From: Eric Dumazet <edumazet@google.com>
Date: Thu, 22 Jan 2026 04:57:18 +0000 (+0000)
Subject: net: inline net_is_devmem_iov()
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=87918dd4eafc0749a99cb763addc1c37fe7ebb6f;p=thirdparty%2Fkernel%2Flinux.git

net: inline net_is_devmem_iov()

1) Inline this small helper to reduce code size and decrease cpu costs.
2) Constify its argument.
3) Move it to include/net/netmem.h, as a prereq for the following patch.

$ scripts/bloat-o-meter -t vmlinux.2 vmlinux.3
add/remove: 0/2 grow/shrink: 0/4 up/down: 0/-158 (-158)
Function                                     old     new   delta
validate_xmit_skb                            866     857      -9
__pfx_net_is_devmem_iov                       16       -     -16
net_is_devmem_iov                             22       -     -22
get_netmem                                   152     130     -22
put_netmem                                   140     114     -26
tcp_recvmsg_locked                          3860    3797     -63
Total: Before=22566015, After=22565857, chg -0.00%

Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260122045720.1221017-4-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---

diff --git a/include/net/netmem.h b/include/net/netmem.h
index 9e10f4ac50c3..2113a197abb3 100644
--- a/include/net/netmem.h
+++ b/include/net/netmem.h
@@ -389,6 +389,18 @@ static inline unsigned long netmem_get_dma_addr(netmem_ref netmem)
 	return netmem_to_nmdesc(netmem)->dma_addr;
 }
 
+#if defined(CONFIG_NET_DEVMEM)
+static inline bool net_is_devmem_iov(const struct net_iov *niov)
+{
+	return niov->type == NET_IOV_DMABUF;
+}
+#else
+static inline bool net_is_devmem_iov(const struct net_iov *niov)
+{
+	return false;
+}
+#endif
+
 void get_netmem(netmem_ref netmem);
 void put_netmem(netmem_ref netmem);
 
diff --git a/net/core/devmem.c b/net/core/devmem.c
index 185ed2a73d1c..63f093f7d2b2 100644
--- a/net/core/devmem.c
+++ b/net/core/devmem.c
@@ -30,11 +30,6 @@ static DEFINE_XARRAY_FLAGS(net_devmem_dmabuf_bindings, XA_FLAGS_ALLOC1);
 
 static const struct memory_provider_ops dmabuf_devmem_ops;
 
-bool net_is_devmem_iov(struct net_iov *niov)
-{
-	return niov->type == NET_IOV_DMABUF;
-}
-
 static void net_devmem_dmabuf_free_chunk_owner(struct gen_pool *genpool,
 					       struct gen_pool_chunk *chunk,
 					       void *not_used)
diff --git a/net/core/devmem.h b/net/core/devmem.h
index 2534c8144212..1c5c18581fcb 100644
--- a/net/core/devmem.h
+++ b/net/core/devmem.h
@@ -141,7 +141,7 @@ struct net_iov *
 net_devmem_alloc_dmabuf(struct net_devmem_dmabuf_binding *binding);
 void net_devmem_free_dmabuf(struct net_iov *ppiov);
 
-bool net_is_devmem_iov(struct net_iov *niov);
+
 struct net_devmem_dmabuf_binding *
 net_devmem_get_binding(struct sock *sk, unsigned int dmabuf_id);
 struct net_iov *
@@ -214,11 +214,6 @@ static inline u32 net_devmem_iov_binding_id(const struct net_iov *niov)
 	return 0;
 }
 
-static inline bool net_is_devmem_iov(struct net_iov *niov)
-{
-	return false;
-}
-
 static inline struct net_devmem_dmabuf_binding *
 net_devmem_get_binding(struct sock *sk, unsigned int dmabuf_id)
 {