From: Eric Dumazet <edumazet@google.com>
Date: Sun, 16 Nov 2025 20:27:16 +0000 (+0000)
Subject: net: __alloc_skb() cleanup
X-Git-Tag: v6.19-rc1~170^2~131^2~1
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=294e63825966319e815e469931cfbfc437004d0f;p=thirdparty%2Fkernel%2Flinux.git

net: __alloc_skb() cleanup

This patch refactors __alloc_skb() to prepare the following one,
and does not change functionality.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Jason Xing <kerneljasonxing@gmail.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20251116202717.1542829-3-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---

diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 88b5530f9c460..8a0a4ca7fa5db 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -646,25 +646,33 @@ out:
 struct sk_buff *__alloc_skb(unsigned int size, gfp_t gfp_mask,
 			    int flags, int node)
 {
+	struct sk_buff *skb = NULL;
 	struct kmem_cache *cache;
-	struct sk_buff *skb;
 	bool pfmemalloc;
 	u8 *data;
 
-	cache = (flags & SKB_ALLOC_FCLONE)
-		? net_hotdata.skbuff_fclone_cache : net_hotdata.skbuff_cache;
-
 	if (sk_memalloc_socks() && (flags & SKB_ALLOC_RX))
 		gfp_mask |= __GFP_MEMALLOC;
 
-	/* Get the HEAD */
-	if ((flags & (SKB_ALLOC_FCLONE | SKB_ALLOC_NAPI)) == SKB_ALLOC_NAPI &&
-	    likely(node == NUMA_NO_NODE || node == numa_mem_id()))
+	if (flags & SKB_ALLOC_FCLONE) {
+		cache = net_hotdata.skbuff_fclone_cache;
+		goto fallback;
+	}
+	cache = net_hotdata.skbuff_cache;
+	if (unlikely(node != NUMA_NO_NODE && node != numa_mem_id()))
+		goto fallback;
+
+	if (flags & SKB_ALLOC_NAPI) {
 		skb = napi_skb_cache_get(true);
-	else
+		if (unlikely(!skb))
+			return NULL;
+	}
+	if (!skb) {
+fallback:
 		skb = kmem_cache_alloc_node(cache, gfp_mask & ~GFP_DMA, node);
-	if (unlikely(!skb))
-		return NULL;
+		if (unlikely(!skb))
+			return NULL;
+	}
 	prefetchw(skb);
 
 	/* We do our best to align skb_shared_info on a separate cache