net: skbuff: sprinkle more __GFP_NOWARN on ingress allocs

build_skb() and frag allocations done with GFP_ATOMIC will
fail in real life, when system is under memory pressure,
and there's nothing we can do about that. So no point
printing warnings.

Signed-off-by: Jakub Kicinski <[email protected]>
Reviewed-by: Eric Dumazet <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

Author: kuba-moo

net/core/skbuff.c

@@ -314,8 +314,8 @@ void *__napi_alloc_frag_align(unsigned int fragsz, unsigned int align_mask)
 	fragsz = SKB_DATA_ALIGN(fragsz);
 
 	local_lock_nested_bh(&napi_alloc_cache.bh_lock);
-	data = __page_frag_alloc_align(&nc->page, fragsz, GFP_ATOMIC,
-				       align_mask);
+	data = __page_frag_alloc_align(&nc->page, fragsz,
+				       GFP_ATOMIC | __GFP_NOWARN, align_mask);
 	local_unlock_nested_bh(&napi_alloc_cache.bh_lock);
 	return data;
 
@@ -330,7 +330,8 @@ void *__netdev_alloc_frag_align(unsigned int fragsz, unsigned int align_mask)
 		struct page_frag_cache *nc = this_cpu_ptr(&netdev_alloc_cache);
 
 		fragsz = SKB_DATA_ALIGN(fragsz);
-		data = __page_frag_alloc_align(nc, fragsz, GFP_ATOMIC,
+		data = __page_frag_alloc_align(nc, fragsz,
+					       GFP_ATOMIC | __GFP_NOWARN,
 					       align_mask);
 	} else {
 		local_bh_disable();
@@ -349,7 +350,7 @@ static struct sk_buff *napi_skb_cache_get(void)
 	local_lock_nested_bh(&napi_alloc_cache.bh_lock);
 	if (unlikely(!nc->skb_count)) {
 		nc->skb_count = kmem_cache_alloc_bulk(net_hotdata.skbuff_cache,
-						      GFP_ATOMIC,
+						      GFP_ATOMIC | __GFP_NOWARN,
 						      NAPI_SKB_CACHE_BULK,
 						      nc->skb_cache);
 		if (unlikely(!nc->skb_count)) {
@@ -418,7 +419,8 @@ struct sk_buff *slab_build_skb(void *data)
 	struct sk_buff *skb;
 	unsigned int size;
 
-	skb = kmem_cache_alloc(net_hotdata.skbuff_cache, GFP_ATOMIC);
+	skb = kmem_cache_alloc(net_hotdata.skbuff_cache,
+			       GFP_ATOMIC | __GFP_NOWARN);
 	if (unlikely(!skb))
 		return NULL;
 
@@ -469,7 +471,8 @@ struct sk_buff *__build_skb(void *data, unsigned int frag_size)
 {
 	struct sk_buff *skb;
 
-	skb = kmem_cache_alloc(net_hotdata.skbuff_cache, GFP_ATOMIC);
+	skb = kmem_cache_alloc(net_hotdata.skbuff_cache,
+			       GFP_ATOMIC | __GFP_NOWARN);
 	if (unlikely(!skb))
 		return NULL;