[PATCH net-next 7/8] net/tls: reorganize struct tls_context

[Jakub Kicinski]

struct tls_context is slightly badly laid out.  If we reorder things
right we can save 16 bytes (320 -> 304) but also make all fast path
data fit into two cache lines (one read only and one read/write,
down from four cache lines).

Signed-off-by: Jakub Kicinski <jakub.kicin...@netronome.com>
Reviewed-by: Dirk van der Merwe <dirk.vanderme...@netronome.com>
---
 include/net/tls.h | 26 +++++++++++++++-----------
 1 file changed, 15 insertions(+), 11 deletions(-)

diff --git a/include/net/tls.h b/include/net/tls.h
index 39ea62f0c1f6..a463a6074e5d 100644
--- a/include/net/tls.h
+++ b/include/net/tls.h
@@ -236,34 +236,32 @@ struct tls_prot_info {
 };
 
 struct tls_context {
+       /* read-only cache line */
        struct tls_prot_info prot_info;
 
-       union tls_crypto_context crypto_send;
-       union tls_crypto_context crypto_recv;
+       u8 tx_conf:3;
+       u8 rx_conf:3;
 
-       struct list_head list;
-       struct net_device *netdev;
-       refcount_t refcount;
+       int (*push_pending_record)(struct sock *sk, int flags);
+       void (*sk_write_space)(struct sock *sk);
 
        void *priv_ctx_tx;
        void *priv_ctx_rx;
 
-       u8 tx_conf:3;
-       u8 rx_conf:3;
+       struct net_device *netdev;
 
+       /* rw cache line */
        struct cipher_context tx;
        struct cipher_context rx;
 
        struct scatterlist *partially_sent_record;
        u16 partially_sent_offset;
 
-       unsigned long flags;
        bool in_tcp_sendpages;
        bool pending_open_record_frags;
+       unsigned long flags;
 
-       int (*push_pending_record)(struct sock *sk, int flags);
-
-       void (*sk_write_space)(struct sock *sk);
+       /* cache cold stuff */
        void (*sk_destruct)(struct sock *sk);
        void (*sk_proto_close)(struct sock *sk, long timeout);
 
@@ -275,6 +273,12 @@ struct tls_context {
                           int __user *optlen);
        int  (*hash)(struct sock *sk);
        void (*unhash)(struct sock *sk);
+
+       union tls_crypto_context crypto_send;
+       union tls_crypto_context crypto_recv;
+
+       struct list_head list;
+       refcount_t refcount;
 };
 
 enum tls_offload_ctx_dir {
-- 
2.21.0