Re: [PATCH] btrfs: replace kcalloc() calls to kzalloc_objs()
From: Qu Wenruo
Date: Tue Feb 24 2026 - 01:55:07 EST
在 2026/2/24 17:16, Miquel Sabaté Solà 写道:
Johannes Thumshirn @ 2026-02-24 06:32 GMT:
On 2/24/26 12:45 AM, Miquel Sabaté Solà wrote:
Commit 2932ba8d9c99 ("slab: Introduce kmalloc_obj() and family")Namely?
introduced, among many others, the kzalloc_objs() helper, which has some
benefits over kcalloc().
I didn't want to repeat the arguments from the quoted commit
2932ba8d9c99 ("slab: Introduce kmalloc_obj() and family"). Namely:
If you assume every btrfs developer is aware of all slab/mm/vfs/whatever subsystem development, then I'd say you're wrong.
Thus you should mention the commit (which is not yet in our developmenet tree), and at least have a short reason on the benefit.
Internal introspection of the allocated type now becomes possible,
allowing for future alignment-aware choices to be made by the
allocator and future hardening work that can be type sensitive.
Should I put this in the commit message as well, regardless of the
commit explaining this being quoted?
There's also the argument of dropping 'sizeof' to be more ergonomic. To
me, though, and considering how these helpers have been applied
tree-wide, I see this change more as aligning us with this recent
tree-wide move, which also affected btrfs (see commit 69050f8d6d07
"treewide: Replace kmalloc with kmalloc_obj for non-scalar types").