On Tue, Sep 14, 2021 at 06:53:35PM +0800, Su Yue wrote:

It looks strange that btrfs_node_key is in struct-funcs.c.
So move it to ctree.h and make it static inline.

"looks strange" is not a sufficient reason. Inlining a function means
that the body will be expanded at each call site, bloating the binary
code. Have you measured the impact of that?

There's some performance cost of an non-inline function due to the call
overhead but it does not make sense to inline a function that's called
rarely and not in a tight loop. If you grep for the function you'd see
that it's called eg. once per function or in a loop that's not
performance critical on first sight (eg. in reada_for_search).