__alloc_skb — allocate a network buffer
| struct sk_buff * __alloc_skb ( | unsigned int size, | 
| gfp_t gfp_mask, | |
| int flags, | |
| int node ); | 
sizesize to allocate
gfp_maskallocation mask
flagsIf SKB_ALLOC_FCLONE is set, allocate from fclone cache instead of head cache and allocate a cloned (child) skb. If SKB_ALLOC_RX is set, __GFP_MEMALLOC will be used for allocations in case the data is required for writeback
nodenuma node to allocate memory on
   Allocate a new sk_buff. The returned buffer has no headroom and a
   tail room of at least size bytes. The object has a reference count
   of one. The return is the buffer. On a failure the return is NULL.
   
   Buffers may only be allocated from interrupts using a gfp_mask of
   GFP_ATOMIC.