On Monday 07 August 2006 08:01, Evgeniy Polyakov wrote:
> Hello.
>
> Attached patch allows to avoid unnecessary alignment overhead
> in skb->data allocation.
> Main idea is to allocate struct skb_shared_info from cache when
> addition of sizeof(struct skb_shared_info) ens up in different order
> allocation than initial size order.
> This allows to solve problem with 4k allocations for 1500 MTU and 32k
> allocations for 9k jumbo frames for some chips.
> Patch was not tested, so if idea worth it I will complete it.
>
> Signed-off-by: Evgeniy Polyakov <[EMAIL PROTECTED]>
>
> + if ((1UL << order) > size + sizeof(void *) + sizeof(struct
> skb_shared_info)) { + data = ____kmalloc(size + sizeof(struct
> skb_shared_info), gfp_mask); + if (!data)
> + goto nodata;
> + memset(skb, 0, offsetof(struct sk_buff, truesize));
> + } else {
> + unsigned long *ptr;
> +
> + data = ____kmalloc(size, gfp_mask);
You certainly want to kmalloc(size + sizeof(void *)) here, dont you ?
> + if (!data)
> + goto nodata;
> + sh = kmem_cache_alloc(skbuff_shared_info_cache, gfp_mask);
> + if (!sh) {
> + kfree(data);
> + goto nodata;
> + }
> + memset(skb, 0, offsetof(struct sk_buff, truesize));
> + skb->shinfo_cache = 1;
> + ptr = data;
> + ptr[size] = sh;
Eric
-
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at http://vger.kernel.org/majordomo-info.html
