, &ordered,