On 7/11/23 09:09, David Hildenbrand wrote:
...
Can we make that a __weak function instead?
We can. It is confusing because we do have these two patterns within the kernel where we use
#ifndef x
#endif
vs
__weak x
What is the recommended way to override ? I have mostly been using #ifndef for most of the arch overrides till now.
I think when placing the implementation in a C file, it's __weak. But don't ask me :)
We do this already for arch_get_mappable_range() in mm/memory_hotplug.c and IMHO it looks quite nice.
It does look nice. I always forget which parts are supposed to be
__weak, so I went to check Documentation/ , and it was quite
entertaining. There are only two search hits: one trivial reference in
Documentation/conf.py, and the other in checkpatch.rst, which says:
**WEAK_DECLARATION**
Using weak declarations like __attribute__((weak)) or __weak
can have unintended link defects. Avoid using them.
...which seems deeply out of touch with how arch layers work these days,
doesn't it? (This is not rhetorical; I'm asking in order to get an
opinion or two on the topic.)
thanks,
--
John Hubbard
NVIDIA
