net: introduce struct net_hotdata

Instead of spreading networking critical fields
all over the places, add a custom net_hotdata
structure so that we can precisely control its layout.

In this first patch, move :

- gro_normal_batch used in rx (GRO stack)
- offload_base used in rx and tx (GRO and TSO stacks)

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20240306160031.874438-2-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 9 insertions, 0 deletions

diff --git a/net/core/hotdata.c b/net/core/hotdata.c
new file mode 100644
index 000000000000..abb8ad19d59a
--- /dev/null
+++ b/net/core/hotdata.c
@@ -0,0 +1,9 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+#include <net/hotdata.h>
+#include <linux/cache.h>
+#include <linux/list.h>
+
+struct net_hotdata net_hotdata __cacheline_aligned = {
+	.offload_base = LIST_HEAD_INIT(net_hotdata.offload_base),
+	.gro_normal_batch = 8,
+};