Commit d7b26908 authored by Paolo Abeni's avatar Paolo Abeni Committed by David S. Miller
Browse files

mptcp: shrink mptcp_out_options struct 



After the previous patch we can alias with a union several
fields in mptcp_out_options. Such struct is stack allocated and
memset() for each plain TCP out packet. Every saved byted counts.

Before:
pahole -EC mptcp_out_options
 # ...
/* size: 136, cachelines: 3, members: 17 */

After:
pahole -EC mptcp_out_options
 # ...
/* size: 56, cachelines: 1, members: 9 */

Signed-off-by: default avatarPaolo Abeni <pabeni@redhat.com>
Signed-off-by: default avatarMat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 1bff1e43

include/net/mptcp.h

+17 −9
Original line number Diff line number Diff line
@@ -58,10 +58,6 @@ struct mptcp_addr_info { 
struct mptcp_out_options {

#if IS_ENABLED(CONFIG_MPTCP)

	u16 suboptions;

	u64 sndr_key;

	u64 rcvr_key;

	u64 ahmac;

	struct mptcp_addr_info addr;

	struct mptcp_rm_list rm_list;

	u8 join_id;

	u8 backup;
@@ -69,11 +65,23 @@ struct mptcp_out_options { 
	   reset_transient:1,

	   csum_reqd:1,

	   allow_join_id0:1;

	union {

		struct {

			u64 sndr_key;

			u64 rcvr_key;

		};

		struct {

			struct mptcp_addr_info addr;

			u64 ahmac;

		};

		struct mptcp_ext ext_copy;

		struct {

			u32 nonce;

	u64 thmac;

			u32 token;

			u64 thmac;

			u8 hmac[20];

	struct mptcp_ext ext_copy;

		};

	};

#endif

};