Re: [PATCH v4 05/36] fs: Convert alloc_inode_sb() to a macro

[Kent Overstreet]

On Mon, Feb 26, 2024 at 04:44:51PM +0100, Vlastimil Babka wrote:
> On 2/21/24 20:40, Suren Baghdasaryan wrote:
> > From: Kent Overstreet <kent.overstreet@xxxxxxxxx>
> > 
> > We're introducing alloc tagging, which tracks memory allocations by
> > callsite. Converting alloc_inode_sb() to a macro means allocations will
> > be tracked by its caller, which is a bit more useful.
> > 
> > Signed-off-by: Kent Overstreet <kent.overstreet@xxxxxxxxx>
> > Signed-off-by: Suren Baghdasaryan <surenb@xxxxxxxxxx>
> > Cc: Alexander Viro <viro@xxxxxxxxxxxxxxxxxx>
> > Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx>
> > ---
> >  include/linux/fs.h | 6 +-----
> >  1 file changed, 1 insertion(+), 5 deletions(-)
> > 
> > diff --git a/include/linux/fs.h b/include/linux/fs.h
> > index 023f37c60709..08d8246399c3 100644
> > --- a/include/linux/fs.h
> > +++ b/include/linux/fs.h
> > @@ -3010,11 +3010,7 @@ int setattr_should_drop_sgid(struct mnt_idmap *idmap,
> >   * This must be used for allocating filesystems specific inodes to set
> >   * up the inode reclaim context correctly.
> >   */
> > -static inline void *
> > -alloc_inode_sb(struct super_block *sb, struct kmem_cache *cache, gfp_t gfp)
> 
> A __always_inline wouldn't have the same effect? Just wondering.

nope, macro expansion within an inline happens once, and will show
__func__ and __line__ of the helper, we want it expanded in the caller