Re: [PATCH 1/3] ext4: make fast commit support optional

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential
issue to consider:
- [Medium] ext4: build failure exporting static inline
  ext4_fc_init_inode()
--

commit 2b96da3e6bb4354cc67ea3393ddf5ce91b735978
Author: Max Kellermann <max.kellermann@ionos.com>

ext4: make fast commit support optional

This commit adds CONFIG_EXT4_FS_FAST_COMMIT to allow compiling out fast
commit support and reducing in-memory inode size.

> diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
> index 8d3af062a8306..34843fcc1008b 100644
> --- a/fs/ext4/ext4.h
> +++ b/fs/ext4/ext4.h

[ ... ]

> @@ -3109,6 +3123,55 @@ void ext4_fc_destroy_dentry_cache(void);
>  int ext4_fc_record_regions(struct super_block *sb, int ino,
>  			   ext4_lblk_t lblk, ext4_fsblk_t pblk,
>  			   int len, int replay);
> +#else
> +static inline bool ext4_fc_inode_tracked(struct inode *inode)
> +{
> +	return false;
> +}
> +
> +static inline void ext4_fc_init(struct super_block *sb, journal_t *journal) {}
> +static inline void ext4_fc_init_inode(struct inode *inode) {}

[Severity: Medium]
Does making ext4_fc_init_inode() a static inline stub break the build when
CONFIG_EXT4_FS_FAST_COMMIT is disabled and CONFIG_EXT4_KUNIT_TESTS is
enabled?

fs/ext4/mballoc.c unconditionally exports ext4_fc_init_inode() for KUnit
tests:

fs/ext4/mballoc.c:
    ...
    EXPORT_SYMBOL_FOR_EXT4_TEST(mb_set_bits);
    EXPORT_SYMBOL_FOR_EXT4_TEST(ext4_fc_init_inode);
    EXPORT_SYMBOL_FOR_EXT4_TEST(ext4_mb_mark_context);
    #endif

With CONFIG_EXT4_FS_FAST_COMMIT=n, exporting the static inline function
causes a static/non-static declaration conflict or fails in modpost with a
local symbol export error.

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20261111125242.1078620-1-max.kellermann@ionos.com?part=1