On Fri, Jun 16, 2023 at 05:12:44PM +0100, David Howells wrote:
...
> +/**
> + * alloc_skb_frag - Allocate a page fragment for using in a socket
> + * @fragsz: The size of fragment required
> + * @gfp: Allocation flags
> + */
> +void *alloc_skb_frag(size_t fragsz, gfp_t gfp)
> +{
> + struct skb_splice_frag_cache *cache;
> + struct folio *folio, *spare = NULL;
> + size_t offset, fsize;
> + void *p;
> +
> + if (WARN_ON_ONCE(fragsz == 0))
> + fragsz = 1;
> +
> + cache = get_cpu_ptr(&skb_splice_frag_cache);
> +reload:
> + folio = cache->folio;
> + offset = cache->offset;
> +try_again:
> + if (fragsz > offset)
> + goto insufficient_space;
> +
> + /* Make the allocation. */
> + cache->pagecnt_bias--;
> + offset = ALIGN_DOWN(offset - fragsz, SMP_CACHE_BYTES);
> + cache->offset = offset;
> + p = cache->virt + offset;
> + put_cpu_ptr(skb_splice_frag_cache);
Hi David,
I don't think it makes any difference at run-time.
But to keep Sparse happy, perhaps this ought to be put_cpu_var()
...
