net: allow > 0 order atomic page alloc in skb_page_frag_refill

skb_page_frag_refill currently permits only order-0 page allocs
unless GFP_WAIT is used. Change skb_page_frag_refill to attempt
higher-order page allocations whether or not GFP_WAIT is used. If
memory cannot be allocated, the allocator will fall back to
successively smaller page allocs (down to order-0 page allocs).

This change brings skb_page_frag_refill in line with the existing
page allocation strategy employed by netdev_alloc_frag, which attempts
higher-order page allocations whether or not GFP_WAIT is set, falling
back to successively lower-order page allocations on failure. Part
of migration of virtio-net to per-receive queue page frag allocators.

Acked-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Michael Dalton <mwdalton@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/core/sock.c b/net/core/sock.c
index 85ad6f0..b3f7ee3 100644 (file)
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -1836,9 +1836,7 @@ bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t prio)
                put_page(pfrag->page);
        }
 
-       /* We restrict high order allocations to users that can afford to wait */
-       order = (prio & __GFP_WAIT) ? SKB_FRAG_PAGE_ORDER : 0;
-
+       order = SKB_FRAG_PAGE_ORDER;
        do {
                gfp_t gfp = prio;