iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

xfs: compile out v4 support if disabled

Browse Source 
Add a few strategic IS_ENABLED statements to let the compiler eliminate
unused code when CONFIG_XFS_SUPPORT_V4 is disabled.

This saves multiple kilobytes of .text in my .config:

$ size xfs.o.*
text	   data	    bss	    dec	    hex	filename
1363633	 294836	    592	1659061	 1950b5	xfs.o.new
1371453	 294868	    592	1666913	 196f61	xfs.o.old

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
This commit is contained in:
Christoph Hellwig 2024-04-22 08:13:16 +02:00 committed by Chandan Babu R
parent c0ac6cb251
commit 4887e53163
2 changed files with 44 additions and 18 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

40
fs/xfs/xfs_mount.h
View File

@ -332,19 +332,10 @@ static inline void xfs_add_ ## name (struct xfs_mount *mp) \
__XFS_ADD_FEAT(attr, ATTR)
__XFS_HAS_FEAT(nlink, NLINK)
__XFS_ADD_FEAT(quota, QUOTA)
__XFS_HAS_FEAT(align, ALIGN)
__XFS_HAS_FEAT(dalign, DALIGN)
__XFS_HAS_FEAT(logv2, LOGV2)
__XFS_HAS_FEAT(sector, SECTOR)
__XFS_HAS_FEAT(extflg, EXTFLG)
__XFS_HAS_FEAT(asciici, ASCIICI)
__XFS_HAS_FEAT(lazysbcount, LAZYSBCOUNT)
__XFS_ADD_FEAT(attr2, ATTR2)
__XFS_HAS_FEAT(parent, PARENT)
__XFS_ADD_FEAT(projid32, PROJID32)
__XFS_HAS_FEAT(crc, CRC)
__XFS_HAS_FEAT(v3inodes, V3INODES)
__XFS_HAS_FEAT(pquotino, PQUOTINO)
__XFS_HAS_FEAT(ftype, FTYPE)
__XFS_HAS_FEAT(finobt, FINOBT)
__XFS_HAS_FEAT(rmapbt, RMAPBT)
@ -358,6 +349,37 @@ __XFS_HAS_FEAT(needsrepair, NEEDSREPAIR)
__XFS_HAS_FEAT(large_extent_counts, NREXT64)
__XFS_HAS_FEAT(exchange_range, EXCHANGE_RANGE)
/*
* Some features are always on for v5 file systems, allow the compiler to
* eliminiate dead code when building without v4 support.
*/
#define __XFS_HAS_V4_FEAT(name, NAME) \
static inline bool xfs_has_ ## name (struct xfs_mount *mp) \
{ \
return !IS_ENABLED(CONFIG_XFS_SUPPORT_V4) || \
(mp->m_features & XFS_FEAT_ ## NAME); \
}
#define __XFS_ADD_V4_FEAT(name, NAME) \
__XFS_HAS_V4_FEAT(name, NAME); \
static inline void xfs_add_ ## name (struct xfs_mount *mp) \
{ \
if (IS_ENABLED(CONFIG_XFS_SUPPORT_V4)) { \
mp->m_features |= XFS_FEAT_ ## NAME; \
xfs_sb_version_add ## name(&mp->m_sb); \
} \
}
__XFS_HAS_V4_FEAT(align, ALIGN)
__XFS_HAS_V4_FEAT(logv2, LOGV2)
__XFS_HAS_V4_FEAT(extflg, EXTFLG)
__XFS_HAS_V4_FEAT(lazysbcount, LAZYSBCOUNT)
__XFS_ADD_V4_FEAT(attr2, ATTR2)
__XFS_ADD_V4_FEAT(projid32, PROJID32)
__XFS_HAS_V4_FEAT(v3inodes, V3INODES)
__XFS_HAS_V4_FEAT(crc, CRC)
__XFS_HAS_V4_FEAT(pquotino, PQUOTINO)
/*
* Mount features
*

22
fs/xfs/xfs_super.c
View File

@ -1580,17 +1580,21 @@ xfs_fs_fill_super(
if (error)
goto out_free_sb;
/* V4 support is undergoing deprecation. */
if (!xfs_has_crc(mp)) {
#ifdef CONFIG_XFS_SUPPORT_V4
/*
* V4 support is undergoing deprecation.
*
* Note: this has to use an open coded m_features check as xfs_has_crc
* always returns false for !CONFIG_XFS_SUPPORT_V4.
*/
if (!(mp->m_features & XFS_FEAT_CRC)) {
if (!IS_ENABLED(CONFIG_XFS_SUPPORT_V4)) {
xfs_warn(mp,
"Deprecated V4 format (crc=0) not supported by kernel.");
error = -EINVAL;
goto out_free_sb;
}
xfs_warn_once(mp,
"Deprecated V4 format (crc=0) will not be supported after September 2030.");
#else
xfs_warn(mp,
"Deprecated V4 format (crc=0) not supported by kernel.");
error = -EINVAL;
goto out_free_sb;
#endif
}
/* ASCII case insensitivity is undergoing deprecation. */