Re: [PATCH v3 22/35] mm/slab: enable slab allocation tagging for kmalloc and friends

Kent Overstreet
2024-02-16T17:04:01Z

On Fri, Feb 16, 2024 at 05:52:34PM +0100, Vlastimil Babka wrote:
> On 2/12/24 22:39, Suren Baghdasaryan wrote:
> > Redefine kmalloc, krealloc, kzalloc, kcalloc, etc. to record allocations
> > and deallocations done by these functions.
> >
> > Signed-off-by: Suren Baghdasaryan <surenb@google.com>
> > Co-developed-by: Kent Overstreet <kent.overstreet@linux.dev>
> > Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
>
>
> > -}
> > +#define kvmalloc(_size, _flags) kvmalloc_node(_size, _flags, NUMA_NO_NODE)
> > +#define kvzalloc(_size, _flags) kvmalloc(_size, _flags|__GFP_ZERO)
> >
> > -static inline __alloc_size(1, 2) void *kvmalloc_array(size_t n, size_t size, gfp_t flags)
>
> This has __alloc_size(1, 2)
>
> > -{
> > - size_t bytes;
> > -
> > - if (unlikely(check_mul_overflow(n, size, &bytes)))
> > - return NULL;
> > +#define kvzalloc_node(_size, _flags, _node) kvmalloc_node(_size, _flags|__GFP_ZERO, _node)
> >
> > - return kvmalloc(bytes, flags);
> > -}
> > +#define kvmalloc_array(_n, _size, _flags) \
> > +({ \
> > + size_t _bytes; \
> > + \
> > + !check_mul_overflow(_n, _size, &_bytes) ? kvmalloc(_bytes, _flags) : NULL; \
> > +})
>
> But with the calculation now done in a macro, that's gone?
>
> > -static inline __alloc_size(1, 2) void *kvcalloc(size_t n, size_t size, gfp_t flags)
>
> Same here...
>
> > -{
> > - return kvmalloc_array(n, size, flags | __GFP_ZERO);
> > -}
> > +#define kvcalloc(_n, _size, _flags) kvmalloc_array(_n, _size, _flags|__GFP_ZERO)
>
> ... transitively?
>
> But that's for Kees to review, I'm just not sure if he missed it or it's fine.

I think this is something we want to keep - we'll fix it