ext4: remove unreachable code in ext4_can_extents_be_merged() (da0169b3) · Commits · 戴 / test

Commit ("ext4: disable merging of uninitialized extents") ensured that if either extent under consideration is uninit, we decline to merge, and immediately return. But right after that test, we test again for an uninit extent; we can never hit this. So just remove the impossible test and associated variable. Signed-off-by:

Eric Sandeen <sandeen@redhat.com> Signed-off-by:

"Theodore Ts'o" <tytso@mit.edu> Reviewed-by:

Zheng Liu <wenqing.lz@taobao.com>

fs/ext4/extents.c

+2 −7

Original line number	Diff line number	Diff line
		@@ -1666,7 +1666,7 @@ int
		ext4_can_extents_be_merged(struct inode inode, struct ext4_extent ex1,
		struct ext4_extent *ex2)
		{
		unsigned short ext1_ee_len, ext2_ee_len, max_len;
		unsigned short ext1_ee_len, ext2_ee_len;

		/*
		* Make sure that both extents are initialized. We don't merge
		@@ -1677,11 +1677,6 @@ ext4_can_extents_be_merged(struct inode inode, struct ext4_extent ex1,
		if (ext4_ext_is_uninitialized(ex1) \|\| ext4_ext_is_uninitialized(ex2))
		return 0;

		if (ext4_ext_is_uninitialized(ex1))
		max_len = EXT_UNINIT_MAX_LEN;
		else
		max_len = EXT_INIT_MAX_LEN;

		ext1_ee_len = ext4_ext_get_actual_len(ex1);
		ext2_ee_len = ext4_ext_get_actual_len(ex2);

		@@ -1694,7 +1689,7 @@ ext4_can_extents_be_merged(struct inode inode, struct ext4_extent ex1,
		* as an RO_COMPAT feature, refuse to merge to extents if
		* this can result in the top bit of ee_len being set.
		*/
		if (ext1_ee_len + ext2_ee_len > max_len)
		if (ext1_ee_len + ext2_ee_len > EXT_INIT_MAX_LEN)
		return 0;
		#ifdef AGGRESSIVE_TEST
		if (ext1_ee_len >= 4)

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