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

From: Vlastimil Babka
Date: Fri Feb 16 2024 - 11:52:51 EST


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@xxxxxxxxxx>
> Co-developed-by: Kent Overstreet <kent.overstreet@xxxxxxxxx>
> Signed-off-by: Kent Overstreet <kent.overstreet@xxxxxxxxx>


> -}
> +#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.